Chesapeake Bay recovery and factors affecting trends: Long-termmonitoring, indicators, and insights

Peter J. Tango; Richard A. Batiuk

doi:10.1016/j.rsma.2015.11.010

Home/Archive/USGS

USGS · 70173989

Chesapeake Bay recovery and factors affecting trends: Long-termmonitoring, indicators, and insights

Peter J. Tango·Richard A. Batiuk

View original source ↗Export metadata ↓

Abstract

Monitoring the outcome of restoration efforts is the only way to identify the status of a recovery and the most effective management strategies. In this paper, we discuss Chesapeake Bay and watershed recovery and factors influencing water quality trends. For over 30 years, the Chesapeake Bay Program Partnership’s long-term tidal and watershed water quality monitoring networks have measured physical, chemical and biological parameters throughout the bay and its surrounding watershed underpinning an adaptive management process to drive ecosystem recovery. There are many natural and anthropogenic factors operating and interacting to affect the watershed and bay water quality recovery responses to management actions. Across habitats and indicators, the bay and its watershed continue to express a diverse spatial and temporal fabric of multiscale conditions, stressors and trends that show a range of health conditions and impairment s , as well as evidence of progress and degradation. Recurrent independent reviews of the monitoring program have driven a culture of continued adaptation of the monitoring networks to reflect ever evolving management information needs. The adherence to bay and watershed-wide consistent monitoring protocols provides monitoring data supporting analyses and development of scientific syntheses that underpin indicator and model development, regulatory assessments, targeting of management actions, evaluation of management effectiveness, and directing of priorities and policies.

Explore related subjects

Regional Studies in Marine Science Article

Source-reported bounding extent: 36.85764758564407° to 39.66914219401813° latitude; -76.9427490234375° to -75.465087890625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Peter J. Tango, Richard A. Batiuk. 2016. Chesapeake Bay recovery and factors affecting trends: Long-termmonitoring, indicators, and insights. https://doi.org/10.1016/j.rsma.2015.11.010

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2024

Long-term trends in abundance and potential drivers for eight species of coastal birds in the U.S. South Atlantic

The U.S. South Atlantic coastal region is used by many marine birds for foraging, reproduction, and migration. We developed standardized indices of relative abundance from long–term (1980–2016), semi-structured monitoring data (eBird) for eight species: Brown Pelican ( Pelecanus occidentalis ), Double-Crested Cormorant ( Nannopterum auritum ), White Ibis ( Eudocimus albus ), Wood Stork ( Mycteria americana ), Piping Plover ( Charadrius melodus ), American Oystercatcher ( Haematopus palliatus ), Clapper Rail ( Rallus crepitans ), and Northern Gannet ( Morus bassanus ). Following a period of stable or declining abundance from the 1980s through the 1990s, most species have shown stable or slightly upward trends through the late 2000s; Brown Pelican and Piping Plover have shown some evidence of recent declines. Species–specific correlations between abundance indices developed from presence/absence data and those developed from count data were positive for all species and ranged from 0.53 to 0.86. Dynamic factor analysis identified common trends in abundance among several species, in particular, Brown Pelican, Double–Crested Cormorant, and White Ibis. Model performance was improved with inclusion of an indicator of sea level rise, but not forage fish abundance or temperature, indicating habitat availability mediated by changing water levels may explain some of the underlying abundance trends. Our results provide baseline information on long–term trends for several important coastal birds that can help inform research, monitoring and conservation efforts in the U.S. South Atlantic region.

Florida, Georgia, North Carolina, South Carolina↗

USGS2023

Satellite tracking reveals use of Biscayne National Park by sea turtles tagged in multiple locations

Although historical observations date back to the 1800’s, there is little information on sea turtle occupancy within Biscayne National Park (BNP). The park is located along the Florida reef tract and is dominated by the Gulfstream, which acts as a corridor for many marine animals. Here we used satellite telemetry to determine areas of use in BNP for two species of imperiled sea turtles, loggerhead ( Caretta caretta ) and green ( Chelonia mydas ) turtles. We included data for turtles tagged between 2009–2021 at sites both within park waters and in five locations outside the park boundary; individuals were captured both in the water and on land. We tagged 60 individuals (female, n = "> = 48; male, n = "> = 3; immature, n = "> = 9); loggerheads (n = "> = 33) ranged in size from 66.2 to 109.9 cm CCL (curved carapace length) and green turtles (n = "> = 27) ranged in size from 39.1 to 111.9 cm CCL. We used behavioral switching state-space modeling (SSM) to obtain daily predicted positions for each turtle, classified turtle behavior within the park as either foraging, migration, or both foraging and migration, and summarized high-use areas for each species across all months of the year. Turtles used park waters year-round, with concentrated use of deeper waters during seasonal migrations. Across all 60 turtles, 21 spent their tracking time foraging within BNP boundaries and 30 used the park as part of their migratory pathway; five turtles used the park for both foraging and migration, and the remaining four had SSM points very close to the park. Loggerhead migration occurred from February through November, whereas green turtle migration was concentrated in August. Both turtle species exhibited high overlap (i.e., usage) with seagrass habitat. These findings are relevant as managers consider strategies to minimize anthropogenic impacts to resident and migratory sea turtles using park waters.

Florida↗

USGS2021

Stable isotopes used to infer trophic position of green turtles (Chelonia mydas) from Dry Tortugas National Park, Gulf of Mexico, United States

Evaluating resource use patterns for imperiled species is critical for understanding what supports their populations. Here we established stable isotope ( δ 13 "> δ13 C, δ 15 "> δ15 N) values for the endangered green sea turtle ( Chelonia mydas ) population found within the boundaries of Dry Tortugas National Park (DRTO), south Florida, USA. There is little gene flow between turtles sampled at DRTO and in other rookeries in Florida, underscoring the need to study this distinct population. Between 2008 and 2015 we collected multiple sample types (skin [homogenized epidermis/dermis], whole blood, red blood cells, plasma, carapace) from 151 unique green turtles, including 43 nesting females and 108 in-water captures; some individuals were resampled multiple times across years to evaluate consistency of isotope signatures. Isotopic ratios ranged from -27.3 to -5.4 for δ 13 "> δ 13 C and 3.7 to 10.6 for δ 15 "> δ 15 N. Using linear mixed models, we evaluated covariates (sample type, turtle size and year) that best explained the isotope patterns observed in turtle tissues. Predictions from the top model for δ 13 "> δ 13 C indicated a slight decrease over time and for δ 15 "> δ 15 N a slight increase in the middle sampling years (2010–2012); results indicated that turtle size appeared to be the driver behind the range in δ 13 "> δ 13 C and δ 15 "> δ 15 N observed in turtle skin. We found a pattern in stable carbon isotope values that are indicative of an ontogenetic change from an omnivorous diet in smaller turtles to a seagrass-based diet in larger turtles. When we compared the stable carbon and nitrogen isotope values of the samples collected from turtles with that of seagrasses found in DRTO, we found that turtles > 65 cm SCL had similar stable carbon isotope values to the seagrass species present. Results of this study suggest stable isotope analysis coupled with data for available resources can be useful for tracking and detecting future changes in green turtle resource shifts in DRTO.

Florida↗