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Environmental DNA (eDNA) sampling is a highly sensitive and cost‐effective technique for wildlife monitoring, notably through the use of qPCR assays. However, it can be difficult to ensure assay specificity when many closely related species co‐occur. In theory, specificity may be assessed in silico by determining whether assay oligonucleotides have enough base‐pair mismatches with nontarget sequences to preclude amplification. However, the mismatch qualities required are poorly understood, making in silico assessments difficult and often necessitating extensive in vitro testing—typically the greatest bottleneck in assay development. Increasing the accuracy of in silico assessments would therefore streamline the assay development process. In this study, we paired 10 qPCR assays with 82 synthetic gene fragments for 530 specificity tests using SYBR Green intercalating dye (n = 262) and TaqMan hydrolysis probes (n = 268). Test results were used to train random forest classifiers to predict amplification. The primer‐only model (SYBR Green results) and full‐assay model (TaqMan probe‐based results) were 99.6% and 100% accurate, respectively, in cross‐validation. We further assessed model performance using six independent assays not used in model training. In these tests the primer‐only model was 92.4% accurate (n = 119) and the full‐assay model was 96.5% accurate (n = 144). The high performance achieved by these models makes it possible for eDNA practitioners to more quickly and confidently develop assays specific to the intended target. Practitioners can access the full‐assay model online via eDNAssay (https://nationalgenomicscenter.shinyapps.io/eDNAssay), a user‐friendly tool for predicting qPCR cross‐amplification.

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After the removal of domestic cattle and water buffalo in 1982, the monsoonal wetlands of the Keoladeo National Park, India were rapidly overgrown by the grass Paspalum distichum L. We studied the decomposition of above-ground litter of Paspalum distiehum and that of ten submersed, floating-leaved, free-floating and emergent species, including the dominants in these wetlands prior to 1982. The only species that had decomposition rates as low as those of Paspalurn were the emergents, Pseudoraphis spinescens (R. Br.) Vickery and Typha angustata Bory & Chaub, which had very restricted distributions both before and after 1982. All the previous dominants had much higher decomposition rates. The turnover time for Paspalum litter was estimated to be greater than one year, while litter of the previous dominants all had turnover times of less than one year. Thus, a permanent litter layer could develop in these wetlands that had not been present previously.

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Vegetation (species composition and cover abundance) and peat and bedrock elevations were sampled along multiple transects across the head, near tail and far tail of two tree islands (designated the North Island and South Island) in Water Conservation Area 3-A. The heads of both islands are underlain by topographic highs in the bedrock. The peat layer was thinnest on the heads and much thicker on the near tail and far tail. The thinner peat layer on the heads of tree islands suggests that there is a mechanism that limits the maximum elevation of a tree island. Altogether 84 and 51 species were found on North Island and South Island, respectively. The results of an agglomerative hierarchical cluster analysis indicated that there were 9 and 7 plant assemblages on North Island and South Island, respectively. Although sometimes dominated by different species, the 7 assemblages on South Island had ecologically equivalent counterparts on North Island. Three plant assemblages (dry forest, wet forest, forest-fem) dominated by trees and shrubs (Chrysolalanus icaco (coco plum), Myrica cerifera (wax myrtle), Salix caroliniana (Carolina willow), and Schinus terebinthiflolius (Brazilianpepper)) were found primarily on the heads of the islands, which had the highest peat and bedrock elevations, and sometimes on the adjacent near tail. Sawgrass (Cladiumjamaicense) dominated plant assemblages (sparse sawgrass, dense sawgrass, decadent sawgrass, sawgrass-cattail) and wet prairie (Eleocharis cellulosa Torr. and Panicum hemitomon Schult.) were found at lower peat elevations and slough assemblages (Bacopa caroliniana, Eleocharis cellulosa, Nymphaea odorata, Utricularia purpurea) were found at the lowest peat elevations. There generally was no clear-cut relationship between bedrock or peat elevations and the distribution of the various sawgrass and wet prairie assemblages.