Days that Count


January and February might be worth more if you lived in Florida.

In 1939, Charles Broley retired to Florida from Winnipeg, and threw himself into his lifelong hobby, leading him to one of the most important discoveries of the century.

After Charles Broley retired at age 58 from a successful banking career, he had more time for birds. The amateur birder became licensed by the US Fish & Wildlife Service to place ID bands on the legs of eagles. This was the early 1940s, when eagles nested in the tallest trees along the western Florida coast.  Only 166 eagles had ever been banded.

Charles learned to climb trees up to 90 feet tall, and to avoid attacks by adult eagles while he banded eagle chicks in the nests. He banded over a hundred chicks per year from Tampa to Fort Myers. Here in the midwestern US, eagles don’t hatch until early April, but most of Broley’s banding was done in January and February, on eaglets less than 12 weeks old.

Thanks to for Charles Broley photo by Joseph Janney Steinmetz. CreativeCommons license.

Suddenly in 1947, Broley’s eagle chick numbers dropped. Many eagles made nests but laid eggs that failed to hatch. Other nests had no eggs. Broley continued to survey declining numbers of nests until in 1958 he found only a single chick to band.

As people retrieved his eagle bands and sent them to Fish & Wildlife, biologists learned for the first time how far up the East coast the Florida birds ranged after they fledged, in search of fish.

Charles  suspected DDT as the cause of eagle nest failures, and raised awareness of industrial waste containing DDT which entered the water along which eagles fed. He spoke to many groups about eagles and their sudden decline. He published articles and received conservation awards. But Charles Broley died in 1959 before he could establish a definite cause for the eagle decline.

Using his meticulous records from work with more than 1,200 eagles, other researchers proved DDT was the cause of egg shells so thin the weight of adult birds crushed them in the nest. In 1962, Rachel Carson cited Broley’s work in Silent Spring, Chapter 8: “And No Birds Sing,” addressing for the first time the dangers of pesticides to health.

Eagle banding continues today, at least on the Mississippi River and in the Rocky Mountains, and possibly in up to 49 states, as the eagle is healthy again. For states along the east coast, The Center for Conservn Biology lists eleven active eagle banders in eleven states and one province. All these appear to be professionals for governmental or nonprofit organizations. Their tools now include GPS and Cessna aerial survey, but someone still has to climb.

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