Finch forecast: tracking winter birds

Birders predict which species will visit the Adirondacks this winter based on available food sources

By Joan Collins

In the fall, when most Adirondack breeding birds are migrating south, birders begin to anticipate which species from the north will winter in our area.

Migration, and movements of birds, including “irruptions” of northern wintering species to the south, are all about food sources. While we know which species will arrive in spring to nest, the northern birds that visit in winter are a different mix each year.

Seeds are a primary food staple for many wintering birds, particularly finches. To make predictions about which species we may encounter, an assessment of tree seed crops is taken during late summer. 

Observations are made in the Canadian provinces and across northern states by 50 contributors. Seed crops for coniferous and deciduous trees, including fruit trees, are rated on a scale from zero to 11 (no seeds to a bumper crop).

All the ratings, including the ones I evaluate for northern New York, are sent to Tyler Hoar, a biologist/ecologist in Ontario, Canada. Tyler determines where various northern species might winter based on preferred food sources.

Great seed crops in northern New York won’t necessarily guarantee that northern birds will move south if they have the food they need closer to home. Sometimes, the birds shift east or west within Canada. It’s complicated.

Forecasting finch sightings

Tyler’s analysis, “Winter Finch Forecast,” comes out in late September on the Finch Research Network. It’s published in most Audubon chapter newsletters. This report gives birders a good idea of where to travel to see eight colorful winter finch species and the sought-after Bohemian waxwing.

Adirondack Park tourism gets a wonderful bump in the years that Tyler recommends people head to these parts to see winter birds.

The past three winters can help illuminate how tree seed crops play a role in visiting winter bird species.

The winter of 2021-2022 was an excellent tree seed crop year for white, black and red spruces, hemlock, white cedar, balsam fir, alder, and white and yellow birches. Visitors included red and white-winged crossbills (who nest in winter), purple finches, pine siskins and American goldfinches.

Bohemian waxwings were scarce with excellent fruit sources to the north, and common redpolls had abundant birch, alder and spruce seed crops closer to home.

Shifting food sources

Food sources were quite different in the winter of 2022-2023 with a lack of cone crops in the Adirondacks, so no crossbill species. But a bumper white ash crop resulted in a record irruption of pine and evening grosbeaks. Nearly 200 evening grosbeaks spent six months at our sunflower seed feeders in Long Lake.

Pine grosbeaks and Bohemian waxwings enjoyed the abundant fruit on crab apple, mountain ash and buckthorn trees, albeit in different ways. Bohemian waxwings eat the fruit, while pine grosbeaks make a mess of their bills by squishing berries to get to the seeds inside, discarding the fruit.

This past winter, 2023-2024, there were large irruptions of red crossbills and pine siskins. White pine had an excellent cone crop in the central Adirondacks and a bumper crop on the eastern side of the park that attracted nesting red crossbills. Pine siskins fed on a bumper balsam fir cone crop, white cedar, alder and spruce crops.

‘Hopeful’ birdwatchers

Many other species from the north visit every winter, and some rarely, such as great gray and northern hawk owls. When small mammal prey such as voles and mice are in limited numbers in the northern boreal forest, and when we have such prey here, these owls thrill birders with their presence. Mice are abundant this year, so I’m hopeful.

The tree seed crop for our coming 2024-2025 winter shows food for nearly every irruptive species. Red spruce and hemlock have bumper cone crops. Red crossbills began nesting in late summer and they will follow with another nesting in the heart of the winter (their usual pattern). White-winged crossbills will also nest in late summer which often foretells of a larger winter irruption, but I have not encountered any this summer.

There is fruit for Bohemian waxwings and pine grosbeaks; ash tree seeds for evening grosbeaks; white and yellow birch seeds and alder seeds for common redpolls and pine siskins.

It’s a potentially exciting time to find northern species wintering in the Adirondacks. The “Winter Finch Forecast 2024-2025” will shed light on food sources to our north and the complex puzzle in predicting bird movements.