Osprey 



The numbers of American osprey (Pandion haliaetus ) declined along 

 the coast of Connecticut in the 1950 's and 1960 's due to the use of 

 pesticides. Grier (1982) identified the pesticide DDE as one of the 

 most persistent contaminants in the environment and one which posed the 

 greatest physiological threat to the osprey. Osprey populations along 

 the Connecticut River estuary decreased by as much as 30% per year (Ames 

 1966), and nests in other areas averaged only 0.2-0.4 young fledged per 

 active nest between 1957-1962 (Ames and Musereau 1964). After the ban 

 of DDT in 1972, reproduction rates of osprey from New York City to 

 Boston increased, reaching levels of 1.55/nest by 1981 (Spitzer et al. 

 1983) . The increase was attributed to reduced DDE concentrations in 

 osprey eggs (Spitzer et al. 1978). Osprey populations can recover if 

 young are produced at a rate of 0.8-1.30 per active nest (Henny and 

 Wright 1969; Spitzer et al. 1983) (Fig. 1). 



N i AREA OF SUSTAINED YELD jf 



\ r 



1 gsg 1 97 1 



1873 



1875 1877 1979 



YEAR 

 Mtlatone PoJrrt Connecfcut 



V--* 



1981 1983 



Figure 1. Average number of fledgelings per active nest for Millstone 

 Point compared to all of Connecticut. 



