Deepwater Horizon Oil Shows Up in Sparrows
11/15/2016
LSU graduate student Allison Snider conducts research on Seaside Sparrows that reside
in Louisiana marshes year-round. New research shows Deepwater Horizon oil in these
native birds.Photo Credit: Philip Stouffer, LSU School of Renewable Natural Resources
BATON ROUGE – Scientists have identified the first evidence of Deepwater Horizon oil
in a land animal - the Seaside Sparrow. The scientists analyzed the diet and feathers
of sparrows collected more than a year after the oil spill. The birds that were captured
in habitats that were exposed to the oil had a different chemical signature in their
tissues than the birds that were found in areas of the marsh that were not exposed
to the oil. The scientists’ results show that the oil from the Deepwater Horizon oil
spill was incorporated into the prey and feathers of the exposed birds.
“We know that carbon from oil entered the offshore and nearshore food webs as demonstrated
for plankton, fish and filter feeders. But this is the first demonstration that carbon
from oil was also integrated into a terrestrial vertebrate species, the Seaside Sparrow,”
said LSU School of Renewable Natural Resources Associate Professor Sabrina Taylor.
The Seaside Sparrow is a year-round resident of Louisiana marshes. This new study
suggests that direct exposure to the toxic oil may have been detrimental to the birds’
reproductive success.
“These results suggest that the differences we have observed in sparrow gene expression
and reproductive success between oiled and unoiled sites may be caused by direct toxicological
effects not just habitat degradation or loss of prey species,” she said.
The researchers encourage further studies on the effect of the oil spill on terrestrial
species.

Oil from the 2010 Deepwater Horizon oil spill laps up into the Gulf of Mexico marsh.Photo Credit: Andrea Bonisoli Alquati, Cal Poly Pomona
“We tend to think of terrestrial ecosystems as safe from oil contamination. However,
the boundary between marine and terrestrial ecosystems is much less defined than we
assume. Species that live at the boundary are not only vulnerable to the toxic effects
of oil, but they can also be responsible for the transport of oil into the terrestrial
food webs. Future risk and damage assessments should incorporate an evaluation of
the potential threat to terrestrial wildlife from oiling operations and oil spills,”
said Andrea Bonisoli Alquati, a professor of environmental toxicology in the Department
of Biological Sciences at Cal Poly Pomona and the lead author of the study.
This research by scientists from the LSU School of Renewable Natural Resources, the
LSU Department of Oceanography and Coastal Sciences, the Cal Poly Pomona Department
of Biological Sciences and Austin Peay State University Department Biology was published
today in Environmental Research Letters.
Additional Link:
Incorporation of Deepwater Horizon oil in a terrestrial bird, Environmental Research
Letters: http://iopscience.iop.org/article/10.1088/1748-9326/11/11/114023
LSU has a video uplink studio with live broadcast capabilities. Contact us to set up an interview.
-30-
Contact Alison Satake
LSU Media Relations
225-578-3870
asatake@lsu.edu