Fifty years ago this morning, May 15, 1975, at almost this exact minute, my former wife and I captured a male Baltimore Oriole in a mist net. The bird was captured in a regenerating quaking aspen clear cut in an area called locally the "Mikana Swamp". This heavily forested area, is about 6 miles northeast of Rice Lake in Barron County, Wisconsin. Managed for recreation and for forest production, the Mikana Swamp is a diverse mixture of upland deciduous forest pock-marked with numerous small lakes and wetlands created during glacial epochs.
The area where we caught the Baltimore Oriole had been subjected to a clear cut of about 40 acres three years earlier. My uncle and I had been hired by the Wisconsin Department of Natural Resources forester to do timber stand improvement in the clear cut. This was a fancy name for walking among the stumps of the clear cut and felling any trees or saplings that the forest cutting operation missed. It was a great way to earn money for college.
Fifty years ago this morning the quaking aspen were regenerating quickly with most of the saplings about 7 feet tall. We had cleared lanes in the saplings to set up mist nets to capture and band birds
Despite the general negative connotation that some clear cuts receive, the one we were netting in was dripping with migrant birds. In five years netting birds in this clear cut we captured and banded 77 bird species during spring and fall migration. One year we banded the most Golden-winged Warblers (9) of anyone in North America from this clear cut.
After capturing the Baltimore Oriole we removed it from the net, measured it, weighed it, checked its body for fat deposition, and released it.
Baltimore Oriole spends the winter from the southern United States to as far south as northern South America. I once found one in late May in the British Virgin Islands in the West Indies. Baltimore Oriole nest well north into Canada and is a commonly heard and occasionally seen nesting bird in my part of northern Wisconsin. The bird we banded very easily could have been dining on insects in a mangrove forest near Barranquilla, Colombia, a week ago and now it was in my hands in northern Wisconsin. A week later it could have been building a nest with a mate in central Ontario, or it could have been 10 miles north of the Mikana Swamp nesting in someone's yard. We never knew because this was the only time we saw the bird that year.
Fast forward one year to May 16, 1976. My former wife and I are tending mist nets in the same clear cut area. At about the same time as a year earlier (8:00 a.m.) we removed the same male Baltimore Oriole from the same net in the same location and even in the same panel of the net we had captured the same bird in one year and one day earlier! Again we measured the bird, weighed it, checked for body fat (he needed Ozempic). This was the only time we saw the bird in 1976.
Lightning struck a third time when on May 15, 1977, at almost the same minute, in the same panel of the same mist net in the same location as the two previous years, we captured the same male Baltimore Oriole again. We followed the same procedures as the two previous years, checked the band for wear, and released it never to see it again.
Site tenacity in birds is well known and well-established in ornithological circles. This is especially true when birds return to wintering areas or to nesting areas. It is also known among migrants. I remain amazed that this bird, with a brain the size of a pea, could navigate across the northern hemisphere at least three different occasions, only to return to the exact spot at the same height above ground on essentially the same day three years in a row.
In December 1974, we captured a male Dark-eyed Junco at a bird feeder maintained by Tom "Mad Dog" Nelson at his home about 5 miles northeast of River Falls, St. Croix County, Wisconsin. We banded the Junco and released it. We ultimately recaptured the bird several times at Tom's feeder that winter plus in the winter's of 1975, 1976, and 1977. Dark-eyed Junco nests from northern Wisconsin well into Canada, yet this bird was able to find the same feeder in the same rural area of Wisconsin at least 4 years in a row.
In March 1985, my field assistant Paul Sievert (now at the Cooperative Fish and Wildlife Research Unit at the University of Massachusetts) captured and banded a male Kirtland's Warbler near Governor's Harbour on the Bahamian island of Eleuthera. In addition to a US Fish and Wildlife Service aluminum band, Paul attached three colored bands in a unique combination to facilitate identification in the field should the bird be found again. The original banding location was a 4 acre patch of a common shrub Lantana involucurata (sorry I never learned the common name). Resorting to anthropomorphism, we named the bird "The Governor" because of where he had been captured.
There were maybe 500 Kirtland's Warblers remaining on earth when I started working with them in 1984. They were critically endangered. There are now more than 3000 breeding pairs and the species is no longer endangered. I had nothing to do with the turn around but a 40 acre controlled burn that got out of control and rejuvenated 800 acres of Jack Pine in northern lower Michigan did.
In June, 1985, we refound the Governor in a patch of Jack Pine forest east of Grayling, Michigan. He was mated with a female and together they produced 5 hatchlings that eventually fledged. December 1985 through March 1986 we found the Governor almost daily in the same 4-acre patch of Lantana where it had been banded and color marked a year earlier. During the summer of 1986 we regularly found the Governor and his mate on the same territory in the same Jack Pine forest east of Grayling, Michigan.
Wash, rinse, repeat, the Governor was refound in late 1986 in the same patch of Lantana on Eleuthera where it had been banded and color-marked in March 1985. And completing the cycle the Governor was found again mated on the same territory near Grayling, Michigan in June 1987. Again with five young in its nest.
All of this migration over thousands of miles, sometimes over featureless open ocean (especially the case of Kirtland's Warbler wintering in the Bahamas, Turks and Caicos Islands and northern Dominican Republic) is one of the reasons I have been fascinated by birds since I identified my first species by myself (a Northern Bobwhite) when I was 4 years old.
Birds migrate by a combination of geomagnetism, familiarity with landscape features, and if they are night migrants they also orient on stars and constellations. Its the same with salmon who after spending several years in the ocean return not only to the river or stream of their birth but to the same stretch of the river or stream where they hatched. Salmon do it by knowing the "taste" of the water from the river or stream where they hatched. For birds its also instinctual and they do it with a brain much smaller than the brain of the humans who are destroying the places birds depend on throughout their life cycle.
Birds are truly amazing critters.
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