I can't remember when I have seen so many Osprey these days they seem like they are on every day-marker. I had the opportunity to watch these birds for about an hour from the boat. Osprey populations declined drastically in many areas in the 1950s and 1960s; this appeared to be in part due to the toxic effects of insecticides such as DDT on reproduction. The pesticide interfered with the bird's calcium metabolism which resulted in thin-shelled, easily broken or infertile eggs. Possibly because of the banning of DDT in many countries in the early 1970s, together with reduced persecution, the osprey, as well as other affected bird of prey species, have made significant recoveries.