Identification

Title

Toxicological estimation of mortality of oceanic sea turtles oiled during the Deepwater Horizon oil spill

Abstract

Using multiple lines of evidence, we estimated the mortality of oceanic sea turtles that were minimally to moderately oiled by the 2010 BP Deepwater Horizon (DWH) oil spill in the Gulf of Mexico. Using estimates of the oil ingested by oceanic sea turtles and comparing them to toxic endpoints following oil ingestion in turtles and other vertebrate species, we derived an estimated percentage of mortality for oil-exposed oceanic sea turtles. Oil ingestion (mg kg(-1) BW d(-1)) in oceanic sea turtles was estimated based on extent of oiling categories assigned by a sea turtle technical working group (STTWG) as follows: non-oiled (0), minimally oiled (1), lightly oiled (2), moderately oiled (3) and heavily oiled (4). Because the STTWG concluded that 100% of heavily oiled turtles would have died from the physical effects of heavy oiling, we limited our assessment of mortality to turtles in categories 0 to 3 and estimated how many of these turtles would have died from ingestion of oil. The estimated mortality was 85% for category 3, 50% for category 2 and 25% for category 1. Visibly non-oiled turtles (category 0) were assigned 0% mortality. To calculate the overall mortality for all turtles, the mortality estimations for categories 0 to 3 were applied to the numbers of turtles observed with different degrees of oiling, as documented by direct capture operations during the DWH spill. We concluded that, overall, approximately 30% of all oceanic turtles in the region affected by the DWH spill that were not heavily oiled would have died from ingestion of oil.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d78c9z1v

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2017-01-31T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact