Species‐specific responses to wetland mitigation among amphibians in the Greater Yellowstone Ecosystem

Abstract

Habitat loss and degradation are leading causes of biodiversity declines, therefore assessing the capacity of created mitigation wetlands to replace habitat for wildlife has become a management priority. We used single season occupancy models to compare the occurrence of larvae of four species of pond-breeding amphibians in wetlands created for mitigation, wetlands impacted by road construction, and unimpacted reference wetlands along a highway corridor in the Greater Yellowstone Ecosystem, United States. Created wetlands were shallow and had less aquatic vegetation and surface area than impacted and reference wetlands. Occupancy of barred tiger salamander (Ambystoma mavortium) and boreal chorus frog (Pseudacris maculata) larvae was similar across wetland types, whereas boreal toads (Anaxyrus boreas) occurred more often in created wetlands than reference and impacted wetlands. However, the majority of created wetlands (>80%) dried partially or completely before amphibian metamorphosis occurred in both years of our study, resulting in heavy mortality of larvae and, we suspect, little to no recruitment. Columbia spotted frogs (Rana luteiventris), which require emergent vegetation that is not common in newly created wetlands, occurred commonly in impacted and reference wetlands but were found in only one created wetland. Our results show that shallow created wetlands with little aquatic vegetation may be attractive breeding areas for some amphibians, but may result in high mortality and little recruitment if they fail to hold water for the entire larval period.

Predicting effects of water management on breeding abundance of three wading bird species

“…Spatiotemporal heterogeneity in resource availability is a common feature of large flood plains, and can benefit wildlife by protracting the availability of foraging opportunities (Fleming et al 1994, Armstrong et al 2016); furthermore, it can foster coexistence by dampening the negative effects of competition among species with similar prey requirements (Høberg et al 2002, DeAngelis et al 2005, Davidson et al 2012). Because some species may be more sensitive to changes in hydropatterns than others (Swartz et al 2020), an understanding of species‐specific responses to hydropatterns is required for multispecies management. Species‐specific models can also help managers determine if it is possible to optimize water levels for all species concurrently or if is it necessary to adopt management regimes that balance tradeoffs over the long term.…”

A co‐development approach to conservation leads to informed habitat design and rapid establishment of amphibian communities

“…Petranka et al., 2007). Examples of potential changes include macrophyte surface coverage (Fardell et al., 2018), shore tree coverage/shading (Oldham, Keeble, Swan, & Jeffcote, 2000), emergence of shrubs leading to long‐term pond loss (Erõs, Maloș, Horváth, & Hartel, 2020), frequency of desiccation/ hydroperiod (Swartz, Lowe, Muths, & Hossack, 2020) and fish introductions (Hazell, Hero, Lindenmayer, & Cunningham, 2004). While land managers are aware of the need to avoid such developments, ongoing monitoring is carried out by volunteers from the local citizen science group HARP.…”

Multi‐species occupancy modeling provides novel insights into amphibian metacommunity structure and wetland restoration

“…Wetland managers therefore need to ensure that emergent vegetation does not smother wetlands, and that some wetland sections may require careful thinning of emergent vegetation to provide open pools of water. Elsewhere, created wetlands with little aquatic vegetation are preferred breeding sites by some amphibian species (Porej and Hetherington 2005, Swartz et al 2020).…”