by marine oil pollution (Vereshchagin 1946). Artificial feeding of oil caused a 

 reduction in mobility accompanied by diarrhea, loss of balance and coordination, 

 and tremors (Hartung 1963). Ingested oil has also been demonstrated as inter- 

 fering with egg- laying (Hartung 1963). 



In the southeastern United States, most Mallards frequent fresh water or 

 brackish or estuarine bays and marshes. Few appear in salt water (Stewart 1962), 

 In addition, the portion of the total population wintering in the southeastern 

 states is small. The risk to Mallards of oil development in that area is there- 

 fore relatively low. 



Table 3. Number of dead birds and number and percentage of dead Mallards 

 found after major oiling incidents. 



Area 



Dates 



Number Number 

 of oiled of dead Percent- 

 dead Mai- age of 

 birds lards Mallards 



Source 



Poole Harbour, 

 Dorset, England 



Medway Estuary, 

 Kent, England 



Tay Estuary, 

 Scotland 



N. Sealand, 

 Denmark 



Northeast Britain 



Jan. 1961 

 Sept. 1966 



Mar .-Apr . 

 1968 



Feb. -Mar. 

 1969 



Jan. -Feb. 

 1970 



North-central Kat- Mar. 1972 

 tegat, Denmark 



Waddensea , 

 Denmark 



Baltic sea coast , 

 Poland 



Firth of Forth, 

 southern Scotland 



Dec. 1972 



1970-1974 



Feb. 1978 



433 (a,b) 



2,748 (a) 



1,168 (b) 



2,376 (a) 



10,992 (a,c) 



4,759 (a) 



9,151 (a) 



3,867 (a,c) 



680 (a) 



36 



0.46 Bourne 1968a 



1.31 Bourne 1968a 



0.09 Greenwood and 

 Keddie 1968 



0.08 Joensen 1972b 



0.07 Greenwood et 

 al. 1971 



0.02 Joensen and 

 Hansen 1977 



0.03 Joensen and 

 Hansen 1977 



0.23 Gorski et 

 al. 1976 



0.14 Campbell et 

 al. 1978 



(a) Total includes only those birds identified to species, 



(b) Total includes both live and dead oiled birds. 



(c) Total includes some birds that were not oiled. 



177 



