November 30, 2020
This was a last ditch attempt to see a few late fall birds that sometimes pass through along the lake. They are undependable and even if seen are not always easy to identify. They include the Cave Swallow, the Gyrfalcon, the Horned Lark and jaegers (gull-type birds) that only show up on strong east winds. I didn’t get any of these species while I stood here on top of a sand dune. Now, in December, the water between the dunes is usually frozen, so even the geese and ducks have left it. The only birds left seem to be the usual gulls, Canada Geese and Mallards in the channel. So, the birders are left to inspect the few pines and spruces in Lake County.
This is the year of an irruption!! Not volcanes- finches! In some years the food sources in the northern territories of the US and Canada do not produce sufficient cones, nuts and fruit to support the birds that depend on them. These species, mainly finches and grosbeaks, are forced to look elsewhere for food. That means they move much further south than they ordinarily would. This movement is called an irruption, as a large number of birds are suddenly moving out of their usual range. Many times they occur in flocks.
In lake County, spruces and pines are not native species. Fortunately the Forest Preserve District has several locations that have preserved these trees that were originally planted in tree farms. Lyons Woods has spruce and a small number of pines. Van Patten Woods, north and west of here, has a nice stand of pines and a bonus stand of Alders. The campground at Illinois Beach State Park also has pines.
All of the species involved in this irruption are picky eaters. The Red Crossbills chooses cones of pine trees. The White-winged Crossbills prefer the cones of spruces. The Redpolls go for the very tiny cones of Alder trees. They can’t help being picky- the bill of each species has evolved to be most efficient at pulling seeds from specific types of cones. In fact, the Crossbills have evolved to feed from specific species of pine trees and spruce trees. And yes, the bills of the crossbills do cross! I’ll see if I can find a photo. The birds are at the tops of very tall trees, where the cones are, so getting photos is tricky!
The White-winged Crossbills prefer spruce cones. They are more numerous at Lyons Woods. The birds move in flocks and often do not stay in a tree for long. Sometimes the only way to know they are in the area is to hear their calls. That was the case in Lyons Woods for me- no photo but a positive identification due to the nature of their calls.
We had one more irruptive species to locate. This bird, the Evening Grosbeak, does not go to a specific tree and therefore it was much harder to track down. However, the bird likes feeders. Some birders who had visiting Evening Grosbeaks were kind enough to let others into their yards to wait for the Grosbeaks to come in. We finally saw one at a feeder on the northeast side of Bowen Park. It was just a glimpse but enough for a County life bird.
