Understanding and Managing Living Resources

Tidal marsh birds (TMB) are important indicator species of healthy coastal marshes but are difficult to survey. However, understanding their population trends is critical to their conservation and the management of coastal ecosystems. Determining the effort required to survey and detect population declines in TMB species has important implications for their management. We surveyed four TMB species, clapper rail (Rallus crepitans), seaside sparrow (Ammospiza maritima), least bittern (Ixobrychus exilis), and common yellowthroat (Geothlypis trichas), during two breeding seasons in 2021-2022 using point counts across coastal Mississippi, U.S.A. We estimated their populations from predictions using N-mixture models with observational and landscape covariables. We used this dataset to model population declines in each species from 10, 30, and 50% for 3 years in the future. We conducted the same N-mixture analyses with the new datasets under different scenarios of survey effort to determine if surveys could be adaptively sampled based on reducing effort while also detecting different levels of population decline for each species. Accordingly, we decreased each of the survey routes in our sample design 1) by either 33% or 50%, 2) by eliminating either the routes with the most extreme (high and low) bird abundances or the middle abundance values, and 3) with either 2 or 3 repeat visits per season, before rerunning analyses. Overall, decreasing the survey routes while preserving the larger spatial structure of the study design resulted in similar population estimates as controls. It was more difficult to detect small versus large population declines overall as survey efforts decreased. Our results provide a model for adaptive monitoring of SMB species for the northern Gulf of Mexico.

The northern Gulf of Mexico and its bays, marshes, and wetlands are critical wintering grounds for many waterfowl species, such as diving ducks (Aythya spp.), green-winged and blue-winged teal. Large parcels of wintering habitat are owned by public and private entities that manage wetlands, thereby providing seasonal recreation for hunters. In the 25-year history of the Grand Bay National Estuarine Research Reserve (GNDNERR), there have been no targeted waterfowl abundance surveys, which could be used to inform the Grand Bay National Wildlife Refuge (GNDNWR) comprehensive conservation plan and habitat management decisions for the area. Unmanned aerial systems (UAS) will be used to estimate individual species abundance within the GNDNERR/NWR boundary. Large numbers of Redhead ducks (Aythya americana), Lesser Scaup (Aythya affinis), and Bufflehead ducks (Bucephala albeola) were seen in the GNDNERR/NWR during pilot surveys conducted in Nov 2023 – Feb 2024, suggesting that the area provides critical wintering habitat for waterfowl during their annual migration. Additionally, hunter surveys will be administered upon hunter egress to quantify hunter harvest rates within the GNDNERR/NWR boundaries. Harvest rates and hunter information will be used to gauge the importance of the area as a key resource for hunting opportunities to local communities. Ultimately, the results of this project will increase our understanding of waterfowl in the GNDNERR/NWR that will lead to improved management of this important resource.

Land managers' decisions about prescribing fire in high marsh ecosystems are complicated by uncertainty around the response of conservation priority birds, including black rails, yellow rails, and mottled ducks. High marsh is a unique habitat type, imminently threatened by sea level rise and characterized by a community of specialized emergent vegetation that tolerates irregular tidal inundation. The FireBird Project aims to determine the distribution and habitat use of black rails during the breeding and non-breeding seasons, what proportion of black rails are migratory versus year-round Gulf Coast residents, and the distribution and habitat use of non-breeding yellow rails and breeding mottled ducks. Our goal is to ultimately evaluate the target species' responses to prescribed fire within an adaptive management framework. To date, we have built a high marsh spatial data layer for the northern Gulf of Mexico region and determined that synoptic weather patterns, which could influence the ability of land managers to apply prescribed fire, have not changed in frequency since the 1970s. In addition to discussing our marsh mapping and climate-related results, we present preliminary results on the response of our three focal species to prescribed fire management of their habitats and provide insights into developing a comprehensive sampling design for three bird species that can be challenging to study.

The Mississippi Sound Estuary Program (MSEP) was created in 2023 with the purpose of connecting the restoration and investment efforts across Mississippi state agencies, federal agencies, academic institutions, non-governmental organizations, and community members to ensure that restoration and investment is done in a collaborate, cohesive, and science-based way. To achieve this, the MSEP has been working across these groups to develop a Comprehensive Conservation and Management Plan (CCMP) to guide MSEP activities for the next five years. Through many discussions, surveys, and workshops, we have identified an array of action items covering education and engagement, water quality, wildlife, and habitat. This presentation will describe both the process by which we have developed the CCMP as well as highlight projects with broad support in the region, such as creating a comprehensive project inventory.