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The effects of increasing human activity on brown bear use of an Alaskan river
Abstract
We assessed the effects of increasing human activity on brown bear Ursus arctos use of a salmon spawning stream by comparing observations (865 h) collected 1988–1990 to those (293 h) from 1992 when human activities extended a week later into the fall feeding period (26 August–12 October). We classified individual adult bears according to their tolerance of people as ‘habituated’, or ‘non-habituated’; sub-adults were considered a third behavioural class. In 1992, non-habituated adults (n = 14 of 22 total adults) reduced their activity in apparent response to an extended lodge season, by delaying their use of the river by 17 days. In contrast, habituated adult bear activity remained similar among years, and sub-adult activity increased > four-fold in 1992. We suggest that the human-induced decrease in non-habituated adult activity may have allowed the increased levels of sub-adult activity.
... Habituation changes the type of interactions that humans have with bears, and is positive or negative depending on the circumstances. Habitat displacement and behavioral adjustments can lead to decreased individual foraging efficiency (Olson et al. 1997) or reduced access to high quality habitats. ...
... Grizzly bears have been found to exhibit a high level of individual variation (Himmer 1996; White et al. 1999;MacHutchon 2001); we, therefore, assumed that identifying individual bears would increase the reliability of results. The observation of prominent markings and scarring was used to distinguish individuals (Olson et al. 1997;DeBruyn et al. 2004;Nevin and Gilbert 2005b). We recorded (using a Canon digital video camera with a 100x zoom lens) and photographed (using a Canon AE1 SLR camera with a 300 mm zoom lens and a Canon Powershot A80 digital camera) each bear. ...
... Bear activity budgets were calculated for "non-viewing" and "viewing" periods within each sample through the summation of time spent in each behavior, and division of that sum into the total length of time for the sample (Olson et al. 1997;White et al. 1999;MacHutchon 2001). Only activity budgets for bears with more than three samples were used in statistical analyses; data from all other bears were excluded. ...
All forms of recreation and tourism, including wildlife viewing, have the potential to alter wildlife habitat, behavior, survival, and/or reproductive success. The increasing number of visitors pursuing bear-viewing activities in coastal British Columbia, Canada, and Alaska, United States, has led to a number of studies assessing the impact of wildlife viewing on bear behavior. This study, the first to assess the impact of boat-based bear viewing in this region, used focal sampling to measure bear activity budgets in the absence and presence of nonresearch bear-viewing vessels. We found that: (1) some grizzly bears were clearly tolerant of wildlife viewing activities while others were not; (2) individual variation of bears' response to tourists was significant, introducing considerable uncertainty in attempting to assess medium- to long-term impacts of wildlife viewing; (3) males were rarely observed outside of the mating season, suggesting females (especially those with cubs) may use viewing areas as refuges from male grizzly bears; and (4) overt reaction distances varied greatly, suggesting that one appropriate management option may be to ensure boat captains can recognize potential displacement behavior in bears to avoid affecting subject animals. Some of the uncertainty arising from the biological research could be tempered by examining the social perspective of bear viewing tours to create an appropriate management plan for the K'tzim-a-deen Inlet Conservancy.
... Additionally, salmon-bear interactions can be limited by human activities. For example, studies in Alaska, USA, suggested that humans strongly influence the daily and seasonal activities of brown bears along salmon-spawning streams (Olson et al. 1997(Olson et al. , 1998, and bears avoid using salmon streams where people are frequently found (Olson and Gilbert 1994). ...
... Additionally, salmon-bear interactions can be limited by human activities. For example, studies in Alaska, USA, suggested that humans strongly influence the daily and seasonal activities of brown bears along salmon-spawning streams (Olson et al. 1997(Olson et al. , 1998, and bears avoid using salmon streams where people are frequently found (Olson and Gilbert 1994). ...
... Additionally, salmon-bear interactions can be limited by human activities. For example, studies in Alaska, USA, suggested that humans strongly influence the daily and seasonal activities of brown bears along salmon-spawning streams (Olson et al. 1997(Olson et al. , 1998, and bears avoid using salmon streams where people are frequently found (Olson and Gilbert 1994). ...
Interactions between brown bears (Ursus arctos) and anadromous salmon (Oncorhynchus spp.) constitute a unique energy pathway that facilitates nutrient cycling between marine and terrestrial ecosystems. Previous studies have documented variation in salmon consumption by brown bears; however, few have addressed potential anthropogenic factors influencing consumption. We assessed diet of brown bears on Hokkaido Island, Japan, using carbon and nitrogen stable isotopes to determine the effect of demographic (age and sex) and environmental (developed and undeveloped area) factors on salmon consumption. We collected thigh bones from 190 harvested bears from 1996 to 2011 and samples of their major dietary foods from 2009 to 2011, and we then estimated the potential contributions of these foods to the diets of brown bears using a Bayesian mixing model. Brown bears consumed more herbs, fruits, and corn than terrestrial animals or salmon at the population level. However, the dietary contribution of salmon varied widely among bears; in some cases, it comprised >30% of the total diet. Salmon consumption also varied by bear age class, sex, and location. Low salmon consumption by adult females with cubs suggested avoidance of salmon-spawning areas to minimize risk to their cubs. Bears inhabiting undeveloped areas were more likely to consume salmon than those inhabiting developed areas, suggesting that human activities restrict brown bears' salmon consumption. The lower salmon intake of Hokkaido brown bears compared with Alaskan brown bears may be attributed in part to extensive human development on Hokkaido Island, including in-stream structures that preclude salmon migrations and agricultural crops that provide an alternative food subsidy.
... Blanchard and Knight (1991) reported that only adult males occupied the highest-quality habitat in years with poorer food availability, and that subadult males and females with dependent offspring avoided both lone females and adult males by choosing more secure over more productive habitats. Temporal segregation is also common at food aggregation sites, where adult male brown bears occur more often, and displace females with dependent offspring and subadults (Storonov & Stokes 1972, Craighead et al. 1995, Olson et al. 1997, Nevin & Gilbert 2005a, b, Peirce & Van Daele 2006, Rode et al. 2006b). Subadults and females with cubs may be risk-averse because they exploit salmon streams less when large males are present and when foraging efficiency is high (i.e. at night; Klinka & Reimchen 2002). ...
... Several researchers suggest that adult males decrease their activity with increasing human activity, whereas increased human activity creates refuge and feeding opportunities for subadults and females with cubs at brown bear viewing sites at salmon rivers (Smith 2002, Nevin & Gilbert 2005a, b, Rode et al. 2006b) and meadows (Gunther 1990). More female brown bears than males, and more subadults than adults, occur with increasing numbers of humans at salmon streams (Warner 1987, Olson et al. 1997. Male polar bears Ursus maritimus also show increased vigilance towards viewing tourists, whereas females respond in the opposite manner, by increasing vigilance when people are not present (Dyck & Baydack 2004). ...
... Black bears may reduce the levels of competition with and predation by brown bears they experience, by using areas near humans (MacHutchon et al. 1998, Schwartz et al. 2010. Settlements or areas in which humans are active have been suggested to form refuges for some brown bears against conspecifics (Mattson et al. 1987, Mattson 1990, Albert & Bowyer 1991, Wielgus & Bunnell 1994, Olson et al. 1997, Mueller et al. 2004, Nevin & Gilbert 2005a, Rode et al. 2006a, b, Schwartz et al. 2010. ...
Large carnivores ( LC s), such as bears ( U rsidae), are commonly believed to occur near human settlements because they have a learned tolerance of humans (human habituation) and because they associate humans with accessible high‐quality foods (food conditioning). Young bears and females with cubs are often overrepresented among ‘problem’ bears near settlements.
We review the mechanisms underlying the occurrence of brown and black bears ( U rsus arctos , U rsus americanus , U rsus thibetanus ) near settlements, and consider four hypotheses designed to separate ultimate and proximate mechanisms.
Increased occurrence of bears near people or settlements can be explained by (i) the human habituation hypothesis; increased use of human‐derived foods can be explained by (ii) the food‐conditioning hypothesis. However, both mechanisms are proximate, because they can only apply if bears have earlier experience of people and/or human‐derived food.
A lack of human experience can explain the increased occurrence of younger bears near people or settlements: (iii) the naivety hypothesis. This is a proximate mechanism, because movements of naive bears are typically triggered by aggression and/or competition among conspecifics.
We conclude that the disproportionate occurrence of bears in certain sex, age and reproductive classes near people or settlements can only be explained by predation avoidance and/or interference competition, i.e. by (iv) the despotic distribution hypothesis. Therefore, a despotic distribution must be an ultimate mechanism causing the proximate mechanisms of habituation or conditioning. Thus, bears using settlements as predation refuges should not be considered ‘unnatural’, but rather as exhibiting an adaptive behaviour, because of the despotic distribution among conspecifics.
Management of LC s includes attractant management, to counteract food conditioning, but failure to consider despotic behaviour among conspecifics may lead to treating only the symptom, e.g. habituation or conditioning. The ultimate cause of attraction to specific settlements may be identified by considering the type of bear involved; the occurrence of large solitary bears near settlements suggests attractive habitat or food shortage in remote areas, whereas subadults and females with cubs suggest lower‐quality habitat.
... Over the last 200,000 years or so human society has embarked on a remarkable socio-evolutionary journey; from hunter-gatherers, to settled agricultural communities and more recently to industrial urban environments. This journey has seen our species move further into a 'human' world and away from what may be defined as a natural world (DeMello 2012;Noth 1998;Bulbeck 2005;Zedrosser et al 2011). This is significant for a number of reasons, not least because the natural world offers a canvas for human cultural expression (DeMello 2012;Noth 1998;Bulbeck 2005;Trigger 2008). ...
... This journey has seen our species move further into a 'human' world and away from what may be defined as a natural world (DeMello 2012;Noth 1998;Bulbeck 2005;Zedrosser et al 2011). This is significant for a number of reasons, not least because the natural world offers a canvas for human cultural expression (DeMello 2012;Noth 1998;Bulbeck 2005;Trigger 2008). More fundamentally, however, we are inextricably linked and dependent upon the natural world for a wide range of resources (DeMello 2012;Oma 2010;Ingold 2006), though given our technological advances, sedentary pastimes and online existence (Soga and Gaston 2016), we appear to have lost sight of this dependency. ...
Bears are iconic animals; they are totemic of the non-human world, symbols of multiple human-cultural manifestations of nature. In human culture, bears have played a number of roles; gods, monsters, kings, fools, brothers, lovers, dancers, medicine, food and pest. They are seen as protectors of the forest; symbols of masculinity; the strength of a fighter, football team or army; a comfort for our children; political bargaining chips; an economic indicator; the first casualty/poster boy of global warming; symbols for conservation; worthy adversaries for a hunter's rifle; prize photography subjects for nature tourists or the last bastion of wilderness. Bears offer a unique insight into a multiplicity of paradigms that explore human-non-human animal relationships. Bear totems reinforce and maintain our connection to the natural world.
Bears and humans have shared a similar geographic journey; as we colonised the world from Africa, bears did so from Europe (albeit a few thousand years earlier), with the brown bear being found most frequently where our species also found hospitable conditions. The ecology of (early) Homo sapiens and Ursus arctos (brown bear) are matched closely: dietary requirements, habitat choice and environmental tolerances. There are many stories that permeate from the past describing our ancestral eaves-dropping on bear foods (and medicines). There are stories of cultures that gathered berries in the same fields as bears and fished on the same rivers: a time when bears and people respected one another's personal space. This is true of some cultures to the present day.
Myths, legends and folklore have informed generations of our and bears’ place in the world. Oral histories passed through generations and through ever-changing norms of communication. From imagined fireside tales to blue-chip documentaries in the 21st century, bears have always been good for us to reflect upon; to ponder our lives in relation to their world, to define our own world, one seemingly at odds to the lives of the other. Bears interweave with many of our cultures.
Cave paintings, sculptures, stories of half-men and monsters, how we perceive bear species can have a huge impact on their survival. Our attitudes towards animals, people and places will shape the face of our planet, our climate and our survival.
... Availability of high quality food near humans increases the chance a brown bear will become habituated. As a result, habituation responses may create "sanctuaries" for subadults and family groups (Olson et al. 1997). However, not all brown bears that forage near humans are habituated; they may just be exhibiting tolerance without a change in the behavior of the bear . ...
... Habituated bears are also more likely to encounter attraction stimuli in the human environment (Hererro 1985). Habituation may then lead to attraction (McCullough 1982, Herrero 1985, Jope 1985, Olson et al. 1997. In learning to ignore people, habituated wildlife have greater opportunities to find attraction stimuli in human environments. ...
... Moreover, higher densities of bears and people in coastal study areas have allowed for de facto or deliberate designs that allow comparison of bear behaviors during periods (or in areas) with versus without human activity. Figure 10 summarizes the results of before-after and control-treatment studies of reactions by coastal grizzly bears to the presence of humans (e.g., Olson et al. 1994Olson et al. , 1997Pitts 2001;Crupi 2003;Smith 2002;Van Dyke 2003;Smith & Johnson 2004;French 2007;Rode et al. 2006aRode et al. , 2007Marshall 2008). In each instance, humans were either absent or relatively scarce in contrast to being present in substantial numbers. ...
... (including Figure 10), although of more direct relevance to displacement, are also relevant to avoidance. Even within classes of bears evincing generally greater avoidance of pedestrians, more tolerant (e.g., "habituated") bears can be differentiated from less tolerant bears, with tolerant bears more often selecting for areas near pedestrians (Olson et al. 1994(Olson et al. , 1997Smith & Johnson 2004). ...
Researchers have documented broadly similar patterns in how grizzly and brown bears respond to people on foot throughout the Northern Hemisphere. Yet there is also substantial documented variation that is plausibly attributable to differences in individual bears, human-bear history, bear-bear interactions, distributions and abundances of people, behaviors of involved people, the predictability of human activity, and the distributions of food resources vis-à-vis humans. And variation can also be found in scaling up from responses of individual bears to responses manifest at an aggregate population level. This report not only elucidates widespread commonalities, but also contextualizes individual and population-level variation revealed in the corpus of research relevant to reactions of brown and grizzly bears to people on foot. The prospectus of this report pertains only to pedestrians or pedestrian-related infrastructure (e.g., trails and backcountry campsites), not motorized human activities (e.g., highway and ATV-track traffic or motor boats and planes), although the boundary is necessarily fuzzy given that some single-track trails support both foot and motorized traffic.
... I examined bear use around Site A looking for daily and seasonal patterns (n =50). I used a metric of bear minutes per observer minute (bm/om) to standardize bear use by observer effort , Olson et al. 1997, Chi 1999 ...
... Regardless of the cause, bears had substantially lower river use near the end of the season. Grizzly bear use at other viewing areas varied throughout the spawning season but was often dictated more by seasonal human activity levels than salmon abundance (Olson et al. 1997, Crupi 2003. Perhaps this seasonal trend will not change once viewing commences at the Fishing Branch River because viewer numbers will be largely constant throughout the viewing season. ...
Wildlife-based ecotourism is rapidly increasing in popularity, especially when featuring large mammals in their natural environment. Researchers have questioned the sustainability of wildlife-based ecotourism because it may compromise the survival and reproduction of focal animals. I investigated the potential spatio-temporal effects of bear viewers on grizzly bears at a proposed bear viewing site along the Fishing Branch River, Yukon. Spatial river use of grizzly bears was largely explained by habituation status. Bears consumed 24% less salmon when viewers were present, posing serious energetic consequences if spatio-temporal compensation does not occur. Dominance status had no measurable effect on bears' fishing behaviour presumably because abundant salmon and few conspecifics minimized resource-driven competition. However, dominance status could influence feeding behaviour in years with reduced salmon abundance, which would compound viewer-induced reductions in fish consumption. I recommend further investigation into spatio-temporal compensatory behaviours of grizzly bears along the Fishing Branch River.
... Bear activity is affected by human presence, and some bears are more responsive than others (Martin et al., 2010;Olson, Gilbert, & Squibb, 1997;Ordiz, Støen, Delibes, & Swenson, 2011;Rode, Farley, & Robbins, 2006a). In particular, females tend to be less sensitive to human presence than males, at least in part because females with cubs appear to use humans as shields against male-induced infanticide (Rode, Farley, & Robbins, 2006b;Steyaert, Kindberg, Swenson, & Zedrosser, 2013;Steyaert et al., 2016). ...
... McNeil rivers in Alaska where bears are relatively easy to observe (e.g., Gill & Helfield, 2012;Olson et al., 1997) or studies relying on abundance proxies such as camera trapping detections (e.g., Levi, Wheat, Allen, & Wilmers, 2015;Quinn et al., 2014;Schindler et al., 2013). Consequently, our understanding of the localized impacts of the salmon subsidy on many coastal bear populations and the extent to which these populations transport marine-derived nutrients into terrestrial food webs remains limited. ...
The interaction between brown bears (Ursus arctos) and Pacific salmon (Oncorhynchus spp.) is important to the population dynamics of both species and a celebrated example of consumer‐mediated nutrient transport. Yet, much of the site‐specific information we have about the bears in this relationship comes from observations at a few highly visible but unrepresentative locations and a small number of radio‐telemetry studies. Consequently, our understanding of brown bear abundance and behavior at more cryptic locations where they commonly feed on salmon, including small spawning streams, remains limited. We employed a noninvasive genetic approach (barbed wire hair snares) over four summers (2012–2015) to document patterns of brown bear abundance and movement among six spawning streams for sockeye salmon, O. nerka, in southwestern Alaska. The streams were grouped into two trios on opposite sides of Lake Aleknagik. Thus, we predicted that most bears would forage within only one trio during the spawning season because of the energetic costs associated with swimming between them or traveling around the lake and show fidelity to particular trios across years because of the benefits of familiarity with local salmon dynamics and stream characteristics. Huggins closed‐capture models based on encounter histories from genotyped hair samples revealed that as many as 41 individuals visited single streams during the annual 6‐week sampling season. Bears also moved freely among trios of streams but rarely moved between these putative foraging neighborhoods, either during or between years. By implication, even small salmon spawning streams can serve as important resources for brown bears, and consistent use of stream neighborhoods by certain bears may play an important role in spatially structuring coastal bear populations. Our findings also underscore the efficacy of noninvasive hair snagging and genetic analysis for examining bear abundance and movements at relatively fine spatial and temporal scales.
... vessel presence, masking of vocalisations by vessel noise, displacement from preferred feeding areas, reduction in food sources, drowning in shark control nets and collisions with vessels (Watkins 1986;Baker and Herman 1989;Duffus 1995;Bannister et al. 1996;Olson et al. 1997;Erbe 2002;Williams et al. 2002;Limpus et al. 2003). ...
... Short-term research on human disturbance of large terrestrial mammals has shown negative impacts such as dispersal from home range, flight responses, reproductive pauses and delayed use of foraging grounds (Duffus 1995;Olson et al. 1997). There is similar potential for marine mammals to be disturbed by human activities. ...
... Despite widespread appreciation of the importance of the bearsalmon relationship for prey, predator, and the ecosystem, behavioral studies have been largely limited to places where bears congregate to capture migrating salmon such as the waterfalls on the McNeil and Brooks rivers in Alaska (Sellers and Aumiller 1994;Olson et al. 1997;Gill and Helfield 2012). These sites do not represent the smaller spawning streams where most predation occurs; observations on such streams are time consuming and often limited to one (Frame 1974;Reimchen 2000) or a very few streams (Gende and Quinn 2004). ...
... In support of this idea, a study in Scandinavia showed avoidance of disturbed areas that was most acute during daytime periods of elevated human activity (Martin et al. 2010). However, some bears (typically subadults) are more tolerant of human presence than others (Olson et al. 1997). Thus, human-driven shifts to crepuscular activity may be manifest unevenly across bear populations and observations during particular periods of the day may not fully represent the abundance or social composition of bear populations. ...
The seasonal and diel movements of predators to take advantage of shifts in prey availability are fundamental elements of their foraging ecology, and also have consequences for the prey populations. In this study, we used complementary noninvasive techniques (motion-activated cameras and hair snares) to investigate seasonal and diel activity of brown bears (Ursus arctos L., 1758) along six proximate streams supporting spawning populations of sockeye salmon (Oncorhynchus nerka (Walbaum in Artedi, 1792)) in southwestern Alaska. Camera records over 3 years showed a rapid increase in bear activity around the time salmon arrived in the streams, with differences among streams corresponding to differences in salmon phenology. Bears were active throughout the day and night, but there were clear crepuscular peaks when camera data were pooled. When wire snares (to collect hair samples) were paired with cameras, the data showed similar seasonal patterns, but each technique detected bears missed by the other. Roughly equal numbers of bears left hair but no camera image, and images but no hair, at paired sites. Taken together, the results indicated a close correspondence between bear activity and salmon timing, differences in diel timing among streams, and the complementarity of data obtained by motion-activated cameras and hair snares.
... Brown bears were observed on salmon streams during all hours of the day, but activity was primarily concentrated during diurnal and crepuscular periods on five of our six study sites. Similar to our findings, brown bears have been shown to be most active during diurnal periods (Stonorov & Stokes 1972;Luque & Stokes 1976), but daily activity levels can vary by age, sex and reproductive status (Olson, Gilbert & Squibb 1997;Klinka & Reimchen 2002). We did observe brown bears to be most active during night-time hours at one of our six sites (C Creek). ...
... hunting vs. scavenging), capture efficiencies and salmon abundances. Additionally, bear activity can be affected by the amount of human activity (Olson, Gilbert & Squibb 1997;MacHutchon et al. 1998;Quinn et al. 2001), as seems to be reflected in the bear activity data from C Creek, which had substantially more human activity on it from our daily fish surveys than other sites where bears were monitored. Taken together, the patterns of salmon movement we observed appears to be coordinated to avoid patterns of bear activity salmon have experienced over their evolutionary history. ...
Daily movements of mobile organisms between habitats in response to changing trade‐offs between predation risk and foraging gains are well established; however, less in known about whether similar tactics are used during reproduction, a time period when many organisms are particularly vulnerable to predators.
We investigated the reproductive behaviour of adult sockeye salmon ( O ncorhynchus nerka ) and the activity of their principal predator, brown bears ( U rsus arctos ), on streams in south‐western Alaska. Specifically, we continuously monitored movements of salmon between lake habitat, where salmon are invulnerable to bears, and three small streams, where salmon spawn and are highly vulnerable to bears. We conducted our study across 2 years that offered a distinct contrast in bear activity and predation rates.
Diel movements by adult sockeye salmon between stream and lake habitat were observed in 51·3% ± 17·7% (mean ± SD) of individuals among years and sites. Fish that moved tended to hold in the lake for most of the day and then migrated into spawning streams during the night, coincident with when bear activity on streams tended to be lowest. Additionally, cyclic movements between lakes and spawning streams were concentrated earlier in the spawning season.
Individuals that exhibited diel movements had longer average reproductive life spans than those who made only one directed movement into a stream. However, the relative effect was dependent on the timing of bear predation, which varied between years. When predation pressure primarily occurred early in the spawning run (i.e., during the height of the diel movements), movers lived 120–310% longer than non‐movers. If predation pressure was concentrated later in the spawning run (i.e. when most movements had ceased), movers only lived 10–60% longer.
Our results suggest a dynamic trade‐off in reproductive strategies of sockeye salmon; adults must be in the stream to reproduce, but must also avoid predation long enough to spawn. Given the interannual variation in the timing and intensity of predation pressure, the advantages of a particular movement strategy will likely vary among years. Regardless, movements by salmon allowed individuals to exploit fine‐scale habitat heterogeneity during reproduction, which appears to be a strategy to reduce predation risk on the spawning grounds.
... By identifying and validating two distinct categories of sharks that are present within the same study system at the same time, we were able to quantify and directly compare the local space use for fed and naïve sharks and in response to feeding activities. We acknowledge that the absence of naïve sharks from feeding events could be due to reasons other than nonresponsiveness towards feeding, such as exclusion from the feeding site due to dominance and/or social hierarchies (Clua et al., 2010;de S a Alves et al., 2013;Fitzpatrick et al., 2011;Maljkovi c & Côt e, 2011), lower nutritional state (Rangel et al., 2022), different dispositions towards habituation (Olson et al., 1997;Titus et al., 2015) or different personalities (Dhellemmes et al., 2020Finger et al., 2017Finger et al., , 2016.While we caution the interpretation of the local space use of naïve sharks as natural, they offer a valid alternative to understand tourism-related feeding impacts on local space use in the absence of behavioural baseline data. ...
Keywords: dynamic Brownian bridge movement model earth mover's distance elasmobranch endangered movement ecology wildlife provisioning By changing the spatiotemporal availability of resources, tourism-related feeding can have potentially detrimental impacts on the movement ecology of animals, thus possibly undermining its own conservation benefits. A lack of baseline data on natural behaviour and the noninclusion of observation data that adequately incorporates the previous experience of animals with tourism-related feeding have generated contradictory results, causing the true impacts of feeding to remain obscure. Further, the relationship between the energy consumption of fed animals and their space use remains unexplored. Here, we coupled passive acoustic telemetry with previously published observation data at a tourism-related feeding site to investigate how direct feeding affects space use and residency patterns of great hammerhead sharks, Sphyrna mokarran, in Bimini, The Bahamas, at various timescales (ranging from days to 8 years). We first constructed movement models for 28 known fed and naïve sharks (i.e. those that were present at the study site but never attended feeding events) to quantify differences in space use and spatial overlap between those groups. We then compared bait uptake of fed sharks with their space use. Fed sharks showed a marked reduction in space use in response to feeding events and an amplification of these impacts over 5 consecutive years. In contrast, naïve shark space use remained unchanged over the same period. The seasonal residency of fed and naïve great hammerheads remained stable across 8 years, with the sharks leaving the study site during the summer of each year. Our study underscores how the intensification of tourism-related direct feeding progressively alters the space use of apex predators across short and long timescales, with enduring effects on fed animals. Our study further highlights the utility of a naïve animal group for assessing feeding impacts in the absence of baseline data.
... Ecosystem health evaluation has received considerable attention in the last three to four decades due to the intensification and expansion of anthropogenic activities, along with their escalating demands on natural ecosystems (Olson et al., 1997;Halpern et al., 2008). Therefore, understanding the key drivers and examining the patterns and processes of wetland ecosystem health dynamics are critical for proper wetland protection (Batunacun et al., 2018;Singh and Sinha, 2021). ...
The focus of the present study was to assess the dynamics of wetland ecosystem health in both urban and rural settings situated in the high-altitude Kashmir Himalayan ecoregion. The basic aim was to identify the drivers responsible for wetland degradation in order to sustain ecosystem services effectively. To achieve this, we examined water quality, trophic status, fish species diversity and human disturbances by analyzing changes in land use and land cover (LULC) since 1980. For the limnological characterization of the two wetlands, we evaluated a total of 21 physico-chemical parameters at 24 sites. Two-way analysis of variance revealed significant (p < 0.05) spatial and temporal variability in the water quality parameters. The trophic state index values of 67.7 and 76.7 indicated that the rural and urban wetlands were in eutrophic and hypertrophic status, respectively, signifying potential environmental stress. The data on fish fauna indicated a decline in fish species over the past 40 years, particularly the schizothoracine species. Urban wetlands showed a more significant decrease in species (06) compared to rural wetlands (01). LULC mapping and change analysis employing the visual interpretation technique showed significant transformations in the immediate catchment of wetlands. Substantial growth in the built-up (334.5 % and 2620 %) and decrease in aquatic vegetation (-83.4 % and - 97.5 %) in the immediate catchment was recorded in both the urban and rural wetlands respectively from 1980 to 2020. Our findings demonstrated a relationship between LULC classes and water quality parameters, with an increase in built-up and road areas showing a significant positive correlation with the rise in decadal mean values of total phosphorus, orthophosphorus, nitrate nitrogen, ammonical nitrogen, and calcium content. Based on these observations, we concluded that changes in land use and land cover within the immediate catchment areas of the wetlands were the primary drivers responsible for the deterioration of wetland ecosystem health.
... By accelerating habitat degradation, these anthropogenic impacts are highly related to extinction risk, especially in terrestrial mammals (Wilson et al., 2016). Human presence can also significantly affect the distribution and/or behavior of wild animals in their natural habitat (e.g., bears: Olson, Gilbert, & Squibb, 1997, Rode, Farley, & Robbins, 2006elk: Whittaker & Knight, 1998; howler monkeys: Grossberg, Treves, & Naughton-Treves, 2003; and gibbons: Reisland & Lambert, 2016). Thus, anthropogenic disturbances confronting wild animals can also be detrimental to the degree of behavioral freedom in the wild. ...
Behavioral freedom is becoming an increasingly important issue bridging animal welfare and conservation biology. This study focused on range size and spatiotemporal variation in Western chimpanzees, creating a novel index for behavioral freedom. Direct observations were conducted on a group of seven free‐ranging chimpanzees in Bossou, Guinea, during 10‐hr observation periods over 10 days, and on a group of five captive individuals at the Kumamoto Sanctuary during 7‐hr observation periods over 7 days. Bossou chimpanzees showed dynamic ranging patterns; their range size was larger, and their day and time‐of‐day ranges did not generally overlap. Additionally, the average time‐of‐day range was 5.2 times greater than the day range. In contrast, sanctuary chimpanzees showed a static ranging pattern, with a smaller range size and a time‐of‐day range to day range ratio of 1.0. Therefore, the time‐of‐day range to day range ratio is a suitable quantitative index of behavioral freedom in chimpanzees.
... As a consequence less time can be spent on feeding (Knight, Anderson, & Marr, 1991;Roe, Leader-Williams, & Dalal-Clayton, 1997), resting and in social interaction (Edington & Edington, 1990). Moreover, off-spring may be abandoned during flight reactions (Stuart-Dick, 1987), and animals may spatially or temporally avoid disturbed habitats even if they sustain better quality resources (Griffiths & van Schaik, 1993;Olson, Gilbert, & Squibb, 1997;Woodall, Woodall, & Bodero, 1989). ...
For nearly a century, researchers have observed the ecological impacts arising from increased numbers of visitors using natural areas for tourism and recreational activities. This study reviews the recreational ecology literature as it is relevant to Sri Lanka providing a rare linkage between global research and local applications of this research. The likely ecological impacts of recreational activities undertaken in natural areas in Sri Lanka are identified with a particular focus on walking/hiking, camping, wildlife watching and motorized activities. We conclude by establishing a research agenda that is relevant for developing countries from the Global South and South Asia that aspire to develop their nature-based tourism industry in a sustainable manner. A particular focus should be on fundamental visitor data collection and relating such data to environmental impacts of specific recreation activities, the establishment of research networks, experimental cause-effect studies, and interdisciplinary studies. We embed this research agenda in a novel conceptual model of the factors and relationships relevant for managing impacts of nature-based tourism as a theoretical contribution to the field of recreational ecology.
... With the enhancement of the ability to change the nature, human activities have widely spread over nearly every corner of the world and been remarkably influencing the natural ecosystem since the 20th century (Olson et al., 1997;Halpern et al., 2008;Liu et al., 2008Liu et al., , 2014aChi et al., 2018a;Li et al., 2018a). Most of these influences, including habitat loss, landscape fragmentation, biodiversity decline, soil erosion, and environmental pollution, have been examined and reported as negative influences; thus, they have elicited increasing attention from the public (Knox, 2001;Nagashima et al., 2002;Flandroy et al., 2018;Liu, 2018;Mahmoud and Gan, 2018;Melaku et al., 2018;Wu et al., 2018a;Kertész et al., 2019). ...
Human activities have widely spread over nearly every corner of the world and been remarkably influencing the natural ecosystem since the 20th century. Identifying and quantifying the negative and positive influences of human activities are important for providing a solid basis for reasonable exploitation and effective conservation. This study focused on the negative and positive influences of human activities on five “macro to micro” aspects of an estuarine ecosystem, including island geomorphology, landscape pattern, plant community, physical quality, and chemical environment. An evaluation model was established using spatiotemporal ecological information from remote sensing, and three new indices, namely, human damage index (HDI), human regulation index (HRI), and human net influence index (HNII), were established to quantify the negative, positive, and net influences of human activities, respectively. Chongming Island in the Yangtze River Estuary of China was used as the study area, and four scenes of remote sensing images in 1988, 1995, 2007, and 2017 served as the data source. Results indicated that HDI initially increased and then decreased, HRI showed generally increasing characteristics, and HNII initially decreased and then increased in the entire study area from 1988 to 2017. Although the net influence was negative, ecological conservation and management since the 21 st century have clearly increased the HNII. Wetland vegetation, mudflat, and woodland had positive HNII; farmland, water area, and pond had HNII close to zero; and building, traffic, and industrial lands possessed negative HNII. The model was proven to greatly contribute to judging the ecological efficiencies of different types of land uses and optimizing the spatial configuration of human activities in estuarine areas.
... Human activities have gradually become the main driving force of global ecosystem degradation in recent decades (Olson and Gilbert, 1997;Chi et al., 2018). River networks have become increasingly degraded, altered, modified, or lost globally due to intense anthropogenic impacts (Florsheim and Mount, 2003;Halpern et al., 2008;Strohbach and Haase, 2012;Chi et al., 2016). ...
... Bears have been known to avoid salmon streams due to human presence [26,27]. To minimize the chance of displacing bears, our cameras were serviced (data cards exchanged) every 10-21 days, mostly during the midday hours (1100-1600) when bear activity along streams tends to be low ( Figure A in S1 File). ...
Aerial surveys are often used to monitor wildlife and fish populations, but rarely are the effects on animal behavior documented. For over 30 years, the Kodiak National Wildlife Refuge has conducted low-altitude aerial surveys to assess Kodiak brown bear (Ursus arctos middendorffi) space use and demographic composition when bears are seasonally congregated near salmon spawning streams in southwestern Kodiak Island, Alaska. Salmon (Oncorhynchus spp.) are an important bear food and salmon runs are brief, so decreases in time spent fishing for salmon may reduce salmon consumption by bears. The goal of this study was to apply different and complementary field methods to evaluate the response of bears to these aerial surveys. Ground-based counts at one stream indicated 62% of bears departed the 200m-wide survey zone in response to aerial surveys, but bear counts returned to pre-survey abundance after only three hours. Although this effect was brief, survey flights occurred during the hours of peak daily bear activity (morning and evening), so the three-hour disruption appeared to result in a 25% decline in cumulative daily detections by 38 time-lapse cameras deployed along 10 salmon streams. Bear responses varied by sex—male bears were much more likely than female bears (with or without cubs) to depart streams and female bears with GPS collars did not move from streams following surveys. Although bears displaced by aerial surveys may consume fewer salmon, the actual effect on their fitness depends on whether they compensate by foraging at other times or by switching to other nutritious resources. Data from complementary sources allows managers to more robustly understand the impacts of surveys and whether their benefits are justified. Similar assessments should be made on alternative techniques such as Unmanned Aerial Vehicles and non-invasive sampling to determine whether they supply equivalent data while limiting bear disturbance.
... Such systematic antipredation behavior associated with a nutritive cost of reduced foraging efficiency over a prolonged period of time may affect the individual fitness of animals (Brown 1999;McArthur et al. 2014). Several studies suggest that human disturbance might disrupt or even restrict bears from utilizing important food sources (Olson, Gilbert, & Squibb 1997;White, Kendall, & Picton 1999;Robbins et al. 2007;. Studies from North America indicate that bears require a high density of berries to enable them to take effective bites, and restricted access to dense berry areas may therefore reduce foraging efficiency (Welch et al. 1997). ...
Animals adapt their foraging behavior to variations in food availability and predation risk. In Sweden, brown bears (Ursus arctos) depend on a nearly continuous intake of berries, especially bilberries (Vaccinium myrtillus) during late summer and early autumn to fatten up prior to hibernation. This overlaps with the bear hunting season that starts on 21 August. Bilberry occurrence varies across space, as does human-induced mortality risk. Here, we hypothesize that brown bears select for areas with a high probability of bilberry occurrence across a boreal forest ecosystem in Sweden (H1), and that human-induced mortality risk reduces bear selection for bilberries (H2). In addition, we hypothesized that bears that survived the hunting season avoided bilberry areas associated with high risk, whereas bears that were later killed selected more strongly for berries and less against risk prior to the hunting season (H3). To evaluate our hypotheses, we used resource selection functions to contrast bear GPS relocation data (N = 35, 2012–2015) and random positions within the bearś home range with generalized linear mixed effect models against two focal variables: a map predicting bilberry occurrence and a map predicting human-induced mortality risk. We found that bears selected for areas with a high probability of bilberry occurrence (supporting H1), but avoided these areas if they were associated with and high risk of hunting mortality (supporting H2). The killed and surviving bears did not differ in their selection for bilberries, but they did differ in their selection against risk (partially supporting H3). Surviving bears strongly avoided high risk areas, whereas killed bears responded less to risk and selected for high-risk areas with a low probability of bilberry occurrence. This suggests that killed bears selected for other food sources than berries in high risk areas, which exposed them to human hunters. We conclude that bears respond to a landscape of fear during the berry season and that different foraging strategies may have a direct impact on individual mortality during the hunting season.
... Ecosystem health and its evaluation have drawn considerable attention with the expansion and intensification of human activities and their increasing pressure on natural ecosystems (Olson et al., 1997;Halpern et al., 2008). In recent years, ecosystem health evaluations have been conducted in different regions and ecosystem types, such as urban and rural areas, forests, basins, wetlands, islands, coastal waters, and oceans, and good results were achieved, thereby providing important references for maintaining ecosystem health in specific areas (Styers et al., 2010;Halpern et al., 2012;Zhang et al., 2013;Li and Li, 2014;Sun et al., 2016;Zhang et al., 2017a;Cheng et al., 2018;Meng et al., 2018;Wu et al., 2018). ...
... Ecosystem health and its evaluation have drawn considerable attention with the expansion and intensification of human activities and their increasing pressure on natural ecosystems (Olson et al., 1997;Halpern et al., 2008). In recent years, ecosystem health evaluations have been conducted in different regions and ecosystem types, such as urban and rural areas, forests, basins, wetlands, islands, coastal waters, and oceans, and good results were achieved, thereby providing important references for maintaining ecosystem health in specific areas (Styers et al., 2010;Halpern et al., 2012;Zhang et al., 2013;Li and Li, 2014;Sun et al., 2016;Zhang et al., 2017a;Cheng et al., 2018;Meng et al., 2018;Wu et al., 2018). ...
The evaluation of estuarine wetland ecosystem health (EWEH) is vital and difficult due to complex influencing factors and their spatial heterogeneities. An EWEH evaluation model was established in this study on the basis of the typical features of estuarine wetland ecosystems with focus on spatial heterogeneity. The index system comprises external factors, internal factors, and ecological state, and covers all aspects of the natural and anthropogenic factors, with each index possessing its own spatial heterogeneity. The Yellow River Delta, a typical estuarine wetland in China, was selected as the study area to demonstrate the model. Results indicated that the present EWEH in the entire study area was in good status with distinct spatial heterogeneity. Ecosystem productivity, seawater intrusion, human interference, and Yellow River input were the most relevant indexes of EWEH. The temporal variations of EWEH fluctuated from 1987 to 2016. The decrease in the Yellow River input and the increase in human activity intensity deteriorated EWEH, whereas the alongshore embankment and nature reserve construction improved EWEH in certain parts. The influence of natural factors continuously decreased, and human activity became the main driving factor of the EWEH spatial variation. Our model was proven to possess comprehensive reflections of estuarine wetland ecological characteristics, full exhibitions of spatial heterogeneity, and high applicability; therefore, it can be widely used to evaluate EWEH in different areas.
... Human activities have gradually become the main driving force of global ecosystem degradation since the mid-20th century (Simpson and Christensen, 1997;Olson et al., 1997;Franoise and Jacques, 2003). At present, human activities have spread worldwide and profoundly influenced the natural ecosystems (Halpern et al., 2008;Strohbach and Haase, 2012;Chi et al., 2016Chi et al., , 2017a. ...
The accurate quantification and spatial evaluation of human activity intensity is highly significant for determining the resource and environment carrying capacities of coastal areas. A human interference index (HII) was established in our study based on the minimum and maximum influences of exploitation types, the different ecological conditions within the same exploitation type and the buffer effect of exploitation on adjacent areas. It was characterized by the comprehensive consideration of the ecological features and their spatial heterogeneity. To validate the accuracy and applicability of HII, the Yellow River Delta was selected as the study area, with the years of 1987, 1995, 2005 and 2016 as the temporal scope. Then, to clarify the ecological significance of HII, the relationships of landscape pattern, vegetation net primary productivity (NPP) and soil property with HII were analyzed. The HII of the study area exhibited a continuous increase and spatial heterogeneities from 1987 to 2016. The proportion of the little interference zone kept on decreasing, the proportions of the intermediate, severe and very severe interference zones continued increasing, and the proportion of the mild interference zone initially increased and then slightly decreased. Human interference spread continuously and has been the main driving factor of ecosystem change. The HII is significantly positively correlated with patch density, edge density, and soil salinity, and negatively correlated with NPP and soil moisture content. The HII was proven to possess high accuracy, good applicability and considerable ecological significance. Therefore, it can be widely used in the evaluation of human activity intensity in coastal areas.
... Regular exposure of wildlife to anthropogenic food resources may not just set the stage for localized conflict-it may also foster the development of "problem" behavior such as stock-killing or cropraiding and increase the physical risk of attacks on humans and their pets (Woodroffe et al. 2005a). Human presence affects the habituation behavior of brown bears, resulting in an increase in negative encounters with humans, including fatal accidents (North America: Mattson et al. 1987Mattson et al. , 1992Olson et al. 1997;Herrero et al. 2005, Europe: Rauer et al. 2003Martin et al. 2010). Recent adaptation to urban and suburban habitats likely took place over several generations, and such adaptation may have involved learned behaviors passed from parent to offspring (Baker and Timm 1998). ...
Recently, brown bears have moved deeper inside urban areas in Sapporo, the fifth-largest city with a population of 1.9 million in Japan. Here, I review urban large carnivore management and its human dimension and discuss how to create a model of harmonious coexistence that includes both management of human-brown bear conflict (HBC) and conservation of the lush, green environment of Sapporo. Although large carnivores that use urban landscapes can temporarily obtain an abundance of high-energy foods, they are also subject to high rates of human-derived mortality. Brown bear invasions of the city center of Sapporo are still rare and are likely caused by bear population increase and distribution expansion within the last decade. It is important to manage urban borders to reduce their attractiveness. A verdant environment and biodiversity conservation are considered to be important to urban residents in Sapporo. Urban HBC, however, is an unavoidable consequence of this style of living. Because a variety of stakeholders affected by HBC and its management live in the city, their various values should be reflected in wildlife management policy through a more collaborative, community-based decision-making model.
... Yet, recent research suggests that bears perceive humans as a risk and respond with typical anti-predator behaviours (Ordiz et al., 2011;Støen et al., 2015), such as changes in vigilance or displacement (Nevin and Gilbert, 2005a;Rode et al., 2006b), even at well-established bear viewing sites (e.g. Braaten and Gilbert, 1987;Olson et al., 1997;Chi, 1999). Rode et al. (2006a) made two other important suggestions for regulations that should be implemented in the use of viewing sites, especially if they are located in close proximity to bears (from dozens to a few hundred metres). ...
... This agrees with the report by Crupi (2003) that noted the displacement of most bears from foraging activities during the day by human presence and vehicular movements. This finding is further substantiated by the works of Olson et al. (1997) and MacHutcheon et al. (1998) that independently reported the adjustment of diurnal and seasonal activities of most mammals in response to human presence. This finding further corroborates the report by Rogala et al. (2011) that changes in habitat pattern in response to increased human activities can have serious implications on animal ecology and their community interactions. ...
There is inadequate information on the population characteristics of the endangered Mandrillus leucophaeus in Nigeria. Thus, a study on the population status of the species was conducted in Afi Mountain Wildlife Sanctuary, Southern Nigeria. Data were collected from twelve randomly located transects each from the Northern and Southern Blocks of the area using Distance sampling technique. Each transect was walked 8 times (making a total of 192 km survey efforts) only during the day. Sighting and perpendicular distances were obtained using laser rangefinder. Data were analyzed using DISTANCE 6.0 to compute density, encounter rate and abundance with the Akaike information criterion as the model selection criterion. The student t-statistics was used to compare the sighting distances between the two management blocks. The result showed that there was no significant difference (P > 0.05) in mean sighting distances between the two blocks. A total of 210 individuals were sighted in the area. About 56% (118) of the sightings were recorded in the Northern Block while 44% (92) were in the Southern Block. The mean encounter rates were 0.95 km-2 and 0.77 km-2 for the Northern and Southern Blocks respectively, and the estimated densities were 7 km-2 and 6 km-2 for the Northern and Southern Blocks with species abundance of 367 and 300 individuals respectively. The estimated species abundance in the entire area was 669 individuals with MER and density of 0.95 km-2 and 6 km-2 respectively. Protection efforts should be stepped up to ensure adequate protection of drills in the area, as there were signs of encroachment with evidence of hunting exemplified by spent cartridges.
... For example, while MacHutchon et al. (1993) attempted to capture Grizzly Bears across a wide range of elevations, most bears in that study were trapped below 200 m ASL and none were trapped at alpine or subalpine locations. Second, traditional concentrations of Grizzly Bears at salmon-fishing sites are well known (e.g., Brooks River in Katmai National Park, Alaska; Olson et al. 1997). Third, the high nutrient and energy content of salmon makes it likely that many Grizzly Bears would seek this food source. ...
While conducting surveys for Mountain Goats (Oreamnos americanus) in seven mountain blocks covering 3019 km 2 in westcentral British Columbia during autumn 1996, 57 Grizzly Bears (Ursus arctos) were observed in 34 groups consisting of 1-4 individuals. Grizzly Bears were observed at alpine and high subalpine elevations. It was likely that many of those bears did not forage on runs of spawning salmon (Oncorhynchus spp.) in the valley bottoms, thereby further demonstrating the value of higher-elevation habitats for some "coastal" Grizzly Bears during autumn.
... Although revenue from tourism is providing economic support for nonconsumptive use of high-profile wildlife such as whale sharks (Davies 1990, Graham 2003, tourism is not always the panacea of wildlife conservation, as it can negatively impact the animals (Olson et al. 1997, Butynski and Kalina 1998, Isaacs 2000, Orams 2000. Recent declines in whale shark sightings at Gladden Spit are perhaps linked to the increase in number of divers and boats at the aggregation site. ...
... Similarly, the responses of mammalian carnivores to recreation may vary by species (George and Crooks 2006). Human recreation may affect wildlife activity, reproduction, and survival (Knight and Gutzwiller 1995;Whittaker and Knight 1998), it can cause higher energetic costs due to alarmed responses (Miller et al. 2001;Papouchis et al. 2001;Taylor and Knight 2003), and it can alter carnivore behavior and distribution (Olson et al. 1997;White et al. 1999;Nevin and Gilbert 2005;George and Crooks 2006). Reed andMerenlender (2008, 2011) found significant differences in carnivore composition and relative abundances between protected areas with and without quiet nonconsumptive recreation. ...
Mammalian carnivores are affected by various anthropogenic disturbances near urban environments. Urban expansion and increased anthropogenic activity near and in preserved habitats may cause shifts in the current spatial distributions of those species. To predict the effects of future land-use changes on mammalian carnivores, we modeled their current occurrence across former Fort Ord Army Base as a function of urban proximity and road/trail density. We collected detection/nondetection data for domestic dogs, coyotes (Canis latrans), gray foxes (Urocyon cinereoargenteus), raccoons (Procyon lotor), striped skunks (Mephitis mephitis), and bobcats (Lynx rufus) using scent stations. We analyzed our data with likelihood-based occupancy modeling and used evidence ratios based on Akaike information criterion weights to infer the effect of each variable on occurrence and detection probabilities for each species. We used the estimated weighted model coefficients of the predictive variables to create current and future species distribution maps given proposed landscape changes in the study area. Domestic dogs were more likely to use areas closer to the urban edge, while gray foxes showed a preference toward inland areas. Detection probability was highest in areas closer to the urban edge for striped skunks and in areas with high road/trail densities for raccoons. Our results suggest that the distribution of domestic dogs will most likely expand with future development, while those of gray foxes will contract. We predict that future land-use changes outside of preserved areas will have an adverse effect on gray foxes within the protected areas.
... Development actions that could impact salmon consumptions by bears include changes in land use, river improvements and large-scale industrial fishing. Brown bears generally tend to avoid human facilities such as paved roads 20 . Changes in land use such as the construction of paved roads, expansion of urban areas and farmland are primary factors for reclamations and occur concurrently with the progression of development. ...
Human activities have had the strongest impacts on natural ecosystems since the last glacial period, including the alteration of interspecific relationships such as food webs. In this paper, we present a historical record of major alterations of trophic structure by revealing millennium-scale dietary shifts of brown bears (Ursus arctos) on the Hokkaido islands, Japan, using carbon, nitrogen, and sulfur stable isotope analysis. Dietary analysis of brown bears revealed that salmon consumption by bears in the eastern region of Hokkaido significantly decreased from 19% to 8%. In addition, consumption of terrestrial animals decreased from 56% to 5% in western region, and 64% to 8% in eastern region. These dietary shifts are likely to have occurred in the last approximately 100-200 years, which coincides with the beginning of modernisation in this region. Our results suggest that human activities have caused an alteration in the trophic structure of brown bears in the Hokkaido islands. This alteration includes a major decline in the marine-terrestrial linkage in eastern region, and a loss of indirect-interactions between bears and wolves, because the interactions potentially enhanced deer predation by brown bears.
... Similarly, contingent valuation has added non-market values to wilderness landscape that are trivial (less than $100 per hectare) on the watershed scale (Reid et al. 1995 (Tollefson et al. 2005). For example, the well-known Brooks River in Katmai National Park lists 40 plane operators offering access and more than 10,000 visitors annually (Olson et al. 1997). ...
Extreme sports, adventure, and ecotourism are bringing increasing numbers of people into remote backcountry areas worldwide. The number of people visiting wilderness areas is set to increase further, and nature tourism is the fastest growing sector in the $3.5 trillion global annual tourism market (Mehmetoglu 2006). What impacts will this have on the social perceptions, economic, and conservation values of these areas and the species that are found there? Reflecting on over a decade's research on the impacts of the bear-viewing (Ursus spp.) ecotourism industry in British Columbia, Canada, this paper considers authenticity, place, and 'place making' via a case study of bear tourism in British Columbia (B. C.), Canada.
... Although revenue from tourism is providing economic support for nonconsumptive use of high-profile wildlife such as whale sharks (Davies 1990, Graham 2003, tourism is not always the panacea of wildlife conservation, as it can negatively impact the animals (Olson et al. 1997, Butynski and Kalina 1998, Isaacs 2000, Orams 2000. Recent declines in whale shark sightings at Gladden Spit are perhaps linked to the increase in number of divers and boats at the aggregation site. ...
The fisheries White sharks Carcharodon carcharias are widely distributed within New Zealand's exclusive economic zone (EEZ), occurring in coastal and oceanic waters from at least 33 o S to 52.5 o S, and are taken in a number of non-commercial and commercial fisheries. Recreational and customary fishers mainly take white sharks as bycatch in gillnets, and occasionally on longlines (Duffy unpubl. data). Sport fisheries for white sharks in New Zealand are largely undeveloped and fishers often tag and release those they do catch (Mossman 1993; Wilson 2002). A protective beach meshing programme run by Dunedin City Council (DCC) operates seasonally off Brighton, St. Clair and St. Kilda beaches. Although targeted, no white sharks have been taken since 1975. All sharks taken are disposed of at sea unless requested for research (L. Bell, DCC, pers. comm.). White sharks are not considered capable of sustaining a target fishery in New Zealand and commercial fisheries regulations prohibit directed fisheries (Francis 1998). They are taken as bycatch, however, in bottom-set longline, dropline and gill net fisheries, and occasionally in trawl and tuna longline fisheries (Ministry of Fisheries Catch Effort Database, Duffy unpubl. data). Landings and sale of bycatch is permitted.
... The observation that AB bears forage closer to cover than those in NB corroborates the conclusion that they are more wary and risk averse. It is well documented that bears avoid areas where human activity levels result in harassment (Ayers et al. 1986, Mattson 1990, Chi and Gilbert 1999 and that responses may be numerical or behavioral (Olson et al. 1997, Rode et al. 2006. Since the main difference between the 2 areas is levels of human activity, we feel it is likely responsible for the differential wariness observed. ...
We measured American black bear (Ursus americanus) responses to hikers, small power skiffs, kayakers, and overnight campsites within coastal salt marsh foraging areas. To accomplish this, we experimentally approached bears in the intertidal and supratidal zones of Aialik Bay (AB) and Nuka Bay (NB), Kenai Fjords National Park, Alaska. We chose these areas due to their different levels of human activity (AB = high, NB = low). In the first experiments, we determined the overt response distances (ORD: when bears first responded to our approaches) and flight initiation distances (FID: the distance at which bears were pushed from their original location) for 118 black bear groups involving 136 bears. We found no difference between ORD response to power skiffs and versus kayaks, nor between those responding to kayaks versus foot approaches. However, bears first responded to power skiffs 50 m farther than first responses to foot approaches. There was no difference in FID between all modes of approach. There were no differences in response intensities (a qualitative scale depicting strength of bear response to human presence at both the ORD and FID) between any of the modes of approach. There were no differences in bear minutes/hour (minutes of bear presence in the study area/hour of observation) or numbers of bears at NB and AB before or after campsites were present. There was, however, a difference in levels of bear activity in NB and AB when campsites were in place: AB bear minutes/hour decreased by 50% and NB bear minutes/hour increased by 75%. We recommend minimum approach distances of 170 m for skiffs and kayaks and 116 m for hikers to minimize bear displacement by visitors to the park. Additionally, we suggest people avoid camping in saltmarsh areas so as to leave bears undisturbed.
... Wildlife viewing can impact grizzly bears in the short-term at the individual level, and in the long-term at the population level, as impacts become cumulative (Green and Geise 2004). Potential short-term impacts resulting from increased human presence in grizzly bear habitat include habituation of individuals (Government of British Columbia 1993; Nevin and others 2001; Swenson 1999), habitat displacement (Gibeau and others 2002; Nevin and Gilbert 2005; Olson and others 1997), and adjustments in behavioral patterns (Klinka and Reimchen 2002; Naves and others 2001; Reimchen 1998; Smith 2002). ...
Wildlife viewing, a growing industry throughout North America, holds much potential for increased revenue and public awareness regarding species conservation. In Alaska and British Columbia, grizzly bear (Ursus arctos) viewing is becoming more popular, attracting tourists from around the world. Viewing is typically done from a land-based observation platform that forces tourists into a centralized location. Studies addressing the impacts of tourism on grizzly bear population fitness have based data col- lection from similar platforms or towers that overlook the entire viewing area. In larger study areas, this may not be possible. In the K'tzim-a-deen Valley, all viewing is done from boats, thus changing the dynamics of tourism. The impacts of boat-based tourism are likely different than those of land-based tourism; therefore, this research attempted to quantify the former so that the two can be compared. Data collection that focused on grizzly bear behavior was accomplished from a small boat. With this new methodological ap- proach different challenges arose that required innovative solutions in the field. This paper outlines a new boat-based methodology and its associated challenges, for studying the impacts of boat-based viewing on grizzly bears.
... These sites were relatively free of anthropogenic influence and supported healthy populations of salmon (Halupka et al. 2000) and bears (Beier et al. 1996). Many of the published and publicized observations of bears fishing for salmon have occurred at the McNeil River Falls (e.g., Sellers and Aumiller 1994;Olson et al. 1997) and Brooks Falls in Alaska. These sites are unusual because salmon availability is concentrated at waterfalls (deep water prohibits successful fishing elsewhere) that salmon negotiate on their migration to spawning sites farther upriver. ...
We quantified foraging behavior of brown bears (Ursus arctos) feeding on adult chum (Oncorhynchus keta) and pink salmon (Oncorhynchus gorbuscha) at three small coastal streams in southeastern Alaska from streamside tree stands. These observations revealed that social dominance was much more important in determining intake rates among bears than salmon densities. Each small stream supported one large, socially dominant bear that directly displaced other bears in aggressive encounters or was avoided in "passive deferrals". Although the number of fish killed per foraging bout was positively correlated with salmon density, energy intake was determined primarily by foraging effort, as dominant bears visited the stream more often and foraged for longer periods than subdominant bears. Capture efficiency (fish captured per minute searching) was highly variable and increased only marginally with salmon density and among social ranks. Subdominant bears were more vigilant, used a smaller fraction of each stream, and carried salmon much farther into the forest prior to consumption, presumably to minimize interactions with other bears. Social dominance may play an important role in regulating reproductive success when salmon densities are low and may have important implications for managers in bear-viewing areas.
... Consequently, a significant amount of research on the biological impacts of wildlife viewing has been undertaken in recent years, especially studies in areas of bear congregations that have focused on aspects of the bears' behaviour (Aumiller & Matt, 1994;Dyck & Baydack, 2004;Fagen & Fagen, 1994;Olson et al., 1997;Watts & Ratson, 1989), their management (Dalle-Molle & Van Horn, 1989), and denning patterns (Ramsay & Stirling, 1982, 1990. For example, studies conducted on Churchill's polar bear viewing industry found that while vigilance among sub-adult bears does appear to increase in the presence of humans, the increase is quite small (Dyck & Baydack, 2004;Watts & Ratson, 1989). ...
Despite the recent growth of wildlife viewing, research on the human dimensions of wildlife tourism in protected areas has been limited. This is surprising because if no monitoring is done, then understanding and responding appropriately to both the benefits and impacts of wildlife tourism in protected areas is almost impossible. In this study, data were gathered on the character of organised outings made by wildlife viewers visiting Churchill, Manitoba to see polar bears in situ. The purpose of the study was to examine the effect of selected environmental factors, such as numbers of wildlife seen, amount of wildlife activity, and overall visibility, on the social dynamics and experience of the wildlife tourists. Results indicate that the number of polar bears seen is the only factor directly related to viewer attentiveness and group dynamics, and importantly, on-site satisfaction with the experience.
... Human-caused habitat fragmentation may potentially influence the recolonization of former bear habitat (Gaines, 2003;Apps et al., 2004;Johnson et al., 2004;Proctor et al., 2005). Currently, little is known about how the large-scale development of outdoor recreational resorts and construction of second-home cabins may be influencing the availability and quality of bear habitat (Elgmork, 1978(Elgmork, , 1983(Elgmork, , 1994Mattson et al., 1992;Olson et al., 1997;Gibeau et al., 2002;Boyce and Waller, 2003;Apps et al., 2004). Studies from 1949 to 1978 in Norway clearly suggested lower abundance of bears near cabin development in a declining population (Elgmork, 1978(Elgmork, , 1983, but little is known whether this pattern also applies to the growing bear populations observed today. ...
This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem (see Appendix 1 for scientific names). Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model (CEM) to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977–96) on the foraging behavior of Yellowstone’s bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. This information on foraging behavior and energetics was used to estimate the average digestible energy obtained from foods at a given type of feedsite, subtracting the energy that was expended. This estimate of net digested energy was then coupled with an estimate of the density of bear activity in each of 18 habitat types to produce, in turn, a relative measure of the total net digested energy obtained by grizzly bears from each habitat type.
Our compilation provides a geographical, chronological, and qualitative overview of these encounters, reviews both humans' and dolphins' deleterious behaviors during interspecific interactions and summarizes the main risks to both humans and dolphins during close encounters. Based on this review, we outline and discuss how both animal welfare and human safety should be managed such that these activities are sustainable; the demand for personal wildlife experiences continues to grow at an alarming rate and the economic pressures placed on wild animal populations run the risk of damaging the very environmental assets that support this industry if they cannot be managed effectively.
Park managers in Canada's Rocky Mountain National Parks are continually challenged to balance visitor needs with those of grizzly bears. While research pertaining to grizzly bear habitat requirements is abundant, human dimensions' research examining the perspectives and expectations of the trail user is not. Guided by principles of behavior intention and its influence on management support, we assessed trail user support for management options regarding grizzly bears in Banff, Jasper, Kootenay, and Yoho National Parks in Canada using an intercept survey. The main findings were in line with predictions, trail users were more supportive of restrictive management options e.g., closing the trail when a female grizzly bear with cubs was in the area rather than a solitary bear; and management options pertaining to modifying bear behavior were largely opposed. Local users who live within these protected areas or who use them daily were less supportive of restrictive management options compared with other trail users. The research supports the proposal that specificity may be an important factor in determining stakeholder beliefs for intervention design. Identification of key influencing factors in the selection of management options for diverse groups of trail users is important if the needs of trail users and grizzly bears are to be managed in a sustainable and risk-sensitive manner.
Adventure tourism numbers are estimated for Alaska and the impacts on wildlife are considered in detail. This wildlife includes: black and brown bears, bear-viewing tourism and its management approaches; the impacts on Dall sheep; the effects of winter recreation on ungulates, including mountain caribou; the recreational impacts on bird populations, including bald eagles, black oystercatchers and marbled murrelets; and whale-watching and harbour seal impacts. The effects of recreation caused by camping, hiking trampling pressure on tundra, the invasive plant spread along trails and the development of informal trails in Arctic wildlife refuges are considered. The impacts of off-road vehicles on tundra, helicopter-supported recreation impacts and the effects of waste produced by climbers on Mount McKinley are evaluated. Finally, the effects of recreational fishing and some impacts on native human populations are discussed.
State parks are typically established to preserve natural or native habitats for wildlife while simultaneously providing recreational experiences for humans. However, because of their proximity to urban centers, the level of human visitation associated with state parks may be highly variable. Little information has been published regarding the effect of human visitation levels on wildlife escape behavior in state parks. We evaluated flight initiation distances (FIDs) and buffer distances (i.e., the difference between alert and flight distances) for white-tailed deer (Odocoileus virginianus; deer) from September 2013 to August 2014 at 3 state parks in east-central Illinois with different human visitation rates. Deer FIDs were lower in a high-visitation park and higher in a low-visitation park. The buffer distances were higher in a high-visitation park and lower in a low-visitation park. Other social (sex, group size, presence of juveniles) and environmental (cover, weather, season) variables that might affect escape behavior did not account for the relationships with park attendance. These results suggest that deer within state parks either habituate to human activity or spatially segregate based on personality (e.g., degree of shyness or boldness). Based on our findings, high levels of human visitation in parks can have a significant impact on the behavior of local wildlife.
119-page bibliography of works cited in in CARNIVORE CONSERVATION, edited by John L. Gittleman, Stephan M. Funk, David Macdonald, and Robert K. Wayne, Cambridge University Press, 2001.
Includes approximately 2,000 items.
This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yel-lowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977–96) on the foraging behavior of Yellowstone's bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. Coefficients were calculated for different time periods and different habitat types, specific to different parts of the Yellowstone ecosystem. Stratifications included four seasons of bear activity (spring, estrus, early hyperphagia, late hyper-phagia), years when ungulate carrion and whitebark pine seed crops were abundant versus not, areas adjacent to (<100 m) or far away from forest/nonforest edges, and areas inside or outside of ungulate winter ranges. Densities of bear activity in each region, habitat type, and time period were incorporated into calculations, controlling for the effects of proximity to human facilities. The coefficients described in this report and associated estimates of grizzly bear habitat productivity are unique among many efforts to model the conditions of bear habitat because calculations include information on energetics derived from the observed behavior of radio-marked bears.
Human disturbance is caused by the mere presence of humans in the environment.As both predation risk and human disturbance redirect time and energy from other fitness-enhancing activities such as reproduction and feeding, perceived predation risk appears to be useful in the understanding of the impact of human disturbance. It is essential to understand how birds react to different levels of human disturbance because riskier human behaviour can have devastating effects on habitat use, community composition, reproduction and fitness. Birds tend to overestimate the risk associated with humans rather than underestimate it and risk injury and therefore are more likely to partially habituate to harmless and repetitive human disturbance rather than lose all 'fear' towards humans. As a bird's response dynamically varies with its current assessment of risk and the response is most likely to be context and species-specific, it is difficult to predict with confidence, how birds will react to increased incidences of human disturbance.
A voluntary “rest period” to supplement mandatory regulations off Kaikoura, New Zealand, was effective in reducing, but not eliminating vessel traffic around dolphin groups. The non-rest periods had a mean of 2.63 interactions/h, significantly more than the rest period's mean 1.46 interactions/h. Mean interactions per hour during rest and non-rest periods was significantly different for weekdays, but not for weekends. Without education that targets users on the presence of voluntary codes of conduct, why they were developed and the benefits to the animals and community in following the regulations, it is unlikely that participation will be sustained.
We studied the relationship between human development and activity, and subadult grizzly bears (Ursus arctos) by comparing the distribution of radiotelemetry locations from 23 subadult versus 29 adult grizzly bears during 1994–2000 in the Bow River Watershed of Alberta, Canada. We used logistic regression to model significant differences in the spatial distribution of subadult and adult grizzly bears and analysis of variance (ANOVA) to test for significant differences in temporal distribution. Subadult bears were significantly closer to high-use roads and at lower elevations than adult bears. Both subadult and adult bears were significantly closer to high-use roads and at lower elevations during human inactive periods (1800–0700) than during human active periods (0700–1800). Subadult bears were closer to high-use roads regardless of the time of day, and therefore predisposed to greater encounter rates with humans. Consequently, subadult bears had a greater chance of becoming habituated to humans and of being killed or removed from the population by humans than adult bears. In areas with high levels of human use, we recommend that grizzly bear managers consider the population effects of these losses.
Salmon (Oncorhynchus spp.) are an important resource for terrestrial wildlife. However, the salmon requirements of wildlife populations and the role wildlife play in nutrient transport across ecosystems are largely ignored in salmon and habitat management. Any activity that reduces the availability of or access to salmon by wildlife may adversely affect wildlife populations and, potentially, ecosystem-level processes. Thus, when the conservation of specific wildlife populations or healthy ecosystems is the management objective, allocation of salmon to wildlife should be considered. We provide an example of how such allocations could be calculated for a hypothetical bear population. Ultimately, salmon allocation for wildlife calls for integrated management of natural resources across agencies, across species, and across ecosystems. We summarize the current state of knowledge relative to the interaction between Pacific salmon and the terrestrial ecosystem, with special emphasis on the import of salmon to terrestrial wildlife and the import of wildlife to terrestrial and aquatic ecosystems.
Brown bear (Ursus arctos) activity along salmon (Oncorhynchus spp.) streams has frequently been characterized as crepuscular. Suggested explanations include: responses to daily changes in salmon abundance, responses to daily cycles of light and temperature, natural feeding schedules, and avoidance of people. We investigated the last hypothesis by comparing bear activity at 2 adjacent streams in Katmai National Park, both spawning habitat for the same run of sockeye salmon (Oncorhynchus nerka) but differing in their levels of human use. During 1989 and 1991, bear activity at Margot Creek, where no human activity was observed, was distributed uniformly throughout the day (based on 240 observation hours; P > 0.90 both years). This uniform distribution contrasted with the crepuscular pattern of bear activity observed at Brooks River, where human use came from a 60-person lodge, a 60-person campground (20 sites), and substantial day-use. Significant differences (P < 0.001) in activity by time of day were found at Brooks River during the autumn salmon spawning period (sampled 1988-92,905 observation hr). The midday depression in activity was greatest for bears less tolerant of people (>68% of the adult bears seen). As human activity increased over the years of the study, these shier bears shifted their stream use among time periods: midday activity decreased while activity during the 2000-2200 hour time block increased significantly (P < 0.050). Our results indicated that avoidance of people cannot be discounted as a factor contributing to observed crepuscular patterns of use in brown bears.
Aerial locations of radio-instrumented grizzly bears (Ursus arctos) were used to analyze effects of human activity associated with developments and primary roads on grizzly bear habitat use in Yellowstone National Park. Grizzly bear occupancy of habitat near human facilities was reduced, efficient foraging strategies were disrupted, and cohorts tending to be subordinate or security-conscious were displaced into habitat nearer developments by more dominant cohorts, particularly during summer and fall. Adult females and subadult males residing closer to developments were management-trapped at a higher rate than animals of the same class residing farther away. Adult females and subadults bore a disproportionate part of costs associated with avoiding roads and developments. For this reason and because adult females are generally thought to operate under considerable energetic duress in the Yellowstone area, avoidance of developments and roads may have resulted in higher mortality and lower productivity among the adult female cohort.
Visual observations were used to determine if human recreational activity affected grizzly bear (Ursus arctos horribilis) use of open meadow areas in Pelican Valley, Yellowstone National Park. Visitor compliance with bear management regulations and safety warnings were also evaluated. From May-September 1984-88, 944 bear observations were recorded. During this period, the study area was managed for 3 levels of backcountry use: open (both day use and overnight camping allowed), restricted use (day use only), and closed (no visitor use allowed). The average flight distance of grizzly bears to tree cover following disturbance by backcountry users was 422 m. When the valley was open to visitors, bear activity in areas greater than 500 m from forest cover was significantly reduced and bears avoided areas around occupied backcountry campsites. No differences in diurnal hourly activity patterns were observed among the open, restricted, and closed periods. Foot parties were more likely to be charged during an encounter with a grizzly bear than people on horseback. All incidents in which hikers were charged by bears involved groups of 1 or 2 people. Only 17% of the observed hiking parties followed the recommended group size of 4 or more people. Compliance with the area closure and day use only regulations was 99% and 83%, respectively.
The sex, age, and other characteristics of 668 brown bears (Ursus arctos) killed in nonsport circumstances in Alaska during the period 1970-85 were examined. These data represent an unknown fraction of total nonsport kills as not all kills were reported. Both sport harvests and nonsport kills are increasing in Alaska. Nonsport harvests averaged 5.1% of total sport and nonsport kills. Areas with the highest human density had the highest ratio of nonsport to sport harvests. Nonsport harvests are most common during periods when most people are in remote areas to hunt or fish. Males predominate in the nonsport kills of younger bears and females in the nonsport kills of older bears. Regulations and other factors make adult male bears more vulnerable to sport hunters than adult female bears. Partially as a result, nonsport kills contain more adult females than sport kills. An analysis based on affidavits from 224 persons killing bears revealed that bears were shot to avoid perceived danger (72%), to protect property (21%), and to eliminate nuisances (7%). Int. Conf. Bear Res. and Manage. 7:51-58 Human presence in bear habitat usually leads to conflicts between bears and people, frequently with fatal consequences for the bear but rarely leading to injury or death for the person (Herrero 1985). In all of the United States except Alaska, brown-grizzly bears (hereafter brown bears) are so rare that the incidence of such contacts is too small to permit thorough analyses of the characteristics of the bear subpopulation that comes into conflict with humans. Herrero (1985) studied circumstances in which brown bears caused injuries to humans, and others examined circumstances where bears caused depredation prob- lems (Murie 1948, Johnson and Griffel 1982, Jor- gensen 1983, Knight and Judd 1983). Greer (1981) investigated deaths of Montana and Wyoming grizzly bears in nonsport circumstances. Jope (1983) pre-
Human effects on bear habitat use are mediated through food biomass changes, bear tolerance of humans and their impacts, and human tolerance of bears. Large- scale changes in bear food biomass have been caused by conversion of wildlands and waterways to intensive human use, and by the introduction of exotic pathogens. Bears consume virtually all human foods that have been established in former wildlands, but bear use has been limited by access. Air pollution has also affected bear food biomass on a small scale and is likely to have major future impacts on bear habitat through climatic warming. Major changes in disturbance cycles and landscape mosaics wrought by humans have further altered temporal and spatial pulses of bear food production. These changes have brought short-term benefits in places, but have also added long-term stresses to most bear populations. Although bears tend to avoid humans, they will also use exotic and native foods in close proximity to humans. Subadult males and adult females are more often impelled to forage closer to humans because of their energetic predicament and because more secure sites are often preempted by adult males. Although male bears are typically responsible for most livestock predation, adult females and subadult males are more likely to be habitu- ated to humans because they tend to forage closer to humans. Elimination of human-habituated bears predictably reduces effective carrying capacity and is more likely to be a factor in preserving bear populations where humans are present in moderate-to-high densities. If humans desire to preserve viable bear populations, they will either have to accept increased risk of injury associated with preserving habituated animals, or continue to crop habituated bears while at the same time preserving large tracts of wildlands free from significant human intrusion. Humans (Homo sapiens) have preempted a large part of the Earth for their use. The attendant transformation and depletion of ecosystems has resulted in extinction rates comparable to any prehistoric mass extinctions. Increasingly, humans have turned their attention to pre- serving the remaining flora and fauna. At the same time, even in cultures where the impetus to preserve diversity has been greatest, humans have been reluctant to sacrifice their prerogative to use lands for their exclusive benefit (Ehrenfeld 1972). Consequently, much research has been undertaken to determine the level and nature of human use that is compatible with retention of extant flora and fauna. This research has characteristically fit into a minimalistic approach to managing wildlife habi- tat; that is, how much can we do and still retain a diversity of species sufficient to satisfy our needs? For bears (Ursidae), this minimalistic approach is evident in harvest strategies, and park and wildlands management. Increasingly sophisticated management has entailed cumulative effects analysis (CEA) (Chris- tensen 1986); that is, how do bear populations respond to the interacting total of human activities on a given mean- ingfully scaled piece of ground, and does that fit into our management objectives? How bears respond to humans and their foods is critical input to the CEA and bear management in general. The most sensitive management requires input concerning differences in bear response among different sex and age classes, given that survivor- ship and productivity of adult females are apparently crit- ical to population viability (Knight and Eberhardt 1985, Yodzis and Kolenosky 1986, Ramsay and Stirling 1988). In this paper, I summarize and interpret how bear habitat use is affected by humans and their foods. I use ' Invited paper information pertaining mainly to brown (Ursus arctos) and American black (U. americanus) bears; where appli- cable I also include information on polar bears (U. maritimus) and Asian black bears (Selanarctos thibeta- nus). Humans affect bears many ways. Generally, bear response to humans and their alterations is a function of food biomass changes, bear tolerance of humans and human-related habitat changes, and human tolerance of bears. Where and how bears use their habitat is an integration of these factors. I use this framework to structure my presentation of results and interpretation.
The present distribution and abundance of the ursids is but an ephemeral reflection of an evolutionary path that began with the first identifiable bear, the dawn bear (Ursavus elmensis), 20 million years ago in the early Miocene epoch. Although the dawn bear was only the size of a fox terrier, by the Pleistocene its descendents had evolved into some of the largest terrestrial carnivores the world has known. Most bear species evolved in the northern hemisphere although some dispersed and reached South America, Africa and Southeast Asia. ing of the evolutionary pressures that the modem bears have evolved through may help us to understand their behavioral ecology. During the Pleistocene, bears at higher latitudes grew large and ecologically plastic while those closer to the equator remained small and became ecological specialists, as predicted by Geist's (1987) dispersal theory. Adaptations of the teeth of ancestral bear species allowed them to be both herbivores and carnivores. This allowed them to develop large size and broad ecological plasticity. Large body size enabled bears to conserve heat, capture large prey, defend carrion, travel great distances, and, as vegetation increased in the diet, to survive on qualitatively poorer food. Quantity and quality of available food and the degree of sexual dimorphism influenced the size of the home range and the evolution of social behavior in each species. Bears show a great deal of individual variation in behavior and may exploit different subniches as a result of learned behavior. Slight differences in phenotype may also influence exploitation of subniches. Recent literature indicates that some terrestrial bear species are more active predators than previously thought and some evidence suggests a degree of scaling between the size of bears and the size of their prey. Social signalling appears to have been influenced by life in forest habitats but is not well understood. We give a preliminary interpretation of the social organization of the present day bears through the interactive framework of proximate ecological pressures, phylogenetic history, and learning. There are likely few populations of bears anywhere in the world whose behavior has not been significantly influenced by man. This may confound our understanding of their behavior and ecology. Remaining populations of bears may not be able to adapt successfully to the combined effects of human predation, disappearing habitat, and climatic change.
A quantitative study of the behavior of brown bears (Ursus arctos) was undertaken at Brooks River in Katmai National Park and Preserve 1988-90 to determine whether human activity affected use of the area by females with young. Over the 3 fall seasons 862 hours of systematic observations were recorded or not (late Aug through mid-Oct salmon spawning period). Ten different females with young were observed, 4 of them over a complete reproductive cycle. Each female was classified according to human tolerance as "habituated" (n = 5), or "nonhabituated" (n = 5). The seasonal patterns of family group activity were examined according to habituation class. There was a direct relationship between the distribution of river use by nonhabituated family groups and proximity to Brooks Camp, while no relationship was found for habituated family groups. Use of areas by nonhabituated families increased near Brooks Camp late in the season, when human activity and noise in camp decreased. Availability of fish for bears was highest in areas near camp; however, nonhabituated females with young used these areas significantly less than habituated families.
The statistical literature on tests to compare treatments after the anlysis of variance is reviewed. Monte Carlo simulations on normal and lognormal data indicate that many of the tests commonly used are inappropriate or inefficient. Particular tests are recommended for unplanned multiple comparisons on the basis of controlling experimentwise type I error rate and providing maximum power. These include tests for parametric and nonparametric cases, equal and unequal sample sizes, homogeneous and heterogeneous variances, non-independent means (repeated measures or adjusted means), and comparing treatments to a control. Formulae and a worked example are provided. The problem of violations of assumptions, especially variance heterogeneity, was investigated using simulations, and particular strategies are recommended. The advantages and use of planned comparisons in ecology are discussed, and the philosophy of hypothesis testing with unplanned multiple comparisons is considered in relation to confidence intervals and statistical estimation. -Authors
Reports of grizzly bear (Ursus arctos) observations between 1977 and 1979 in Glacier National Park were examined to test whether the behavior of grizzly bears was different in areas with high versus low levels of human activity. In both types of areas, females with young were more likely than adults and subadults to avoid human-use areas and showed little habituation to people. A midseason increase in habituated behavior by adult and subadult bears occurred in both areas, but adults and subadults showed a greater degree of habituation throughout the season in the high-use area.
Brown bear (Ursus arctos middendorffi) movements and seasonal range were examined in relation to the temporal and spatial distribution of salmon (Oncorhynchus spp.) on southwest Kodiak Island, Alaska, from 1983 to 1987. Salmon were available to bears from late June to mid-December and were utilized by all sex and age classes. From 50-89% of adult females fished at ≥2 separate areas of salmon abundance each year. Mean composite summer range of females tracked 2-5 yrs (108 km2) was much greater than either spring (13 km2) or fall (26 km2) range. Annual summer range of 8 females tracked 4 consecutive years averaged 40 km2; a smaller mean area of primary use (12 km2) reflected a pattern of movement between areas of concentrated food. Females did not restrict their movement patterns in years they were accompanied by new (<1 yr) cubs. Males fished for salmon at the same sites used by females but traveled between those areas more often than females. Annual variation in movement patterns was due apparently to behavioral differences among individual bears as well as yearly fluctuations in berry production, salmon availability, and unknown factors. Important bear feeding areas in this region can be conserved by monitoring salmon escapements together with associated bear use, and by restricting human access at particular sites.
Although improved management has reduced the number of more serious incidents between Ursus arctos horribilis and people in Denali, the rate of interactions has increased from 80 per million visitors in 1987 to 197 per million visitors in 1989. Most interactions in frontcountry areas occurred in early June and late August, and probably involved bears habituated to humans. Backcountry interactions were strongly correlated with the number of people riding shuttle buses and may have been caused by less-habituated bears moving from frontcountry to backcountry areas, or from seasonal changes in habitat selection by bears. -from Authors
Grizzly bears (Ursus arctos) and black bears (U. americanus) prey on spawning cutthroat trout (Oncorhynchus clarki, formerly known as Salmo clarki) in tributary streams of Yellowstone Lake. These tributary streams were surveyed from 1985 to 1987 to determine the presence and level of trout spawning activity and bear use. Indices were developed to enumerate spawner density and levels of bear use. Of 124 known tributaries of Yellowstone Lake, 48% had a spawning run. Of these spawning streams, 93% had associated bear activity, and 61% had associated evidence of bear fishing. Bears were apparently using more spawning streams and fish compared to 10 years earlier. Bear use of cutthroat trout spawning streams appeared to be largely a positive function of volumetric spawner density. We hypothesize that abundance and quality of stream-side vegetation relative to other foraging options influenced bear use. Intra- and interspecific avoidance among bears was suggested by patterns of spawning stream use. Less bear use of spawning streams than expected occurred within 1 km of park developments.
Human disturbance of brown bears (Ursus arctos) was studied in the Pack Creek area of Admiralty Island in Southeast Alaska during the summers of 1983 and 1984. The Pack Creek watershed has been closed to bear hunting since 1934, but use of the area by bear watchers and photographers is increasing. Instantaneous scan sampling and focal animal sampling techniques were used to observe bears and visitors at a control area with negligible human activity and at the popular Pack Creek area. Analysis of diel use of the 2 areas showed a crepuscular pattern for both the control and Pack Creek bears. Bears that are conditioned to human food or highly habituated to visitors tended to use the Pack Creek area during the midday periods of high visitor use more than other bears. Over 80% of the observations of Pack Creek bears were of female bears, suggesting that visitor use may differentially affect sexes. Bears that associated people with food showed levels of boldness that could lead to undesirable incidents. Int. Conf. Bear Res. and Manage. 7:377-382 The effect of human population growth and activ- ities on brown or grizzly bears is obvious from the drastic decline in their numbers and range. Although direct impacts such as uncontrolled hunting and hab- itat loss are often the problem, more subtle distur- bances can also play a role. In parks and refuges where wildlife is afforded a high degree of protection, human activities such as camping, hiking, and pho- tography can be stressful to bears. This stress may cause bears to make temporal or spatial adjustments in their activity patterns, become more aggressive, develop secretive habits, and develop physiological problems such as illness and reduced reproduction (McArthur 1979). Frequent human contact also can cause bears to become habituated to people. Opinions differ on the effects of habituation. McCullough (1982) believes habituated bears may be more dangerous to people than nonhabituated bears because there is a greater likelihood of close encounters. In contrast, Jope (1985) suggests that aggression toward humans may diminish when bears become accustomed to their presence, suggesting that habituated bears pose less of a threat to humans. The most dangerous situation appears to be when habituated bears associate people with food sources such as improperly stored foods, garbage, and edible handouts (Herrero 1985:51). When dangerous situations develop, the lives of the bears involved are also threatened; this is especially true in areas where firearms are allowed (Follmann et al. 1980). This study was designed to assess the impacts of people on brown bears in an area where hunting is prohibited and where activities such as bear viewing and photography are gaining in popularity. Funding was provided through the Alaska Coop. Wildl. Res. Unit by the Alaska Dep. of Fish and Game from a special appropriation of the Alaska State Legislature. Support was also given by Admiralty Island National Monument. Special thanks are due to J. Schoen, V. Beier, D. McKnight, H. Clough, E. Follmann, R. Tabbert, F. Dean, R. Johnson, D. Larsen, and K. Post.
Seven major types of sampling for observational studies of social behavior have been found in the literature. These methods differ considerably in their suitability for providing unbiased data of various kinds. Below is a summary of the major recommended uses of each technique: In this paper, I have tried to point out the major strengths and weaknesses of each sampling method. Some methods are intrinsically biased with respect to many variables, others to fewer. In choosing a sampling method the main question is whether the procedure results in a biased sample of the variables under study. A method can produce a biased sample directly, as a result of intrinsic bias with respect to a study variable, or secondarily due to some degree of dependence (correlation) between the study variable and a directly-biased variable. In order to choose a sampling technique, the observer needs to consider carefully the characteristics of behavior and social interactions that are relevant to the study population and the research questions at hand. In most studies one will not have adequate empirical knowledge of the dependencies between relevant variables. Under the circumstances, the observer should avoid intrinsic biases to whatever extent possible, in particular those that direcly affect the variables under study. Finally, it will often be possible to use more than one sampling method in a study. Such samples can be taken successively or, under favorable conditions, even concurrently. For example, we have found it possible to take Instantaneous Samples of the identities and distances of nearest neighbors of a focal individual at five or ten minute intervals during Focal-Animal (behavior) Samples on that individual. Often during Focal-Animal Sampling one can also record All Occurrences of Some Behaviors, for the whole social group, for categories of conspicuous behavior, such as predation, intergroup contact, drinking, and so on. The extent to which concurrent multiple sampling is feasible will depend very much on the behavior categories and rate of occurrence, the observational conditions, etc. Where feasible, such multiple sampling can greatly aid in the efficient use of research time.
Thesis (Ph. D.)--Utah State University, 1978. Includes bibliographical references (leaves 112-115). Microfilm. s
Thesis (M.S.)--Utah State University. Dept. of Fisheries and Wildlife, 1993. Includes bibliographical references.
Learning and instinct in animals. Har-vard University Press Distributions and densities of brown bear on various streams in Katmai National Monument
- W H Thorpe
- Ma Troyer
Thorpe, W. H. (1956) Learning and instinct in animals. Har-vard University Press, Cambridge, MA. Troyer, W. (1980) Distributions and densities of brown bear on various streams in Katmai National Monument. U. S. National Park Service, Alaska Regional Office, Anchorage (unpublished report).
Factors related to bear-human interactions in Denali National Park Alaska Department of Fish and Game Division of Commer-cial Fisheries (1993) Annual Management Reports
- D M Albert
- R T Bowyer
Albert, D. M. and Bowyer, R. T. (1991) Factors related to bear-human interactions in Denali National Park. Wildl. Soc. Bull. 19, 339-349. Alaska Department of Fish and Game Division of Commer-cial Fisheries (1993) Annual Management Reports, 1992, Bristol Bay Area. Regional information report, No. 2A93-32.
Habitats, trails, and campground situations associated with grizzly-human confrontations in Glacier National Park, Montana
- Nadeau
Nadeau, S. M. (1987) Habitats, trails, and campground situa-tions associated with grizzly-human confrontations in Gla-cier National Park, Montana. MSc thesis, University of Montana, Missoula.
The social behavior of brown bears at McNeil River, Alaska Visitor impact on grizzly bear activity in the Pelican Valley
- A L Egbert
- K A Gunther
Egbert, A. L. (1978) The social behavior of brown bears at McNeil River, Alaska. PhD thesis, Utah State University, Logan. Gunther, K. A. (1990) Visitor impact on grizzly bear activity in the Pelican Valley, Yellowstone National Park. Int. Conf Bear Res. & Manage. 8, 73-78.
Visitor impact on brown bears at Pack Creek, Admiralty Island, Alaska Biostatistical analysis
- S H Warner
Warner, S. H. (1987) Visitor impact on brown bears at Pack Creek, Admiralty Island, Alaska. MSc thesis, University of Alaska, Fairbanks. Zar, J. H. (1984) Biostatistical analysis, 2nd edn. Prentice Hall, Englewood Cliffs, NJ.
Adaptation of brown bears to people on an Alaskan stream: a quantitative study
- Braaten
Braaten, A. M. (1988) Adaptation of brown bears to people on an Alaskan stream: a quantitative study. MSc thesis, Utah State University, Logan.
Nonsport grizzly bear deaths in Alaska. lnt. Conf
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- M A Chihuly
Miller, S. D. and Chihuly, M. A. (1987)Nonsport grizzly bear deaths in Alaska. lnt. Conf. Bear Res. & Manage. 7, 51-58.
Nonsport grizzly bear deaths in Alaska
- Miller
Variable impacts of people on habitat use, movements, and activity of brown bears on an Alaskan river
- Olson
Annual Management Reports, 1992, Bristol Bay Area
- Alaska Department of Fish and Game Division of Commercial Fisheries