Heavy metals contamination and body condition of wintering guillemots (Uria aalge) at the Belgian coast from 1993 to 1998

A sample of 166 common guillemots (Uria aalge) recovered from Belgian beach es during five wintering seasons, from 1993-1994 to 1997-1998, were examine d. At necropsy, postmortem examination including body mass, fat reserves, p resence or not of intestinal contents, eventual status of oiling, and patho logical changes (cachexia, acute hemorrhagic gastroenteropathy (GEAH)) was attributed to each individual. Mild to severe cachexia, a pathology charact erized by moderate to severe atrophy of the pectoral muscle as well as redu ced amounts or absence of subcutaneous and/or abdominal fat, was observed f or most specimens (85.8%). Heavy metal analyses (Cu, Zn, Fe, Cd, Ni, Cr, an d Pb) of the tissues (typically liver, kidney, and pectoral muscle) were pe rformed, and total lipids were determined Giver and pectoral muscle). The g uillemots collected at the Belgian coast exhibited higher Cu and Zn concent rations compared to individuals collected in more preserved areas of the No rth Sea such as the northern colonies. A general decrease of their total bo dy mass as well as liver, kidney, and pectoral muscle mass was associated t o increasing cachexia severity. Moreover, significantly increasing heavy me tal levels (Cu and Zn) in the tissues as well as depleted muscle lipid cont ents were observed parallel to increasing cachexia severity. On the contrar y the organs' total metal burden barely correlates to this status. These ob servations tend to indicate a general redistribution of heavy metals within the organs as a result of prolonged starvation and protein catabolism (cac hectic status). Such a redistribution could well be an additional stress to birds already experiencing stressfull conditions (starvation, oiling). (C) 2000 Academic Press.