By Ranger Steve Mueller
January thaw arrives and many birds disappear from feeders. The recent warm spell with a record high temperature of 62 F recently sent a message to the birds. It caused the remaining 4 to 6 inches of snow to melt at Ody Brook. Last to disappear was ice on packed trails.
Some species like the House Finches, Dark-eyed Junco, and the American Tree Sparrow were nowhere to be found. American Goldfinches and Northern Cardinals were seen less frequently. Downy Woodpeckers, Black-capped Chickadees, Tufted Titmice, and White–breasted Nuthatches maintained regular visits. For some reason, Blue Jays and Mourning Doves have been mostly absent for weeks. I saw my first Blue Jay four weeks into the new year. Red-bellied Woodpeckers and Hairy Woodpeckers made irregular feeding stops at suet.
American Crows do not visit the feeders but are seen or heard daily. Pileated Woodpeckers stay deep in mature wooded habitats. Today, a pileated pecked a dead aspen tree causing it to lose a six-foot piece of trunk that fell to the ground. The branched tree top had previously fallen. The remaining erect trunk was riddled today with long vertical drillings. Hopefully the woodpecker found more food energy than it expended searching.
New weather brought seasonal chilling with light snow. Birds normally not seen in the sanctuary provided evidence of presence. Wild turkeys used the trails planned for easy human travel and left tracks in the fresh snow. They are not stupid. They enjoy the ease of unobstructed travel. They stop to scratch in thawed ground and rummage through the blanket of leaves laid last fall where they searched for acorns and other food morsels.
Like turkeys finding food scattered about, birds missing from feeders are out gathering food in locations unknown to me. With the exposure of plants uncovered by the thaw, animals are searching and finding adequate food in the neighborhood landscape. The neighborhood includes natural habitats in the sanctuary of field, upland forest, and floodplain forest with a small farm field included. Surrounding the area are larger farm fields, a cattle farm, and residential home lots.
The birds have choices for food exploration. Some are richer than others. I saw a Black-capped Chickadee working small branches on a tree. It was most likely seeking overwintering insects tucked into crevasses on twigs. The chickadees have searched many of the thousands of goldenrods for insect galls. Many of the galls have been pecked open and the single white grub of the Goldenrod Gall Fly eaten.
The grub resides in the thickened round gall on goldenrod stems and emerges as an adult in spring when new goldenrod shoots are about 3 inches tall. The fly mates and lays an egg on the plant where the hatching larva burrows into the soft young plant tissue and causes irritation. The plant grows a thick ball of tissue around the insect to protect itself. The growth known as gall is what the grub feeds on all summer.
Several species of small blue butterflies overwinter as eggs laid in flower and leaf buds of host food plants specific for their species. You might find Spring Azure eggs in terminal buds of dogwood shrubs, the Silvery Blue’s eggs in vetch and Eastern Tailed Blues in clovers. The bright yellow Clouded Sulphurs spend their winters as small young caterpillars or pupae nestled among legume host plants. Spicebush Swallowtail and Promethea Moth suspend chrysalis or cocoons on or near their Sassafras caterpillar host. Mourning Cloaks and Eastern Commas overwinter as adults in protected seclusion where they might squeeze behind loose bark. If any of these creatures are discovered by searching birds, they likely become a rich protein meal.
It makes sense for the birds to search for these energy rich meals scattered about habitats during milder weather when they are not burning as much energy as they do during near subzero weather. I do not know if they reason this and return to feeders when they need to eat more to maintain adequate energy to survive. What I do know is I help birds survive winter in their nature niches. Their return to feeders brightens and enriches my life.
Natural history questions or topic suggestions can be directed to Ranger Steve (Mueller) at firstname.lastname@example.org – Ody Brook Nature Sanctuary, 13010 Northland Dr. Cedar Springs, MI 49319 or call 616-696-1753.