In spring of 2021, I wrote the Habitat Article for the local River Towns Magazine. The below is the blog version of the post – enjoy!

A once dying raptor, Bald Eagles now have healthy habitat they need to thrive! In the 1960’s and 70’s, the Bald Eagle, our National symbol, was on the verge of extinction. DDT, a harsh chemical insecticide was sprayed all over agricultural fields and roadsides. As the rains fell it washed into waterways. Bald Eagles would catch fish, their ideal food source, in those polluted waters and ingest the insecticide. Their eggs became too thin and corroded to properly hatch, and the bird almost completely disappeared. 

In 1972, DDT was banned, and the Delaware River was cleaned. Over the next few decades, as the water quality and local habitat, including streams like the Tohickon, improved, the Bald Eagles were able to re-establish themselves in the River Towns region.

Diane Allison, local birding expert and data compiler for the Central Bucks Christmas Bird Count, a Community Science project put on by the National Audubon Society, was able to provide some historical data. The first Bald Eagle observed in the Christmas Bird Count was in 1966. For many years to come, no other eagles were observed until 1975. Finally, in 2015, there was evidence that the local habitat was healthy enough to sustain successful nests. There were 11 Bald Eagles observed that year, and each year since, the numbers rose! In the 2019 Christmas Bird Count, 19 Bald Eagles were recorded.

While these Community Science projects help to provide scientists with a general idea of population growth, it’s not unlikely that the data doesn’t fully depict populations. Only birds observed within a certain timespan are counted, and due to the fact that birds can move freely, may be counted too many times or not at all if they are absent from the count location. However, these counts do provide valuable information on general trends, climate change impact, and movement over time.

Allison contributes these numbers to decreased DDT and cleaner habitat. Many wildlife-lovers may be concerned about the amount of human recreation along the river causing a disturbance to eagles. Despite tubing, kayaking, fishing, and other recreational activities, Bald Eagles don’t seem to be disturbed by human presence. If you are hoping to observe these local treasures, a good rule of thumb is to maintain a distance from the eagles and their nest. If you notice that your presence has them behaving oddly or they seem stressed, back off. Binoculars, telephoto lenses, and Nest Cams set up by the PA Game Commission are excellent tools to observe Bald Eagles from a safe distance.

Despite Bald Eagles being removed from the Endangered Species list in 2007, our concern for their health should not dwindle. Lead poisoning, from ingesting fish with lead weights or lures, or carrion that was shot with lead ammo, can seriously harm or kill eagles. Replacing lead ammunition and fishing gear with bird-safe alternatives is a great personal action to take to protect eagles. 

Due to the health of the local habitat and that our own homes sit adjacent to the river and wild places, we may notice that not only are Bald Eagles nesting along the river, but in our backyards and communities as well! If you notice anything concerning in regards to Bald Eagle nests (the tree the nest is in is falling over, people are deliberately harassing the nests, etc…), please contact your local wildlife services – the PA Game Commission or the NJ Division of Fish & Wildlife.