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Geology topics

Bridget L. Borg

Publications and source records attributed to Bridget L. Borg.

2 recordsLinked to original sources

Genetic connectivity in a cooperatively breeding carnivore between two protected areas

Wildlife populations are increasingly threatened by human activities. Most studies, however, are often short in duration or do not encompass the large spatial extent necessary to measure the potential effects of human activities on population vital rates. Furthermore, the life history features of species with high fecundity and excellent dispersal capabilities can act as buffers against the potential negative effects of human activities on their populations. We used a 30-year dataset of genetic samples from gray wolves ( Canis lupus ) in Alaska, USA, to examine genetic connectivity and diversity between National Park units separated by a region with recurrent human-caused mortality. We found that the two protected populations were genetically similar and that dispersal events occurred between them even though they are > 450 km apart. We posit that intact ecosystems and a history of continuous distribution of wolves surrounding the affected regions likely maintained the genetic connectivity of wolves in the two protected areas.

Alaska

Determinants of gray wolf (Canis lupus) sightings in Denali National Park

Wildlife viewing within protected areas is an increasingly popular recreational activity. Management agencies are often tasked with providing these opportunities, yet quantitative analyses of factors influencing wildlife sightings are lacking. We analyzed locations of GPS-collared wolves and wolf sightings from 2945 trips in Denali National Park and Preserve, Alaska, USA, to provide a mechanistic understanding of how viewing opportunities are influenced by attributes of wolves and physical, biological, and harvest characteristics. We found that the presence of masking vegetation, den site proximity to the road, pack size, and presence of a wolf harvest closure adjacent to the park affected wolf sightings, and the influence of den proximity on sightings depended on harvest management. Wolf sightings increased with den site proximity to the road in years with a harvest closure adjacent to the park but not in the absence of the closure. The effect of the harvest closure on sightings was similar in magnitude to an increase in pack size by two wolves or a more than a two-fold decrease in masking vegetation. These findings were consistent across a 10-fold change in spatial resolution. Quantitative analysis of the factors influencing wildlife sightings provides valuable insight for agencies tasked with managing viewing opportunities.

Alaska