Comparison of pigeon guillemot, Cepphus columba, blood parameters from oiled and unoiled areas of Alaska eight years after the Exxon Valdez oil spill

In 1997, we compared the haematological and plasma biochemical profiles amo ng populations of pigeon guillemots, Cepphus columba, in areas oiled and no t oiled by the 1989 Exxon Valdez oil spill (EVOS) that occurred in Prince W illiam Sound (PWS), Alaska. Pigeon guillemot populations in PWS were injure d by EVOS and have not returned to pre-spill levels. If oil contamination i s limiting recovery of pigeon guillemots in PWS, then we expected that bloo d parameters of pigeon guillemots would differ between oiled and unoiled ar eas and that these differences would be consistent with either toxic respon ses or lower fitness. We collected blood samples from chicks at approximate ly 20 and 30 days after hatching. Physiological changes associated with chi ck growth were noted in several blood parameters. We found that only calciu m and mean cell volume were significantly different between the chicks in o iled and unoiled areas. Despite these differences, blood biomarkers provide d little evidence of continuing oil injury to pigeon guillemot chicks, eigh t years after the EVOS. Preliminary data from adults indicated elevated asp artate aminotransferase activity in the adults from the oiled area, which i s consistent with hepatocellular injury. Because adults have greater opport unities for exposure to residual oil than nestlings, we recommend studies t hat fully evaluate the health of adults residing in oiled areas. (C) 2000 E lsevier Science Ltd. All rights reserved.