Sunday, September 20, 2015

The Biggest Bird on the Beach

If you are from the Oregon Coast, you know that bald eagles are seen in great abundance along the shore. But this hasn’t always been the case. In the past, bald eagles had such low population numbers that they were put on the endangered species list. Before 1972, DDT was a popular pesticide that was used all over the country. In coastal areas, the chemicals in this pesticide would end up in the ocean, building up in fish populations that eagles and other large raptors would then prey upon. The chemicals used in DDT would soften eggshells, making bald eagle reproduction success rate very low. Once the use of these chemicals was banned in the United States, eagle numbers began to rise and they were eventually switched from the endangered species to threatened species. It wasn’t until 2007 that eagle numbers were high enough to remove the bird from both endangered species and threatened species lists.  

Nowadays, with such a large abundance of seabirds, like those seen at Haystack Rock, it’d be surprising if eagles weren’t spotted along the Oregon Coast.  Bald Eagles are a rather large predator, which prey on fish, birds and rodents. Due to their size, they do not have many predators other than those that invade their nests and snack on their eggs. This may include raccoons and other rodents and birds.

Some birds may harass eagles when the eagle is going after individuals of their species. At Haystack Rock, Western Gulls are normally seen pestering the eagles on the hunt. In Cannon Beach, there is an eagle nest in a patch of trees directly across the beach from Haystack Rock. There is also a pair on the north end of Cannon Beach, which prey on the abundance of birds seen on the rocks at Chapman Point. When the eagle arrives at these rocks, it is no secret. There are some very distinct sights and sounds that warn all about the eagles’ presence.
Juvenile Eagle holding Common Murre being pestered by Gulls
Photo Courtesy of Alanna Kieffer 

Juvenile Bald Eagle with Common Murre in talons being chased off by a Western Gull
Photo Courtesy of Alanna Kieffer


Gulls use a loud warning call to signal all the other gulls on the rock to be ready for the predator. Common Murres will abandon their spot on the rock to head out to the water where they are more protected. Cormorants will mostly stay seated; the eagles don’t normally mess with them due to their large and strong beaks. Puffins hide in their burrows and western gulls join the fight. Some dive bomb the eagle while others hover around trying to distract or confuse the eagle. With a wingspan of about 6 feet, it is easy to spot the eagle in the mass of birds.

Bald Eagle posted at Chapman Point
Photo Courtesy of Alanna Kieffer



At Haystack Rock the most common bird seen taken by the bald eagles are Common Murres. Just about every year around the beginning of summer the eagles mate and have a chick. When the chick first hatches, the adults are heavy on the hunt for food to feed their chick.  Once the chick is old enough to hunt, the juvenile will head over and learn the ways of hunting at the rock.

Eagle after an unsuccessful hunt at the rocks
Photo Courtesy of Alanna Kieffer
Bald eagles can be seen at Haystack Rock all year round, but the beginning of summer is a prime time to see some eagle action! Like most nature, you may never know exactly when the eagle is going to strike but the gulls will definitely let you know. Next time you’re at the rock and the birds start to get noisy, remember to look for the Oregon Coasts largest bird of prey, the bald eagle!


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