Oral Presentations
Low Amphibian Larvae Recruitment at a Restoration Site in Western Montana: Is Fish Predation Responsible?
Presentation Type
Presentation
Faculty Mentor’s Full Name
Erim Gómez
Faculty Mentor’s Department
Wildlife Biology
Abstract / Artist's Statement
Global amphibian populations are declining at an alarming rate, yet amphibians are often left out of restoration planning and effort. This means that the impacts of restoration on amphibians are not well understood. At a Superfund restoration site in western Montana, Milltown State Park, amphibian larvae detectability was extremely low in 2021, despite successful amphibian breeding. This study aimed to determine whether the low detectability of Columbia spotted frog (Rana luteiventris) and long-toed salamander (Ambystoma macrodactylum) larvae at this site might be due to predation by fish in many of the ponds. In April-May of 2022, we counted the number of Columbia spotted frog egg masses in eight permanent ponds and four seasonal ponds at Milltown to establish a baseline of breeding events. We then conducted repeated catch-and-release sampling of amphibian larvae at the identified sites in June and July, determining fish presence at this time. We found weak evidence that the catch of long-toed salamander larvae was lower in ponds that contained fish compared to ponds that did not have fish, but no evidence that fish presence determined the catch of Columbia spotted frog larvae. The largest proportion of Columbia spotted frog and long-toed salamander larvae caught at Milltown came from a single permanent, fishless pond on the park's south end, supplying 86% and 63% of the total larvae, respectively. It also contained the majority of Columbia spotted frog egg masses (74%). While we could not attribute this finding to fish absence alone, we speculate it may play a large role in its suitability as a habitat. Further studies are needed to determine what makes this pond different from the rest, and that information could be used to inform future pond construction methods at restoration sites in western Montana.
Category
Life Sciences
Low Amphibian Larvae Recruitment at a Restoration Site in Western Montana: Is Fish Predation Responsible?
UC 331
Global amphibian populations are declining at an alarming rate, yet amphibians are often left out of restoration planning and effort. This means that the impacts of restoration on amphibians are not well understood. At a Superfund restoration site in western Montana, Milltown State Park, amphibian larvae detectability was extremely low in 2021, despite successful amphibian breeding. This study aimed to determine whether the low detectability of Columbia spotted frog (Rana luteiventris) and long-toed salamander (Ambystoma macrodactylum) larvae at this site might be due to predation by fish in many of the ponds. In April-May of 2022, we counted the number of Columbia spotted frog egg masses in eight permanent ponds and four seasonal ponds at Milltown to establish a baseline of breeding events. We then conducted repeated catch-and-release sampling of amphibian larvae at the identified sites in June and July, determining fish presence at this time. We found weak evidence that the catch of long-toed salamander larvae was lower in ponds that contained fish compared to ponds that did not have fish, but no evidence that fish presence determined the catch of Columbia spotted frog larvae. The largest proportion of Columbia spotted frog and long-toed salamander larvae caught at Milltown came from a single permanent, fishless pond on the park's south end, supplying 86% and 63% of the total larvae, respectively. It also contained the majority of Columbia spotted frog egg masses (74%). While we could not attribute this finding to fish absence alone, we speculate it may play a large role in its suitability as a habitat. Further studies are needed to determine what makes this pond different from the rest, and that information could be used to inform future pond construction methods at restoration sites in western Montana.