Geology topics

Chelsea S. Kross

Publications and source records attributed to Chelsea S. Kross.

3 recordsLinked to original sources

USGS2025

Variation in detection distance of Eastern Black Rail (Laterallus jamaicensis jamaicensis) vocalizations by autonomous recording units

Autonomous recording units (ARUs) are an emerging technology that allows for passive monitoring of soniferous animals and soundscapes. Over the past decade, ARUs have become a popular tool for monitoring birds for their potential to reduce the labor and costs of traditional in-person sampling procedures. However, uncertainty surrounding factors affecting detection of avian taxa using ARUs can inhibit their monitoring efficacy. Eastern Black Rails ( Laterallus jamaicensis jamaicensis ) are a secretive marsh bird listed as a federally threatened species in the U.S.A. Eastern Black Rail vocalizations are difficult to detect by field personnel, and numerous in-person surveys can be required to confirm their presence at a site. While ARUs are an alternative for detecting Eastern Black Rails, it is unknown at what maximum distance an ARU can detect their vocalizations. We evaluated factors affecting the detection distance of simulated vocalizations for ARUs in four marsh vegetation types under a range of environmental conditions. Detection distances varied across models, vocalization and vegetation types, and call volume. Kickeedo vocalizations were detected at greater distances, and detection distances increased for all vocalization types in open vegetation. High relative humidity increased detection distances, while louder background noise decreased detection distances. High wind speeds in cordgrass ( Spartina spp .) decreased detection probability disproportionately relative to other vegetation types. Based on these results, considerations of survey area, vegetation type, and site condition can allow land managers and researchers to optimize Eastern Black Rail monitoring using ARUs. Given the substantial staff time needed to monitor this species, ARUs may increase the likelihood of detection and provide an efficient alternative to in-person monitoring.

Waterbirds↗

USGS2024

Ecology of an insular snake assemblage in coastal Maine

Wildlife populations at the peripheries of their distributions or on isolated islands often display divergent and poorly understood morphological or life-history characteristics compared to core populations. We used a capture–mark–recapture dataset collected over a 19-year period to characterize a northern, insular snake assemblage in coastal Maine. We captured 611 individual snakes of 4 species ( Thamnophis sirtalis [Common Gartersnake; n = 221 individuals], Diadophis punctatus [Ring-necked Snake; n = 258 individuals], Storeria occipitomaculata [Red-bellied Snake; n = 81 individuals], and Opheodrys vernalis [Smooth Greensnake; n = 51 individuals]) and recorded 104 recaptures. We provide some of the first data on growth, reproduction, and movement for these species in northern New England, expanding our understanding of insular and northern snake populations. Specifically, we found that Common Gartersnakes fed primarily on earthworms and amphibians and grew rapidly, in accordance with mainland populations, but exhibited smaller size at maturity and average litter sizes. We captured an unusually large number of Ring-necked Snakes, which are uncommon elsewhere in Maine, and recorded an apparently localized nesting area for this species, as well as relatively long-distance (230–300 m) dispersal away from that location. In our population, female Ring-necked Snakes mature in their third year, and this species exhibits weak sexual size dimorphism (SSD). We found the ecology of Red-bellied Snakes at our study site to be similar to other populations, with individuals feeding on slugs, and females maturing in their second year; however, our population exhibited the strongest pattern of (female-biased) SSD. Smooth Greensnakes were restricted to the most extensive old-field habitat within our study site and fed on a variety of arthropods. We confirmed communal nesting and short incubation period for this species and provide among the first data on growth and longevity (at least 7 years) of this relatively understudied species.

Maine↗

USGS2023

Qualitative value of information provides a transparent and repeatable method for identifying critical uncertainty

Conservation decisions are often made in the face of uncertainty because the urgency to act can preclude delaying management while uncertainty is resolved. In this context, adaptive management is attractive, allowing simultaneous management and learning. An adaptive program design requires the identification of critical uncertainties that impede the choice of management action. Quantitative evaluation of critical uncertainty, using the expected value of information, may require more resources than are available in the early stages of conservation planning. Here, we demonstrate the use of a qualitative index to the value of information (QVoI) to prioritize which sources of uncertainty to reduce regarding the use of prescribed fire to benefit Eastern Black Rails ( Laterallus jamaicensis jamaicensis ), Yellow Rails ( Coterminous noveboracensis ), and Mottled Ducks ( Anas fulvigula ; hereafter, focal species) in high marshes of the U.S. Gulf of Mexico. Prescribed fire has been used as a management tool in Gulf of Mexico high marshes throughout the last 30+ years; however, effects of periodic burning on the focal species and the optimal conditions for burning marshes to improve habitat remain unknown. We followed a structured decision-making framework to develop conceptual models, which we then used to identify sources of uncertainty and articulate alternative hypotheses about prescribed fire in high marshes. We used QVoI to evaluate the sources of uncertainty based on their magnitude, relevance for decision making, and reducibility. We found that hypotheses related to the optimal fire return interval and season were the highest priorities for study, whereas hypotheses related to predation rates and interactions among management techniques were lowest. These results suggest that learning about the optimal fire frequency and season to benefit the focal species might produce the greatest management benefit. In this case study, we demonstrate that QVoI can help managers decide where to apply limited resources to learn which specific actions will result in a higher likelihood of achieving the desired management objectives. Further, we summarize the strengths and limitations of QVoI and outline recommendations for its future use for prioritizing research to reduce uncertainty about system dynamics and the effects of management actions.

Ecological Applications↗