Eagles, Osprey and Vultures: The Big Birds of Lake Estes
Spring has officially arrived. The confirmation came when the small song birds started to arrive about a week ago. That meant the bugs were back, their main source of food.
But the arrival of spring also brought with it the larger birds, and Lake Estes has several that will spend the summer soaring high above the choppy waters and surrounding ridges.
The bald eagles live here year-round but the osprey and turkey vultures arrived about the same time as the song birds.
As I walk around the lake and make notes about the natural happenings within our District, I find many people asking me what they are seeing.
“Is that an eagle?” is the first thought most people have when they see a big, dark bird flying above the lake.
During the winter, there were two resident bald eagles. One hasn’t been seen in more than a month. Could she be sitting on a nearby nest? Did she migrate farther north? No way to know.
But with more than a dozen turkey vultures and at least two ospreys, the likelihood of the big, dark bird being an eagle is less likely. So how do you know?
Of these three birds, the adult bald eagle is the only one with a solid white head and yellow, hooked bill. Its body is solid brown on the top and bottom, and tail feathers are white, shaped in a fan when flying. The eagle is also the largest of the three birds with a wingspan of 72-96 inches. A bald eagle will fly on flat, straight, outstretched wings. Although all three birds may soar on thermals, the eagle will give several deep wing beats intermixed on long glides. Eagles prefer to eat fish, and may often be seen stealing fish from their neighbor the osprey, but eagles will also eat carrion and small mammals such as rabbits and ground squirrels.
Unique for its diet of primarily fresh fish, the osprey is the smallest of these three big birds. With a wingspan of 54-72 inches, they can soar high above the lake to look for fish and then dive into the water with amazing accuracy to snatch the fish. Although the osprey is also brown and white like the adult bald eagle, this bird has some distinct markings to differentiate it. Its small head has a white crown with a dark, brown eye stripe and dark, hooked bill. Its underparts are white, and when flying, the dark brown and white stripes can be seen on the wings and tail. The wings also have a distinct angle to them when soaring.
These birds, sometimes referred to as buzzards, are considered one of those animals that only a mother could love. Their uniqueness is their featherless red head, one of several features that make this species ideally suited for feeding on carrion. A lack of feathers helps to keep the head clean as they feed inside the body of an animal carcass. The other beneficial features for this scavenger are a highly acute sense of smell to find decaying meat and a sophisticated immune system to protect them from diseases they may encounter in dead animals. Although this sounds repulsive, vultures are very beneficial for an environment because they help keep it clean.
Another easy way to differentiate a vulture from an eagle or osprey is their unique flight pattern; they circle on thermals with their wings in a shallow V. Vultures also are the only bird of these three with a solid black body and contrasting dark gray flight feathers, seen along the edges of the wings in flight. Because vultures do not flap their wings very much in flight, they wait for the air to warm so they can ride the thermals. As a result, you can often see them lounging with wings outstretched in the morning sun.
Where to Find the Big Birds
Each bird seems to have their own favorite perches around Lake Estes, but their territories overlap when it comes to eating, and thus the reason all three are spotted around the lake.
The bald eagle will sit high on top of the power line towers along U.S. Highway 36/North St. Vrain Avenue. When they are hunting or eating, you may find the eagle on the dead tree snags by Fisherman’s Nook parking lot or on the telephone poles by the Lake Estes Marina.
The turkey vultures also like the power line towers but will sit lower in large groups. They also enjoy sitting on the rocks at Cherokee Draw. Often you can find them with outstretched wings enjoying the sun or circling high above the lake on the thermals.
The osprey has started to build a residence on the osprey platform tower near the Estes Park Power Plant. At the west end of Lake Estes near the intersection of Colorado Highway 7 and U.S. Highway 36. When the osprey is hunting, he will fly along the length of the Big Thompson River or circle above Lake Estes. Osprey only like to eat fresh fish so he will immediately fly back to a perch, such as this platform, to eat the meal.
The challenges these birds face living with each other relate to food. Eagles and vultures are scavengers so they may both feed on the same meal. Osprey and eagles both enjoy fish so the eagles often steal fish from the osprey.
Seems the osprey, the smallest of our big birds, has the biggest challenges for making Estes Park its home.