Rendezvous Sites Research Articles

There is no place like home: Den and rendezvous site selection of Indian wolves in the human-dominated landscape of Maharashtra

There is no place like home: Den and rendezvous site selection of Indian wolves in the human-dominated landscape of Maharashtra

A field test of R package GPSeqClus: For establishing animal location clusters

Abstract The ability to track animals with Global Positioning System (GPS) collars opened an enormous potential for studying animal movements and behaviour in their natural environment. One such endeavour is to identify clusters of GPS locations as a way to estimate predator kill rate. Clapp et al. (2021) developed an R package (GPSeqClus) to assess a location dataset based on user‐defined parameters to identify clusters and their characteristics. These characteristics can then help to distinguish resting‐site clusters from kill sites of their large (>50 kg) prey. We identified location clusters of an adult male wolf Canis lupus on Ellesmere Island, Nunavut, Canada in July 2009 and tracked him until he died in April 2010. Identifying location clusters was challenging because the collar only obtained two GPS locations per day (12 h apart). In July 2010, we searched 30 of 52 location‐clusters we identified as kill/scavenge sites and found 17 of them as such, given they had muskox Ovibos moschatus or caribou Rangifer tarandus pearyi remains nearby. We also documented five wolf rendezvous sites, two den sites, and the wolf's death site to total 60 location‐clusters in all. We used a two‐step process in testing the R Package GPSeqClus (hereafter GPSeqClus): (1) compare the number of clusters our method discerned with the number identified by the new algorithm, and (2) compare the number of biologically significant clusters (e.g. den sites, kill/feeding sites) we found with the number the new algorithm located. We made these tests with GPSeqClus by varying the search radius, number of days at a site, and minimum number of locations required for a cluster. GPSeqClus compared well to our technique, with the best sub‐algorithm among the 25 we tested only missing three of our identified clusters and yielding six additional clusters. GPSeqClus identified 16 of the 17 confirmed sites of remains, all wolf home sites, and the wolf's carcass site. Identifying clusters using a 500‐m search radius, a 1.5‐day window, and a minimum of two GPS locations per cluster was suitable for a coarse GPS acquisition rate of two locations per day when prey are large, such as muskox or caribou. Given that GPSeqClus performed well with our coarse location dataset, we expect it will also perform even better with a collar acquiring more than two locations per day. Having a field‐tested utility such as GPSeqClus will enhance carnivore predation studies elsewhere.

Automatic recorders monitor wolves at rendezvous sites: do wolves adjust howling to live near humans?

Automatic recorders monitor wolves at rendezvous sites: do wolves adjust howling to live near humans?

Ecology of Indian wolf Canis lupus pallipes in the Great Indian Bustard Sanctuary, Nannaj, Solapur, Maharashtra, India

The Indian wolf, Canis lupus pallipes is an endangered carnivore of India listed in Schedule-1 of the Indian Wildlife (Protection) Act, 1972. There is not much information available on the species and with this perspective, the present study was initiated in the Great Indian Bustard Sanctuary in Maharashtra. Direct and indirect evidences were used to assess its population status and distribution, habitat use, feeding ecology, denning behaviour and wolf-human conflict emanating due to livestock depredation. Intensive ecological and behavioural studies were conducted at Nannaj on one pack between 1991 and 1994. The wolf survives all over the Sanctuary, which is densely populated by humans as elsewhere in its distribution range in India where wolf-human conflicts are common arising either due to livestock depredation or child-lifting. Usually, large packs were present in Blackbuck Antilope cervicapra areas whereas smaller packs inhabited areas not supporting healthy populations of Blackbuck. In Blackbuck poor areas, the wolf survived mainly on livestock. The Sanctuary supports 40-58 wolves. The wolves had a seasonal pattern of habitat use related to movement of prey and livestock. Wolves selected those areas as rendezvous sites which had higher prey density, vegetation cover, minimum human disturbance and were located close to water source. On an average wolves consumed 3.68 (S.E.=0.17) kg/wolf/kill and kill periodicity was 3.65 days (S.E.=0.58). Wolves preyed largely on blackbuck during the non-breeding period and livestock during denning period. Predation was higher on male blackbuck than females despite female biased sex ratio. The average litter size of three packs was recorded to be 5 (range 4-6). The dominant male and female wolves guarded the dens more often than the helpers. They used multiple dens for raising pups that were excavated and/or renewed during denning period. Important conservation problems of wolf have also been discussed in the paper.

Ecology of Indian wolf Canis lupus pallipes in the Great Indian Bustard Sanctuary, Nannaj, Solapur, Maharashtra, India

The Indian wolf, Canis lupus pallipes is an endangered carnivore of India listed in Schedule-1 of the Indian Wildlife (Protection) Act, 1972. There is not much information available on the species and with this perspective, the present study was initiated in the Great Indian Bustard Sanctuary in Maharashtra. Direct and indirect evidences were used to assess its population status and distribution, habitat use, feeding ecology, denning behaviour and wolf-human conflict emanating due to livestock depredation. Intensive ecological and behavioural studies were conducted at Nannaj on one pack between 1991 and 1994. The wolf survives all over the Sanctuary, which is densely populated by humans as elsewhere in its distribution range in India where wolf-human conflicts are common arising either due to livestock depredation or child-lifting. Usually, large packs were present in Blackbuck Antilope cervicapra areas whereas smaller packs inhabited areas not supporting healthy populations of Blackbuck. In Blackbuck poor areas, the wolf survived mainly on livestock. The Sanctuary supports 40-58 wolves. The wolves had a seasonal pattern of habitat use related to movement of prey and livestock. Wolves selected those areas as rendezvous sites which had higher prey density, vegetation cover, minimum human disturbance and were located close to water source. On an average wolves consumed 3.68 (S.E.=0.17) kg/wolf/kill and kill periodicity was 3.65 days (S.E.=0.58). Wolves preyed largely on blackbuck during the non-breeding period and livestock during denning period. Predation was higher on male blackbuck than females despite female biased sex ratio. The average litter size of three packs was recorded to be 5 (range 4-6). The dominant male and female wolves guarded the dens more often than the helpers. They used multiple dens for raising pups that were excavated and/or renewed during denning period. Important conservation problems of wolf have also been discussed in the paper.

DNA Barcoding Reveals Generalization and Host Overlap in Hummingbird Flower Mites: Implications for the Mating Rendezvous Hypothesis.

AbstractHummingbird flower mites are assumed to monopolize single host plant species owing to sexual selection for unique mating rendezvous sites. We tested the main assumption of the mating rendezvous hypothesis-extreme host specialization-by reconstructing interactions among tropical hummingbird flower mites and their host plants using DNA barcoding and taxonomic identifications. We collected 10,654 mites from 489 flowers. We extracted DNA from 1,928 mite specimens and amplified the cytochrome c oxidase I (CO1) DNA barcode. We analyzed the network structure to assess the degree of generalization or specialization of mites to their host plants. We recorded 18 species of hummingbird flower mites from three genera (Proctolaelaps, Rhinoseius, and Tropicoseius) interacting with 14 species of plants. We found that generalist mites are common, and congeneric mite species often share host plants. Our results challenge the assumption of strict specialization that supports this system as an example of mating rendezvous evolution.

Resource selection at homesites by wolves and eastern coyotes in a Canis hybrid zone

AbstractWe modeled resource selection by wolves (Canis spp.), eastern coyotes (C. latrans), and admixed canids during the pup‐rearing season at den and rendezvous sites (collectively, homesites) within a largely unprotected landscape proposed as the recovery zone for federally and provincially threatened eastern wolves (C. lycaon) in Ontario, Canada. Overall, canids selected wetlands, while avoiding secondary roads and open‐structure rock‐grass habitat patches. Packs with greater wolf ancestry selected wetlands and tertiary roads more strongly, while avoiding mixed conifer‐hardwood forests. Contrary to our prediction, canids with greater coyote ancestry did not establish homesites closer to roads, which likely mitigated their risk of human‐caused mortality during pup‐rearing. Packs exhibited increased selection of wetlands within territories as a function of increasing availability of wetlands. Packs with abundant access to wetlands may prioritize this habitat type to exploit beavers, a valuable prey species during pup‐rearing. Packs with higher pup survival selected hardwood forests and avoided conifer forests more than packs with lower pup survival. This is consistent with our understanding of habitat relations of the main prey species for canids in central Ontario and suggests that selecting prey‐rich habitat types at homesites increases fitness. A proposed goal of eastern wolf recovery is numerical and geographical expansion outside of the population core in Algonquin Provincial Park. Thus, our results provide valuable information for conservation by quantifying resource selection of wolves, coyotes, and hybrids during pup‐rearing and identifying links between fitness and homesite selection.

Pack size in humanized landscapes: the Iberian wolf population

Group living is an important behavioral feature in some species of mammals, although somewhat uncommon in the Order Carnivora. Wolves Canis lupus are highly social and cooperative carnivores that live in family groups, i.e. packs. The number of wolves in a pack affects social, reproductive and predatory behavior, thus conditioning population dynamics. Despite its relevance to management decisions, pack size has not been thoroughly studied in populations inhabiting human dominated landscapes such as the Iberian Peninsula. We estimated variation of wolf pack size from 1990 to 2018 in northern Spain, both in winter and summer. Winter data corresponded to direct observations and snow tracking at 42 localities (n = 253 data, 160 pack-years), whereas summer data corresponded to observations at rendezvous sites at 22 localities (n = 237 data, 43 pack-years). We estimated average pack size from the largest number of wolves recorded at each locality and year. Winter pack size averaged 4.2 ± 1.7 (mean ± SD) individuals. At summer rendezvous sites adult/subadult wolves (older than one year) averaged 3.1 ± 1.3 individuals, whereas pups averaged 4.0 ± 1.9. Generalized linear mixed models (GLMM) showed that pack size declined through the winter from 4.9 (4.2–5.6, 95% CI) wolves in November to 3.8 (2.9–4.9, 95% CI) wolves in April. We found no trend in pack size, neither in winter nor in summer. We discuss our results compared with other studies and populations worldwide, and its usefulness to comprehend the dynamics of this vulnerable population.

Berry Important? Wolf Provisions Pups with Berries in Northern Minnesota

ABSTRACTWolves (Canis lupus) primarily provision pups by catching mammalian prey and bringing remains of the carcass to the pups at a den or rendezvous site via their mouths or stomach. In August 2017, we observed an adult wolf regurgitating wild blueberries (Vaccinium spp.) to pups at a rendezvous site in the Greater Voyageurs Ecosystem, Minnesota, USA, which is the only known observation of wolves provisioning pups with wild berries. This observation, in combination with other evidence from the Greater Voyageurs Ecosystem, suggests wild berries might be a more valuable food source for wolves in southern boreal ecosystems than previously appreciated. © 2020 The Wildlife Society.

Male mate‐seeking and mating behaviors of Eucera nipponensis (Hymenoptera: Apidae) at a nectarless orchid habitat: Are empty flower patches a profitable rendezvous site?

AbstractMale solitary bees typically use emergence‐nesting areas and/or flower patches of food plants, where receptive females are relatively numerous, as rendezvous sites. However, mate‐seeking males have been also observed at food‐deceptive orchid patches, where numerous encounters with foraging females can hardly be expected, owing to the lack of floral rewards. Here, we describe the male mate‐seeking and mating behaviors of the Japanese long‐horned bee Eucera nipponensis at habitats of the food‐deceptive orchid Cymbidium goeringii. On the basis of the results, we report empty flower patches are not necessarily fruitless sites for mate‐seeking males because naive female bees, which are highly likely to be recently emerged and unmated, can be attracted to non‐rewarding orchids. We also suggest a possibility that a small number of the males could receive a “sexual reward” (i.e. mating opportunities), owing to the food‐deceptive orchid, in return for their pollination work. This occasional interaction could represent the initial stage in the evolution of sexually deceptive orchids from food‐deceptive orchids.

Predicting Spatial Risk of Wolf-Cattle Encounters and Depredation

Spatial variability in terrain, vegetation, and other features affect cattle and wildlife distribution on mountainous grazing lands of the western United States. Yet we have a poor understanding of how this spatial variability influences risk of wolf-cattle encounters and associated depredation. This knowledge gap severely limits our capacity to prevent or mitigate wolf-cattle conflict. Research addressing this problem was conducted in 2009−2011 at four study areas in western Idaho to evaluate models and mapping tools for predicting spatial risk of wolf-cattle encounters. Lactating beef cows grazing these study areas were instrumented with Global Positioning System (GPS) collars and tracked at 5-min intervals throughout the summer grazing season. Resource selection function (RSF) models, based on negative binomial regression, were developed from these GPS data and used to map the relative probability of cattle use in each study area. A wolf RSF model originally developed by Ausband et al. (2010) was applied to map study-area habitat types in terms of their relative suitability as wolf rendezvous sites. Spatial relationships between cattle and wolf selectivity patterns were used to classify and map wolf-cattle encounter risk to 5 classes (very high to very low) across each study area during the wolf rendezvous period (15 June−15 August). Validation analyses using GPS-based, wolf-cattle encounter observations (n = 200) revealed 84% of observed encounters occurred in areas of high- or very high−encounter risk (class 4 or 5). About 75% of confirmed wolf depredations recorded among three of four study areas were located in areas of high or very high risk. This new predictive understanding of wolf-cattle encounter risk will greatly aid livestock producers, resource managers, and policy makers in more effectively applying husbandry practices, allocating mitigation resources, and developing conflict mitigation plans and policies applicable throughout the mountainous western United States and potentially other regions of the world where wolves and cattle come into conflict.

Differential distribution of resources for females on a dioecious plant affects the small–scale distribution of male of an oligolectic bee

Females of the solitary digger bee Andrena florea Fabricius, 1793 (Hymenoptera, Andrenidae) nest in aggregations and collect pollen almost exclusively on dioecious plants of the genus Bryonia, making this species a good model to study the relationship between nest density, male density, male behaviour and female lecty. At a study site in the valley of the river Serio, in Italy, an aggregation of this bee showed low density of randomly distributed nests and was closely surrounded by B. dioica plants. Female nectar foraging and male feeding and mate–searching activity, confined to the host plants, peaked at similar hours across the day, while female pollen foraging peaked earlier. Males fed on plants of both sexes but seemed to perch waiting for females more frequently on male B. dioica leaves. Individual males more often visited only one of the male plants, for up to four days; here they did not interact aggressively with conspecifics, suggesting scramble competition in resource–based home ranges and not territoriality. These findings are preliminarily in accordance with the predicted resource–based rendez–vous sites at low nest density for oligolectic bees and the predicted occurrence of scramble competition in case of high male density. Additionally, males would maximize their mating opportunity by mainly perching on male plants, the only source of the most limited resource for females (pollen).

Use of space and homesite attendance by Iberian wolves during the breeding season

The persistence of large carnivores in human-dominated landscapes is conditional on the preservation of adequate ecological conditions during the reproduction period, when they may be particularly susceptible to human disturbance. However, little is known about the breeding behaviour of large carnivores in these landscapes, though this is important for conservation management. Here we describe the space use and homesite attendance patterns of wolves inhabiting humanised landscapes of north-western Portugal, based on GPS tracking of 11 individuals in 2008–2013. Parturitions (N = 3) occurred in late May, with pups remaining at natal dens for 24–85 days, after which they were moved to a first and then sometimes to a second rendezvous site. Two of these movements were associated with human disturbance events. Breeding females (N = 4) spent a large proportion of time with pups during pre-weaning (≈2 months after birth), leaving only at night during short periods; thereafter they progressively reduced time at homesites (i.e, natal dens and rendezvous sites), and increased both daily travel distances and daytime activity. Throughout the pup-rearing season, breeding females restricted their movements to within ≈2 km of homesites. Non-breeding females (N = 4) showed significantly lower attendance rates than breeding females, particularly during pre-weaning, and they had much less restricted movements throughout the breeding season, with activity occurring throughout the circadian cycle. Non-breeding males (N = 3) showed attendance and space-use patterns intermediate between breeding and non-breeding females, with movements largely concentrated within the same areas used by breeding females. Our findings suggest that breeding wolves may be particularly susceptible to human activities occurring within 2 km of homesites, although further research is needed to assess the ultimate effect of such disturbance on reproductive success and pup survival.

Hierarchical, multi‐grain rendezvous site selection by wolves in southern Italy

ABSTRACTFine‐scale knowledge of how anthropogenic effects may alter habitat selection by wolves (Canis lupus) is important to inform conservation management, especially where wolf populations are expanding into more populated areas or where human activity and development are increasingly encroaching on formerly pristine environments. From 1999 to 2003, we documented rendezvous sites (n = 31) used by wolves (n = 6 packs) in a previously unstudied wolf population in the southern Apennines, Italy (Pollino National Park [PNP]), where conditions are ideal to unveil behavioral adaptations of wolves living in human‐dominated landscapes. We adopted a hierarchical, multi‐scale habitat selection approach by using a set of environmental, topographic, and anthropogenic factors within multi‐grain resource selection functions (MRSFs) at the landscape and the territory extent. Habitat selection by wolves was scale‐dependent and different habitat components affected wolves at different grains. When establishing a territory at the landscape scale, wolves avoided areas featuring high densities of humans, paved roads, and trails, and they preferentially located territories where higher forest cover and rough terrain enhanced concealment and ensured reduced accessibility by humans. Concurrently, wolves also selected open areas and, at coarse grain, areas of high density of dirt roads and trails to enhance hunting and traveling efficiency. When selecting rendezvous sites within territories, wolves still selected for forest cover and lessened avoidance of anthropogenic features apparent at the lower order of selection. When choosing rendezvous sites, wolves also avoided low‐use anthropogenic linear features and rough terrain, unveiling trade‐offs in selection decisions across different spatial and temporal scales. Our results reinforce the notion that occurrence of wolves in human‐modified landscapes is shaped by avoidance of anthropogenic pressure, but they also indicate that rendezvous site selection by wolves conform to a hierarchical decision‐making process that is extent‐ and grain‐dependent. Spatially explicit models of rendezvous site selection such as the one we developed for PNP enhance management effectiveness for strategies such as regulating human access and activity during the pup rearing seasons, preventing human persecution, mitigating livestock depredations, and designing cost‐effective monitoring programs. © 2018 The Wildlife Society.

Predicting Spatial Risk of Wolf-Cattle Encounters on Rugged and Extensive Grazing Lands

Author(s): Clark, Patrick E.; Chigbrow, Joe; Johnson, Douglas E.; Williams, John; Larson, Larry L.; Roland, Tyanne | Abstract: Cattle grazing lands in the mountainous western United States are rugged, complex, and extensive. Terrain, vegetation, and other landscape features vary greatly across space. Risk of wolf-cattle encounters and potential for depredation loss certainly differ spatially as consequence of this variability. Yet, our understanding of this spatial risk is quite poor and this knowledge gap severely hampers our abilities to manage wolf-livestock interactions and mitigate conflicts. During 2009-2011, a research study was conducted at four study areas (USFS cattle grazing allotments) in western Idaho to evaluate and predict risk of wolf-cattle encounters. Each year, a random sample of 10 lactating beef cows from each study area was instrumented with GPS collars that logged positions at 5-minute intervals throughout the summer grazing season. Cattle resource selection was modeled using these GPS data and negative-binomial regression. An existing model was used to classify habitats within the study areas in terms of probability of use by wolves as rendezvous sites. Efficacy of this model was confirmed using scat, telemetry, and rendezvous site data. Spatial overlaps in the predicted selectivity of wolves and cattle were assessed and study area landscapes were then classified into five encounter-risk classes (very low to very high). Concurrent wolf and cattle GPS tracking data were used to document wolf-cattle encounters and thus evaluate the accuracy of this classification. About 94% of observed wolf-cattle encounters occurred within either the high or highest encounter-risk classes. Areas classified to the highest risk class were located on smooth, relatively flat slopes in concave terrain (e.g., stream terrace meadows) but not all were associated with surface water. Having this predictive understanding of where wolf-cattle encounters are most likely to occur will allow livestock producers and wildlife managers to more effectively apply resources, husbandry practices, and mitigation techniques to reduce conflict.

Plant Volatiles as Mate-Finding Cues for Insects.

Plant volatiles are used not only by herbivorous insects to find their host plants, but also by the natural enemies of the herbivores to find their prey. There is also increasing evidence that plant volatiles, in addition to species-specific pheromones, help these insects to find mating partners. Plant structures such as flowers, fruit, and leaves are frequently rendezvous sites for mate-seeking insects. Here we propose that the combined use of plant volatiles and pheromones can efficiently guide insects to these sites, where they will have access to both mates and food. This notion is supported by the fact that plant volatiles can stimulate the release of sex pheromones and can render various insects more receptive to potential mates.

Neandertals and early modern humans probably didn’t meet at rumored rendezvous site

Neandertals and early modern humans probably didn’t meet at rumored rendezvous site

Effects of breeder turnover and harvest on group composition and recruitment in a social carnivore.

Breeder turnover can influence population growth in social carnivores through changes to group size, composition and recruitment. Studies that possess detailed group composition data that can provide insights about the effects of breeder turnover on groups have generally been conducted on species that are not subject to recurrent annual human harvest. We wanted to know how breeder turnover affects group composition and how harvest, in turn, affects breeder turnover in cooperatively breeding grey wolves (Canis lupus Linnaeus 1758). We used noninvasive genetic sampling at wolf rendezvous sites to construct pedigrees and estimate recruitment in groups of wolves before and after harvest in Idaho, USA. Turnover of breeding females increased polygamy and potential recruits per group by providing breeding opportunities for subordinates although resultant group size was unaffected 1year after the turnover. Breeder turnover had no effect on the number of nonbreeding helpers per group. After breeding male turnover, fewer female pups were recruited in the new males' litters. Harvest had no effect on the frequency of breeder turnover. We found that breeder turnover led to shifts in the reproductive hierarchies within groups and the resulting changes to group composition were quite variable and depended on the sex of the breeder lost. We hypothesize that nonbreeding females direct help away from non-kin female pups to preserve future breeding opportunities for themselves. Breeder turnover had marked effects on the breeding opportunities of subordinates and the number and sex ratios of subsequent litters of pups. Seemingly subtle changes to groups, such as the loss of one individual, can greatly affect group composition, genetic content, and short-term population growth when the individual lost is a breeder.

Attraction-repulsion among top predators following reintroduction efforts

Much of our understanding of the effects top predators play in structuring ecological communities are from studies documenting ecological changes following the recovery or reintroduction of large carnivores. Reintroduced predators, for example, may create unanticipated competition scenarios that influence local carnivore guilds. Here, we tested whether newly released Mexican gray wolves in Chihuahua, Mexico interacted with resident pumas, as a first step in exploring potential competition between the two species. We employed GPS data and novel methods offered by MoveMine 2.0 to quantify attraction-repulsion between individual wolves and pumas during two time periods: the first when wolves were free roaming, and the second when they restricted their movements to an area around their den and rendezvous site to protect and provide for pups. In summary, attraction-repulsion analyses conducted with MoveMine provided meaningful outputs, but we would highlight the importance of fieldwork to interpret interactions and significance values calculated between pairs. We found that high attraction values resulted from mutual attraction between wolves in the same pack, between wolves and one puma they repeatedly harassed, as well as between two pumas that repeatedly exhibited social tolerance for each other. Thus, the analyses offered by MoveMine provided a powerful means of identifying interactions and assessing attraction-repulsion relevant to questions of intra- and interspecific competition, but required intimate knowledge of the species studied and the interactions between them to interpret outputs correctly.

Observation of an Eastern Wolf (<i>Canis</i> sp. cf. <i>lycaon</i>) Caching Food in a Sphagnum Bog in Algonquin Provincial Park, Ontario

We report summer caching of a partial carcass of a White-tailed Deer (Odocoileus virginianus) fawn by an Eastern Wolf (Canis sp. cf. lycaon) in a Sphagnum bog in Algonquin Provincial Park, Ontario, Canada. The microhabitat conditions in bogs (i.e., low temperature, acidity, and organochemical compounds) likely inhibit food spoilage, making bogs potentially important sites for food caching. Wolves in Algonquin Park experience low summer food availability and high pup mortality from starvation. Caches likely serve as necessary reserve food stores for adults and pups. Recent research has shown that wetland habitats are important den and rendezvous sites for Algonquin Eastern Wolves based on prey availability and, we suggest, perhaps for food storage and accessibility. This caching behaviour was recorded on video. We recommend that future research investigate Eastern Wolf selection of food-caching sites, as a complement to other spatial ecology studies.