Clinicopathological findings in sea turtles assessed during the Deepwater Horizon oil spill response

Abstract

During the BP Deepwater Horizon (DWH) oil spill in 2010, 319 live oiled sea turtles were rescued and admitted to rehabilitation centers for decontamination and veterinary care. Most turtles were small, surface-pelagic juveniles that were collected from oiled habitat distant from shore. Serial hematology, plasma biochemistry, and blood gas analyses were reviewed to characterize abnormalities relative to observed degree of oiling. Clinicopathological abnormalities upon admission indicated acute, nonspecific metabolic and osmoregulatory derangements that were attributable to a combination of events including stress, exertion, physical exhaustion, and dehydration related to oiling, capture, and transport. Specific toxicological effects reported in other taxa were not observed. Initial point-of-care blood data from one rescue center were evaluated using clinical assessment of physiological status for all turtles of all species with available data for pH, pCO 2 , sodium, and potassium. In addition, a prognostic model that was specifically developed for cold-stunned Kemp's ridley sea turtles Lepidochelys kempii was applied to oiled Kemp's ridley turtles from one center. Thirty-six percent of oiled turtles were identified as physiologically de ranged based on a clinical assessment of their physiological status, and 25% of oiled Kemp's ridley sea turtles exceeded the mortality risk threshold of the prognostic model. These results indicate that the physiological derangements in these animals were relatively severe and clinically relevant. Based on observations during the DWH spill, adverse physiological effects in sea turtles may be an important consequence of stress, exertion, physical exhaustion, and dehydration secondary to oiling, capture, and transport.

Long-term insights into marine turtle sightings, strandings and captures around the UK and Ireland (1910–2018)

“…The 2010 Deepwater Horizon oil spill (DWH) released an estimated 3.2 million barrels of crude oil into the waters of the northern Gulf of Mexico (DWH NRDA Trustees, 2016;Wallace et al, 2017). The Gulf of Mexico supports a large number of marine vertebrates including five species of marine turtle (including loggerhead and Kemp's ridley) (Stacy et al, 2017;Ylitalo et al, 2017). Marine turtles can be exposed to contamination in both the marine environment and on nesting beaches by a number of routes including via dermal/skin, inhalation/lungs, incidental consumption and diet (Lutz & Lutcavage, 1989;Lutcavage et al, 1995;Mitchelmore et al, 2017;Wallace et al, 2020).…”

Venous blood gas and biochemical analysis of wild captured green turtles (Chelonia mydas) and Kemp’s ridley turtles (Lepidochelys kempii) from the Gulf of Mexico

“…Several studies have evaluated blood gas, hematologic, and plasma biochemical values of green turtles from various regions of the world [6][7][8][9][10][11][12][13][14][15][16], but the Gulf of Mexico population has not been assessed. Blood data for healthy, wild Kemp's ridley turtles are lacking as most studies have focused on captive, stranded or rehabilitated turtles [12,[17][18][19][20], or turtles involved in fisheries interactions [21][22][23].…”

Spatio‐temporal distribution of sea turtle strandings and factors contributing to their mortality in south‐eastern Brazil

“…Dead, sick, or injured turtles found washed up on the coast can provide valuable information on their health status, and point to the primary causes of morbidity and mortality in a zone or region. Threats identified in stranded sea turtles include interactions with fishing gear (Monteiro et al, ; Tomás, Gozalbes, Raga, & Godley, ; Vélez‐Rubio, Estrades, Fallabrino, & Tomás, ), marine debris (Bugoni, Krause, & Petry, ; Santos, Andrades, Boldrini, & Martins, ; Tourinho, Sul, & Fillmann, ), boats and others watercrafts (Hazel & Gyuris, ; Work, Balazs, Summers, Hapdei, & Tagarino, ), hopper dredges (Goldberg et al, ), and oil and natural gas exploration/production activities (Stacy et al, ; Ylitalo et al, ). Natural factors, including diseases such as fibropapillomatosis (FP) (Chaloupka, Work, Balazs, Murakawa, & Morris, ; Reis, Pereira, et al, 2010), other neoplasms (Orós, Torrent, Calabuig, & Déniz, ), endoparasitosis (Flint et al, ), septicaemic processes (Goldberg et al, ), and hypothermia (Shaver et al, ; Vélez‐Rubio, Trinchin, Estrades, Ferrando, & Tomás, ), are also reported as causes of stranding.…”