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Trophy hunting in Africa: Long-term trends in antelope horn size

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Abstract

Trophy hunting in ungulates may favour individuals with smaller horns. A decrease in horn/antler size may jeopardize the conservation potential of hunting areas, which would be a major concern in Africa where hunting zones represent over half of the total area of protected lands. We investigated horn length trends of harvested male impalas Aepyceros melampus, greater kudus Tragelaphus strepsiceros and sable antelopes Hippotragus niger, from 1974 to 2008 in Matetsi Safari Area, Zimbabwe. Horn length declined by 4% in impalas, partly because male harvest age decreased. In greater kudus, surprisingly, horn length increased by 14%, while mean age of harvested male greater kudus increased during the study period. Reduced hunting pressure on this species during the study may have allowed males to live longer and to grow longer horns before being harvested. Horn length declined by 6% in sable antelopes, independent of age, suggesting that trophy hunting selected male sable antelopes with smaller horns through time, provided that horn length is heritable. Hunting pressure and trophy value were higher for sable antelopes than for impalas and greater kudus. Accordingly, the decline of horn length in this species was more pronounced. More valuable trophy species, such as sable antelopes, require special attention because they may be exposed to higher hunting pressure, and are therefore more likely to experience a decrease in horn size.

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... There are also evolutionary-scale consequences of the selective harvesting of trophy animals with particular heritable phenotypic traits [10,11]. This artificial selection typically leads to a rapid decline (within a few generations) in the desired trophy attributes within the hunted population. ...
... Such traits, including features such as body size, may be linked to other fitness-related attributes, such as physiological tolerances or disease resistance [10] and, thus, would lead to a decline in fitness. These selective pressures, which amount to domestication, vary as a function of hunting intensity, duration, and population size, and, thus, fluctuate among species [11]. Another form of domestication emerging from trophy hunting is the selective breeding for desirable traits in individuals, such as large manes in lions [12] or, in extreme cases, artificially selected color variants maintained by inbreeding [6]. ...
... However, there is considerable debate globally regarding what constitutes a species' 'previous' range, and whether this should be the dominant consideration when deciding whether to assist migration in light of shifting climates [10]. Furthermore, the South African Hunters and Game Conservation Association have strongly denounced selective and intensive game breeding practices (e.g., enhancing or altering genetic characteristics of game species for commercial purposes, including artificial and unnatural manipulation to achieve unusual coat colors and excessive horn lengths), and they have called upon the South African government to implement conservation strategies in the interest of protecting the country's biodiversity [11]. ...
... Some studies have shown that selective harvesting related to trophy hunting may result in the loss of the more desirable phenotypic traits (i.e., horn or tusk size) with increasing hunting pressure [53]. Despite these observations, there are few studies reporting on the decline of trophy size in hunting destinations in southern Africa, e.g., Zambia [54], northwest Zimbabwe [55], and South Africa [56,57]. However, the declines in horn size cannot be attributed solely to selective hunting pressure let alone inbreeding depression but a combination of these with some environmental factors [58]. ...
... Although several studies have been done on trophy hunting of lions and leopards (Panthera pandus) [46,[61][62][63][64], few studies have explored on trophy size related issues on large wild herbivores in southern Africa [44, [55][56][57]. In this study, we explored the temporal dynamics in trophy quality and harvesting patterns of four selected wild herbivores, Cape buffalo (Syncerus caffer), African elephant (Loxodonta africana) and mid-sized herbivores, greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in a semi arid tropical ecosystem, Matetsi Safari Area, a hunting complex within the Kavango Zambezi Transfrontier Conservation Area (KAZA TFCA), northwest of Zimbabwe. ...
... Our results showed that African elephants' age at harvest did not change over time though their trophy size declined. However, in this study for the period 2004-2015 we found sable age at harvest to have increased significantly contrary to the observations for the period 1979-2005 in the same area [55]. On the contrary, the trophy sizes for Cape buffalo and greater kudu have not changed for the period 2004-2015 in Matetsi Safari Area as reported in some countries, e.g., Tanzania [44] and South Africa [56,57]. ...
Article
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The selective nature of trophy hunting may cause changes in desirable phenotypic traits in harvested species. A decline in trophy size of preferred species may reduce hunting destination competitiveness thus compromising the sustainability of trophy hunting as a conservation tool. We explored the trophy quality and trends in harvesting patterns (i.e., 2004–2015) of Cape buffalo (Syncerus caffer), African elephant (Loxodonta africana), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. To analyse the effect of year, area and age on the trophy size, quota size and offtake levels, we used linear mixed models. One sample t-test was used to compare observed trophy size with Safari Club International (SCI) minimum score. Trophy sizes for Cape buffalo and African elephant were below the SCI minimum score. Greater kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015. Age at harvest for Cape buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of African elephant and Greater kudu declined whilst the quota size did not change between 2004 and 2015. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004–2015. The trophy size and harvesting patterns in these species pose a conservation and management dilemma on the sustainability of trophy hunting in this area. We recommend: (1) temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, and (2) introduction of variable trophy fee pricing system based on trophy size.
... Thus, the hunting pressure has been constantly increasing as the market for trophy hunting grows. Trophy hunting is practiced legally in 23 sub-Sahara African countries, and was recorded to generate at least US$ 201 million per year from more or less 18,500 international hunting clients (Lindsey et al. 2006;Groom and Harris 2009;Crosmary et al. 2013), that is before the not yet quantified effects of the novel coronavirus (Covid-19) pandemic. ...
... Thus, trophy hunting can be used to control animal populations. This is consistent with most wildlife ecologists' views that trophy quality and catch per unit effort (CPUE) are major indicators for sustainability in trophy hunting and conservation (Wilfred 2010;Crosmary et al. 2013). When hunting pressure is high the animals tend to be more vigilant thus the hunting effort increases (Wilfred 2010). ...
... When hunting pressure is high the animals tend to be more vigilant thus the hunting effort increases (Wilfred 2010). A decline in trophy quality is assumed to indicate over harvesting and or other factors related to environmental degradation, for example, nutritional deficiency when forage is limited resulting in restrained animal growth (Crosmary et al. 2013). Also, other factors include contest intra-and inter-specific competition which results in reduced body sizes due to shrinking home ranges and less forage as influenced by climate variability (Ramanzin and Sturaro 2014). ...
... Thus, the hunting pressure has been constantly increasing as the market for trophy hunting grows. Trophy hunting is practiced legally in 23 sub-Sahara African countries, and was recorded to generate at least US$ 201 million per year from more or less 18,500 international hunting clients (Lindsey et al. 2006;Groom and Harris 2009;Crosmary et al. 2013), that is before the not yet quantified effects of the novel coronavirus (Covid-19) pandemic. ...
... Thus, trophy hunting can be used to control animal populations. This is consistent with most wildlife ecologists' views that trophy quality and catch per unit effort (CPUE) are major indicators for sustainability in trophy hunting and conservation (Wilfred 2010;Crosmary et al. 2013). When hunting pressure is high the animals tend to be more vigilant thus the hunting effort increases (Wilfred 2010). ...
... When hunting pressure is high the animals tend to be more vigilant thus the hunting effort increases (Wilfred 2010). A decline in trophy quality is assumed to indicate over harvesting and or other factors related to environmental degradation, for example, nutritional deficiency when forage is limited resulting in restrained animal growth (Crosmary et al. 2013). Also, other factors include contest intra-and inter-specific competition which results in reduced body sizes due to shrinking home ranges and less forage as influenced by climate variability (Ramanzin and Sturaro 2014). ...
Article
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This study was based on a temporal analysis of trophy quality trends and hunting effort in Chewore South Safari Area (CSSA), Zimbabwe, for the period 2009-2012. We selected four of the big five species, namely; buffalo (Syncerus caffer), elephant (Loxodonta africana), the leopard (Panthera pardus) and lion (Panthera leo) for analysis. Existing database of 188 trophies from 2009 to 2011 was reviewed and recorded using the Safari Club International (SCI) scoring system. Further, 50 trophies for 2012 were measured and recorded based on the SCI scoring system. Local ecological knowledge on trophy quality and hunting effort in CSSA was obtained through semi-structured questionnaires from 22 conveniently selected professional hunters in 2012. The results indicated no significant change in trophy quality trends of buffalo, leopard and lion (p > 0.05) over the study period. In contrast, there was a significant decline in elephant trophy quality trend over the same period (p < 0.05). The results showed no significant change in hunting effort over the study period for all the four study species (p > 0.05). Furthermore, seventy-two percent (72%, n = 13) of the professional hunters confirmed that elephant population was declining in CSSA and this was likely due to poaching. Professional hunters perceived trophy hunting as a source of financial capital generation for wildlife conservation (61%, n = 11), as well as positively contributing to the local economy (56%, n = 10). It was concluded that hunting has limited negative impact on species trophy quality trends when a sustainable hunting system is consistently followed in CSSA. CSSA management need to continuously monitor trophy hunting, animal populations and employ adaptive management approach to quota setting and species conservation.
... However, if motivation for hunting is mainly exceptional trophy quality, a resultant decline in this desirable attribute may reduce hunter satisfaction [27, 28] and loss of income, to the detriment of conservation and the livelihoods of many local communities depending on wildlife resources. Although the significance of trophy hunting in Africa is well documented, very little attention has been given to trends in trophy quality in African wildlife species other than lions (Panthera leo) [25,29303132. In Zimbabwe, a decline in the trophy quality of three hunted gregarious herbivores, impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi hunting area has been noticed [30]. ...
... Although the significance of trophy hunting in Africa is well documented, very little attention has been given to trends in trophy quality in African wildlife species other than lions (Panthera leo) [25,29303132. In Zimbabwe, a decline in the trophy quality of three hunted gregarious herbivores, impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi hunting area has been noticed [30]. However, considering the significance and contribution of private conservation areas or game farms for wildlife conservation in southern Africa and Zimbabwe in particular [33], the long-term trends in trophy quality and the resultant population dynamics of hunted species in such closed and insularized ecosystems have received little attention in literature. ...
... We collected data on annual off-takes for the three species for the period 1997-2014. Data on offtakes were used to calculate hunting pressure, which we considered to be the number of hunted or cropped individuals (off-take) for a particular year divided by the corresponding population estimate for that year [30]. Secondary data on trophy size were obtained from management records at Cawston Ranch. ...
Article
Long term monitoring of population estimates and trophy size trends is requisite to ensure that trophy hunting is sustainable. We explored the influence of trophy hunting on population size and trophy quality of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) antelopes from 1997 to 2014 in Cawston Ranch, Zimbabwe. Population estimates of the three species showed a cyclical declining trend, albeit being statistically insignificant for the three species. Hunting pressure had no significant effect on the population estimates of the three species for the period 1997-2014. Impala population declined (-30 %) between 2003 and 2008 possibly due to increased illegal hunting pressure associated with land invasions during this period. Trophy size of all species declined over time, 2004-2014, (impala (-1.3 %), kudu (-3.9 %), sable (-2.6 %) possibly due diet quality and loss of genetic variability in these populations. However, trophy size for greater kudu and sable were within the minimum score range of the Safari Club International. We recommend research on genetic variability and inbreeding levels of hunted populations in closed ecosystems to inform adaptive management as a way of ensuring sustainability of trophy hunting as a conservation tool in small isolated parks in Africa.
... Size of harvested trophies. Crosmary et al. (2013) Greater kudu (Tragelaphus strepsiceros) Horn length and ageat-harvest Horn length increased (14%) and age-at-harvest increased, possibly because of decreasing harvest pressure. ...
... Size of harvested trophies. Crosmary et al. (2013) Sable antelope (Hippotragus niger) Horn length and ageat-harvest Horn length decreased (À6%), no change in age-at-harvest. ...
... Size of harvested trophies. Crosmary et al. (2013) Trophy ungulates Trophy size Decline in trophy size for most species. ...
Article
Full-text available
Trophy hunting, the selective removal of animals for human recreation, can contribute to conservation when appropriately managed. Yet, little is known about how harvest rates or different definitions of trophy affect age structure and trophy size in harvested animals and in survivors because no controlled studies exist. To investigate the impacts of different management regimes, we developed an individual-based model for bighorn sheep (Ovis canadensis), based on empirical data on survival from a protected population and data on horn growth from 2 populations that differed in their growth rates. One population showed slow horn growth and the other population fast horn growth. We subjected these model populations to varying harvest rates and 2 different hunting regulations: 4/5 curl and full-curl definitions of a trophy male. We found that the effect of hunting regulations depends on horn growth rate. In populations with fast horn growth, the effects of trophy hunting on male age structure and horn size were greater and the effect of a change in the definition of legal male smaller than in populations with slow growth rates. High harvest rates led to a younger age structure and smaller horn size. Both effects were weakened by a more restrictive definition of trophy male. As harvest rates increased past 40% of legal males, the number of males harvested increased only marginally because an increasing proportion of the harvested males included those that had just become legal. Although our simulation focused on bighorn sheep, the link between horn growth rate and harvest effects may be applicable for any size-selective harvest regime.
... Selective harvest may thus have undesirable evolutionary consequences, such as shorter horns in wild sheep (Douhard, Festa-Bianchet, Pelletier, Gaillard, & Bonenfant, 2016;Garel et al., 2007;Hengeveld & Festa-Bianchet, 2011;Pigeon et al., 2016). Decreasing horn growth over time was also documented by Crosmary et al. (2013) for trophy-hunted male impala Aepyceros melampus and sable antelope Hippotragus niger in Zimbabwe. For greater kudu Tragelaphus strepsiceros, however, horn growth increased over time (Crosmary et al., 2013). ...
... Decreasing horn growth over time was also documented by Crosmary et al. (2013) for trophy-hunted male impala Aepyceros melampus and sable antelope Hippotragus niger in Zimbabwe. For greater kudu Tragelaphus strepsiceros, however, horn growth increased over time (Crosmary et al., 2013). ...
... The potential for harvest refuges to mitigate the selective effects of trophy hunting on secondary sexual traits in terrestrial mammals has rarely been tested. Crosmary et al. (2013) showed that horn size decreased with distance from a harvest refuge in Zimbabwe for only 1 of 3 ungulate species. Pelletier, Festa-Bianchet, Jorgenson, Feder, and Hubbs (2014) found that the horns of bighorn sheep Ovis canadensis males harvested near refuges were 3% longer than those of males harvested far from refuges in Alberta, Canada. ...
Article
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1. Sustainable exploitation must minimize its impact on the ecology and evolution of exploited wildlife. Intense phenotype-based selective harvests can induce evolutionary change. Refuges could mitigate those evolutionary effects if individuals not subject to selective hunting in harvest refuges migrated and reproduced in hunted areas. The role of harvest refuges on phenotypic rescue of trophy-hunted species, however, has rarely been tested. 2. We investigated spatial and temporal variation in the effect of refuges on horn size and age at harvest in bighorn sheep (Ovis canadensis). We analyzed data on 5 826 males harvested over 39 years in Alberta, Canada. 3. Horn length, a trait targeted by hunters, and age at harvest increased with the amount of protected areas 5-40 km around each kill. Horn base circumference, however, was independent of proximity to refuges. 4. The number of males harvested increased during the last 10 days of the hunting season in late October, corresponding with the timing of bighorn male breeding migrations. Males shot during those 10 days were on average 17% closer to a refuge than males shot earlier in the season. Apparently, some large males exit refuges late in the hunting season, are shot, and cannot contribute to rescue. Uncertainty remains about the proportion of males exiting refuges after the hunting season and how many survive to reproduce. 5. Synthesis and applications. Harvest refuges are unlikely to rescue hunted populations of bighorn sheep in Alberta, because some males exiting refuges are at risk of harvest before they mate. For phenotypic rescue to be effective, unselected males must reproduce before they are shot. Closing the hunting season 10 days earlier would increase survival of unselected rams exiting refuges. Key-words: Bighorn sheep, harvest refuge, horn size, phenotypic rescue, protected areas, size-selective harvest, source-sink dynamics, trophy hunting.
... The significant difference in trophy quality for elephant and buffalo as revealed by the test can be attributed to strong hunting selection pressure of certain qualities or morphological traits exhibited by the trophy animals. Crosmary et al, (2013) noted that, hunters preferentially harvest older bulls because they generally have exceptional trophy quality than younger ones. Therefore species exposed to higher hunting pressure and higher trophy selectivity such as elephant and buffalo are more likely to experience a decrease in trophy quality. ...
... Therefore species exposed to higher hunting pressure and higher trophy selectivity such as elephant and buffalo are more likely to experience a decrease in trophy quality. A decrease in trophy size may not only be detrimental to the viability of harvested trophy animals but also to the sustainability of trophy hunting as a conservation tool (Crosmary et al, 2013). ...
... The results revealed that SWRA may be populated by immature low value trophy animals in the long term if measures are not put in place to improve the supply site of trophy quality animals especially for elephants and buffaloes. More valuable trophy animals such as elephant, buffalo, lion, leopard and sable require special attention because they may be exposed to higher hunting pressure hence more likely to experience a decrease in trophy quality (Crosmary et al, 2013). The decline in trophy quality may potentially affect income for the hunting industry if hunters choose to travel to areas where trophy quality is attractive (Crosmary et al, 2013) hence this may create little or no impetus to conserve wildlife species thereby open the door for poaching. ...
Conference Paper
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Trophy quality (size) coupled with stakeholders " perceptions on elephant (Loxodonta africana), lion (Panthera leo) and buffalo (Syncerus caffer) in Sengwa Wildlife Research Area (SWRA), Zimbabwe were analysed so as to determine the trends for the period 2003 to 2013. Trophy quality data were obtained from hunting records kept at station level in SWRA and Hunting Return Forms (TR2) database kept at Zimbabwe Parks and Wildlife Management Authority headquarters. Thirty key stakeholders " perceptions were determined using a questionnaire survey consisting of both closed and open-ended questions. The stakeholders interviewed were Safari Operators, Professional Hunters and Wildlife Rangers. The questionnaires were aimed at determining whether these perceptions were in line with the trophy quality trends observed from scientific data synthesized from the records. A One Way non-parametric analysis of variance (Kruskal Wallis) test, of the trophy quality data showed that from 2003 to 2013, there were significant annual variations for elephant and buffalo trophy quality (p < 0.01), while for lion, the variations were not significantly different (p > 0.395). The perceptions of stakeholders with more than four years hunting experience in SWRA corroborated the observed changes in trophy quality obtained from field measurements. The results revealed that elephant and buffalo trophy quality has significantly declined over the years. The study recommends that, where quantitative data on trophy quality are unavailable, information from experienced hunters can provide a useful insight on trophy quality trends which can help to make robust decision making processes for sustainable utilisation through consumptive tourism.
... Despite productivity usually being considered higher in populations with female-biased sex ratios (Caughley, 1977), it is increasingly acknowledged that the lack of adult males may alter reproduction, recruitment rates and eventually population dynamics (reviewed in Milner, Nilsen & Andreassen, 2007). Trophy hunting has been shown to reduce horn size with time (Coltman et al., 2003;Crosmary et al., 2013). However, offtakes from trophy hunting supposedly represent only a small fraction of the male segment in hunted populations (Cumming, 1989;Caro et al., 1998), so that the impact on population dynamics appears rather limited in polygynous ungulates (Mysterud, 2012). ...
... Robins, c. 1000 km 2 ; Sinamatella, c. 1000 km 2 ; Fig. 1), because their vegetation types and environmental conditions are similar to MSA (Tables 1 and 2; Ganzin et al., 2008;Peace Parks Foundation, 2009). We used 10-day Normalised Difference Vegetation Index (NDVI) images (resolution 1.2 × 1.2 km) available from 1986 to 2010 (Crosmary et al., 2013) (Skinner & Chimimba, 2005) and are hunted for trophies (Lindsey, Roulet & Romañach, 2007). They have distinct diets and body weight, but most are water dependent (except for warthog and giraffe; Table 3). ...
Article
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The persistence of large African herbivores in trophy hunting areas is still unclear because of a lack of data from long-term wildlife monitoring outside national parks. We compared population trends over the last 30 years in Hwange National Park, Zimbabwe, and the neighbouring Matetsi Safari Area where large herbivores were harvested at an average yearly rate of 2%. We investigated whether trophy hunting altered densities and the proportion of adult males in several large herbivore species. Large herbivores generally thrived as well, or even better, in the hunting areas than in the national park. The proportion of adult males did not differ between the two zones, except for species with higher harvest rates and proportionally more males harvested. Densities were not lower in the hunting areas than in the national park, except for elephant and impala. Large herbivores generally declined throughout the 30-year period in both zones, particularly selective grazers. This is probably because of their greater sensitivity to variation in rainfall compared with other herbivores. Rainfall indeed declined during the study period with droughts being particularly frequent during the 1990s. Browsers, mixed feeders and non-selective grazers generally declined less in the hunting areas than in the national park, possibly because of lower densities of natural predators and elephants outside the park. Our study highlighted that large herbivores may persist in trophy hunting areas as well as in national parks. When rigorously managed, trophy hunting areas may be relevant conservation areas for large herbivores, particularly under the current global decline of wildlife abundance across Africa.
... However, more effort needs to be put towards law enforcement as there has been a challenge of illegal hunting activities in some parts of Zimbabwe which has triggered much despondence and negative media framing [84,95,96]. A concerted effort towards monitoring animal populations, illegal off-takes, and trophy quality is critical for the sustainability of trophy hunting [97][98][99]. This information would provide essential scientific information required for adaptive management in lobbying and rebranding trophy hunting activities in these areas for the good of conservation [3]. ...
... Most of the experts viewed the quota setting process in Zimbabwe as overly relaying on opinions of stakeholders and not based on the monitoring data on population sizes thus compromising the sustainability of the process. Similarly there have been reports on the decline in trophy size of hunted species in some cases in Zimbabwe [97] as has also been the case with other regional countries, that is, South Africa [98,99,135], western Tanzania [136], and Zambia [137]. It is somehow believed that there seems to be a lack of implementation of age based harvesting strategies as required by the Zimbabwean policies on trophy hunting [58]. ...
Article
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Trophy hunting has potential to support conservation financing and contribute towards rural development. We conducted a systematic review of the Zimbabwean trophy hunting perspective spanning from pre-1890 to 2015, by examining the following: (1) evolution of legal instruments, administration, and governance of trophy hunting, (2) significance of trophy hunting in conservation financing and rural development, and (3) key challenges, emerging issues in trophy hunting industry, and future interventions. Our review shows that (i) there has been a constant evolution in the policies related to trophy hunting and conservation in Zimbabwe as driven by local and international needs; (ii) trophy hunting providing incentives for wildlife conservation (e.g., law enforcement and habitat protection) and rural communities’ development. Emerging issues that may affect trophy hunting include illegal hunting, inadequate monitoring systems, and hunting bans. We conclude that trophy hunting is still relevant in wildlife conservation and rural communities’ development especially in developing economies where conservation financing is inadequate due to fiscal constraints. We recommend the promotion of net conservation benefits for positive conservation efforts and use of wildlife conservation credits for the opportunity costs associated with reducing trophy hunting off-take levels and promoting non-consumptive wildlife use options.
... Trophy hunting targets the largest males or those with impressive horns, tusks, or antlers Milner-Gulland 1994, Milner et al. 2007). Even though it is generally restricted to a few individuals, where controls are lacking a high proportion of those individuals that qualify can be removed annually (Coltman et al. 2003, Crosmary et al. 2013. High levels of hunting are thus often not a sustainable use of wildlife resources (Baker 1997, Milner et al. 2007). ...
... Trophy hunting targets the largest males or those with impressive horns, tusks, or antlers Milner-Gulland 1994, Milner et al. 2007). Even though it is generally restricted to a few individuals, where controls are lacking, a high proportion of those individuals that qualify can be removed annually (Coltman et al. 2003, Crosmary et al. 2013. Selective harvesting may also have negative evolutionary consequences (Balme et al. 2010a. ...
Thesis
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Transfrontier conservation areas potentially play a key role in conserving biodiversity and promoting socioeconomic development. However, socio-political factors often affect their effectiveness in achieving biodiversity conservation and sustainable development objectives. Following a transdisciplinary approach, I assessed the challenges and opportunities in conserving and managing the African elephant (Loxodonta africana) population within the Greater Mapungubwe Transfrontier Conservation Area (GMTFCA) in Botswana, South Africa and Zimbabwe, southern Africa. The results showed that the current rate of offtake of bull elephant in the GMTFCA is unsustainable. At current rates of hunting, in fact, trophy bulls were predicted to disappear from the population in less than 10 years. Elephant densities were higher in South Africa and Botswana where the gross domestic product is higher. In addition, elephant densities were higher at sites where the proportion of agricultural land around them was the lowest and where vegetation productivity was the highest. Trophy hunting, as well as other localised human activities, also affected the distribution of elephant within sites, forcing them to trade-off between disturbance avoidance and the availability of food and water. While at the international level, a significant body of law and policy relevant to elephant conservation exists, I found that there was little cooperation among Botswana, South Africa and Zimbabwe, and a lack of implementation of these provisions on a national and trilateral level. Overall, this study confirmed that poverty was an important factor affecting elephant abundance at the country level, but highlighted that, at the site level, anthropogenic disturbance played a crucial role. A revision of the current hunting quotas within each country and the establishment of a single multi-jurisdictional (cross-border) management authority regulating the hunting of elephant is needed. Further, to reduce the impact of increasing human populations and agricultural expansion, the development of coordinated legislation and policies to improve land use planning, and the development of conservation corridors to link current protected areas, is needed. The issues regarding the management of this elephant population illustrate the significant challenges involved in achieving a comprehensive, consistent and effective implementation of a transboundary population approach. Southern African countries make an important contribution to elephant conservation and could soon become the last stronghold of elephant conservation in sub-Saharan Africa. Therefore, immediate actions are needed to reduce pressures from human activities in order to enhance the long-term persistence of the species.
... There are also evolutionary-scale consequences of the selective harvesting of trophy animals with particular heritable phenotypic traits [10,11]. This artificial selection typically leads to a rapid decline (within a few generations) in the desired trophy attributes within the hunted population. ...
... Such traits, including features such as body size, may be linked to other fitness-related attributes, such as physiological tolerances or disease resistance [10] and, thus, would lead to a decline in fitness. These selective pressures, which amount to domestication, vary as a function of hunting intensity, duration, and population size, and, thus, fluctuate among species [11]. Another form of domestication emerging from trophy hunting is the selective breeding for desirable traits in individuals, such as large manes in lions [12] or, in extreme cases, artificially selected color variants maintained by inbreeding [6]. ...
Article
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... The selective removal of 'desirable' morphological traits from individual populations through these processes is well-documented (Darimont et al., 2009). For example, hunting has led to a documented reduction in the tusk size of African elephants Loxodonta africana (Chiyo et al., 2015), horn size in sable antelope Hippotragus niger (Crosmary et al., 2013), and antler size in moose Alces alces (Schmidt et al., 2007) and deer (Allendorf & Hard, 2009). ...
Article
The artificial selection of traits in wildlife populations through hunting and fishing has been well documented. However, despite their rising popularity, the role that artificial selection may play in non‐extractive wildlife activities, for example, recreational feeding activities, remains unknown. If only a subset of a population takes advantage of human‐wildlife feeding interactions, and if this results in different fitness advantages for these individuals, then artificial selection may be at work. We have tested this hypothesis using a wild fallow deer population living at the edge of a capital city as our model population. In contrast to previous assumptions on the randomness of human‐wildlife feeding interactions, we found that a limited non‐random portion of an entire population is continuously engaging with people. We found that the willingness to beg for food from humans exists on a continuum of inter‐individual repeatable behaviour; which ranges from risk‐taking individuals repeatedly seeking and obtaining food, to shyer individuals avoiding human contact and not receiving food at all, despite all individuals having received equal exposure to human presence from birth and coexisting in the same herds together. Bolder individuals obtain significantly more food directly from humans, resulting in early interception of food offerings and preventing other individuals from obtaining supplemental feeding. Those females that beg consistently also produce significantly heavier fawns (300–500 g heavier), which may provide their offspring with a survival advantage. This indicates that these interactions result in disparity in diet and nutrition across the population, impacting associated physiology and reproduction, and may result in artificial selection of the begging behavioural trait. This is the first time that this consistent variation in behaviour and its potential link to artificial selection has been identified in a wildlife population and reveals new potential effects of human‐wildlife feeding interactions in other species across both terrestrial and aquatic habitats. Human‐wildlife feeding interactions are increasingly popular, yet the role that they may play in the artificial selection of behavioural traits in wildlife populations remains unexplored. This work begins to unravel the complex dynamics and impacts of these interactions, opening up new dimensions for human‐wildlife studies.
... We selected three most commonly hunted gregarious antelope species in Zimbabwe, namely impala, greater kudu and sable. These three species were chosen on the basis of their abundance and importance in the hunting industry, particularly sable (Crosmary et al. 2013). The density of the three species was measured during the study period for the hunting area (impala = 14.84/km 2 , kudu = 3.25/km 2 , sable = 4.26/km 2 ) and the tourist area (impala = 4.53/km 2 , kudu = 3.41/km 2 , sable = 1.91/km 2 ). ...
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Although being an important conservation tool in Africa, trophy hunting is known to influence risk perception in wildlife species, thus affecting the behaviour and fitness of most targeted species. We studied the effects of trophy hunting on the flight behaviour of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in two closed ecosystems, Cawston Ranch (hunting area) and Stanley and Livingstone Private Game Reserve (tourist area), western Zimbabwe. Using standardized field procedures, we assessed the flight behavioural responses of the three species in two seasons: non-hunting (December–March) and hunting (April–November) between March 2013 and November 2014. We tested the effect of habitat, group size, sex, season, start distance and alert distance on flight initiation distance using linear mixed models. Habitat, group size sex and alert distance did not have any effect on flight initiation distance for the three species. The three species were more alert and displayed longer flight initiation distances in the hunting area compared with the tourist area. Flight initiation distances for the three species were higher during the hunting season for the hunting area and low during the non-hunting season. Flight distances of the three species did not differ between the hunting area and the tourist area. We concluded that trophy hunting increased perceived risk of wild ungulates in closed hunting areas, whereas ungulates in non-hunting areas are less responsive and somehow habituated to human presence. Management plans should include minimum approach distances by tourists as well as establishing seasonal restrictions on special zones to promote species viability. Research aimed at integrating behavioural responses with physiological aspects of target species should be promoted to ensure that managers are able to deal with the behavioural trade-offs of trophy hunting at local and regional scale.
... For instance, when hunting pressure is low, some bighorn males with fast-growing horns could survive to ~7 years, the age at which large horns improve reproductive success (Coltman et al. 2002), mitigating the potential impact of artificial selection. Among trophy-hunted African ungulates, the decline in horn length was more pronounced for sable antelope (Hippotragus niger) than for impala (Aepyceros melampus) and greater kudu (Tragelaphus strepsiceros), likely because hunting pressure and trophy value were higher for sable than for the other two species (Crosmary et al. 2013). Despite the important ecological, evolutionary, and conservation implications of harvest selection (Festa-Bianchet 2003), however, we know little about how its impacts may vary in relation to harvest intensity. ...
Article
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Selective harvest may lead to rapid evolutionary change. For large herbivores, trophy hunting removes males with large horns. That artificial selection, operating in opposition to sexual selection, can lead to undesirable consequences for management and conservation. There have been no comparisons of long-term changes in trophy size under contrasting harvest pressures. We analyzed horn measurements of Stone's rams (Ovis dalli stonei) harvested over 37 years in two large regions of British Columbia, Canada, with marked differences in hunting pressure to identify when selective hunting may cause a long-term decrease in horn growth. Under strong selective harvest, horn growth early in life and the number of males harvested declined by 12% and 45%, respectively, over the study period. Horn shape also changed over time: horn length became shorter for a given base circumference, likely because horn base is not a direct target of hunter selection. In contrast, under relatively lower hunting pressure, there were no detectable temporal trends in early horn growth, number of males harvested, or horn length relative to base circumference. Trophy hunting is an important recreational activity and can generate substantial revenues for conservation. By providing a reproductive advantage to males with smaller horns and reducing the availability of desirable trophies, however, excessive harvest may have the undesirable long-term consequences of reducing both the harvest and the horn size of rams. These consequences can be avoided by limiting offtake.
... Evidence for artificial selection remains limited (Mysterud 2011). Unfortunately, time series of horn or antler size for harvested animals tend to be relatively recent, spanning at most a few decades (Mysterud et al. 2006, P erez et al. 2011, Crosmary et al. 2013. ...
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Many agencies and researchers use data from harvested animals to study temporal trends in phenotype. For large mammals, complete harvest records are typically only available for the past few decades, but records of the largest trophies have been collected for over a century. To examine whether record books and data from male bighorn sheep (Ovis canadensis) harvested under a minimum-curl regulation could detect temporal trends in horn length, we simulated populations of trophy-harvested male bighorn sheep where horn length was modeled to increase, remain stable, and decrease over time. All populations experienced a simulated harvest based on a minimum horn length, but only horns in the longest 5% of the initial distribution were entered in a fictional record book. We then assessed whether monitoring of harvested and “record” males detected temporal trends. Data from selective harvest underestimated declines and initially underestimated increases, but qualitatively detected both trends. Record-book entries, however, severely underestimated increases and did not detect declines, suggesting that they should not be used to monitor population trends. When these biases are taken into account, complete trophy harvest records can provide useful biological information.
... Trophy hunting can be an important component of many conservation programs (Leader-Williams, Smith, and Walpole 2001), and its economic revenues are partly driven by expectation of large trophy size (Festa-Bianchet and Lee 2009;Crosmary et al. 2013). In most of Canada, sport harvest of mountain sheep (Ovis canadensis and O. dalli) rams is based on a phenotypic definition of minimum horn curl that establishes whether or not a ram can be shot, with an unlimited number of permits available to resident hunters . ...
Article
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The potential for selective harvests to induce rapid evolutionary change is an important question for conservation and evolutionary biology, with numerous biological, social and economic implications. We analyze 39 years of phenotypic data on horn size in bighorn sheep (Ovis canadensis) subject to intense trophy hunting for 23 years, after which harvests nearly ceased. Our analyses revealed a significant decline in genetic value for horn length of rams, consistent with an evolutionary response to artificial selection on this trait. The probability that the observed change in male horn length was due solely to drift is 9.9%. Female horn length and male horn base, traits genetically correlated to the trait under selection, showed weak declining trends. There was no temporal trend in genetic value for female horn base circumference, a trait not directly targeted by selective hunting and not genetically correlated with male horn length. The decline in genetic value for male horn length stopped, but was not reversed, when hunting pressure was drastically reduced. Our analysis provides support for the contention that selective hunting led to a reduction in horn length through evolutionary change. It also confirms that after artificial selection stops, recovery through natural selection is slow. This article is protected by copyright. All rights reserved.
... While data from the various conservancy landscapes within the country indicate that populations in these areas have generally increased since the advent of Namibia's CBNRM program (Naidoo et al. 2011b), evidence on possible negative impacts of trophy hunting on wildlife populations in other parts of Africa (Packer et al. 2010;Lindsey et al. 2013a) means that this needs to be carefully monitored in Namibia to ensure the same does not happen. There have also been no assessments on how trophy size or quality in particular species may be changing over time, a concern that has been raised for trophy hunting in Africa (Crosmary et al. 2013), and which may result in undesirable genetic changes within hunted populations (Coltman et al. 2003). It is therefore critical that data on the size and quality of trophy exports be analyzed for Namibia's CBNRM program, to inform monitoring, evaluation, and management of the trophy hunting industry. ...
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Tourism and hunting both generate significant revenues for communities and private operators in Africa, but few studies have quantitatively examined the tradeoffs and synergies that may result from these two activities. Here, we evaluate financial and in-kind benefit streams from tourism and hunting on 77 communal conservancies in Namibia from 1998 to 2013, where community-based wildlife conservation has been promoted as a land-use that complements traditional subsistence agriculture. Across all conservancies, total benefits from hunting and tourism have grown at roughly the same rate, although conservancies typically start generating benefits from hunting within 3 years of formation as opposed to after 6 years for tourism. Disaggregation of data reveals the main benefits from hunting are income for conservancy management and meat to the community at large, while the majority of tourism benefits are salaried jobs at lodges. A simulated ban on trophy hunting significantly reduced the number of conservancies that were able to cover their operating costs, whereas eliminating income from tourism did not have as severe an effect. Given that the benefits generated from hunting and tourism typically begin at different times (earlier versus later, respectively) and flow to different segments of local communities, these two activities together can provide the greatest incentives for conservation. Notably, a singular focus on either hunting or tourism would likely reduce the value of wildlife as a competitive land-use option, and have serious negative implications for the viability of community-based conservation efforts in Namibia, and possibly in other parts of Africa.This article is protected by copyright. All rights reserved
... It can generate important revenue for landowners, contribute to national GDPs, and hunters may enforce anti-poaching and land management approaches that protect wildlife and natural habitat . Trophy hunting differs from other forms of harvest (e.g. for bushmeat or the medicinal trade) in that offtake can be regulated and is typically selective, focusing on individuals with attractive secondary sexual attributes such as large horns, tusks or manes (Crosmary et al., 2013;Whitman et al., 2004;Leader-Williams et al., 2001). However, when poorly managed (e.g. when there is consistent phenotypic selection, young animals are targeted or quotas are too high), trophy hunting can cause social disruption (Milner-Gulland et al., 2003), inheritance of undesirable traits (Coltman et al., 2003) and localized population declines (Packer et al., 2009;. ...
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The trophy hunting of African leopards Panthera pardus pardus may generate revenue to help foster their conservation. However, leopards are sensitive to hunting and populations decline if overharvested. The practice therefore requires careful management grounded in robust estimates of population density/status. Camera-trap surveys are commonly used to establish leopard numbers, and may guide harvest quotas. However, such surveys are limited over wide spatial scales and many African governments lack resources to implement them. In this thesis I explore the potential use of a harvest composition scheme applied to puma Puma concolor in North America, to monitor leopards. The method hinges on the susceptibility of different leopard cohorts to hunting and if this varies, then predictions can be made about harvest composition. Susceptibility is likely to be governed by space use, encounter rates with bait lures (a common method used to attract leopards to hunting hides) and hunter selectivity. Thus in this thesis I explore leopard susceptibility to these factors using a protected leopard population in northern Zululand, South Africa. In my first chapter I examine using scent lures in camera-trapping. Against a backdrop of a passive survey I show adult males, females and sub-adults are captured at similar rates compared to a passive survey using lures. The use of lures does not appear to violate closure assumptions or affect spatio-temporal patterning, but their use appears limited as density estimate precision is not improved. My second chapter examines ecological (likelihood of encountering a hunter) and anthropogenic (attractiveness to hunters) susceptibility of leopards to trophy hunting. I show that adult males are the most susceptible cohort to hunting (sub-adults least susceptible). I then take the incident rates from ecological and anthropogenic models and create a theoretical harvest composition using population parameters of protected leopards. My third data chapter departs from hunting susceptibility and examines determinants of leopard trophy package price across Africa. I show that factors such as trophy quality, outfitter leopard hunting reputation and hunt success have little impact on price determination. Instead, overall outfitter reputation and the number of charismatic species in a package are positively correlated with price. These results have important consequences on several sustainable leopard hunting schemes proposed in the literature.
... For instance, when hunting pressure is low, some bighorn males with fast-growing horns could survive to ~7 years, the age at which large horns improve reproductive success (Coltman et al. 2002), mitigating the potential impact of artificial selection. Among trophy-hunted African ungulates, the decline in horn length was more pronounced for sable antelope (Hippotragus niger) than for impala (Aepyceros melampus) and greater kudu (Tragelaphus strepsiceros), likely because hunting pressure and trophy value were higher for sable than for the other two species (Crosmary et al. 2013). Despite the important ecological, evolutionary, and conservation implications of harvest selection (Festa-Bianchet 2003), however, we know little about how its impacts may vary in relation to harvest intensity. ...
Article
Full-text available
Selective harvest may lead to rapid evolutionary change. For large herbivores, trophy hunting removes males with large horns. That artificial selection, operating in opposition to sexual selection, can lead to undesirable consequences for management and conservation. There have been no comparisons of long-term changes in trophy size under contrasting harvest pressures. We analyzed horn measurements of Stone's rams (Ovis dalli stonei) harvested over 37 years in two large regions of British Columbia, Canada, with marked differences in hunting pressure to identify when selective hunting may cause a long-term decrease in horn growth. Under strong selective harvest, horn growth early in life and the number of males harvested declined by 12% and 45%, respectively, over the study period. Horn shape also changed over time: horn length became shorter for a given base circumference, likely because horn base is not a direct target of hunter selection. In contrast, under relatively lower hunting pressure, there were no detectable temporal trends in early horn growth, number of males harvested, or horn length relative to base circumference. Trophy hunting is an important recreational activity and can generate substantial revenues for conservation. By providing a reproductive advantage to males with smaller horns and reducing the availability of desirable trophies, however, excessive harvest may have the undesirable long-term consequences of reducing both the harvest and the horn size of rams. These consequences can be avoided by limiting offtake.
... It can generate important revenue for landowners, contribute to national Gross Domestic Products (GDP), and hunters may enforce anti-poaching and land management approaches that protect wildlife and natural habitat [1]. Trophy hunting differs from other forms of harvest (e.g. for bushmeat or the traditional medicinal trade) in that offtake can be regulated and is typically selective, focusing on individuals with attractive secondary sexual attributes such as large horns, tusks or manes [3][4][5]. However, when poorly managed (e.g. when young animals are targeted or quotas are too high), trophy hunting can cause social disruption [6], the inheritance of undesirable traits [7] and localized population declines [8,2]. ...
Article
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Reliable data is fundamentally important for managing large carnivore populations, and vital for informing hunting quota levels if those populations are subject to trophy hunting. Camera trapping and spoor counts can provide reliable population estimates for many carni-vores, but governments typically lack the resources to implement such surveys over the spatial scales required to inform robust quota setting. It may therefore be prudent to shift focus away from estimating population size and instead focus on monitoring population trend. In this paper we assess the susceptibility of African leopards Panthera pardus to trophy hunting. This has management ramifications, particularly if the use of harvest composition is to be explored as a metric of population trend. We explore the susceptibility of different leopard age and sex cohorts to trophy hunting; first by examining their intrinsic susceptibility to encountering trophy hunters using camera-traps as surrogates, and second by assessing their extrinsic susceptibility using photographic questionnaire surveys to determine their attractiveness to hunters. We show that adult male and female leopards share similar incident rates to encountering hunters but adult males are the most susceptible to hunting due to hunter preference for large trophies. In contrast, sub-adult leopards rarely encounter hunters and are the least attractive trophies. We suggest that our findings be used as a foundation for the exploration of a harvest composition scheme in the Kwazulu-Natal and Limpopo provinces where post mortem information is collected from hunted leopards and submitted to the local provincial authorities.
... The conservation status of sable after 2001 in the region is unclear, because recent aerial data are lacking. Considering the economic crisis, land use change and human population increase around HNP since 2000 (Central Statistical Office, 1992, 2002Coltart, 2008), however, we suspect that the sable population has continued to decline (Crosmary et al., 2012(Crosmary et al., , 2013. ...
Article
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Land use has major effects on wildlife conservation. We studied variations of sable antelope Hippotragus niger densities between 1990 and 2001 in comparison with various land uses in and around Hwange National Park, Zimbabwe. Trends of other ungulates, including elephant Loxodonta africana, were examined simultaneously, because sable may be sensitive to forage and apparent competition and to high elephant densities. Sable densities declined in the whole region, very likely because of adverse rainfall conditions. Densities were constantly higher in the hunting areas and forestry lands than in the national park. Interestingly, elephant densities showed the opposite, with higher densities in the national park than in the adjacent areas. Whether these results reflect a negative effect of high elephant numbers on sable must still be tested directly. Likewise, while habitat characteristics and lion predation did not appear responsible for the higher sable densities outside the national park, they could not be discounted as an influence on the differing sable densities in different land‐use areas. It is clear, however, that high protection status is not always sufficient to ensure adequate conservation of flagship species. We therefore call for further investigations of ecological interactions within protected areas.
... Such harvesting can cause changes in the distribution of phenotypic traits within target populations, often with undesirable biological and economic consequences. For example, selective harvesting has been linked to declines in the size of trophy horns in two antelope species in Zimbabwe (2) and of antlers in red deer (Cervus elaphus) in Europe (3,4), as well as to earlier maturation in some fish species (5). However, the extent to which these changes are the result of ecological or evolutionary mechanisms has been much debated (1). ...
Article
Selective harvesting of animals is widespread throughout the marine, freshwater, and terrestrial environments and affects a diverse list of species, including fish, mammals, birds, and reptiles (1). Such harvesting can cause changes in the distribution of phenotypic traits within target populations, often with undesirable biological and economic consequences. For example, selective harvesting has been linked to declines in the size of trophy horns in two antelope species in Zimbabwe (2) and of antlers in red deer (Cervus elaphus) in Europe (3, 4), as well as to earlier maturation in some fish species (5). However, the extent to which these changes are the result of ecological or evolutionary mechanisms has been much debated (1). In PNAS, Traill et al. (6) approach this question from a novel angle by developing stochastic two-sex integral projection models (IPMs) capable of differentiating between the ecological and evolutionary effects of selective harvest. Their finding that evolutionary mechanisms contribute relatively little to observed changes in the body mass of bighorn sheep (Ovis canadensis) is an intriguing contribution to the debate over the evolutionary consequences of selective offtake, contradicting earlier studies (7). In addition, Traill et al. (6) suggest that their method could be adopted more widely to allow wildlife managers and conservation practitioners to incorporate the potential evolutionary effects of selective harvesting into their management planning. Here, we explore this suggestion by discussing key challenges that would need to be addressed to translate the approach by Traill et al. (6) from a purely biological model to an effective management model, focusing particularly on issues of data availability and the incorporation of different forms of uncertainty.
... Temporal and spatial trophy quality changes may have adverse effects on the sustainability of the hunting industry (von Brandis and Reilly, 2007). Declines in trophy quality of preferred wildlife species have been reported in sub-Saharan Africa (Crosmary et al., 2013;Loveridge et al., 2009;Nuzzo and Traill, 2013;von Brandis and Reilly, 2008;Wilfred, 2012). Nonetheless, Wilfred (2012) argues that negative trends in trophy quality will certainly illicit similar trends in the economy since the trophy hunting market aligns itself with those countries producing superior trophy animals. ...
Article
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Although the contribution of trophy hunting as a conservation tool is widely recognised, there is perpetual debate and polarization on its sustainability. This review integrates five themes mostly considered in isolation, as independent research fields in wildlife conservation: (1) trophy quality and population ecology of hunted species, (2) behavioural ecology of hunted populations and associated avoidance mechanisms, (3) physiological stress in hunted populations, (4) genetic variability and desirable traits, and (5) socio-economic imperatives in wildlife conservation. We searched for articles on search engines using specific key words and found 350 articles from which 175 were used for this review under five key themes. Population and trophy quality trends of commonly hunted species seem to be declining in some countries. Elevated hunting pressure is reported to influence the flight and foraging behaviour of wildlife thus compromising fitness of hunted species. Selective harvesting through trophy hunted is attributed to the decline in desirable phenotypic traits and increased physiological stress in most hunted species. Though it provides financial resources need for conservation in some countries, trophy hunting works well in areas where animal populations are healthy and not threatened by illegal harvesting and other disturbances. There remains much polarity on the sustainability of trophy hunting in modern-day conservation. More research need to be conducted across the five themes examined in this review for broader analytical analysis and comparison purposes. A new research agenda is needed regarding wildlife sustainable use principles and their sustainability and acceptability in modern-day conservation.
... Without any doubt, imposed restrictions on the huntable age of individuals bearing large antlers preserve animals until full trophy maturity. This is confirmed by the size of trophies and is in-fluenced by the hunting strategies employed (Martínez et al. 2005, Mysterud 2011, Crosmary et al. 2013. As a conclusion, the hunter's influence on phenotypic characters is considerable (Allendorf & Hard 2009). ...
Article
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With antlers valuated as trophies, ungulates experience high pressures due to selective hunting. The response of the population differs depending on the type of hunting strategy used, and trophies serve as a suitable proxy to answer this question. For example, unrestricted trophy or leisure hunting results in a diminishing quality of trophies. We evaluated the effect of the applied hunting strategy on European roe deer (Capreolus capreolus) antler size in Lithuania, Latvia and Estonia between 2006 and 2011. With the aim of preserving good quality bucks up to 5 years of age, compensatory hunting (culling) is obligatory in Lithuania. To the north, in the other two Baltic countries, roe deer buck are hunted with no age limit. Based on nonparametric tests and forward stepwise discriminant function analysis of antler morphometric characters, Lithuanian roe deer antlers were found to be significantly larger (about 40 % by mean weight and volume for the 35 biggest trophies). We conclude that bucks in Latvia and Estonia are hunted out before they reach trophy maturity (5-7 years). The antlers of fast growing bucks in the age of 3-4 years are almost as big, so they are untimely eliminated from the population. We recommend extending the preservation period of healthy roe deer buck to 6 years of age, giving hunters the possibility to estimate their age not solely on antler size, but also on other body characters.
... Headgear is thought to play a primary role in sexual selection, where larger horn and antler size can result in higher reproductive success (Monteith et al. 2013). Headgear size and growth rate have also been linked to body condition, reproduction, dominance and genetic diversity (Crosmary et al. 2013, Festa-Bianchet et al. 2014, Larue et al. 2021) and ...
Article
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Potential negative artificial selection on horn size is a concern for many harvested ungulates. The mountain goat (Oreamnos americanus) has distinct black horns, but targeting animals based on horn size in the field can be challenging. We analyzed over 23,000 horn records that included base circumference and total length, from which we also derived horn volume, from mountain goats harvested in Alaska, British Columbia, and the Northwest Territories from 1980 to 2016. We tested 3 potential drivers of horn size variation: geographical location, environmental conditions, and artificial selection. We found no support for a latitudinal effect with surprisingly little variation across the sampling distribution. The Pacific Decadal Oscillation had the largest effect outside age in the model, suggesting a role of climate in shaping variation. Mountain goats harvested closer to roads had larger horns, indicating that ease of access might allow hunters to be more selective, though the effect size was small. Our findings reinforce the value of accurate and complete record keeping on horn size, age, and sex of harvested animals, and highlight the importance of explicitly considering climate and accessibility when devising management strategies for the mountain goat. We explored possible climatic, geographic and anthropogenic drivers of variation in horn size of the North American mountain goat over the past 40 years. We recommend continued and transparent record keeping for all harvested mountain goats by government authorities.
... Contrastingly, hunting pressures can favor the survival of "lessdesirable" species, or individuals within a species with less-appealing characteristics than another member of its group. For instance, Crosmary et al. (2013) investigated the influence of trophy hunting on horn size for antelope in Africa. Longer horned individuals were preferred by hunters resulting in a relatively high hunting pressure expended on sable antelopes (Hippotragus niger) along with a higher valued price tag, compared to a relatively low hunting pressure in impalas (Aepyceros melampus) and greater kudus (Tragelaphus strepsiceros). ...
Chapter
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... A specific example of this is the white rhino itself, of which the population has increased drastically due to private ownership and trophy hunting (Leader- Williams et al., 2005;Roe & Cremona, 2016). However, when poorly managed trophy hunting can have deleterious genetic effects, alter the age/sex structures or even result in population declines of target species (Crosmary et al., 2013;Loveridge et al., 2007;Milner et al., 2007;Packer 2.8 Supplementary materials 33 et al., 2011). Furthermore, body parts of poached animals can be trafficked by being concealed as trophies, which has happened with rhino horns from South Africa (Ayling, 2013;Cota, 2013;Rademeyer, 2016). ...
... The impact of hunting on wildlife populations is complex and hard to quantify (Milner et al., 2007;Selier et al., 2016). Concerns have already been raised on how TH may jeopardize the genetic integrity of populations (Coltman et al., 2003;Crosmary et al., 2013) and reproductive success (Milner et al., 2007;Packer et al., 2009;Selier et al., 2016). While there are examples of effective quotas set by local communities through programs like Zimbabwe's Communal Areas Management Programme for Indigenous Resources (CAMPFIRE) (Frost & Bond, 2008), TH approach alone was not adequate strategy to contribute to sustainable control of wildlife populations (Teichman et al., 2016). ...
Article
Trophy hunting (TH) tourism plays an important and often controversial role in wildlife conservation and community livelihood in many African countries. Despite its potential social and economic benefits, TH can have a negative impact among the locals and pose critical challenges in governance. However, research on the local community perspective of TH and how it is linked to empowerment of locals and wildlife conservation in Namibia remains limited. Therefore, to address these gaps, our study explores how communities of Namibia’s Bwabwata National Park perceive TH and how TH supports or hinders empowerment of local communities and their relationship with wildlife. Through semi-structured interviews with community members, this study elucidates the economic benefits and inequities, cultural impacts from lack of traditional hunting, perceived relationship to poaching, and limitations of governance and distrust among stakeholders. This research innovatively applies empowerment theory to TH tourism and thus, can strengthen and inform sound governance and sustainable practices of TH at local, national, and international levels by providing the local perspective that has largely been absent from the TH debate.
... Although the killing of the African Lion, 'Cecil' in 2015, outside Hwange National Park, Zimbabwe, initiated global mass outrage, trophy hunting has always been controversial from a range of ecological, ethical and cultural perspectives (Adams, 2009). While the potential negative impacts on population genetics, structure and demographics are well understood (Trenkle, 2001;Crosmary et al., 2013;Wielgus et al., 2013), the killing of animals for entertainment and for body parts in exchange for high-fees by wealthy individuals, usually from outside the area where the hunting occurs is seen as both primitive and cruel by the growing animal rights and welfare movement (MacDonald et al., 2016). Furthermore, this practice is often described as an anachronism redolent of medieval times that serves to reinforces inequities between the rights of rich and poor in rural areas (MacMillan, 2004). ...
Article
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The use of trophy hunting as a wildlife management option has been a highly controversial topic, especially in southern Africa, but trophy hunting has historically also taken place also throughout Asia. In China, trophy hunting was the topic of intense public discussion more than a decade ago, leading ultimately to the suspension of this practice in 2006. Yet, this debate was dominated by urban voices, with no formal consultation of rural populations from minorities such as the Tibetan herders who previously benefited financially from commercial trophy hunting acting as guides and who are also concerned about the negative impact of rising blue sheep numbers on livestock grazing. We used a discrete choice experiment econometric method to better understand the trade‐offs made by both urban and rural populations across China in relation trophy hunting as a rural development and wildlife management tool. We find that trophy hunting is supported by the majority of rural residents but opposed by most urban residents, although there is heterogeneity within both these groups. We recommend that policy‐making in this realm should be informed by a better understanding of the preferences of different stakeholders, including the local people who bear the costs of living with wildlife. Islands and coastal environments are increasingly threatened by multiple stressors including rising sea level, invasive species, and human development. By surveying rodents in the Lower Keys, FL, we show that endangered silver rice rats use the tidally inundated mangrove forests fringing these islands, whereas invasive black rats are more likely to occur in upland environments. As such, rising sea level may benefit this endangered species, but only if human development is limited.
... Coltman et al. (2003) showed that hunting bighorn trophy rams based on their heritable traits (specifically body and horn size) results in smallerhorned, lighter rams and fewer trophies in North America. Similar effects have been observed on impalas, greater kudus and sable antelopes in Africa (Crosmary et al., 2013;Muposhi et al., 2016), as well as Cape buffalo and elephants (Muposhi et al., 2016). Additionally, skewed sex ratios and age structures due to selective harvesting of large mammals may cause rapid evolution, in addition to other adverse evolutionary outcomes (Aryal et al., 2015;Mysterud, 2011 ...
Article
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1. Ethical concerns are at the heart of the ongoing debate on trophy hunting; however, so far, most studies have addressed the issue from a single ethical perspective. These studies, approaching the subject from different ethical perspectives, have reached different conclusions. For instance, those who support trophy hunting as a conservation strategy usually adopt a utilitarian perspective, while those who adopt a deontological perspective usually oppose it. 2. The analysis presented in this paper challenges the ethical justification of trophy hunting based on a utilitarian perspective, and it also suggests that trophy hunting is problematic from the perspectives of both deontology and virtue theory. 3. This paper supports a version of Bryan Norton's ‘convergence hypothesis’ (Norton, 1991). Although holism and anthropocentrism in environmental ethics are usually presented as fundamentally opposed views, Norton argued that their conclusions for policy converge, at least when a sufficiently broad and long-range view of human interests are considered. 4. Analogously, this paper proposes that, regarding trophy hunting, the implications of three major traditional perspectives in ethics (i.e. utilitarianism, deontology and virtue theory) may converge in opposition to the practice of trophy hunting. 5. The final section of this paper recommends some ways authorities and policymakers can address these ethical concerns and presents a view of the future.
... Nature reserves, or protected areas, should have the potential to restore sources of individuals that are not affected by harvest selection. In trophy-hunted bighorn rams (Ovis canadensis), individuals harvested near protected areas in Canada had larger average horn size compared to rams shot far from protected areas (Pelletier, Festa-bianchet, Jorgenson, Feder, & Hubbs, 2014), and in Zimbabwe, horn size of impala (Aepyceros melampus) decreased with distance from a national park (Crosmary et al., 2013). In oceans and coastal areas worldwide, marine protected areas (MPAs) are increasingly being implemented to restore depleted populations, improve ecosystem health and benefit fisheries through spillover effects (Hastings & Botsford, 2003;Pendleton et al., 2018). ...
Article
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Marine protected areas (MPAs) are increasingly implemented worldwide to maintain and restore depleted populations. However, despite our knowledge on the myriad of positive responses to protection, there are few empirical studies on the ability to conserve species’ mating patterns and secondary sexual traits. In male European lobsters (Homarus gammarus), the size of claws relative to body size correlates positively with male mating success and is presumably under sexual selection. At the same time, an intensive trap fishery exerts selection against large claws in males. MPAs could therefore be expected to resolve these conflicting selective pressures and preserve males with large claws. We explored this hypothesis by contrasting claw size of males and females in three pairs of MPAs and nearby fished areas in Southern Norway. By finding that male lobsters have up to 8 % larger claws inside MPAs compared to similarly sized males in fished areas, our study provides evidence that MPAs rescue a secondary sexual trait. Recovery from harvest selection acting on claws is the most likely explanation, however, the higher abundance of lobster inside MPAs does not rule out a plastic response on claw size due to increased competition. Regardless of the underlying cause, our study demonstrates (1) the value of protected areas as a management tool for mitigating fishery‐induced evolution, and (2) that MPAs help maintaining the scope for sexual selection in populations with vulnerable life‐histories and complex mating system.
... Evolutionary change would be more rapid if both sexes were selectively targeted as is unfortunately the case for African elephant (Loxodonta africana) populations in some countries (Selier et al. 2014). When harvesting is less selective, or coupled with habitat change, the evolutionary consequences of selective harvesting may be harder to detect (Garel et al. 2007, Crosmary et al. 2013, Monteith et al. 2013, Rivrud et al. 2013). Our work does not tackle the ethics or ecological consequences of trophy hunting, nor do we account for potential economic benefits of hunting for local communities, whether these be in Canada (Hurley et al. 2015) or in the developing world (Lindsey et al. 2007). ...
Article
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Some ecologists suggest that trophy hunting (e.g., harvesting males with a desirable trait above a certain size) can lead to rapid phenotypic change, which has led to an ongoing discussion about evolutionary consequences of trophy hunting. Claims of rapid evolution come from the statistical analyses of data, with no examination of whether these results are theoretically plausible. We constructed simple quantitative genetic models to explore how a range of hunting scenarios affects the evolution of a trophy such as horn length. We show that trophy hunting does lead to trophy evolution defined as change in the mean breeding value of the trait. However, the fastest rates of phenotypic change attributable to trophy hunting via evolution that are theoretically possible under standard assumptions of quantitative genetics are 1–2 orders of magnitude slower than the fastest rates reported from statistical analyses. Our work suggests a re-evaluation of the likely evolutionary consequences of trophy hunting would be appropriate when setting policy. Our work does not consider the ethical or ecological consequences of trophy hunting.
... Trophy hunting targets the largest males or those with impressive horns, tusks, or antlers (Ginsberg andMilner-Gulland 1994, Milner et al. 2007). Even though it is generally restricted to a few individuals, where controls are lacking a high proportion of those individuals that qualify can be removed annually (Coltman et al. 2003, Crosmary et al. 2013. High levels of hunting are thus often not a sustainable use of wildlife resources (Baker 1997, Milner et al. 2007). ...
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Trophy hunting of African elephant is often implemented as an income generator for communities surrounding protected areas. However, the sustainability of hunting on elephant populations, especially with regards to international cross-border populations has not previously been evaluated. We assessed the effects of trophy hunting on the population dynamics and movements of elephant in the Greater Mapungubwe Transfrontier Conservation Area, which is spread across the junction of Botswana, South Africa, and Zimbabwe. Currently, no common policy exits in quota setting for cross-border species, and each country determines their own quota based on limited data. Using VORTEX, we determined the sustainability of current quotas of elephant off-take under different ecological and hunting scenarios. We used distribution data from 6 aerial surveys and hunting data per region to determine the disturbance effect of hunting on bulls and breeding herds separately. Hunting of bulls had a direct effect in reducing bull numbers but also an indirect effect due to disturbance that resulted in movement of elephants out of the areas in which hunting occurred. The return interval was short for bulls but longer for females. Only a small number of bulls (<10/year) could be hunted sustainably. At current rates of hunting, under average ecological conditions, trophy bulls will disappear from the population in less than 10 years. We recommend a revision of the current quotas within each country for the Greater Mapungubwe elephant population, and the establishment of a single multi-jurisdictional (cross-border) management authority regulating the hunting of elephant and other cross-border species. © 2013 The Wildlife Society
... Among ungulates, the potential evolutionary consequences of harvest by humans can be assessed by evaluating temporal changes in antler, horn, or pronghorn size (hereafter, antlers and horns) because those traits are heritable, linked to reproductive success, and are often the target of selective harvest (Crosmary et al. 2013;Monteith et al. 2013;Festa-Bianchet et al. 2014;Pigeon et al. 2016). Assessing changes in size over time is difficult in long-lived species because changes in allele frequencies can take decades to manifest as a detectable phenotypic change; moreover, long-term data on phenotypic characteristics are often lacking (Hundertmark et al. 1998). ...
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Long-term datasets are becoming increasingly important for assessing population-and species-level responses to a changing environment. Programs that record morphological measurements of horns, antlers, and pronghorns were established in the early-to mid-20th century to collect biological information about animals that possess large horns, antlers, or pronghorns, which could be used to assess the effectiveness of conservation efforts for large mammals in North America. The general relevance of record books has been questioned because of the minimum size requirements for inclusion in a record book, which may mask trends when changes in the population occur. We compared trends in size of antlers, horns, and pronghorns through time using records from three records programs with different minimum size requirements to evaluate the influence of entry requirements on temporal trends. We also investigated whether horn, antler, or pronghorn size affected the probability of specimens being submitted to a records program. Only two of 17 categories exhibited less-pronounced trends in the record book with the highest size requirements for entry, and in two categories trends were more pronounced. Although societal interest in submitting eligible specimens increased slightly over time in one of six categories, the probability of voluntary entry was largely random and not affected by year of harvest or size of specimen. In contrast to previous criticisms, trends in record books should not be expected to represent the size of all males within a population. Instead, our evaluation indicates that the records programs we examined can provide a useful resource for assessing long-term changes in phenotypic characteristics of ungulates, but importantly, they represent the respective range of sizes within which each program collects data.
... Trophy quality is a function of dimensions and the aesthetic appearance of the trophy depending on the species [13]. Over time, some negative effects of trophy hunting on the desirable phenotypic traits of selected wildlife species seem to be evident [14]. Loss of desirable phenotypic traits (i.e., horn or tusk size) with increasing trophy hunting pressure has been reported in some wildlife species [15]. ...
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Developing harvest management strategies in designated hunting areas requires systematic and robust monitoring. We assessed the trophy size, quota utilization, and distribution of kill sites of African elephant, Cape buffalo, greater kudu, and leopard for the period 2007-2014 in Malapati Safari Area, southeast Zimbabwe. Trophy sizes for African elephant significantly increased over time albeit being below the expected minimum Safari Club International (SCI) score. Cape buffalo trophy sizes declined significantly over time but were not different from the SCI minimum score. However, greater kudu trophy sizes were higher than the SCI minimum score despite being constant over time. Leopard trophy sizes were higher than the SCI minimum score and increased with time. Quota utilization for African elephant and Cape buffalo increased while that of greater kudu and leopard did not change between 2007 and 2014. Some kill sites, in particular, for the African elephant and Cape buffalo, were within the buffer area with the state protected area, i.e., Gonarezhou National Park. Increased hunting pressure likely leads to poor trophy quality and hunting within the protected buffer areas. In contrast, effective adherence to hunting ethics and scientifically and conservatively set quotas largely does not compromise the trophy quality of harvested species. The observed trophy size patterns and kill sites distribution suggest the possible existence of source and sink dynamics of trophy species occurring in a protected area complex within the Zimbabwe’s component of the Greater Limpopo Transfrontier Park. To ensure sustainable trophy hunting in the study area and similar ecosystems the following are recommended: (i) scientifically robust, adaptable, and participatory quota setting process, (ii) enhanced adherence to good practice in terms of ethical hunting conduct, and (iii) development of a robust hunting monitoring system covering all elements of hunting for adaptive wildlife management.
... This is supported by a population average (42.43") above the RW trophy standard for bulls between 48 and 54 months in the present study, comparable with the results reported by Crosmary et al. (2013) on trophy-hunted sable in the Matetsi Safari area of Zimbabwe. The assumption of inferior performance of captive bred herds is based on the possible effects of inbreeding in small populations (Scribner et al., 1989;Fitzsimmons et al., 1995), but the evaluation of these herds showed a low average level of inbreeding (0.0043). ...
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Much of the economic value of wildlife can be attributed to horn size, which is an important trait for trophy hunters. The main objective of the study was to estimate genetic parameters for the economically important horn traits of sable antelope that are currently being measured in the South African industry. To date, no quantitative genetic analysis has been done for any traits in sable antelope. The total number of records included in the evaluation were n = 1713 for horn length (SHL), n = 1503 for circumference (SHC), n = 1486 for tip to tip (SHTT), n = 1505 for tip length (SHT), and n = 1447 for rings (SHR). Males and females were considered separately in six-month age clusters. A Markov chain Monte Carlo (MCMC) multi-trait analysis was used to estimate (co)variance parameters for the horn traits. The results indicate a sex effect for all the traits and suggest that it is not economically viable to measure horn length of either sex after 54 months old. The horns of females are on average 40% shorter compared with bulls at maturity. Continuous horn growth throughout the lifetime of sable is suggested by the formation of ring posts, but is often masked by horn attrition and inadequate measuring techniques. An inbreeding coefficient of 0.0043 suggests adequate genetic diversity in the studied population. Heritability estimates of horn traits varied from 0.085 to 0.52, while genetic correlations ranged from 0.1 to 0.6 with the highest correlation being found between horn length and tip to tip. Further studies are recommended to confirm these results.
... Horn size appears to play a limited role in mating success of male chamois (Corlatti et al. 2015). An analysis of 3 species of African antelope within the same hunting area provided inconsistent results, with horn size increasing over time in one species and decreasing in another (Crosmary et al. 2013). Intense poaching pressure may have selected for smaller tusks in African elephants (Loxodonta africana- Chiyo et al. 2015), but age was not directly included in the analysis and the case for evolutionary change is weakened by the lack of clear evidence that poachers spare elephants with smaller tusks. ...
Article
Intense selective harvest of large mammals who carry the largest weapons may lead to an evolutionary shrinkage of those weapons. Currently, evidence suggesting evolutionary effects of harvest is limited to a few species of Bovidae and only 1 study has obtained data indicating a genetic effect. To have an evolutionary impact, harvest must be intense, persistent over time, similar over a large area without an effective source of unselected immigrants, and remove large individuals before they have a chance to breed. Many current harvest schemes do not fulfill all of these requirements, and they are unlikely to cause evolution. Before changes in weapon size over time are attributed to evolution, potential environmental sources of change, mainly density and climate, must be considered. We suggest that the role of weapon size in determining reproductive success, especially in interaction with male age, will determine whether or not intensive selective harvests may have evolutionary consequences. Age at harvest is a very important variable to consider. Changes in age structure over time may reveal underlying changes in harvest pressure or selectivity. A lack of data hampers our ability to assess the potential evolutionary effects of selective hunting. We provide a list of research hypotheses required to advance our ability to assess the evolutionary sustainability of current management practices.
... Matetsi safari area (18°22.760′S, 25°52.353′E) is a relatively large protected area that promotes trophy hunting (~3,000 km 2 ) and was established in the early 1970s for trophy hunting (Crosmary et al., 2013;Muposhi et al., 2016) and photography. It is sub-divided into blocks called units. ...
... An analysis of hunting quotas for SWRA showed that there is need for reduced quotas so as to promote sustainable hunting off-takes. Reduced hunting pressure due to a reduction in issued quotas may allow trophy animals to grow quality trophies before being harvested [9]. Fixed quotas are likely to encourage utilisation of the entire portion of the quota regardless of sustainability hence affecting the future of wild game animals' trophy hunting industry [5]. ...
Article
Intra- and intersexual selection drives the evolution of secondary sexual traits, leading to increased body size, trait size and generally increased reproductive success in bearers with the largest, most attractive traits. Evolutionary change through natural selection is often thought of primarily in terms of genetic changes through mutations and adaptive selection. However, this view ignores the role of the plasticity in phenotypes and behaviour and its impact on accelerating or decelerating the expression of sexually selected traits. Here, we argue that sudden changes in selection pressures (e.g. predation pressure) may cause a cascade of behavioural responses, leading to a rapid change in the size of such traits. We propose that selective removal of individuals with the most prominent traits (such as large antlers or horns in male ungulates) induces behavioural changes in the surviving males, leading to a reduction in the growth of these traits (phenotypic expression). To test this idea, we used an individual-based simulation, parametrized with empirical data of male bighorn sheep, Ovis candensis. Our model shows that the expression (phenotype, not genotype) of the trait under selection (here horn size) can be negatively impacted, if the biggest, most dominant males in the population are removed. While the selective removal of prime males opens breeding opportunities for younger, smaller males, we predicted that it would come at the expense of growth and maintenance. As predicted, we observed a rapid decline in average male horn length in our model. We argue that this decline happens because smaller males, instead of allocating energy into growth, divert this energy towards participation in mating activities that are typically exclusively available to prime males. While our model deals with ecological life-history trade-offs, it cannot predict evolutionary outcomes. However, this nongenetic mechanism is important for the understanding of evolutionary processes because it describes how heritable traits can rapidly change because of behavioural plasticity, long before any genetic changes might be detectable.
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This chapter focuses on antelopes, a group of species within the family Bovidae. It focuses on Africa since this is where most research on trophy hunting of ungulates has been carried out. The chapter describes purely recreational hunting which is more common among local people in Europe, North America, and Australia. It also reviews more recent research on trophy hunting with a focus on the ecological and evolutionary effects of hunting on target species, and on the socio-economic drivers of trophy hunting and its impact on poverty alleviation. The chapter then considers the ways to improve the sustainability of trophy hunting. If sustainability can be improved through an understanding of the holistic nature of the hunting system, then the case for trophy hunting as a conservation tool can be considered based on its intrinsic merits, rather than with respect to issues surrounding its implementation in practice.
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Some ecologists suggest that trophy hunting (e.g. harvesting males with a desirable trait above a certain size) can lead to rapid phenotypic change, which has led to an ongoing discussion about evolutionary consequences of trophy hunting. Claims of rapid evolution come from the statistical analyses of data, with no examination of whether these results are theoretically plausible. We constructed simple quantitative genetic models to explore how a range of hunting scenarios affects the evolution of a trophy such as horn length. We show that trophy hunting does lead to trophy evolution defined as change in the mean breeding value of the trait. However, the fastest rates of phenotypic change attributable to trophy hunting via evolution that are theoretically possible under standard assumptions of quantitative genetics are 1 to 2 orders of magnitude slower than the fastest rates reported from statistical analyses. Our work suggests a re-evaluation of the likely evolutionary consequences of trophy hunting would be appropriate when setting policy. Our work does not consider the ethical or ecological consequences of trophy hunting.
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Human harvests can unwittingly drive evolution on morphology and life history, and these selective effects may be detrimental to the management of natural resources. Although theory suggests that harvest refuges, as sources of unselected animals, could buffer the effects of human exploitation on wild populations, few studies have assessed their efficiency. We analyzed records from >7000 trophy bighorn rams (Ovis canadensis) harvested in Alberta, Canada, between 1974 and 2011 to investigate if the movement of rams from refuges toward harvested areas reduced the effects of selective harvesting on horn size through phenotypic rescue. Rams taken near refuges had horns on average about 3% longer than rams shot far from refuges and were slightly older, suggesting migration from refuges into hunted areas. Rams from areas adjacent to and far from harvest refuges, however, showed similar declines in horn length and increases in age at harvest over time, indicating a decreasing rate of horn growth. Our study suggests that the influx of rams from refuges is not sufficient to mitigate the selective effects of sheep trophy harvest. Instead, we suggest that selective hunting of highly mobile animals may affect the genetic structure of populations that spend part of the year inside protected areas.
Article
Simple Summary: Trophy hunting and mass tourism were introduced to Khunjerab National Park, northern Pakistan to generate income for the community and help conserve and sustain the ecosystem in the region. These initiatives have provided economic benefits, but only at the cost of other environmental problems, as both trophy hunting and mass tourism have resulted in various ecological issues. Trophy hunting has not been based on scientific population data and has thus not helped increase numbers of wild ungulates or wild carnivores. Although mass tourism has increased enormously in this region, it has damaged the ecosystem through pollution generation and negatively impacted wildlife. We suggest that trophy hunting should be stopped, and mass tourism should be shifted to ecotourism as a sustainable solution to help improve the ecosystem, while generating income for the local community. Further studies are required to investigate ecotourism as a potential mitigation measure for the conservation issues in this region. Abstract: Trophy hunting and mass tourism are the two major interventions designed to provide various socioeconomic and ecological benefits at the local and regional levels. However, these interventions have raised some serious concerns that need to be addressed. This study was conducted in Khunjerab National Park (KNP) with an aim to analyze comparatively the socioeconomic and ecological impacts of trophy hunting and mass tourism over the last three decades within the context of sustainability. Focus Group Discussions (FGDs) with key stakeholders and household interviews were conducted to collect data on trophy hunting and mass tourism, and on local attitudes towards these two interventions in and around KNP. The results revealed that 170 Ibex (Capra sibirica) and 12 Blue sheep (Pseudois nayaur) were hunted in the study area over the past three decades, and trophy hunting was not based on a sustainable harvest level. Trophy hunting on average generated USD 16,272 annual revenue, which was invested in community development. However, trophy hunting has greatly changed the attitudes of local residents towards wildlife: a positive attitude towards the wild ungulates and strongly negative attitude towards wild carnivores. In addition, trophy hunting has reduced the availability of ungulate prey species for Snow leopards (Panthera uncia), and consequently, Snow leopards have increased their predation on domestic livestock. This has, in turn, increased human-snow leopard conflict, as negative attitudes towards carnivores result in retaliatory killing of Snow leopards. Furthermore, according to official record data, the number of tourists to KNP has increased tremendously by 10,437.8%, from 1382 in 1999 to 145,633 in 2018. Mass tourism on average generated USD 33,904 annually and provided opportunities for locals to earn high incomes, but it caused damages to the environment and ecosystem in KNP through pollution generation and negative impacts on wildlife. Considering the limited benefits and significant problems created by trophy hunting and mass tourism, we suggest trophy hunting should be stopped and mass tourism Animals 2020, 10, 597 2 of 20 should be shifted to ecotourism in and around KNP. Ecotourism could mitigate human-Snow leopard conflicts and help conserve the fragile ecosystem, while generating enough revenue incentives for the community to protect biodiversity and compensate for livestock depredation losses to Snow leopards. Our results may have implications for management of trophy hunting and mass tourism in other similar regions that deserve further investigation.
Article
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Trophy hunting and mass tourism are the two major interventions designed to provide various socioeconomic and ecological benefits at the local and regional levels. However, these interventions have raised some serious concerns that need to be addressed. This study was conducted in Khunjerab National Park (KNP) with an aim to analyze comparatively the socioeconomic and ecological impacts of trophy hunting and mass tourism over the last three decades within the context of sustainability. Focus Group Discussions (FGDs) with key stakeholders and household interviews were conducted to collect data on trophy hunting and mass tourism, and on local attitudes towards these two interventions in and around KNP. The results revealed that 170 Ibex (Capra sibirica) and 12 Blue sheep (Pseudois nayaur) were hunted in the study area over the past three decades, and trophy hunting was not based on a sustainable harvest level. Trophy hunting on average generated USD 16,272 annual revenue, which was invested in community development. However, trophy hunting has greatly changed the attitudes of local residents towards wildlife: a positive attitude towards the wild ungulates and strongly negative attitude towards wild carnivores. In addition, trophy hunting has reduced the availability of ungulate prey species for Snow leopards (Panthera uncia), and consequently, Snow leopards have increased their predation on domestic livestock. This has, in turn, increased human–snow leopard conflict, as negative attitudes towards carnivores result in retaliatory killing of Snow leopards. Furthermore, according to official record data, the number of tourists to KNP has increased tremendously by 10,437.8%, from 1382 in 1999 to 145,633 in 2018. Mass tourism on average generated USD 33,904 annually and provided opportunities for locals to earn high incomes, but it caused damages to the environment and ecosystem in KNP through pollution generation and negative impacts on wildlife. Considering the limited benefits and significant problems created by trophy hunting and mass tourism, we suggest trophy hunting should be stopped and mass tourism should be shifted to ecotourism in and around KNP. Ecotourism could mitigate human–Snow leopard conflicts and help conserve the fragile ecosystem, while generating enough revenue incentives for the community to protect biodiversity and compensate for livestock depredation losses to Snow leopards. Our results may have implications for management of trophy hunting and mass tourism in other similar regions that deserve further investigation.
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The Namibian authorities endeavour to implement a rangeland resources management policy at national level. The first line of action is the allocation of livestock marketing priorities to the most drought‐affected areas. Another potential application is the estimation of land value in terms of grazing capacity, as a base for land purchase and redistribution for private land taxation. Accurate and up‐to‐date information on the resources, which are very variable in time and space, is indispensable for rational and efficient decision‐making. In this regard, low‐resolution satellite imagery appears to be a practical and suitable source of data for non‐biased and reasonably accurate estimation of forage production over the whole country. Using 17 years of AVHRR and VEGETATION satellite data over Namibia, seasonal biomass production estimates were obtained with a simple but operational vegetation production model known as the Monteith model. The accuracy of the products was assessed by comparison to field measurements carried out between 1999 and 2001, showing good correspondence and a residual error of approximately 25% of the average. Long‐term averages of biomass production from all available satellite data (17 growing seasons) give an indication of the “normal” potential of the land in terms of grazing. This can be used for marketing priority allocations, the comparison of the production of the current season to the long‐term average allowing to identify the most problematic zones and to quantify the severity of a crisis. The long‐term average is also a good base for land value assessment, although complementary processing is required. The products are integrated in a GIS environment to be used with complementary geographic information. The potential of such a system for decision making within the Namibian range resources management policy is discussed.
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A database of approximately 9000 trophy measurements of ungulates hunted in South Africa between 1993 and 2001 was analysed in order to detect species-specific, regional variation in mean trophy quality. Blesbok (Damaliscus dorcas), eland (Taurotragus oryx), impala (Aepyceros melampus), kudu (Tragelaphus strepsiceros), mountain reedbuck (Redunca fulvorufula) and springbok (Antidorcas marsupialis) showed statistically significant variation in trophy quality. A number of other species including blue wildebeest (Connochaetus taurinus), black wildebeest (Connochaetus gnou), bushbuck (Tragelaphus angusticeps), common reedbuck (Redunca redunca), gemsbok (Oryx grazella), red hartebeest (Alcelaphus buselaphus), nyala (Tragelaphus angasit) and waterbuck (Kobus ellipsiprymnus) were insignificant. The manipulation of trophy quality on ranches is speculated to be the major cause of these significant regional variations. It is recommended that species-specific baselines of trophy quality and associated levels of acceptable manipulation be established and incorporated into a national trophy quality monitoring programme to provide some level of protection to an industry that contributes significantly to the South African economy.
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At a landscape scale, the combined influence of biotic and abiotic factors may determine the distribution patterns of large herbivores in African savanna ecosystems. Herbivores foraging in these ecosystems may become nutritionally stressed during an annual dry season when both forage quality and quantity are reduced. Additionally, the locations of water sources may impose a landscape-scale constraint on dry-season herbivore distributions. We used logistic regression to analyze 13 years of aerial census data collected in the Kruger National Park (KNP), South Africa, and evaluated hypotheses regarding the relative influences that surface water, forage quality, and forage quantity exert on the dry-season, landscape-scale distribution patterns of eight herbivore species, Hypotheses regarding the degree of correlation between species' distributions and distance to water were developed using previous observations of species' relative water dependence. We also developed hypotheses regarding species' responses to the trade-off that may occur between surface-water constraints and nutritional requirements when either forage quality or quantity is reduced. In general, we expect an increase in species' mean distance to water as a result of individuals mitigating limitations in nutritional requirements (i.e., intake quality or quantity) by foraging farther from water. Our analyses, suggest that the trade-off between nutritional requirements and surface-water constraints that species ace varies according to the species' water dependence, size, and gut morphology. Of the four grazers considered in our analyses, waterbuck. distributions appear to be constrained primarily by surface-water availability. Distributions of buffalo, a large ruminant grazer, suggest that individuals face a trade-off between nutritional requirements and surface-water constraints when forage quantity is reduced.. Alternatively, distributions of wildebeest, a-smaller ruminant grazer, suggest that individuals face this' trade-off when access-to high-quality forage is limited. In comparison to buffalo and, wildebeest, the strength of this trade-off is moderate for zebra, a nonruminant similar in size to wildebeest, when either forage quality or quantity is reduced. Distribution patterns for browsers are characterized by a weak relationship with distance to Water, as expected for these relatively water-independent species. Population densities relative to forage quality confound exploration of this trade-off for mixed feeders.
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Factors affecting horn size in wild Caprinae are of biological and socio-economic interest because several species are selectively harvested on the basis of this heritable character. We analysed temporal trends in horn size in two mountain ungulates from south-eastern Spain, the Iberian wild goat Capra pyrenaica and the aoudad Ammotragus lervia. Trophy harvest is the main way in which these two species are exploited, although ‘poor-quality’ aoudads are also selectively removed. In recent years, both populations have suffered drastic decreases in number due to outbreaks of sarcoptic mange that led to the suspension of hunting for several years. Horn length in harvested male wild goats and aoudads declined during our study period. Over an 18-year period, the mean age of male goats shot as trophies rose by four years, while the age of trophy-harvested aoudads decreased by around six months over a 9-year period. Age and environmental conditions during the first few years of life explained 20% of variance in horn size in Iberian wild goat and 53% in aoudad. Population density early in life explained much of the reduction in goat horn size over time. Nevertheless, the major fall in population densities after the sarcoptic mange outbreaks did not lead to a recovery in horn size in either species. We suggest that the selective removal of large-horned animals may contribute to a decline in horn size. Other factors that may also explain the observed pattern include changes in interspecific competition, long-lasting maternal effects and reduced carrying capacity due to overgrazing during high density periods. Unfortunately, our data sets did not allow us to account for the possible effects of these factors.
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Moose Alces alces gigas in Alaska, USA, exhibit extreme sexual dimorphism, with adult males possessing large, elaborate antlers. Antler size and conformation are influenced by age, nutrition and genetics, and these bony structures serve to establish social rank and affect mating success. Population density, combined with anthropogenic effects such as harvest, is thought to influence antler size. Antler size increased as densities of moose decreased, ostensibly a density-dependent response related to enhanced nutrition at low densities. The vegetation type where moose were harvested also affected antler size, with the largest-antlered males occupying more open habitats. Hunts with guides occurred in areas with low moose density, minimized hunter interference and increased rates of success. Such hunts harvested moose with larger antler spreads than did non-guided hunts. Knowledge and abilities allowed guides to satisfy demands of trophy hunters, who are an integral part of the Alaskan economy. Heavy harvest by humans was also associated with decreased antler size of moose, probably via a downward shift in the age structure of the population resulting in younger males with smaller antlers. Nevertheless, density-dependence was more influential than effects of harvest on age structure in determining antler size of male moose. Indeed, antlers are likely under strong sexual selection, but we demonstrate that resource availability influenced the distribution of these sexually selected characters across the landscape. We argue that understanding population density in relation to carrying capacity (K) and the age structure of males is necessary to interpret potential consequences of harvest on the genetics of moose and other large herbivores. Our results provide researchers and managers with a better understanding of variables that affect the physical condition, antler size, and perhaps the genetic composition of populations, which may be useful in managing and modelling moose populations.
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Hunting management of red deer Cervus elaphus populations may tend to increase population densities to maximise annual yield. Some studies have shown that density and low winter temperatures affect red deer populations in central and northern Europe, but these results cannot be extrapolated to red deer populations in the Mediterranean region where the limiting season is summer instead of winter. The two regions are predicted to experience different climate change effects: while rainfall may increase in northern latitudes, heavier droughts are expected in the Mediterranean region. We studied red deer populations of different densities on 19 hunting estates in southern Spain during two years with contrasting precipitation levels. Our aim was to quantify the combined effects of drought and population density on the development of stags, which is the main economic objective of hunting management in these areas. We found that drought affected body and antler size negatively, and that the effects were more severe in populations of high density. On the basis of our results, we recommend reducing the current densities of red deer in southern Spain to maintain the economic and environmental sustainability of hunting exploitation in the context of global climate change.
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A database of approximately 9000 trophy measurements of ungulates hunted in South Africa between 1993 and 2001 was analysed in order to detect monotonic trends in trophy quality over time. In a species-specific analysis, declines were found for impala (Aepyceros melampus), springbok (Antidorcas marsupialis) and mountain reedbuck (Redunca fulvorufula). In an area-specific analysis, a decline was found in the Northern Cape Province. Conversely, blesbok (Damaliscus dorcas phillipsi) (species-specific) and the Free State Province (area-specific) showed increases in trophy quality. As an economic indicator, the monitoring of trophy quality allows agencies to potentially evaluate the quality and sustainability of their 'huntable' ungulate resources.
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This book is available for purchase, The 1993 version is available on the page at http://distancesampling.org/whatisds.html
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Adult male impala defended breeding territories during the short rut in southern Africa. Serious injury from fighting was uncommon, but energetic and growth constraints may have limited dominance. Matings were probably synchronised with the lunar cycle. A few ♂♂ achieved a high mating success by tending several ♀♀, simultaneously in oestrus. A regional comparison suggests that lifetime breeding differential among ♂♂ is greater where breeding seasons are short.ZusammenfassungVorherrschaft, Paarungserfolg und Brunstkosten des Impalabockes wurden im Sengwa Wildlife Research Gebiet in Zimbabwe erforscht. — Die Brunst lag zeitlich so, daß säugende ♀♀ eine maximale Futterqualität erhielten. Der zeitliche Brunstschwerpunkt in 6 Jahren schwankte über ein Intervall von 20 Tagen, abhängig vom Mondzyklus.Die meisten Paarungen erfolgten innerhalb von 2–3 Wochen, und in einer Gruppe von 67 erwachsenen ♀♀ paarten sich 90% innerhalb von 10 Tagen. Nur ♂♂ im Alter von 4,5 bis 8,5 Jahren kämpften in dieser Zeit erfolgreich um Paarungsgründe. Einige hatten großen Paarungserfolg, indem sie mehrere ♀♀ besprangen, die gleichzeitig brünstig waren.Schwerwiegende Verletzungen durch Kämpfe waren selten, doch sanken die Fettreserven der erwachsenen ♂♂ während der Brunstzeit infolge verkürzter Nahrungsaufnahme. Nicht Verletzungsrisiko, sondern Energie- und Wachs-tumsgrenzen beschränken die Kampfkraft des Impala- ♂, so daß es nicht mehr fähig ist, eine ganze Herde zu verteidigen.Ein regionaler Vergleich des Paarungs-Systems der Impala legt nahe, daß kurze Paarungszeiten verbunden sind mit größeren Unterschieden im Paarungserfolg der ♂♂. Der Grund dafür ist wohl das Energiedefizit während der Dauer der Territorialität, wenn Fortpflanzung asaisonal ist.
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IntroductionStudy areaConservation hunting programmeFutureConclusions AcknowledgementsReferences
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Horns of bovids are important social organs, their growth is often indicative of population characteristics and habitat quality, but Little is known of the factors affecting their growth in individuals. We studied horn growth of 135 (51 males, 84 females) marked mountain goats (Oreamnos americanus) in Alberta, Canada, for 9 years. In both sexes, horn growth was quadratic during the first 5 years of life and not significant after 5 years of age. Goats completed 93% of horn growth by 3 years of age. Horns of males grew more than those of females during the first 1.5 years of life. Horns of females grew more than those of males during the third year. Although males maintained longer horns than females because of their longer first increment, adult males had shorter horns than females for a given body size. Males had thicker horns than females at all ages, absolutely or relative to body size. Horn growth early in life was correlated negatively with later growth. Annual growth increments of horns of females
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