Estimating the distribution of amphibians in terrestrial habitats surrounding wetlands is essential for determining how much habitat is required to maintain viable amphibian populations and how much habitat may be allocated to other land use practices. We apply univariate kernel estimation in a new manner to determine the distribution of amphibians during the non-breeding season. We summarized data from 13 radio telemetry studies that reported net maximum distance traveled from the breeding site for each individual (n = 404 individuals), and calculated a univariate kernel density estimate for all data combined. Kernel density estimation provides a function for the probability of an amphibian being present at a given distance from the breeding site and bootstrap methods allow for error estimates of isopleth values. Amphibians generally occurred at a short distance from the wetland (50% isopleth was at 93 m) and declined at greater distances (95% isopleth was at 664 m); however, use of habitat immediately adjacent (e.g., < 30 m) to the breeding site was lower than the peak for all species. The shape of the distribution was consistent for frogs and salamanders; however, the 95% kernel isopleth for the salamander estimate (245 m) was less than half the distance of the frog estimate (703 m), indicating that frogs distributed themselves at much greater distances from the breeding site than salamanders. Kernel estimates for the two western species, Rana luteiventris> and Bufo boreas>, did not peak near the breeding site as in the other species, suggesting that non-breeding habitat for these species is not located near breeding sites. We were unable to detect a statistical difference between sexes, but females tend to use habitat at greater distances from the wetland than males. Our results revealed that amphibians are not uniformly distributed in terrestrial habitats surrounding wetlands.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 27 • No. 1