BEAN STATION – Kingswood residents learned about the Double-crested Cormorant (sometimes referred to as a “water turkey” or “snake bird”) and its colonization of Bird Island on Cherokee Lake during a presentation by TVA Lands, Plans & Management, Saturday, June 26.
The event was held at the Bean Station home of Jeff, Ashley and Kristina Taylor and was sponsored by the Taylor Law Firm. The presentation was held as part of Kristina’s eighth grade service project at Episcopal School of Knoxville. About 20 residents of Kingswood Home for Children were in attendance.
TVA biologist Raymond Moore spoke about TVA’s history, and its research of the Double-crested Cormorant. He said TVA had conducted research on islands being impacted by the birds in Guntersville, Alabama in about 2006. He talked about resource degradation caused by the birds.
“These birds impact trees on islands,” Moore said.
“What we found out was… these birds are gregarious, they’re colonial nesters,” he said. “They get together in large numbers and they can cause some really, really heavy damage to the vegetation on these islands.”
He said large numbers of the birds can change the diversity of the flora and fauna on islands they inhabit by altering the pH of the soil. Cormorant guano is very acidic due to the birds’ diet, which is almost exclusively fish. It is this acidity that, over time, alters the pH of the soil where the birds nest.
The birds nest in trees until all the trees die. This eventually causes other varieties of birds inhabiting the islands to leave. The Double-crested Cormorants may move on once all of the trees have died, but Moore said a lack of predators on islands sometimes leads to the birds beginning to nest on the ground once the trees have died.
Moore said poke weed and poison ivy were two of the most dominant plants surviving on TVA-researched islands after the Double-crested Cormorants left. He said the population of birds on Bird Island in Cherokee Lake isn’t large, but is growing.
Moore said despite the negative effects to the flora and fauna on islands, the birds do not have an impact on overall water quality in the lake.
After being treated to a meal of sandwiches and fresh summer side dishes, guests boarded a number of boats for an excursion to Bird Island to observe the Double-crested Cormorants in their habitat. Once at Bird Island, Moore continued to provide information about the birds and answered a number of questions.
After returning to the Taylors’ home, guests were treated to a bonfire and s’mores.