How Did 

 the Benthic 

 Communities Recover? 



For years after the initial mortality, 

 the benthic communities were in 

 various stages of recovery. While 

 recovering, the communities were 

 characterized by reduced numbers of 

 species, and several abnormal varia- 

 tions in community structure. From 

 chemical monitoring, it was apparent 

 that, in many cases, the capacity of 

 the community to recover was com- 

 promised by the repollution, multiple 

 exposures, and persistence of the 

 No. 2 fuel oil in the environment. 



The communities that were recover- 

 ing after oiling showed many basic dif- 

 ferences when compared to normal 

 benthic communities which were repre- 

 sented by control stations. 



In light of this evidence, there is no 

 question that the normal functioning of 

 benthic communities was profoundly 

 affected for years after the West 

 Falmouth spill. 



Stages of Recovery - 



Number of Bottom Dwelling Species 



80 

 60 

 40 



20- 



1969 



Heavily Oiled Station 



1970 



1971 



Moderately Oiled Station 



Recovery of Affected 

 Communities 



• Smaller numbers of species. 



• Community dominance by oppor- 

 tunistic species. 



• Increased fluctuation, over time, 

 in the numbers of benthic 

 organisms making up the com- 

 munity. 



• Greater variation, over time, in the 

 species composition of the 

 recovering community. 



1969 



1970 



1971 



Source: Sanders, H.L., et al., IN PRESS. Anatomy of an Oil Spill: 

 The West Falmouth Study. Draft Submitted to EPA. 

 pp. 85, 86, 87. 



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