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Estimated volume of soil displaced from porcupine diggings and surface area disturbed per habitat type on Glenlyon Farm, Nieuwoudtville
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Cape porcupines (Hystrix africaeaustralis) appear to have an important influence on landscapes through both biotic (foraging) and abiotic (soil turnover) impacts. Porcupine abundance and abiotic effects across the landscape were investigated in Nieuwoudtville, South Africa, a semi-arid area characterized by an extraordinary diversity and abundance...
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Context 1
... estimated that porcupines annually displaced a total of 1.6 m 3 of soil ha À1 (Table 4). The greatest disturbance took place in the Dolerite Plains (2.2 m 3 ha À1 yr À1 ) and Dolerite Ridges (2.1 m 3 ha À1 yr À1 ) ( Table 4). ...Context 2
... estimated that porcupines annually displaced a total of 1.6 m 3 of soil ha À1 (Table 4). The greatest disturbance took place in the Dolerite Plains (2.2 m 3 ha À1 yr À1 ) and Dolerite Ridges (2.1 m 3 ha À1 yr À1 ) ( Table 4). The Old Lands had very few diggings but the volumes of the individual diggings on these lands Table 3 Mean digging volume, projected life-span, digging density and digging numbers day À1 ha À1 (DHD) for four different habitat types on Glenlyon farm, Nieuwoudtville were larger than those in other habitat types, so that total soil turnover was remarkably high. ...Context 3
... Old Lands had very few diggings but the volumes of the individual diggings on these lands Table 3 Mean digging volume, projected life-span, digging density and digging numbers day À1 ha À1 (DHD) for four different habitat types on Glenlyon farm, Nieuwoudtville were larger than those in other habitat types, so that total soil turnover was remarkably high. We estimated that 0.34% of the total surface area of the study site is disturbed per year by porcupines (Table 4). Of all the habitats, Dolerite Ridges has the most disturbance (5273 m 2 ha À1 yr À1 ) (Table 4), even though this estimate did not include the accumulated densities of churned over soil (27.6792.1 m 2 (mean71 SD) per hectare, n ¼ 30). ...Context 4
... estimated that 0.34% of the total surface area of the study site is disturbed per year by porcupines (Table 4). Of all the habitats, Dolerite Ridges has the most disturbance (5273 m 2 ha À1 yr À1 ) (Table 4), even though this estimate did not include the accumulated densities of churned over soil (27.6792.1 m 2 (mean71 SD) per hectare, n ¼ 30). ...Citations
... While these size ranges are useful as a general guide for determining which species created or most recently modified a burrow, it is important to point out that burrow dimensions may differ by substrate and location (Whittington-Jones 2006) and are ever-changing due to continual modification or disturbance by a variety of animals and plants, as well as the impacts of wind and water which lead to erosion, in-fill and eventual collapse (Bragg et al. 2005). ...
The black-footed cat (Felis nigripes) is the smallest and one of the rarest cats in Africa. Endemic to the semi-arid regions of South Africa, Namibia and Botswana, this nocturnal carnivore spends daytime in burrows, thus avoiding high temperatures and diurnal predators. Despite the importance of burrows, den usage has never been studied in detail for this species. Here we report on the frequency with which female black-footed cats use burrows of different dimensions and compared with burrow availability. The entrances of 50 dens, used by five radio-collared black-footed cats over four weeks, were scanned with LiDAR to measure tunnel width (mean = 15.2 ± 3.9 cm) and height (mean = 13.9 ± 3.6 cm). Of these, 98% (n = 49) most closely matched the dimensions of springhare (Pedetes capensis) burrows. Each cat used a mean of 11.6 den sites and spent a mean of 2.0 consecutive days in a den before selecting a new one. When kittens reached an age of 44-50 days, mothers switched from using a den for a mean of six days-per-den, to changing dens every day. Our results suggest that female black-footed cats are reliant upon springhares to provide suitable daytime refugia and maternity dens in southern Namibia. Further studies should be conducted to determine what den sites are selected in the absence of springhare, and whether localised persecution of springhare impacts the survival of black-footed cats.
... The species is intensively poached in the Northwestern part of its range for meat consumption, traditional medicine, and sorcery practices (Aulagnier et al. 2017). Moreover, and besides its important influence on landscape through both biotic (plant dispersal) and abiotic (water percolation and soil turnover) impacts (Gutterman, 1982, Lovegrove & Jarvis 1986, Dean & Milton 1991, Bragg et al. 2005, it is broadly considered a pest for agriculture due to its intense digging activity. The European Habitat Directive mandates the protection of the crested porcupine (Clavero 2014) as well as the compensation for crop damages in agricultural fields (e.g. ...
We investigated the feeding ecology of the crested porcupine Hystrix cristata in a semi-arid area of its northwestern Algerian native range over 8 months (September to April). Our results from micro-histological analysis based on faecal pellets revealed that this strict herbivore ate only 10 plant species, 8 wild and 2 cultivated, belonging to 9 families including Lamiaceae, Palmaceae, Poaceae, Ramnaceae and Fabaceae. The autumn diet was dominated by Thymus algeriensis, Ziziphus lotus, Chamaerops humilis and Triticum aestivum, the winter diet by T. algeriensis and C. humilis, and the spring diet by Muscari comosum, with a large amount of Vicia faba and T. aestivum. We confirm the role of this rodent species as a generalist herbivore which barely feeds on cultivated plants when wild resources are diverse and abundant.
... This creation of a suitable microclimate is especially important in dryland systems, where burrows can buffer against thermal extremes (Kinlaw, 1999;Whitford & Kay, 1999). In addition to temperature modification, burrows also potentially attract other species by acting as seed (Hawkins & Nicoletto, 1992;Bragg, Donaldson & Ryan, 2005) and moisture traps (Gutterman, 2003;Louw, Haussmann & le Roux, 2021). ...
... This may indicate that the roots of the trees were abandoned as a food source in the wet season. Bragg et al. (2005) reported that geophytes were likely a primary food source in the diet of porcupines in the wet season in the Northern Cape of South Africa. Seasonality may thus trigger the switch in diet of Cape porcupines. ...
In terrestrial ecosystems, the activities of semi‐fossorial animals such as Cape porcupines have important landscape effects that may manifest in the dry season when the availability of above‐ground forage becomes limiting. We investigated the effects of foraging activities of Cape porcupines on savanna landscapes. We measured the size (surface area and depth) of foraging holes of porcupines located at the base of trees in the dry season in two mesic savanna sites at Roodeplaat Farm and Bisley Valley Nature Reserve in South Africa. We also recorded plant and animal activities inside the foraging holes for 3 months. The depth of foraging holes beneath small trees ( Vachellia nilotica ) was greater than depths beneath old trees ( V. robusta and D. rotundifolia ). This resulted in the subsequent death of most (>50%) small impacted trees in the dry season at Bisley. The surface area of foraging holes for older trees was greater than that for small trees and even greater for old holes. This study showed that porcupines kill trees or expose them to secondary attacks. The physical impacts of semi‐fossorial herbivores in savannas can be significant, with contributions to direct and indirect landscape transformation and restoration.
... The porcupine density is also higher in the northern part of the park (9.7 individuals/1000 ha) compared to the southern part (1.0 individuals/1000 ha). For many porcupine populations, higher densities are reported, reaching 40 and even 80 individuals/1000 ha (Sever and Mendelssohn, 1991;Bragga et al., 2005). The low porcupine densities in Hyrcan Park can be explained by the fact that the animals live here in the marginal part of their range, where, as a rule, living conditions are worse (Lawton, 1993;Lomolino and Channell, 1995). ...
Based on the random encounter model, the population densities of species that are potentially prey or competitor to the leopard (Panthera pardus) were estimated in Hyrcan National Park, Azerbaijan. Data obtained from 18 camera traps were processed, 11 of which were installed in the southern part of the park, and seven of which are in the northern part. The total operating time of the cameras amounted to 3950 traps per day for the period from
... For example, Dentzien-Dias and Figueiredo (2015) found that tuco-tuco (Ctenomps sp) prefer to inhabit sandy soils in South America, while Bobak marmot (Rodentia sciuridae) of Eastern Europe and Central Asia prefer mostly arable cropland, dark kastanozems, as well as southern chernozem soil types and grassland environments. Cape porcupines in South Africa, in turn, burrow where geophytes (their food source) occur and they prefer to burrow in mesic environments (Bragg, Donaldson & Ryan, 2005). Davis and Kalisz (1992) The biotic and abiotic components of the terrestrial environment also seem to play a role in the distribution of burrows of the aardvark (Orycteropus afer), a medium-sized (approximately 50-80 kg) burrowing mammal species restricted to sub-Saharan Africa (Melton, 1976). ...
... As old burrows fill up, new burrows are created in new locations. Porcupine diggings in the Northern Cape, for example, have a lifespan of between approximately one and three years (Bragg, Donaldson & Ryan, 2005). Similarly, in our study, the 250 aardvark burrows recorded in 2015 had deteriorated to such an extent, that they could not be located again in 2020. ...
This paper contributes towards rural planning policy and management through a critical analysis of the environmental education programmes in Biriiri Ward 17, Chimanimani District, Zimbabwe. Focus is on its planning, implementation, and programme review structures in place. Key informants were drawn from educators and field monitors employed by Towards Sustainable Use of Resources Organisation (TSURO), Agricultural, Technical and Extension Services (AGRITEX) department, Environmental Management Agency (EMA), Chimanimani Rural District Council (CRDC) and Christian Care. Chief Muusha, headman Saurombe, village heads and villager-composed focus group discussions (FDGs) also provided essential data for the research. Findings indicated that villagers receive education in the area through various Learning Support Materials (LSMs), a situation that has commendably augmented livelihood sustainability in the area. However, lack of adequate grassroots community participation, fragmented policy structures and limited financial capital for more capacity development and project funding hinder beneficiaries from deriving maximum benefit from sustainability education initiatives. The paper recommends heightened capacity building supported by effective participation of grassroots communities and traditional leaders to achieve environmental sustainability goals.
... In South Africa, a number of burrowing mammal species, such as warthog (Phacochoerus africanus, Swanepoel et al. 2016), aardvark (Orcyteropus after, Whittington-Jones et al. 2011) and porcupine (Hystrix africaeaustralis, Bragg et al. 2005), are ubiquitous on farms. From an agricultural perspective, a number of reasons exist for farmers to potentially view burrowing mammals in an unfavourable light. ...
Burrowing mammals are ubiquitous on farms in South Africa and can hinder agricultural practices. This study explored farmer perspectives of these species, and specifically the factors that influence these perspectives. Forty-four farmers responded to a questionnaire that assessed their ecological knowledge of, tolerance towards and lethal management of burrowing mammals that occur on their farms. The results from generalised linear models showed that neither farmer age, nor level of education are accurate predictors of ecological knowledge, overall tolerance towards burrowers, or their lethal management. Knowledge of burrowing mammals showed a significant relationship with tolerance, with more knowledgeable individuals displaying higher levels of tolerance. However, a farmer’s overall tolerance towards burrowing species did not affect the number of species managed. Our results also suggest that different values are attached to different species when it comes to lethal management. Thus, farmers commonly controlled the numbers of the problem rodent species, Highveld gerbil (Gerbilliscus brantsii) and Cape ground squirrel (Xerus inauris), but were less likely to manage black-backed jackal (Canis mesomelas) and warthog (Phacochoerus africanus), even when experiencing these as problematic. We suggest that the larger, more charismatic species possibly evoke more sympathy from farmers. Agro-ecosystems are likely to become increasingly important for conservation in the future, and we encourage continued studies on the environmental attitudes and approaches of agricultural practitioners as a means to understanding the current status and future trends in ecologically sustainable agriculture.
... Cape porcupines are generalist herbivores that occur throughout southern Africa (van Aarde 1987) and they feed on natural vegetation and cultivated plants (Bragg et al. 2005;Hafeez et al. 2011). Their diet is mainly made up of tubers, corms, roots, and tree bark, and the foraging activities of porcupines may lead to death of the plants that are impacted (Bruno and Riccardi 1995;Mohamed 2011). ...
... Bark damage by porcupines is characteristic of the animal, and is widely identifiable by landowners (e.g., at Goss), wildlife rangers (at Bisley) and the authors. The literature (e.g., Yeaton 1988; de Villiers and van Aarde 1994; Bragg et al. 2005) provides additional descriptions that link the porcupine to the observed bark damage. In addition, no other large mammalian species that is known to feed substantially on tree bark from ground level to 0.5 m occur at the three sites. ...
... For example, Yeaton (1988) found that porcupines showed a preference for Burkea africana trees over Vachellia spp. in the Nylsvley Nature Reserve in Limpopo Province of South Africa. In the Bokkeveld Plateau in the Northern Cape Province of South Africa, porcupines consumed the more abundant geophytes of the over hundred species available (Bragg et al. 2005). Like Vachellia species, there has been documented Table 1. ...
Herbivory plays a fundamental role in determining the structure of savannas. The impacts of small and medium-sized mammalian herbivores on trees in savannas remain poorly understood because most research attention focuses on large herbivores such as elephants whose destructive effects on trees can be pervasive at landscape scales. On the other hand, feeding activities of generalist herbivores such as Cape porcupines on woody plants can lead to tree mortality. This study investigated the utilisation of woody plants by the Cape porcupine in three mesic savanna sites in South Africa. We determined the woody plant diet of the porcupine for the early and late dry seasons at Roodeplaat Farm in Gauteng Province, and at Goss Game Farm and Bisley Valley Nature Reserve in KwaZulu-Natal Province. Thirty and twenty randomly located quadrats (30 m × 30 m) were laid at Roodeplaat and Goss, respectively, while 10 smaller quadrats (10 m × 10 m) were laid at Bisley. We measured stem diameter and the length and width of bark scars made by porcupines on stems of woody plants. We collected ten dung samples from each study site in the wet and dry seasons for quantification of woody material in porcupine diet. Porcupine foraging behaviour impacted different tree species at each site: Vachellia robusta at Roodeplaat, Spirostachys africana at Goss and Vachellia nilotica at Bisley. Each of these trees was dominant at each site. More scarring and tree mortality were recorded at Bisley with almost 70% tree sapling mortality occurring on trees that porcupine fed on. The size of bark scars was greater at Goss (P < 0.01) than at Roodeplaat and Bisley, which were similar. The area of bark damage on S. africana trees differed significantly by stem diameter size class (P = 0.007) and was greater for small stems (size class < 7.1 cm) than the larger stems (size classes 7.1-14 cm and 14.1-21). For all the study sites, dung samples revealed that woody material contributed over 80% of the porcupine diet during the dry season, but was lower at 35% during the wet season for Roodeplaat, although it was consistently high for Bisley at 79%. Porcupine foraging activities substantially contributed to tree mortality at each site. We posit that porcupine induced mortality on dominant tree species at each site may contribute to structural heterogeneity in woody plant vegetation in mesic savannas.
... Water, shelter, and food are the three critical elements required for the survival of animals in all environments (Krebs, 1985). Burrowing activity is an important form of natural disturbance in many types of ecosystems, and existing evidence suggests that the burrows of ecosystem engineers have profound effects on shaping the abiotic environment, leading to increased integrity of the biotic community (Bragg et al., 2005;Desbiez & Kluyber, 2013). Engineering effects on species abundance and richness indirectly produce changes in the abundance of one species by a second species that directly alters the abundance of the third species, whereas indirect interactions affect the abundance of one species through a second species, including changes in the behavioral or physiological trait of a third species (Abrams, 1982;Křivan & Schmitz, 2004). ...
... Finally, mound and soil pits (which are created next to each mound by marmots digging) are believed to affect plant diversity by acting as a catchment for seeds (Spencer et al., 1985;Dean & Milton, 1991;Alkon, 1999;Whitford & Kay, 1999;Bragg et al., 2005) and providing available space and resources for less competitive, colonizing species to establish themselves (Schall & Leverich, 1982;Hobbs & Hobbs, 1987;Goldberg & Gross, 1988;Reader & Buck, 1991;Davis et al., 1995). Thus, the concentration of resources and favorable microhabitat of burrows create a range of niches that a variety of species can exploit (Hansell, 1993). ...
... However, the NH4-N flux is more complex than the PO4-P flux because NH4 participates directly and/or indirectly in a greater number of aerobic and anaerobic microbial transformations involved in sediment N cycling, such as ammonification and nitrification, than does PO4 in sediment P cycling (Fenchell et al., 1998). In the American prairie, areas on and around burrow systems tend to have a greater presence of symbiotic fungi than surrounding habitat (Whitford & Kay, 1999;Reichman & Smith, 1990) Burrows provide resources -Burrows can also act as traps for windblown seeds, thereby concentrating food resources for granivorous and omnivorous animals such as rodents (Dean & Milton, 1991;Price & Joyner, 1997;Alkon, 1999;Whitford & Kay, 1999;Bragg et al., 2005). Many rodent species exhibit food-storing behavior and build simple lateral extensions of burrows that function as cache sites. ...
... One good example of a behavioral adaptation is living in burrows, which offers a buffered microclimate, predation avoidance, and, in some cases, access to food resources (Schmidt-Nielson and Schmidt-Nielson 1950;Reichman and Smith 1990;Kinlaw 1999;Whitford and Kay 1999;Williams et al. 1999). Burrow mounds can also act as traps for windblown seeds, thereby concentrating food for granivorous and omnivorous animals, such as many rodents (Dean and Milton 1991;Alkon 1999;Whitford and Kay 1999;Bragg et al. 2005). Thus, the concentration of resources and the favorable microhabitat of burrows create a range of niches that a variety of species can exploit (Hansell 1993). ...
Mongolian marmots (Marmota sibirica) live in colonies that consist of numerous burrows and are considered ecosystem engineers. Although once a common steppe species, marmots are now endangered due to overharvesting, which has led to concerns over the impacts of their loss on other species. The decline of marmots likely affected other species given their importance to the ecosystems they inhabit. To examine the role of marmots on small mammal, we established Sherman traps and drift fence arrays with associated pitfall and funnel traps on active marmot colonies, inactive colonies, and control sites in the forest-steppe and semi-desert zones of Mongolia. Overall, we identified 385 individuals representing 11 species of rodents and 1 species of bat in Ikh Nart and 149 individuals representing 2 species of rodents and 1 species of insectivore from Hustai. We found mixed results between diversity indices and abundance of small mammals on treatment and control sites, complicating the picture. During periods of greater precipitation and resulting higher vegetation cover, species abundance and the Shannon-Wiener, Simpson's, and evenness indices all changed significantly, suggesting that the effect of marmots on other species varies based on environmental conditions.
