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Research about Unalaska Island

Source-linked reports with geographic coverage including Unalaska Island.

3 recordsLinked to original sources
USGS2012

Chronic hydrocarbon exposure of harlequin ducks in areas affected by the Selendang Ayu oil spill at Unalaska Island, Alaska

We evaluated chronic exposure of harlequin ducks (Histrionicus histrionicus) to hydrocarbons associated with the 2004 M/V Selendang Ayu oil spill at Unalaska Island, Alaska. We measured levels of hepatic 7-ethoxyresorufin-O-deethylase activity (EROD) in liver biopsy samples as an indicator of hydrocarbon exposure in three oiled bays and one reference bay in 2005, 2006, and 2008. Median EROD activity in ducks from oiled bays was significantly higher than in the reference bay in seven of nine pairwise comparisons. These results indicated that harlequin ducks were exposed to lingering hydrocarbons more than three years after the spill.

Alaska↗
USGS2009

Persistence rates and detection probabilities of bird carcasses on beaches of Unalaska Island, Alaska following the wreck of the M/V Selendang Ayu

Mark–recapture techniques were used to estimate persistence rates and detection probabilities of bird carcasses associated with the oil spill following the wreck of the M/V Selendang Ayu at Unalaska Island, Alaska. Only 14.6% of carcasses placed on beaches remained after 24 hours, and all carcasses that remained had been scavenged to some degree. Daily persistence rates for scavenged carcasses on subsequent days were substantially higher at 79.1%. Most carcasses (>98%) were removed by scavengers at night. When they made a single pass, observers searching beaches for carcasses that had washed ashore found only about 40% of carcasses known to be present. This detection probability did not vary between pairs of search teams or between beaches. Detection probability increased to about 70% when teams searched the same beach segment twice. Our data indicate that only a small fraction of beached carcasses would likely be found using standard beach survey protocols and search frequencies. These data emphasize the importance of measuring persistence and detection rates for each mortality event.

Alaska↗