Seasonal shifts in the movement and distribution of green sea turtles Chelonia mydas in response to anthropogenically altered water temperatures

Anthropogenically altered water temperatures (AAWT) have the potential to affect the movement and distribution of marine ectothermic species. Green sea turtles (GSTs) Chelonia mydas are an ectothermic species observed inhabiting 2 sites with AAWT at the northern point of their geographical range in the eastern Pacific. An acoustic receiver array was deployed with temperature loggers at the San Gabriel River, Long Beach, CA, where 2 power plants discharge warm water into the river, and at the 7th St. Basin, Seal Beach, CA, a dredged shallow basin with warmer water compared to surrounding coastal habitats during the summer months. Juvenile GSTs (n = 22, straight carapace length = 45.2 to 96.8 cm) were tagged with acoustic transmitters. Turtles in the basin migrated into the river during winter months when temperatures dropped below 15°C. During the winter, turtles were most frequently detected at the river receiver stations adjacent to and downstream of the power plants. This suggests that GSTs use the warm effluent as a thermal refuge, avoiding colder areas upstream of the power plants and near the river mouth. In the summer, turtles were most frequently detected at receiver stations upstream of the power plants, potentially exploiting areas of the river with higher primary productivity. AAWT sustain the northernmost aggregation of GSTs in the eastern Pacific year round; however, based on GST thermal tolerance, this population is expected to change their movement patterns when the power plants discontinue discharging warm water by 2029

Habitat use and behavior of the east Pacific green turtle, Chelonia mydas in an urbanized system

Green sea turtles, Chelonia mydas, are known to inhabit populated and often urbanized areas. To understand turtle habitat use and behavior within these unique habitats, seven juvenile green turtles were fitted with acoustic transmitters (September 2012 – August 2014), of which two transmitters included an accelerometer (AP transmitter). One individual fitted with an AP transmitter was tracked using a passive acoustic array in an urbanized river, the San Gabriel River, Long Beach, CA (33°45’ N, 118°05’ W). Three additional turtles in this river and three turtles (one with AP transmitter) in a restored estuary (33°44’ N, 118°03’ W) in southern California were actively tracked for two non-consecutive 24-h periods. Those fitted with AP transmitters indicated that turtles were less active at night (0.58 ± 0.56 m/s2 and 0.50 ± 0.63 m/s2) than during the day (0.86 ± 0.63 m/s2 and 0.78 ± 0.60 m/s2) at both sites. Activity data and corresponding movements of the actively tracked turtle fitted with the AP transmitter were used to infer resting periods for other tracked individuals. Turtles rested near bridge pilings and runoff outflows in the river to potentially shelter from tidal flow. Turtles used significantly larger daily areas in the urbanized river (0.046 ± 0.023 km2) where resources may be patchier and less abundant, compared to turtles in the estuary (0.024 ± 0.012 km2) where large, dense eelgrass beds are present. Based on the habitat use and behaviors of green sea turtles, it appears that some green sea turtles are able to make use of both highly developed and restored habitats and likely benefit from certain aspects of development

The impacts of warming and hypoxia on the performance of an obligate ram ventilator

Climate change is causing the warming and deoxygenation of coastal habitats like Chesapeake Bay that serve as important nursery habitats for many marine fish species. As conditions continue to change, it is important to understand how these changes impact individual species\u27 behavioral and metabolic performance. The sandbar shark (Carcharhinus plumbeus) is an obligate ram-ventilating apex predator whose juveniles use Chesapeake Bay as a nursery ground up to 10 years of age. The objective of this study was to measure juvenile sandbar shark metabolic and behavioral performance as a proxy for overall performance (i.e. fitness or success) when exposed to warm and hypoxic water. Juvenile sandbar sharks (79.5-113.5 cm total length) were collected from an estuary along the eastern shore of Virginia and returned to lab where they were fitted with an accelerometer, placed in a respirometer and exposed to varying temperatures and oxygen levels. Juvenile sandbar shark overall performance declined substantially at 32 degrees C or when dissolved oxygen concentration was reduced below 3.5 mg l(-1) (51% oxygen saturation between 24-32 degrees C). As the extent of warm hypoxic water increases in Chesapeake Bay, we expect that the available sandbar shark nursery habitat will be reduced, which may negatively impact the population of sandbar sharks in the western Atlantic as well as the overall health of the ecosystem within Chesapeake Bay

Combined Effects of Acute Temperature Change and Elevated pCO2 on the Metabolic Rates and Hypoxia Tolerances of Clearnose Skate (Rostaraja eglanteria), Summer Flounder (Paralichthys dentatus), and Thorny Skate (Amblyraja radiata)

Understanding how rising temperatures, ocean acidification, and hypoxia affect the performance of coastal fishes is essential to predicting species-specific responses to climate change. Although a population’s habitat influences physiological performance, little work has explicitly examined the multi-stressor responses of species from habitats differing in natural variability. Here, clearnose skate (Rostaraja eglanteria) and summer flounder (Paralichthys dentatus) from mid-Atlantic estuaries, and thorny skate (Amblyraja radiata) from the Gulf of Maine, were acutely exposed to current and projected temperatures (20, 24, or 28 °C; 22 or 30 °C; and 9, 13, or 15 °C, respectively) and acidification conditions (pH 7.8 or 7.4). We tested metabolic rates and hypoxia tolerance using intermittent-flow respirometry. All three species exhibited increases in standard metabolic rate under an 8 °C temperature increase (Q10 of 1.71, 1.07, and 2.56, respectively), although this was most pronounced in the thorny skate. At the lowest test temperature and under the low pH treatment, all three species exhibited significant increases in standard metabolic rate (44–105%; p \u3c 0.05) and decreases in hypoxia tolerance (60–84% increases in critical oxygen pressure; p \u3c 0.05). This study demonstrates the interactive effects of increasing temperature and changing ocean carbonate chemistry are species-specific, the implications of which should be considered within the context of habitat. Associated dataset: Gail D. Schweiterman, Daniel P. Crear et al. 2019. Metabolic Rates and Hypoxia Tolerences of clearnose skate (Rostaraja eglanteria), summer flounder (Paralichthys dentatus), and thorny skate (Amblyraja radiata) https://doi.org/10.25773/qmew-c18

Metabolic Rates and Hypoxia Tolerences of clearnose skate (Rostaraja eglanteria), summer flounder (Paralichthys dentatus), and thorny skate (Amblyraja radiata)

These data were collected following methods described in the associated publication: LINK “Combined Effects of Acute Temperature Change and Elevated pCO2 on the Metabolic Rates and Hypoxia Tolerances of Clearnose Skate (Rostaraja eglanteria), Summer Flounder (Paralichthys dentatus), and Thorny Skate (Amblyraja radiata)”. Schweiterman, G.D. et al. 2019 Biology, 8(3), 56

Infant Outcomes Following Maternal Infection With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): First Report From the Pregnancy Coronavirus Outcomes Registry (PRIORITY) Study.

Infant outcomes after maternal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are not well described. In a prospective US registry of 263 infants, maternal SARS-CoV-2 status was not associated with birth weight, difficulty breathing, apnea, or upper or lower respiratory infection through 8 weeks of age

Extent and Causes of Chesapeake Bay Warming

Coastal environments such as the Chesapeake Bay have long been impacted by eutrophication stressors resulting from human activities, and these impacts are now being compounded by global warming trends. However, there are few studies documenting long-term estuarine temperature change and the relative contributions of rivers, the atmosphere, and the ocean. In this study, Chesapeake Bay warming, since 1985, is quantified using a combination of cruise observations and model outputs, and the relative contributions to that warming are estimated via numerical sensitivity experiments with a watershed–estuarine modeling system. Throughout the Bay’s main stem, similar warming rates are found at the surface and bottom between the late 1980s and late 2010s (0.02 +/- 0.02C/year, mean +/- 1 standard error), with elevated summer rates (0.04 +/- 0.01C/year) and lower rates of winter warming (0.01 +/- 0.01C/year). Most (~85%) of this estuarine warming is driven by atmospheric effects. The secondary influence of ocean warming increases with proximity to the Bay mouth, where it accounts for more than half of summer warming in bottom waters. Sea level rise has slightly reduced summer warming, and the influence of riverine warming has been limited to the heads of tidal tributaries. Future rates of warming in Chesapeake Bay will depend not only on global atmospheric trends, but also on regional circulation patterns in mid-Atlantic waters, which are currently warming faster than the atmosphere. Supporting model data available at: https://doi.org/10.25773/c774-a36

The Distribution of Total and Organic Mercury in Seven Tissues of the Pacific Blue Marlin, Makaira nigricans

Tissue samples from Pacific blue marlin (Makaira nigricans) were collected at a fishing tournament in Kona, Hawaii, in August 1973. Analyses of total and organic (methyl) mercury indicated that the marlin may be biotransforming methyl mercury to inorganic mercury such that about 90 percent of the body burden of mercury is in the inorganic form. Specific analysis of a subsample of the tissues showed that the difference between the total and organic mercury concentrations was equal to inorganic mercury by weight

The Index of Concentration at the Extremes (ICE) and Pregnancy-Associated Mortality in Louisiana, 2016–2017

ObjectivesSocial and contextual factors underlying the continually disproportionate and burdensome risk of adverse health outcomes experienced by Black women in the US are underexplored in the literature. The aim of this study was to use an index based on area-level population distributions of race and income to predict risk of death during pregnancy and up to 1 year postpartum among women in Louisiana.MethodsUsing vital records data provided by the Louisiana Department of Health 2016-2017 (n = 125,537), a modified Poisson model was fit with generalized estimating equations to examine the risk of pregnancy-associated death associated with census tract-level values of the Index of Concentration at the Extremes (ICE)-grouped by tertile-while adjusting for both individual and tract-level confounders.ResultsAnalyses resulted in an estimated 1.73 (95% CI 1.02-2.93) times increased risk for pregnancy-associated death for those in areas which were characterized by concentrated deprivation (high proportions of Black and low-income residents) relative to those in areas of concentrated privilege (high proportions of white and high-income residents), independent of other factors.Conclusions for practiceIn addition to continuing to consider the deeply entrenched racism and economic inequality that shape the experience of pregnancy-associated death, we must also consider their synergistic effect on access to resources, maternal population health, and health inequities

FRDC Project 1998/302 – Rock Lobster Enhancement and Aquaculture Subprogram:

Towards establishing techniques for large scale harvesting of pueruli and obtaining a better understanding of mortality rates B.F. Phillips, R. Melville-Smith, M. Rossbach, Y.W. Cheng