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River otters (Lontra canadensis) are apex predators that bioaccumulate contaminants via their diet, potentially serving as biomonitors of watershed health. They reside throughout the Green-Duwamish River, WA (USA), a watershed encompassing an extreme urbanization gradient, including a US Superfund site slated for a 17-year remediation. The objectives of this study were to document baseline contaminant levels in river otters, assess otters’ utility as top trophic-level biomonitors of contaminant exposure, and evaluate the potential for health impacts on this species. We measured a suite of contaminants of concern, lipid content, nitrogen stable isotopes (δ15N), and microsatellite DNA markers in 69 otter scat samples collected from twelve sites. Landcover characteristics were used to group sampling sites into industrial (Superfund site), suburban, and rural development zones. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ether flame-retardants (PBDEs), dichlorodiphenyl-trichloroethane and its metabolites (DDTs), and polycyclic aromatic hydrocarbons (PAHs) increased significantly with increasing urbanization, and were best predicted by models that included development zone, suggesting that river otters are effective biomonitors, as defined in this study. Diet also played an important role, with lipid content, δ15N or both included in all best models. We recommend river otter scat be included in evaluating restoration efforts in this Superfund site, and as a potentially useful monitoring tool wherever otters are found. We also report ΣPCB and ΣPAH exposures among the highest published for wild river otters, with almost 70% of samples in the Superfund site exceeding established levels of concern.

We developed a new technique to quantify home ranges by using coordinate-based data that were collected at small time intervals and entered into a Geographic Information System (GIS). We used this technique (digitized polygons [DP]) and 4 other established methods to estimate home range sizes of groups of black howler monkeys (Alouatta pigra). We calculated the size of the area used by the study groups during the study period. The DP method used all available data points, excluded lacunae within home ranges, and accounted for spread of the group. The DP estimates of home range size were compared with 4 widely used methods: minimum convex polygon (MCP), grid-cell (GC), 95% harmonic mean (HM), and 95% adaptive kernel (AK). Sizes of home ranges ranged from 1 to 62 ha. Results of all procedures were strongly correlated (P < 0.001), although each gave very different estimates of home range sizes. The DP estimates were smaller than AK (P < 0.039) and MCP (P < 0.002) estimates and consistently (although not significantly) larger than GC methods (P = 0.99). There was no statistically significant or consistent difference between DP and HM estimates. Digitized polygons required the investigator to select path width and size of lacunae to exclude, but these decisions can be based upon biological information. This method may be the most appropriate technique to determine home range size with autocorrelated location data that can be converted to day-range paths.

We examined variation in the group structure of black howlers (Alouatta pigra) using the adult composition of 48 social groups. We compared the structure of groups at 5 sites with different population densities and variation in group structure over time with rising population density. In addition, we examined changes in the group structure of monkeys that were translocated from an area of high population density to an area with a much lower population density. We found at low population densities, groups comprised either heterosexual pairs or a single male with two females. At high population densities groups tended to be multimale and often contained >2 adult females. We suggest the relative costs and benefits of dispersal by maturing adults varies with population density, and in Alouatta pigra results in a shift from single to multimale groups of larger size with increasing population density.[PUBLICATION ABSTRACT]

This book is based in part on the symposium \"Nature in Fragments: The Legacy of Urban Sprawl,\" held in April 2000 at the American Museum of Natural History and co-sponsored by the museum's Center for Biodiversity and Conservation and the Wildlife Conservation Society's Metropolitan Conservation Alliance. The impetus behind the conference —and this book— was to create a platform from which to integrate biodiversity issues, concerns, and needs into the growing number of antisprawl initiatives, including the \"smart-growth\" and \"new urbanist\" movements. Our goal is to add biodiversity to the agenda of all who are creating more sustainable human environments, but who may not be fully considering ecological issues and opportunities associated with more informed development. A second, related goal is to deepen and broaden the discussion about sprawl's impacts on biodiversity and to include looking at ways in which sprawl affects species and alters or modifies natural communities, ecosystems, and processes.

Biotelemetry transmitters were implanted in adult female gaur (Bos gaurus) at the Bronx Zoo/Wildlife Conservation Park to establish baseline heart rate and body temperature value ranges in unrestrained animals and to document changes in these physiological functions when animals were exposed to different environmental conditions. Heart rate and body temperature were monitored using similar, but distinct, telemetry systems. Mean heart rates for five gaur ranged from 49.3 to 57.7 beats/min, and the mean body temperatures for two animals were 38.2°C and 38.8°C. Short-duration adversive stimuli caused brief three-fold increases in heart rate, but baseline rates returned once the stressors were removed. Moving gaur to novel environments or pairing them with nonaffiliates also resulted in heart rate increases. Body temperature was not affected by short-term stressors but was positively correlated with ambient temperature. The onset of ovulation may be predictable based on temperature spikes exhibited by the gaur at 19-22 day intervals.

Coyotes as top predators can help regulate the population of prey species like deer, rodents and small mammals in several ways.

  During the past year, with support from the DEC's Hudson River Estuary Program, we have been flying up the Hudson River twice per month, from the Tappan Zee Bridge to Troy Dam in a single-engine Cessna, counting and mapping swan locations with the aid of a global positioning system and digital maps. Rooted in the riverbed, these plants play a vital role in maintaining a healthy river by increasing oxygen levels and providing habitat for the bugs and worms at the bottom of the food chain and for fish.