They’re America’s national bird and a symbol of the nation.
Bald eagles are majestic creatures with their distinctive white heads, yellow beaks, and brown bodies. Their wingspans can range between five and seven feet.
Decades of toxic waste dumping into the ocean off of Southern California led to the disappearance of the birds from the Channel Islands in the mid-20th century.
But, they’ve made an amazing comeback.
"The eagle population is doing great across the Channel Islands," said Annie Little, who is the Supervisory Natural Resource Manager with Channel Islands National Park. "This season was very successful. There were a total of 23 breeding pairs across the islands, and there were at least 23 successful fledgelings.'
The problems started in the 1930s, when companies began dumping toxic materials into the ocean off the Southern California coastline.
Among the pollutants was the now widely banned chemical DDT. It got into the marine food chain. Bald Eagles would eat fish contaminated with DDT. It caused the shells of the eggs they laid to be so thin that they would break in the nest when the parents warmed them.
"Bald eagles disappeared from the Channel Islands by the 1950s," said Little. "They were impacted by DDT, which ended up throughout the marine environment. Bald eagles, being at the top of the food chain, experienced a widespread impact."
The bald eagle population was dying off. Little said biologists realized they needed to do something. The Institute for Wildlife Studies, Channel Islands National Park, and other groups began recovery efforts.
"It's been a long, sustained process," said Little. "The first efforts were made by David Garcelon of the Institute for Wildlife Studies back in 1980. After several decades of that work, and continued issues with eggshell thinning, a second major effort was started in 2002, releasing bald eagles on Santa Cruz Island."
She talked about the strategies used to restore the bald eagle population on the islands.
"There was an intensive captive breeding program at the San Francisco Zoo," said Little. "We also had a program bringing wild chicks down from Alaska and British Columbia, and slowly reintroducing birds back into the wild."
The population grew to the point that by 2006, researchers were able to step back and let it expand naturally.
"Right now, we've recorded eagles breeding on six of the Channel Islands," said Erin Weiner, a lead researcher for the Institute For Wildlife Studies Eagle Project. This is the first year we've observed breeding eagles on San Miguel Island, so that was exciting...a big milestone."
"We know that, based on natural history records from before the 1950's, eagles did nest on all eight of the Channel Islands, at least one pair. So, I think it's a matter of time. I would hope to see them reestablish there (on all of the islands) someday."
So far, there are no birds reported to be nesting on San Nicholas or Santa Barbara Islands.
Efforts continue to support, monitor, and study the island's bald eagle population.
"I do a lot of foot surveys, we have live streams, we have cameras on some of these nests to help aid us in collection of data," said Weiner. "In the past, we've also banded birds to learn more about their survival and their movements. The program has been going for 45 years, so we've amassed such a dataset we're trying to use that data we've collected to ask questions related to future management."
They recently experienced a setback: The nearly 19,000-acre wildfire on Santa Rosa Island in May claimed the life of one of the young eagle chicks.
"We did have a nest which was located in the Torrey Pines, and unfortunately, that chick was found deceased," said the National Park Service's Annie Little. She added that the birds' overall comeback is amazing.
You can share in the amazement. The researchers' webcam network is available to the public.
Researchers call the growth of the Channel Islands bald eagle population a major conservation achievement. They call it an example of what can be done to help recover an endangered species.
