NOAA Office of Protected Resources

(DWH) oil spill, a number of government agencies, academic institutions, consultants, and nonprofit organizations conducted lab- and field-based research to understand the toxic effects of the oil. Lab testing was performed with a variety of fish, birds, turtles, and vertebrate cell lines (as well as invertebrates); field biologists conducted observations on fish, birds, turtles, and marine mammals; and epidemiologists carried out observational studies in humans. Eight years after the spill, scientists and resource managers held a workshop to summarize the similarities and differences in the effects of DWH oil on vertebrate taxa and to identify remaining gaps in our understanding of oil toxicity in wildlife and humans, building upon the cross-taxonomic synthesis initiated during the Natural Resource Damage Assessment. Across the studies, consistency was found in the types of toxic response observed in the different organisms. Impairment of stress responses and adrenal gland function, cardiotoxicity, immune system dysfunction, disruption of blood cells and their function, effects on locomotion, and oxidative damage were observed across taxa. This consistency suggests conservation in the mechanisms of action and disease pathogenesis. From a toxicological perspective, a logical progression of impacts was noted: from molecular and cellular effects that manifest as organ dysfunction, to systemic effects that compromise fitness, growth, reproductive potential, and survival. From a clinical perspective, adverse health effects from DWH oil spill exposure formed a suite of signs/symptomatic responses that at the highest doses/concentrations resulted in multi-organ system failure.

Hundreds of southern right whale calves Eubalaena australis died on their calving ground at Pennsula Valds, Argentina from 2003 through 2011. During this period, the number of dead calves increased at a much greater rate than that of living calves over the preceding 32 yr, and with greater inter-annual variation. High mortality events occurred late in the calving seasons of 2005 and 2007, early in the seasons of 2008 and 2009, and were equally divided between early and late in 2010 and 2011. Calves that died late in the seasons of 2005 and 2007 were at least a meter longer (mean 7.3 m) than newborns, indicating that they had grown and presumably were healthy before dying. An unusual number of large calves (> 6 m) died early in the seasons of 2008 and 2009, suggesting that a population-wide process (e.g. nutritional stress) affected many mothers including older, larger mothers that tend to give birth to larger calves early in the season. Many tissue samples have been collected and analyzed, but no consistent lesions, pathologic processes or elevated levels of algal biotoxins have been identified to explain these recent mortality events. Here, we document the high mortality events, place them in historical context and describe ongoing efforts to identify their causes. As of 2010, the southern right whale sub-population that calves off Pennsula Valds was estimated to be less than 20% of its initial size before whaling; the ongoing high mortality of calves will significantly affect its recovery.

Three automated listening post-telemetry studies were undertaken in the Suwannee and Apalachicola estuaries to gain knowledge of habitats use by juvenile Gulf Sturgeons (Acipenser oxyrinchus desotoi) on winter feeding grounds. A simple and reliable method for external attachment of small acoustic tags to the dorsal fin base was developed using shrink-tubing. Suspending receivers on masts below anchored buoys improved reception and facilitated downloading; a detection range of 500–2500 m was realized. In the Apalachicola estuary, juvenile GS stayed in shallow water (< 2 m) within the estuarine transition zone all winter in the vicinity of the Apalachicola River mouth. Juvenile GS high-use areas did not coincide with high density benthic macrofauna areas from the most recent (1999) benthos survey. In the Suwannee estuary, juveniles ranged widely and individually throughout oligohaline to mesohaline subareas of the estuary, preferentially using mesohaline subareas seaward of Suwannee Reef (52% of acoustic detections). The river mouth subarea was important only in early and late winter, during the times of adult Gulf Sturgeon migrations (41% of detections). Preferred winter feeding subareas coincided spatially with known areas of dense macrofaunal benthos concentrations. Following a dramatic drop in air and water temperatures, juvenile GS left the river mouth and estuary, subsequently being detected 8 km offshore in polyhaline open Gulf of Mexico waters, before returning to the estuary. Cold-event offshore excursions demonstrate that they can tolerate full-salinity polyhaline waters in the open Gulf of Mexico, for at least several days at a time. For juvenile sturgeons, the stress and metabolic cost of enduring high salinity (Jarvis et al., 2001; McKenzie et al., 2001; Singer and Ballantyne, 2002) for short periods in deep offshore waters seems adaptively advantageous relative to the risk of cold-event mortality in shallow inshore waters of lower salinity. Thus, while juveniles can tolerate high salinities for days to weeks to escape cold events, they appear to make only infrequent use of open polyhaline waters. Throughout the winter foraging period, juvenile GS stayed primarily within the core area of Suwannee River mouth influence, extending about 12 km north and south of the river mouth, and somewhat seaward of Suwannee Reef (< 5 km offshore). None were detected departing the core area past either of the northern or southern acoustic gates, located 66 and 52 km distant from the river mouth, respectively.

Shortnose Sturgeon = SNS (Acipenser brevirostrum) is a small diadromous species with most populations living in large Atlantic coast rivers and estuaries of North America from New Brunswick, Canada, to GA, USA. There are no naturally land-locked populations, so all populations require access to fresh water and salt water to complete a natural life cycle. The species is amphidromous with use of fresh water and salt water (the estuary) varied across the species range, a pattern that may reflect whether freshwater or saltwater habitats provide optimal foraging and growth conditions. Migration is a dominant behaviour during life history, beginning when fish are hatchling free embryos (southern SNS) or larvae (northeastern and far northern SNS). Migration continues by juveniles and non-spawning adult life stages on an individual time schedule with fish moving between natal river and estuary to forage or seek refuge, and by spawning adults migrating to and from riverine spawning grounds. Coastal movements by adults throughout the range (but particularly in the Gulf of Maine = GOM and among southern rivers) suggest widespread foraging, refuge use, and widespread colonization of new rivers. Colonization may also be occurring in the Potomac River, MD–VA–DC (mid-Atlantic region). Genetic studies (mtDNA and nDNA) identified distinct individual river populations of SNS, and recent range-wide nDNA studies identified five distinct evolutionary lineages of SNS in the USA: a northern metapopulation in GOM rivers; the Connecticut River; the Hudson River; a Delaware River–Chesapeake Bay metapopulation; and a large southern metapopulation (SC rivers to Altamaha River, GA). The Saint John River, NB, Canada, in the Bay of Fundy (north of the GOM), is the sixth distinct genetic lineage within SNS. Life history information from telemetry tracking supports the genetic information documenting extensive movement of adults among rivers within the three metapopulations. However, individual river populations with spawning adults are still the best basal unit for management and recovery planning. The focus on individual river populations should be complemented with attention to migratory processes and corridors that foster metapopulation level risks and benefits. The species may be extirpated at the center of the range, i.e., the mid-Atlantic region (Chesapeake Bay, MD–VA, and probably, NC), but large rivers in VA, including the James and Potomac rivers, need study. The largest SNS populations in GOM and northeastern rivers, like the Kennebec, Hudson, and Delaware rivers, typically have tens of thousands of adults. This contrasts with southern rivers, where rivers typically have much fewer (<2500) adults, except for the Altamaha River (>6000 adults). River damming in the 19th and 20th Centuries extirpated some populations, and also, created two dysfunctional segmented populations: the Connecticut River SNS in CT–MA and the Santee-Cooper rivers–Lake Marion SNS in SC. The major anthropogenic impact on SNS in marine waters is fisheries bycatch. The major impacts that determine annual recruitment success occur in freshwater firstly, where adult spawning migrations and spawning are blocked or spawning success is affected by river regulation and secondly, where poor survival of early life stages is caused by river dredging, pollution, and unregulated impingement-entrainment in water withdrawal facilities. Climate warming has the potential to reduce abundance or eliminate SNS in many rivers, particularly in the South. In 1998, the National Marine Fisheries Service (NMFS) recommended management of 19 rivers as distinct population segments (DPSs) based on strong fidelity to natal rivers. A Biological Assessment completed in 2010 reaffirmed this approach. NMFS has not formally listed DPSs under the ESA and the species remains listed as endangered range-wide in the USA.

Understanding the spatial movements of threatened marine species, such as sea turtles, is essential as a means of informing appropriate conservation management. Although novel techniques for tracking spatial movements are becoming more widely available (such as satellite tracking), simple techniques such as mark-release-recapture remain effective. A flipper tagging and recovery program in Cuba tagged 210 loggerhead turtles over 14 yr and recovered 7% of the tags between 2 d and 3 yr later (mean = 296 d). All but one turtle was recaptured in Cuban waters, and data showed limited movement of turtles between northern and southern coasts. A further 50 turtles were recovered that had been tagged in foreign projects, the majority of which were from the USA (but also Mexico, The Bahamas, Canary Islands and Spain). A range of life stages of loggerhead turtles are found in Cuban waters year-round, and given that Cuba has the second largest reef in the Caribbean, it likely provides foraging habitat for significant numbers of loggerhead turtles from at least 6 different countries.

Baseline measurements were made on the

The Eastern Taiwan Strait (ETS) population of Indo-Pacific humpback dolphin (Sousa chinensis) is listed critically endangered in the Red List of Threatened Species by the International Union for Conservation of Nature due to its small population size and narrow distribution. The humpback dolphin habitats off the coast of Miaoli and Changhua are sites selected for future wind farms, therefore, the noise impact of pile driving on this critically endangered population is expected to be serious. This paper presents works done in (1) characterizing the sound field during the test pile driving and associated activities in the humpback dolphin habitat; (2) identifying dominant anthropogenic noise sources of the dolphin habitat during the construction of demonstration wind turbines and associated activities; and (3) examining the implications of the sound field from wind turbine construction and associated activities in relation to humpback dolphins’ hearing and communication. The results from the study can provide critical information and conservation recommendations for an environmental impact analysis for the full scale wind farm construction in 2017.

Under the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) is charged with conservation and management of marine mammals under NMFS’ jurisdiction. A regulatory mechanism is in place for NMFS to issue incidental take authorizations under the MMPA to operators whose activities may adversely affect marine mammals. As a mandate under the MMPA, mitigation and monitoring measures are prescribed to minimize any impacts on marine mammals and their habitat (prey species and acoustic environment) and to assess the degree of such impacts when such incidental take authorizations are issued. However, due to the limited visual range under and above water, monitoring measures using acoustical techniques are often required to supplement visual monitoring and to assist in making mitigation decisions. This presentation provides a summary of existing acoustic monitoring measures that are currently used in NMFS’ marine mammal incidental take authorizations; discusses the limitations, technical issues, practicality, and training needs involving acoustic monitoring; and highlights future needs in standardizing, improving, and expanding such techniques for more effective mitigation and monitoring measures.

Abstract Sharks are the primary predator of large immature and mature sea turtles, yet the shark species responsible for both lethal and non-lethal injuries are rarely identified because attacks are infrequently observed. Forensic analysis of bite wounds can be used to accurately assess size and potential shark species, especially when combined with species-specific feeding behavior, geographic distribution, and habitat preference. The objective of this study was to use forensic analysis of bite damage on sea turtles to infer shark size and species. Photographs from thirteen cases of documented shark scavenging ( N = 3) and predation ( N = 10) attempts on sea turtles were retrospectively analyzed, including nesting, free-ranging, and/or dead stranded loggerhead ( Caretta caretta ), green ( Chelonia mydas ), Kemp’s ridley ( Lepidochelys kempii ), and leatherback ( Dermochelys coriacea ) sea turtles in Florida and Alabama, USA from 2010–2020. Mean interdental distance (IDD) and bite circumference (BC) of wound marks on sea turtles strongly suggest that the bite marks were generated by white sharks ( Carcharodon carcharias ) in three cases, tiger sharks ( Galeocerdo cuvier ) in three cases, and bull shark(s) ( Carcharhinus leucas ) in one case. For three cases with less distinct wound patterns, two likely shark species were identified, and thereafter narrowed down to a single species based on bite mark characteristics. Due to indistinct IDD and BC ranges of bite wound patterns, a single shark species was not identified in three cases. Forensic analysis enables more accurate evaluations of which shark species predate and scavenge sea turtles, and is a useful technique for studying the behavioral interactions of sharks and turtles more closely.

Original provider: Barbara Schroeder Dataset credits: Data provider NMFS Office of Protected Resources Originating data center &lt;a href='http://www.seaturtle.org/tracking/' target='_blank'&gt;Satellite Tracking and Analysis Tool (STAT)&lt;/a&gt; This dataset is a summarized representation of the telemetry locations aggregated per species per 1-degree cell.