117 



General patterns of recolonization 



Regionally, recovery was slow, and the greatest increases in 

 eelgrass abundance occurred between 1955 and 1970. By the 1980's, 

 eelgrass had saturated most available substrate, but eelgrass 

 populations continue to expand in some areas today, and residents note 

 that eelgrass has not fully recovered to its former abundance in certain 

 bays . 



The onset of recolonization occurred mostly during the 1940 's and 

 early 1950's. In some areas, recolonization did not begin until the 

 1960's or later because they were remote from refuge populations, and 

 eelgrass propagation is slow over lOOO's of meters. This pattern 

 explains why some populations in this region and elsewhere (e.g., den 

 Hartog, 1987) are still recovering 50 years after the decline. 



The colonization of West Island, Great Neck, and Megansett Harbor 

 by eelgrass beds that survived in offshore or euryhaline environments 

 shows that eelgrass beds in estuaries or near fresh water sources were 

 not the sole refuge populations that later recolonized Buzzards Bay, and 

 were less important in the colonization of offshore areas and exposed 

 coasts. 



Around Buzzards Bay, once eelgrass began to colonize an area, the 

 time to reach peak abundance varied markedly. On a small scale (below 

 10 ha) growth is typically logistic, and habitat is saturated in 3 to 15 

 years (Costa, 1988 and in prep.). In some locations, such as on the 

 shallow shoal south of Indian Neck on Great Neck, Warehan, most 

 population growth occurrred during a 4 y period (1962-1966) , a few years 



