MITIGATING THE EFFECTS OF THE SHIFTING BASELINE SYNDROME BY UTILIZING THE BENTHIC MOLLUSCAN DEATH ASSEMBLAGE

Benthic marine faunas are currently experiencing rapid shifts in community structure which are already having deleterious effects on marine ecosystems. Since many systematic surveys of marine communities occurred after those communities had been disturbed, our knowledge of “what is natural” is incomplete: a phenomenon that has been termed the “shifting baseline syndrome.” Since ecological restoration efforts require an understanding of previous community states, alternative methods for delineating pre-disturbance community states are essential. In this study we apply analyses of life vs. death assemblage composition of communities that have undergone differing histories of disturbance. Live and dead mollusks obtained from transects constructed in two bays adjacent to San Salvador Island, Bahamas, were identified and community structure was compared. In Snow Bay, where little anthropogenic disturbance has occurred, diversity and relative abundance between life and death assemblages was more similar than the same metrics for life and death assemblages collected from Bone Fish Bay, where development has resulted in elevated levels of fecal coliform bacteria. We conclude that the changes to the benthic molluscan communities resulting from development in Bone Fish Bay have not yet been recorded by the attendant death assemblage. Thus, molluscan death assemblages may be used as proxies for pre-disturbance community states in environments that have already been degraded.