Research

American marten in the northeastern United States

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The American marten (Martes americana) is a forest carnivore native to boreal and sub-boreal forests of North America. It is an old-growth forest specialist dependent on deep snow pack at its southern range margin. The northeastern United States harbors the southern-most population of American martens, and is characterized by a dynamic history of range contractions and reintroduction attempts.

Genetic structure

We estimated genetic structure of marten populations at the southeastern periphery of their distribution, in Maine, New Hampshire, Vermont and New York. We discovered that a recently detected population in Vermont was likely descendant from a reintroduction attempt, which was previously believed to be unsuccessful. We also identified areas where martens may have persisted in relictual populations despite going undetected for decades. This work has been published in the April 2019 issue of Conservation Genetics.

Distribution and Habitat Connectivity

We estimated marten occupancy in the northeastern US from a diverse panel of local expert-elicited information. We identified significant relationships between estimated marten occupancy and tree canopy cover, spruce-fir land cover, temperature, elevation, and roads. This work has been published in the December 2018 issue of Animal Conservation.

Landscape Genetics

We used landscape genetics to identify landscape features that facilitate or impede marten gene flow in the northeastern US. We found that forest cover, elevation, and cold temperatures facilitate gene flow, and developed land cover impedes gene flow. We used a multi-scale approach with replication to reveal site- and scale-specific patterns in our data. Finally, we used spatial analysis to predict the locations of key gene flow corridors using our landscape genetics models. This work has been published Open Access in the April 2020 Issue of Heredity.

HdyCoverPhoto by Rav Bennett.

Salt marsh harvest mouse

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The salt marsh harvest mouse (Reithrodontomys raviventris) is a federally endangered species endemic to the San Francisco Bay area. My PhD research focuses on SMHM ecology and conservation.

Amargosa Vole

Amargosa vole | The Amargosa vole inhabits discontinuous poc… | Flickr

Diet Composition Analysis

The Amargosa vole (Microtus californicus scirpensis) is an endangered species endemic to extremely rare wetland habitat along a single river corridor in the Mojave Desert. These wetlands are near-monocultures of three-square bulrush. Consequently, Amargosa voles have been presumed to rely entirely upon bulrush for habitat and forage. We used a combination of nutritional analyses, microhistology, and DNA metabarcoding to evaluate the composition of Amargosa vole diet. We found a greater diversity of dietary items than expected, including 14 families of plants. The nutritional analysis suggested that bulrush alone was unlikely to support vole survival and reproduction, substantiating the diversity of diet items detected. This work is published Open Access in PLoS ONE.