Contrasting patterns of biodiversity across wetland habitats using single‐time‐point environmental DNA surveys

Abstract

Wildlife surveys are central to the conservation and restoration management of wetland habitats; however, the often laborious and costly nature of traditional survey methods can constrain the spatial and temporal extent and replication of survey efforts. Environmental DNA (eDNA) technologies now provide the opportunity to reduce some of these limitations, but applications in temporary and permanent freshwater marshes and meadows (herein referred to as ‘wetland habitats’) remain limited. This study investigates the performance of single‐time‐point eDNA surveys for characterizing fish, amphibian and bird assemblages of wetland habitats in south‐eastern Australia. Comparisons were made between coastal and inland wetlands, between wetlands of varying condition and between eDNA and traditional surveys. Findings show that eDNA surveys can provide comprehensive descriptions of faunal assemblages associated with wetland habitats, with resolution similar to that provided by traditional survey approaches. Analyses also revealed significant differences in patterns of biodiversity between wetland types (coastal vs. inland) but not between wetland habitats varying in condition. Overall, this study confirms that eDNA surveys provide a reliable option for undertaking wetland biodiversity assessments aimed at improving biodiversity data coverage for otherwise data deficient wetlands.

Optimised PCR assays for detecting elusive waterfowl from environmental DNA

“…The existing eDNA studies of wild bird species include determining the distribution of the North American marshland bird, the black rail ( Laterallus jamaicensis ) (Feist et al., 2022 ; Neice & McRae, 2021 ) and the Ridgway's rail ( Rallus obsoletus ) (Guan et al., 2023 ), detecting an endangered land bird, the Gouldian finch ( Chloebia gouldiae ), from drinking sites (Day et al., 2019 ), as well as detecting the kākāpō ( Strigops habroptilus ) from soil samples (Urban et al., 2023 ). Furthermore, studies have focused on detecting various avian species in diverse habitats, including urban waterbodies (Zhang et al., 2023 ), natural wetlands (Coleman et al., 2023 ), leaf swaps (Lynggaard et al., 2023 ), airborne dust (Johnson et al., 2023 ), air (Lynggaard et al., 2024 ), and spider webs (Newton et al., 2024 ). Additionally, several bird pollinators and an insectivorous bird were identified from eDNA collected from flowers (Jønsson et al., 2023 ; Newton et al., 2023 ).…”