Why these birds are invading feeders in eastern Idaho

“Are you getting a lot of Evening grosbeaks at your feeders?” asked Todd Moseley of Rexburg while we were watching a track meet a week ago. “I usually have a couple come in for a few days, but they have been here for a couple of weeks and they are emptying my black sunflower seed feeders daily.”

I had a couple of males show up three weeks ago and the flock of these beautiful seed eating machines has steadily grown to about 30. At times, they become so loud that I am missing my outside mid-morning naps because of all the chirping going on.

With them, other species have migrated into southeastern Idaho, including Cassin’s finch, American goldfinch, Pine siskins, a few Lesser goldfinch and even a single Rose-breasted grosbeak have showed up. The common Black-headed grosbeaks has not showed up yet, but they will be here soon.

The Evening Grosbeaks, one of the largest of the finch family, has been consuming sunflower seeds as fast as they could shell them. Hulls of the seeds seemed to be flying as fast as an old threshing machine spewing out chaff when I was a kid. It has become an expensive hobby shelling out funds to feed these ravenous birds as they empty my feeders daily.

I left the feeders empty for a day to see what would happen and they gathered in the tops of the trees, calling louder. It seemed like they were begging for food like hungry children.

Another bird-feeder in my neighborhood said he does not have very many because he does not feed them black sunflower seeds. I have had to stop feeding the bird seed mixture that contains millet as the grosbeaks scoop out the other seeds looking for the oil rich sunflower seeds.

It may not seem like it right now, but the Evening Grosbeak population has been declining drastically for the last 40 years. In 1968 the estimated population was 17 million. It dropped to 3.8 million in 2008 for a 78-percent decline. Most of the decline is happening in the eastern part of the US and Canada, while populations in the Rocky Mountains remain stable. Once abundant in Quebec, these striking birds have virtually disappeared.

The National Audubon Society has listed the Evening Grosbeak second on their list of “Common Birds in Decline.” Habitat loss and acid rain are believed to be the most contributing factors of their decline.

These secretive breeding birds are extremely nomadic during the winter months. In the East they will migrate south, while in the Rocky Mountains they are altitudinal migrants moving short distances in search for food. The warmer winters in the west and severe ones in the east this year may contribute to the lack of birds recorded this winter.

Along the South Fork and Henry’s Fork of the Snake River, these grosbeaks are year around residents but are rarely seen in the thickets along the flowing water. The South Menan Butte is a popular place to find them in the winter.

Sometimes called the “English Parrot” because of its color, big beak and feeding habits, they consume large amounts of food. During the summer, their food consists of conifer seeds and spruce budworms. The abundance of spruce budworms appears to be a major factor in their migration and nomadic appearances.
During the winter, Evening Grosbeaks will be found where fruit, berry and mature evergreens are located. Box Elder trees and Hawthorn bushes are some of their favorites to visit. These opportunistic eaters will consume large amounts of sunflower seeds when feeders are found near mature trees. A single Evening Grosbeak was once recorded eating 96 sunflower seeds in five minutes. Someone was bored.

If you have them in your yard, enjoy them because they will soon move to the mountains and forests for the summer. If you don’t have them and want them, fill you feeders with sunflower seeds. If you want to get rid of them, stop filling you feeders with their popular food for several days.

I will continue to feed them because Ace Hardware needs me to support them. I can nap somewhere else if I need to.