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Several aquatic sampling techniques are commonly used to detect and quantify amphibian larvae. Although many techniques have been standardized, comparisons among methods have been poorly studied. We employed a removal design to investigate the detection rate of amphibian larvae using box enclosures and evaluated the reliability of timed dipnet sampling relative to the more quantitative box enclosure sampling across 13 vernal pools. For these comparisons, we studied larvae of the endangered California Tiger Salamander (Ambystoma californiense; CTS) and the smaller and more abundant tadpoles of the Pacific Treefrog (Pseudacris regilla; PTF). Based on N-mixture model estimates, box enclosure sampling captured only 5% more of the CTS larvae present than PTF tadpoles, despite disparities in their sizes and estimated abundances. Dipnet sampling was slightly more effective at detecting CTS larvae than was enclosure sampling, while both methods equally detected PTF tadpoles. We found a strong relationship (R2 = 0.92) between the densities of CTS larvae estimated from dipnet sampling and those calculated from the more quantitative enclosure sampling, indicating that dipnet sampling is a reliable measurement of relative abundance. We conclude that timed dipnet surveys can be an important tool for monitoring populations of CTS, and possibly other lenticbreeding amphibians, especially given its relative efficiency that can be replicated across both time and space. [ABSTRACT FROM AUTHOR]

To combat biodiversity loss in the United States, imperiled species are protected under the federal Endangered Species Act (ESA), which is currently threatened by political initiatives seeking to weaken it and potentially transfer substantial authority to the states. To assess the conservation capacity of current state laws, we conducted a quantitative analysis of imperiled species protection within all 50 states by compiling data on all state‐listed species, ESA‐listed species, and IUCN Red List species in each state. We found that currently 16% of ESA‐listed species and 52% of IUCN imperiled species are not protected by any state law, and if the ESA were repealed these numbers could increase to 73% of ESA‐listed species and 81% of IUCN imperiled species unprotected. Although protection varies widely among states, our results suggest that revoking the ESA would be highly detrimental to imperiled species conservation and recovery in the United States. [ABSTRACT FROM AUTHOR]

The article offers information on activity of Gopherus polyphemus (Gopher Tortoise); and mentions immature G. polyphemus are less active in the mornings during summer months, compared to other months.

The article presents a report regarding the discovery and geographical distribution of the Ouachita Map Turtle, Graptemys Ouachitensis found in the Florida, U.S.

The article provides information on the geographical distribution of Trachemys venusta (Mesoamerican slider) which was discovered in a pond on campus in Miami-Dade County, Florida.

The article offers information on turtle specie Chelonia mydas. It mentions that Chelonia mydas have been negatively impacted by fibropapillomatosis around the world. It also mentions that there have tumors on the shoulder and small polyps on the neck, which appears to be the first record of fibropapillomatosis in the country.

Juvenile growth rate is a critical demographic parameter, as it shortens the time to maturity and often dictates how long individuals remain vulnerable to predation. However, developing a mechanistic understanding of the factors determining growth rates can be difficult for wild populations. The gopher tortoise ( Gopherus polyphemus ) is an ecosystem engineer threatened by habitat loss and deficient management of pinelands in the southeastern United States. We investigated the factors governing immature gopher tortoise growth and explored the use of drone-based imagery for habitat assessment by comparing predictive models based on ground-based plant surveys versus drone-derived data. From 2021 to 2022, we tracked and measured immature tortoises in native sandhill and human-modified, ruderal habitat in south-central Florida. Using quarterly, high-resolution drone imagery, we quantified plant cover types and vegetation indices at each occupied burrow and measured the frequency of occurrence of forage species by hand. Annual growth rates of immature tortoises in ruderal habitat were higher than those in sandhill and were the highest published for this species. Models based on drone-derived data were able to explain similar proportions of variation in growth as ground-collected measures of forage, especially during the late dry season when both types of models were most predictive. Habitat differences in forage nitrogen content were also more pronounced during this season, when dominant ground cover in ruderal habitat (bahiagrass) had much higher nitrogen content than dominant ground cover in sandhill (wiregrass). Despite concerns about potential growth-survival trade-offs, tortoises in ruderal habitat did not exhibit lower apparent survival. Our findings indicate that habitat dominated by nutritious non-native grass can provide a valuable supplement to native sandhill through the mechanism of increased growth rates due to higher forage quality. Finally, our study demonstrates that drone technology may facilitate management by providing less labor-intensive ways to assess habitat quality for this and other imperiled herbivores., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)