Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
In North Carolina, winter weather events causing sea surface temperatures to acutely drop below approximately 12°C may result in strandings of threatened loggerhead Caretta caretta, green Chelonia mydas and endangered Kemp's ridley Lepidochelys kempii sea turtles due to cold stun syndrome. Clinically, these turtles have been shown to have metabolic and respiratory acidosis. The purpose of this study was to apply NMR-based metabolomics to further our understanding of the pathogenesis of cold stun syndrome in sea turtles. Heparinized whole blood and plasma samples were collected from apparently healthy loggerhead (whole blood n = 8), green (whole blood n = 12, plasma n = 10) and Kemp's ridley (whole blood n = 14, plasma n = 10) sea turtles. Blood and plasma samples were also collected from juvenile, in-water or beach-cast cold stun affected sea turtles (loggerhead n = 9, green n = 11, Kemp's n = 6). We identified 18 metabolites in our spectra including amino acids, energy compounds, glycerol, ketone bodies, nucleosides/nucleotides, organic acids and osmolytes. There were several significant differences between metabolites in control and affected turtles, likely secondary to anorexia, such as differences in dimethyl sulfone, glycerol, leucine, isoleucine and trimethylamine N-oxide concentrations. Significant differences in multiple metabolites related to exertion and anaerobic metabolism included concentrations of acetate, creatine, lactate and succinate. Changes in glycerol and propylene glycol concentrations suggest some metabolic changes may have cold protective properties. The primary metabolomic findings were consistent with what is known about clinical biochemistry and blood gas panel perturbations in cold stun affected turtles. This study provides a baseline for the metabolic profile of control and cold stun affected sea turtles in North Carolina and we have identified several metabolites worthy of further investigation with regards to their roles in hypoxia, ischemia and reperfusion.
While the harvest success rate of bull elk in Nebraska has been relatively high in recent years, antlerless harvest success is substantially lower inhibiting the ability of wildlife managers to effectively manage population numbers. We sought to explore differences in hunter behaviour based on the type of elk being hunted as well as how specific constraints affected each type of hunter's ability to hunt and harvest elk. Decreased antlerless-elk harvest rates were likely a product of the reduced frequency in which an antlerless-elk hunter would pay for the opportunity to hunt on property containing a comparatively higher probability of harvest. Antlerless-elk hunters reported being more constrained by time, and felt more strongly that the quantity of elk on the land that they hunted affected their ability to harvest. Our results reinforce the need for wildlife managers to work closely with private landowners and focus hunting pressure on land currently restricted to elk hunting.
We compiled, summarized and reviewed 338 cases of people killed or injured by brown bears from 1932 to 2017 in Russia, home of about half of the world's brown bears. During the Soviet period, 1932–1990, hunters and outdoor workers were injured/killed by bears more frequently than people engaged in other activities, 28% and 19% among all incidents, respectively. However, after 1991, people who gathered wild resources, hiked or were within human settlements were most affected (22, 16 and 15%, respectively). Single bears were involved in most of the incidents before and after 1991 (76% and 74% of the cases, respectively). In 1991–2017, the post-Soviet period, when data availability was better, bear-caused injuries and fatalities (264 records) occurred more often on the Russian Pacific Coast (111 incidents) and in Siberia (109 incidents) than in European Russia (44 incidents), where human encroachment in bear habitat is higher. During the same period, the percentages of fatalities were not significantly different among the areas; 39% in European Russia, 49% in Siberia and 50% on the Pacific Coast. Casualties occurred mainly during daytime and especially in summer and autumn. In 182 incidents with known probable causes, bears most frequently attacked when provoked or disturbed (38%) and surprised (21%), but 18% of the incidents seemed to reflect bear predatory behavior. Hence, we encourage researchers and wildlife managers to develop educational programs on large carnivore biology and behavior and to better manage human activities in bear country in order to minimize human–bear conflicts in Russia and elsewhere.
A home range represents the outcome of the interplay between an environment, an animal's understanding of that environment, and its subsequent movement decisions. Yet, recent studies suggest that recursive movement strategies have been overlooked in the shaping of animal home range patterns. Using fourteen GPS collared red foxes, we investigated within home range movements for recursive movement behaviour, suggesting a cognitive map, and explored how these shape animal space-use patterns. We found that red foxes showed significant clustering in recorded positions, indicative of recursive site use. An average of 43% of positions were found in defined clusters that covered a proportional area of only 1% of their recorded range. Ground-truthing revealed that clusters were attributed to recursive visits, and extended residence time at clumped food sources, bed or den sites, routes and vantage points in the landscape. Our results provide evidence that, while red foxes maintained exploratory movement, recursive site use played a significant role in optimising movements between distinct core areas. We conclude that these patterns support the concept of cognitive mapping enabling recursive resource use, which can lead to emergence of bounded space use, rather than a continuous drifting across the landscape. We propose that by identifying resource locations that are used recursively; it is possible to move a step closer in revealing an animal's cognitive map, or indeed, the movement behaviour underlying home range formation.
Vaccination strategies provide a crucial tool for managements of disease risks in wildlife, but have been utilized mostly for domestic species. However, a significant body of work has now been published describing the successful development of an anti-chlamydial vaccine for the koala Phascolarctos cinereus, Goldfuss, 1817. As such, vaccinations against these infections in the koala, can provide important insights into the use of vaccines for wildlife. Chlamydia infections in the koala have been intensively studied for over 30 years. Infections cause severe disease states, such as kerato-conjunctivitis (blindness) and reproductive tract disease (infertility), and/or mortality; and are contributing significantly to population declines. We aim to use the plethora of data available from koala chlamydial studies as a template to propose a roadmap for the development of vaccines for other wildlife species, especially in this era of antibiotic resistance. As such we have outlined the important steps that have led to significant milestones resulting in the successful development of a vaccine against an infectious disease in a non-domestic species. We hope to thus provide, not only a timely review on Chlamydia vaccines in koalas, but also an important conservation and management roadmap to help guide future researchers that are considering the development of a vaccine for a wild species.
Human–wildlife conflict arising from livestock-losses to large carnivores is an important challenge faced by conservation. Theory of prey–predator interactions suggests that revival of wild prey populations can reduce predator's dependence on livestock in multiple-use landscapes. We explore whether 10-years of conservation efforts to revive wild prey could reduce snow leopard's Panthera uncia consumption of livestock in the coupled human-and-natural Trans-Himalayan ecosystem of northern India. Starting in 2001, concerted conservation efforts at one site (intervention) attempted recovery of wild-prey populations by creating livestock-free reserves, accompanied with other incentives (e.g. insurance, vigilant herding). Another site, 50km away, was monitored as status quo without any interventions. Prey remains in snow leopard scats were examined periodically at five-year intervals between 2002 and 2012 to determine any temporal shift in diet at both sites to evaluate the effectiveness of conservation interventions. Consumption of livestock increased at the status quo site, while it decreased at the intervention-site. At the intervention-site, livestock-consumption reduced during 2002–2007 (by 17%, p=0.06); this effect was sustained during the next five-year interval, and it was accompanied by a persistent increase in wild prey populations. Here we also noted increased predator populations, likely due to immigration into the study area. Despite the increase in the predator population, there was no increase in livestock-consumption. In contrast, under status quo, dependence on livestock increased during both five-year intervals (by 7%, p=0.08, and by 16%, p=0.01, respectively). These contrasts between the trajectories of the two sites suggest that livestock-loss can potentially be reduced through the revival of wild prey. Further, accommodating counter-factual scenarios may be an important step to infer whether conservation efforts achieve their targets, or not.
Human–wildlife impacts (HWI) occur due to interactions between wildlife and human activities in our increasingly anthropogenic world and typically result in economic losses or increased health- and safety risks. HWI can be especially prevalent where urbanization encroaches upon natural areas, or in fragmented human-dominated landscapes. An example of such situation is the re-occurrence of wild boar in Flanders (northern Belgium). Flanders is one of the most densely populated areas of Europe and is characterized by a severely fragmented landscape. The recent return of wild boar to Flanders challenges managers to find solutions for a sustainable co-existence between humans and wild boar. As crop damage is increasing and targeting preventive measures efficient requires identifying high risk areas, we assessed the influence of the landscape around a field, as well as field-specific characteristics on the likelihood of wild boar crop damage. Because most of the reported damage in Flanders occurs in grasslands (cultivated to produce hay) and maize fields, we focused on these. We used boosted regression trees and the brglm-technique to construct distribution models explaining spatial patterns of crop damage. We found that for maize fields, landscape-level variables such as the proportion of maize, grassland, forest and urbanized areas in the surroundings of the field are key factors determining the probability of damage. In contrast, field-specific variables only played a minor role. For grasslands, both field-specific and landscape characteristics affected damage probability: a higher probability of damage was associated with decreasing distance to nearest forest, increasing distance to the nearest road, the use of inorganic fertilization and increasing age of the grassland. Our results suggest that the risk of crop damage by wild boar can potentially be mitigated by changes in agricultural practices that alter grassland characteristics, and by targeting preventive measures towards high risk maize in well-defined locations.
Estimating the survival of juveniles is important to the study of ecology and wildlife management. Methods to estimate survival from uniquely marked young are generally preferred but may be difficult to implement. Alternative methods to estimate juvenile survival based on counts of unmarked young with marked parents generally do not account for detection probability or encounter difficulty estimating survival when there are >5 offspring. We developed a hierarchical Bayesian model to estimate survival of unmarked offspring from known (marked) parents from a minimum of two counts on while accounting for imperfect detection. We simulated data to evaluate the performance of the model across a range of detection probabilities and sample sizes and to explore violations of some model assumptions. We then demonstrate the utility of this approach by estimating chick survival for a population of ring-necked pheasants Phasianus colchicus in east-central Illinois, USA. Mean error of parameter estimates decreased with increasing sample sizes and detection probability and was greater for covariate coefficients, compared to mean detection or survival probabilities. However, posterior distributions of mean survival and detection parameters were poorly estimated and had small effective sample sizes when the mean detection probability was ≤0.4 or the number of broods comprising the sample were <30. The model was relatively robust to violations of the model's closure assumption, with a <0.04 increase in bias of detection and survival probabilities when survival between repeated counts was <1. When applied to our data set of 38 pheasant broods, we were able to identify important temporal and environmental covariates affecting survival and detection. Mean detection probability was only 0.56. We believe the coupling of this model with an appropriate field sampling framework provides a useful and flexible approach that is time- and cost-efficient for estimating survival of unmarked young.
Forestry practices can lead to changes in wildlife habitat that could have lasting effects on the distribution of species. Hence, the aim of this study was to determine the effects of forestry practices on habitat variables and habitat use by mammals in three different stands (control, clear-cut and clear-cut with reserves) in a Japanese larch Larix kaempferi plantation from April to October in 2016 and 2017. We recorded the presence of field signs for the following six mammal species: Korean hare Lepus coreanus, raccoon dog Nyctereutes procyonoides, Eurasian badger Meles meles, water deer Hydropotes inermis, roe deer Capreolus pygargus and wild boar Sus scrofa. Habitat variables significantly differed among three stands. Field sign (feces, foot prints and feeding signs) abundances of mammals showed significant differences between the control and clear-cut stands. Moreover, field sign abundances of all species were highest in the clear-cut with reserves stand. We calculated the impact of clear-cutting on habitat use by mammals using GLMMs. Both clear-cutting in the models were significant and had positive coefficients on habitat use by Korean hare, raccoon dog, deer and wild boar. In Eurasian badger models, only clear-cutting with reserves show positive impacts on habitat use. Habitat selection by forest edge species such as Korean hare and deer showed dependence on understory structure. Abundant understory in the clear-cut with reserves stand may not only provide vegetative food and cover for herbivores but also small prey species for omnivores and carnivores. The results of our study show that forest understory is one of the most instrumental factors mitigating the effects of clear-cutting on habitat use by mammal and it should, therefore, be given due importance in forestry practices.
Effective wildlife management requires a broad understanding of how forest structure and composition influence habitat use and vital rates during all aspects of species' life-cycles, however habitat characteristics may have variable importance during different life phases. Even though the ruffed grouse Bonasa umbellus is a popular game bird that has long been a focal species for management, a greater understanding of the links between forest characteristics and components of ruffed grouse reproduction would enhance managers' ability to promote the species. We monitored 45 nests belonging to 37 females during 2015–2017 in central Maine, USA, and evaluated the influence of forest characteristics on nest-site selection, nest survival and female survival while nesting. Ruffed grouse females selected nest sites with greater horizontal visual obstruction (β = 0.16 ± 0.06 85% CI) than found at other sites that were locally available to them, however this characteristic did not appear to improve nest survival or female survival while nesting. Cumulative nest success was 42.8% and daily nest survival was reduced when coarse woody debris (CWD) was present at nest sites (β = –0.41 ± 0.33 85% CI), but we found no evidence that other habitat characteristics or features of nests themselves were related to nest survival. However, reduced female survival while nesting was associated with presence of CWD (β = –1.27 ± 0.91 85% CI), greater tree basal area (β = –0.96 ± 0.81 85% CI) and greater conifer stem density (β = –0.45 ± 0.28 85% CI) at nest sites; females had a 74.4% chance of survival during the length of time required to successfully nest. Our results demonstrate the importance of forest characteristics on multiple components of species' nesting ecology, and we provided management suggestions to promote attractive ruffed grouse nesting habitat while potentially mitigating sources of nesting failure.
Fishponds constitute a major breeding habitat for the common pochard Aythya ferina in Europe. This study explored possible causes of its recent decline, in describing the consequences of diverse pond management options in Brenne, central France. Pair density and the brood:pair ratio were described in a pond sample under varying management practices, in the early 2000s and, again, a decade later. The influence of pond management on these variables was studied by model comparisons. In the early 2000s, 69.5% of the studied ponds were fertilized by fish farmers. Higher pochard pair densities were observed in those with artificial carp feeding and the brood:pair ratio was positively related to fish biomass density, provided that pair density was not too high. A decade later, only 25% of studied ponds remained fertilized. Pochard pair density was positively correlated with fish biomass density. But lower brood:pair ratios were recorded in ponds with artificial carp feeding, due to the fact that higher pair density there did not lead to increased brood density. Between the two study periods, the pair number remained stable in the sample but the brood:pair ratio decreased, from 0.84 to 0.71. Our results support the idea that habitat conditions that enable high fish productivity were also attractive for pochard pairs. They suggest the hypothesis that pond fertilization for enhancing primary productivity and, thereby, fish biomass, may also favour pochard breeding success. We must however bear in mind that, even with active fish farming management, fish biomass density in French fishponds remains usually moderate when compared to those in central Europe. The study did not reveal any effect of hunting management since waterfowl feeding, predator control or mallard release did not significantly influence either pond use by pochard pairs or the brood:pair ratio.
What kind of tree should be preserved from logging for biodiversity conservation is a matter of debate. Large and old trees are potential candidates due to the structures they can bear, like cavities and other tree-related microhabitats (TreMs). One of the most studied TreM is woodpecker-made cavities, which, in addition to be breeding sites for primary cavity-nesters, are often the main breeding sites for secondary cavity-nesters, especially in managed forests. Therefore, understanding which trees woodpeckers select for cavities is relevant to forest management, especially in management regimes where individual trees are logged or spared, as in retention forestry. We used data from a forest inventory, TreM inventory and woodpecker counts in one-hectare plots in the Black Forest (southwest Germany) to investigate which features make a retention tree suitable for woodpeckers. By employing a resource selection probability function, we tested several variables for their influence on the probability of tree choice by woodpeckers including altitude, tree species, TreM richness and abundance, diameter at breast height (DBH) and deviation from the mean DBH per plot. The results show that the probability of selection by woodpeckers does not correlate with individual tree diameter. Instead, the probability is driven mainly by the deviation from the mean DBH per plot. We were able to identify a relative size for the selection of trees indicating that woodpeckers prefer trees that are about 15–20 cm larger than the mean DBH per plot. Thereby, we argue, that using absolute diameter thresholds to select retention might not be the best management solution in the short-term, as in managed forests woodpeckers might select sub-optimal trees. Apparently, more knowledge concerning relative thresholds, as detected in our study, is required to improve our understanding of the potential ecological value of retention trees.
Wild ungulates have expanded their geographical range across Europe and Portugal is no exception. Despite the known benefits associated with the increase of these populations (e.g. increased prey for wild carnivores), the negative impacts also need to be taken into account (e.g. damages in agriculture and forestry, ungulate–vehicle collisions). Additionally, their role as reservoirs of zoonotic agents has gained scientific relevance due to the potential human health risks, impact on livestock and food safety. In northeast Portugal, Montesinho Natural Park, three species of ungulates occur in sympatry, the wild boar Sus scrofa, the red deer Cervus elaphus and the roe deer Capreolus capreolus. Considering their close association with humans and livestock, it is essential to understand their role as reservoirs of infectious diseases, namely as vectors for parasitic infections. In order to achieve this, 112 fresh faecal samples were collected to assess, by means of coprological analyses, their parasite diversity, prevalence and mean intensity. In total, 88 (78.60%, ±69.81–85.76) samples were infected with at least one parasite species. Parasite prevalence was different among the three species, with the red deer showing higher prevalence values (83.6%), then the wild boar (80.2%) and the roe deer (46.7%). The results have revealed that these species carry parasites that not only represent a health problem for domestic ruminants and domestic pigs (e.g. Muellerius sp., Trichostrongylidae, Strongylidae, Metastrongylus sp., Moniezia benedeni, Eimeria spp. and Cystoisospora sp.) but they can also pose a potential public health risk (e.g. Balantidium coli). The implementation of surveillance programs must include regular monitoring protocols of wild ungulates.
Habitat fragmentation represents the single greatest conservation challenge of the 21st century. This problem is particularly acute for large, obligate carnivores like pumas Puma concolor which have persisted in North and South America in the face of habitat fragmentation and other anthropogenic disturbances. Shrinking habitat and reduced connectivity mean that mapping habitat is increasingly important for species conservation in multiple-use landscapes. Previous work suggests that pumas occupy habitats where sufficient stalking cover and preferred prey are present, yet the intersection of these factors has rarely been assessed. Here we used data from 68 299 camera trap nights collected from 181 sites throughout the San Francisco Bay Area over a four-year period to identify key predictors of habitat occupancy for pumas and their primary prey (mule deer Odocoileus hemionus). Our goal was to determine whether pumas occupy habitats based on relative measures of prey availability (detection frequency), or ease of predation (density of stalking cover) and whether these predictors changed between seasons. Our results indicated that pumas primarily occupied forested habitats and did not choose habitats with abundant deer. Instead, pumas preferentially occupy habitats that facilitate their stalk and ambush hunting strategy, rather than higher prey densities, per se. The best occupancy models for mule deer indicated the importance of roads and shrub cover. However, even the best deer models performed poorly compared to the puma models, likely due to the ubiquity of mule deer in the region. Although prey density is a widely accepted correlate of habitat quality for many carnivores, our results suggest that structural elements of habitat may be a more important variable in predicting habitat use by large stalk and ambush predators like pumas, which has important implications for conservation success.
Many models in population ecology, including spatial capture–recapture (SCR) models, assume that individuals are distributed and detected independently of one another. In reality, this is rarely the case – both antagonistic and gregarious relationships lead to non-independent spatial configurations, with territorial exclusion at one end of the spectrum and group-living at the other. Previous simulation studies suggest that grouping has limited impact on the outcome of SCR analyses. However, group associations entail not only spatial clustering of activity centers but also coordinated space use by group members, potentially impacting both ecological and observation processes underlying SCR analysis. We simulated SCR scenarios with different strengths of aggregation (clustering of individuals into groups with shared activity centers) and cohesion (synchronization of detection patterns of members of a group). We then fit SCR models to the simulated data sets and evaluated the effect of aggregation and cohesion on parameter estimates. Low to moderate aggregation and cohesion did not impact the bias and precision of estimates of density and the scale parameter of the detection function. However, non-independence between individuals led to high levels of overdispersion. Overdispersion strongly decreased the coverage of confidence intervals around parameter estimates, thereby increasing the probability of erroneous predictions. Our results indicate that SCR models are robust to moderate levels of aggregation and cohesion. Nonetheless, spatial dependence between individuals can lead to false inference. We recommend that practitioners 1) test for the presence of overdispersion in SCR data caused by aggregation and cohesion, and, if necessary, 2) correct their variance estimates using the overdispersion factor ĉ . Approaches for doing both are described in this paper. We also urge the development of SCR models that incorporate spatial associations between individuals not only to account for overdispersion but also to obtain quantitative information about social aspects of study populations.
There are few stressful factors which have been investigated to affect adrenocortical function in the African wild dog (AWD) Lycaon pictus. Understanding what animals perceive as stressors is important for not only the implementation of management practices promoting general animal welfare in captivity, but also because a prolonged stress perception is known to disrupt reproduction, immune function and ultimately pose a threat to survival. In this regard, faecal glucocorticoid metabolite (fGCM) measurements are commonly used as a non-invasive approach to assess the impact of factors which may be acting as perceived stressors in wildlife. This study was aimed at determining if there are significant differences in AWD fGCM concentrations as a result of sex, presence of absence of an injury, age-class, body condition, dietary provisioning (through stable nitrogen (δ15N) and carbon (δ13C) isotope analysis), hierarchal status, and setting (i.e. captive or free-ranging). A total of 47 faecal samples were collected immediately post-defaecation from 39 AWDs across four free-ranging sites (Hluhluwe-iMfolozi Park, Madikwe Game Reserve, Kruger National Park and the Waterberg), two permanently captive sites (Johannesburg and Pretoria Zoo), and four temporary captive holding facilities (Hoedspruit Endangered Species Centre and Maremani, Tembe and Zimanga bomas) in South Africa. Captive AWDs had distinctively higher fGCM levels than their free-ranging counterparts, regardless of sex, body condition, hierarchal status, age-class or dietary provisioning. The present study is the first to assess physiological stress responses across permanently captive, temporarily captive and free-ranging AWDs within the South African managed metapopulation, while incorporating the use of stable isotope analysis to quantify differences in dietary isotopic profiles between these different settings. Ultimately this demonstrates the usefulness of fGCM analysis as a tool for assessing animal welfare in both captive and free-ranging AWDs, and underpins the importance of understanding factors perceived as stressors for the management of the species. Keywords: animal welfare, body condition scoring, faecal glucocorticoid metabolite monitoring, managed metapopulation, stress, wildlife management.
Wild boar space use and the determinants of its variation are crucial information for understanding wild boar Sus scrofa (L.) ecology and for wild boar management. Wild boar space use has mostly been investigated on broad temporal scales such as annual or seasonal home ranges. Ranges can vary depending on the observed timespan and on the temporal scales considered. The factors that affect space use variation can also depend on temporal scales.
In this study, we present an analysis of time series of daily ranging behaviour in wild boar. Using GPS-telemetry, we tracked 46 collared wild boars in southwest Germany. With the collected data, we calculated 6716 daily ranges of individuals based on at least 18 daily locations with near hourly location intervals. We compared three home range estimation methods and fitted multivariate models to assess the effects of the landscape, temporal and climatic factors or individual traits on the daily range size.
The daily range size varied significantly in the course of the year. The smallest daily ranges were covered from April to July, whereas the largest were covered in November and December. However, if the same days of the year are compared, lower temperatures reduced the size of daily ranges. Additionally, individual variation, social class, snow height, land use and elevation had a significant effect on the size of daily ranges.
Our results may be useful for planning protected areas, for monitoring wild boar populations, attributing agricultural damages to wild boar groups and for searching wounded or escaped animals. Moreover, the knowledge of daily used space may help to identify African swine fever (ASF) infection paths or design measures to reduce ASF risk including carcass removal, fencing projects or demarcation of management zones.
Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive sampling of a certain number of individual animals. Marking and sampling practices include taking blood and tissue samples, toe-clipping of amphibians and rodents, or using implants and radio-transmitters – techniques that can negatively affect the animal. Wildlife research may then result in a fundamental conflict between individual animal welfare and the welfare of the population or ecosystem, which could be significantly reduced if non-invasive research practices were more broadly implemented. Implementation of non-invasive methods could be guided by the so-called 3Rs principles for animal research (replace, reduce, refine), which were proposed by Russell and Burch 60 years ago and have become a part of many animal protection legislations worldwide. However, the process of incorporating the 3Rs principles into wildlife research has been unfortunately rather slow and their importance overlooked. In order to help alleviate this situation, here I provide an overview of the most common practices in wildlife research, discuss their potential impact on animal welfare, and present available non-invasive alternatives.
Weather appears to influence collisions of migratory birds with human-built structures including buildings, but formal analyses are lacking. In 2018, as part of a two-year study at 21 buildings in Minneapolis, Minnesota, USA, we observed a large number of American woodcock Scolopax minor collisions during two early spring snowstorms. We describe these events, analyze associations between weather and woodcock collisions during spring 2018, and compare observations to past studies across the woodcock's range. Most spring 2018 woodcock collisions (11 of 15; 73.3%) occurred in association with the two snowstorms. Analyses indicated collisions were positively associated with maximum and average wind speeds the night before collision surveys, and most collisions occurred with north winds. Collisions also increased with lower cloud base height two nights before surveys. These results support that woodcock collisions were greatly influenced by inclement weather, specifically the coincidence of strong north wind and low clouds. Comparing results to past studies illustrates that building collisions could be a major range-wide source of woodcock mortality, especially in spring migration when mortality is likely additive. Although more research is needed to understand range-wide, population-level effects of woodcock collisions, management to reduce building collisions during migration may benefit woodcock populations. Additional research is needed to clarify effects of weather on bird collisions because management efforts could be refined if collisions of woodcocks and other bird species were forecastable like the weather.
Studies of the movements and abundance of predators can reveal their ecological roles and facilitate their conservation. These studies rely increasingly on noninvasive methods such as hair collection and camera traps. Insights from hair sampling, however, may be compromised if collection devices elicit avoidance behavior. To determine the extent to which brown bears Ursus arctos avoided barbed wire deployed to collect hair samples, we paired two wires on each of six small streams with motion-activated video recorders in the Wood River system, southwestern Alaska, where bears prey on sockeye salmon Oncorhynchus nerka. Of 350 videos showing a bear approaching the wire with an unambiguous result, the bear contacted the wire in 80.9% and avoided it 19.1% of the approaches. Females more often avoided the wire than did males (39% versus 20%), and bears more frequently avoided the wire at night (23.6%) than during daytime (10.8%) and crepuscular (19.1%) periods. Other comparisons (bears in groups versus single bears, and adults versus cubs) were not significantly different. The high proportion of approaches that led to contact with the wire indicates that this hair-sampling method is generally successful. Our findings also suggest, however, that interpretation of data obtained from such sampling should consider the possibility of biases with respect to sex and time of day.
There are few stressful factors which have been investigated to affect adrenocortical function in the African wild dog (AWD) Lycaon pictus. Understanding what animals perceive as stressors is important for not only the implementation of management practices promoting general animal welfare in captivity, but also because a prolonged stress perception is known to disrupt reproduction, immune function and ultimately pose a threat to survival. In this regard, faecal glucocorticoid metabolite (fGCM) measurements are commonly used as a non-invasive approach to assess the impact of factors which may be acting as perceived stressors in wildlife. This study was aimed at determining if there are significant differences in AWD fGCM concentrations as a result of sex, presence of absence of an injury, age-class, body condition, dietary provisioning (through stable nitrogen (δ15N) and carbon (δ13C) isotope analysis), hierarchal status, and setting (i.e. captive or free-ranging). A total of 47 faecal samples were collected immediately post-defaecation from 39 AWDs across four free-ranging sites (Hluhluwe-iMfolozi Park, Madikwe Game Reserve, Kruger National Park and the Waterberg), two permanently captive sites (Johannesburg and Pretoria Zoo), and four temporary captive holding facilities (Hoedspruit Endangered Species Centre and Maremani, Tembe and Zimanga bomas) in South Africa. Captive AWDs had distinctively higher fGCM levels than their free-ranging counterparts, regardless of sex, body condition, hierarchal status, age-class or dietary provisioning. The present study is the first to assess physiological stress responses across permanently captive, temporarily captive and free-ranging AWDs within the South African managed metapopulation, while incorporating the use of stable isotope analysis to quantify differences in dietary isotopic profiles between these different settings. Ultimately this demonstrates the usefulness of fGCM analysis as a tool for assessing animal welfare in both captive and free-ranging AWDs, and underpins the importance of understanding factors perceived as stressors for the management of the species. Keywords: animal welfare, body condition scoring, faecal glucocorticoid metabolite monitoring, managed metapopulation, stress, wildlife management.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere