Browsing by Author "Kays, Roland W."
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- Data packageData from: Eastern coyote home range, habitat selection and survival in the Albany pine bush landscape(2019-12-10) Bogan, Daniel A.; Kays, Roland W.In the northeast USA, top mammalian predators were extirpated through persecution and habitat loss. The coyote (Canis latrans) expanded into the northeast taking advantage of this vacant predator niche. Since 1970, coyotes have been widespread across all of mainland New York, yet no study has examined how well coyotes survive in suburban areas in this region and little is known of their ecological roles or potential to conflict with people. This information is important because in western states coyotes have high survival rates, a high degree of urban association and cause conflict with people. I studied survivorship and correlates of cause-specific mortality of coyotes using radio telemetry. The annual survival rate was 0.20 ± 0.14. There were no differences in survival rates between sexes, age classes, home range location, or capture methods. Collisions with vehicles (n = 7) and shooting (n = 6) accounted for the 2 major mortality factors. Coyotes that were killed by vehicles crossed roads more often than all other coyotes, though they did not have more roads within their home ranges. Coyotes that were shot had a larger mean and maximum open habitat patch size within their home ranges. High exploitation of the local coyote population may cause coyotes to avoid human-developed lands thus reducing the potential for negative interactions with people. I concurrently studied home range and habitat selection of coyotes in the suburban Albany Pine Bush landscape. Fixed kernel and minimum convex polygon (95%) home ranges (n = 17) averaged 6.81 km2 and 5.75 km2, respectively. Habitat analysis revealed that coyotes selected for natural habitat and avoided residential and commercial lands when locating a home range area and moving within the home range. Compositional analysis additionally ranked natural habitat as the most selected habitat at 2 spatial scales of selection (62.3% and 74.5%). Coyotes lived in small home ranges and primarily used the remaining natural lands in the suburban landscape. These results indicate that local coyotes maintain a natural ecological role and under existing conditions do not currently pose a threat to people and pets living adjacent to natural lands.
- Data packageData from: Shared decision-making drives collective movement in wild baboons(2015-06-19) Crofoot, Margaret C.; Kays, Roland W.; Wikelski, MartinNOTE: An updated and larger version of this dataset is available. See https://doi.org/10.5441/001/1.3q2131q5. ABSTRACT: Conflicts of interest about where to go and what to do are a primary challenge of group living. However, it remains unclear how consensus is achieved in stable groups with stratified social relationships. Tracking wild baboons with a high-resolution global positioning system and analyzing their movements relative to one another reveals that a process of shared decision-making governs baboon movement. Rather than preferentially following dominant individuals, baboons are more likely to follow when multiple initiators agree. When conflicts arise over the direction of movement, baboons choose one direction over the other when the angle between them is large, but they compromise if it is not. These results are consistent with models of collective motion, suggesting that democratic collective action emerging from simple rules is widespread, even in complex, socially stratified societies.
- Data packageData from: Study "Collective movement in wild baboons"(2021-08-10) Crofoot, Margaret C.; Kays, Roland W.; Wikelski, MartinWhen members of a group differ in locomotor capacity, coordinating collective movement poses a challenge: some individuals may have to move faster (or slower) than their preferred speed to remain together. Such compromises have energetic repercussions, yet research in collective behaviour has largely neglected locomotor consensus costs. Here, we integrate high-resolution tracking of wild baboon locomotion and movement with simulations to demonstrate that size-based variation in locomotor capacity poses an obstacle to the collective movement. While all baboons modulate their gait and move-pause dynamics during collective movement, the costs of maintaining cohesion are disproportionately borne by smaller group members. Although consensus costs are not distributed equally, all group-mates do make locomotor compromises, suggesting a shared decision-making process drives the pace of collective movement in this highly despotic species. These results highlight the importance of considering how social dynamics and locomotor capacity interact to shape the movement ecology of group-living species.
- Data packageData from: Thieving rodents as substitute dispersers of megafaunal seeds(2012-06-27) Jansen, Patrick A.; Hirsch, Ben T.; Emsens, Willem-Jan; Zamora-Gutierrez, Veronica; Wikelski, Martin; Kays, Roland W.The Neotropics have many plant species that seem to be adapted for seed dispersal by megafauna that went extinct in the late Pleistocene. Given the crucial importance of seed dispersal for plant persistence, it remains a mystery how these plants have survived more than 10,000 y without their mutualist dispersers. Here we present support for the hypothesis that secondary seed dispersal by scatter-hoarding rodents has facilitated the persistence of these large-seeded species. We used miniature radio transmitters to track the dispersal of reputedly megafaunal seeds by Central American agoutis, which scatter-hoard seeds in shallow caches in the soil throughout the forest. We found that seeds were initially cached at mostly short distances and then quickly dug up again. However, rather than eating the recovered seeds, agoutis continued to move and recache the seeds, up to 36 times. Agoutis dispersed an estimated 35% of seeds for >100 m. An estimated 14% of the cached seeds survived to the next year, when a new fruit crop became available to the rodents. Serial video-monitoring of cached seeds revealed that the stepwise dispersal was caused by agoutis repeatedly stealing and recaching each other’s buried seeds. Although previous studies suggest that rodents are poor dispersers, we demonstrate that communities of rodents can in fact provide highly effective long-distance seed dispersal. Our findings suggest that thieving scatter-hoarding rodents could substitute for extinct megafaunal seed dispersers of tropical large-seeded trees.