University Presentation Showcase: Undergraduate Division

Project Title

State conservation of North American amphibians: Effects of range fraction and biodiversity hotspots

Presenter Hometown

Louisville, KY

Major

Wildlife Management

Department

Biological Sciences

Degree

Undergraduate

Mentor

Cy Mott and Kelly Watson

Mentor Department

Biological Sciences

Abstract

The abundant center distribution hypothesis (ACH) predicts decreasing population densities as range margins are approached, but tests of the ACH are hindered by the logistical difficulties of range-wide sampling. Assessing species’ state-level conservation statuses could represent a viable alternative to range-wide sampling in tests of the ACH, given that sparser populations at range margins are more likely to elicit elevated conservation statuses. We hypothesized that states exhibiting small range fractions (i.e., marginal populations) of a species would exhibit elevated state-level conservation statuses. Using state-level conservations statuses for thirty North American amphibian species, we used linear regression to examine relationships between conservation status and the fraction of a species’ range located within that state. State, species range size, and range fraction within a state significantly affected state-level conservation status. Generally, smaller range fractions within states were associated with peripheral populations exhibited higher state-level conservation statuses, and a) smaller states and b) species with larger range sizes tended to exhibit higher state-level conservation statuses. State-level conservation statuses appear to reflect the patterns predicted by the ACH, and for anurans specifically, these results are in agreement with results from in situ population density estimates. Therefore, these results promote the use of conservation status across species ranges’ as a viable test of the ACH.

Presentation format

Poster

This document is currently not available here.

Share

COinS
 

State conservation of North American amphibians: Effects of range fraction and biodiversity hotspots

The abundant center distribution hypothesis (ACH) predicts decreasing population densities as range margins are approached, but tests of the ACH are hindered by the logistical difficulties of range-wide sampling. Assessing species’ state-level conservation statuses could represent a viable alternative to range-wide sampling in tests of the ACH, given that sparser populations at range margins are more likely to elicit elevated conservation statuses. We hypothesized that states exhibiting small range fractions (i.e., marginal populations) of a species would exhibit elevated state-level conservation statuses. Using state-level conservations statuses for thirty North American amphibian species, we used linear regression to examine relationships between conservation status and the fraction of a species’ range located within that state. State, species range size, and range fraction within a state significantly affected state-level conservation status. Generally, smaller range fractions within states were associated with peripheral populations exhibited higher state-level conservation statuses, and a) smaller states and b) species with larger range sizes tended to exhibit higher state-level conservation statuses. State-level conservation statuses appear to reflect the patterns predicted by the ACH, and for anurans specifically, these results are in agreement with results from in situ population density estimates. Therefore, these results promote the use of conservation status across species ranges’ as a viable test of the ACH.