It’s hardly fair that although we have had two hard-working and dedicated volunteers surveying the food plot weekly since August, Mark and I spotted the rarest bird yet during the first week we took over the survey. Rare, not just for the food plot, not just for Goose Pond, but for all of Wisconsin.
Walking the trails of the food plot through deep snow on February 1st, Mark and I noticed an unusual calm. Normally the ground is piping with American tree sparrows and dark-eyed juncos, and the stalks of sorghum and sunflowers are swaying with more sparrows and American goldfinches, but this time all was still, and I spotted only a mourning dove resting on the ground. As we looked around, we noticed, what we thought at first was a kestrel resting on a telephone pole. “Not a kestrel, but maybe a sharp-shin?” I asked Mark. “No, not a sharp-shin…” Mark knew what it was, but he was quizzing me, and I willed my field glasses to reveal more and hoped the bird would not fly. It sat so still, and never bobbed its tail, and I soon realized it couldn’t be a kestrel. Smaller and darker than a sharp-shinned hawk, but larger and stockier than a kestrel, it eventually dawned on me that here was a merlin. When it finally did take off, it flew with a faster, heavier stroke than a kestrel. Since that sighting I’ve been convinced that every dark, swift profile I see in flight is another merlin.
It is unlikely that Mark, or I, or other visitors to Goose Pond will see another merlin this season, and that’s because merlins, according to Sam Robbins in his Wisconsin Birdlife: Populations & Distribution Past & Present, “don’t belong in Wisconsin in winter” (1991). Where they do belong is west as far as California, and south throughout the southern United States and into Latin America as far as Ecuador, yet Robbins notes that at least 30 times from the 1960s-1990s merlins have been seen in Wisconsin in late January and February. Though still rare, they are more commonly seen along the shores of the Great Lakes, during fall and spring migration when they pass through en route to their summer breeding grounds in the boreal forests of Canada and far northern Wisconsin. The sub-species that is seen in Wisconsin is the taiga, or boreal merlin, in contrast to the prairie merlin of the southwest, and the black, or Pacific merlin, of the northwest.
Merlins were in steep decline throughout the middle of the last century, but populations in Wisconsin appear to be increasing as forests in the north regenerate, and as DDT and other pesticides become less prevalent environmental contaminants. Other theories on their increasing populations relate to the expansion of human settlements; with more development comes more edge habitat, and an increase in populations of edge-loving birds that serve as prey for merlins. Also, with more development, urban adapted species, such as crows, increase and create nests that can be used by these non-nest building falcons. The Wisconsin Breeding Bird Atlas II project, now entering its third year, has shown that nesting merlins are increasing in the north, and expanding into north-central Wisconsin. There have even been confirmed nesting merlins as far south as Waupun and Milwaukee.
Goose Pond Sanctuary is neither urban, nor boreal, nor located particularly near the Great Lakes, yet on eight occasions in the past, merlins have been confirmed here. The first recorded sighting on eBird was also in winter, on January 24, 2001 by Aaron Stutz. The highest recorded number at Goose Pond was two merlins spotted by Kyle Hudick on October 12, 2013. Other sightings have been confirmed in March during the spring migration. They might be attracted by the openness of the sanctuary, or by the abundance of small birds, particularly in the food plots, but more likely merlins are just passing through on their way to more suitable habitat, leaving scarcely a trace beyond the little thrill it gives to those lucky enough to spot one.
Written by Maddie Dumas, Goose Pond Land Steward