by Carl Runge
Photo by Jeff Hullstrung
The Green Mountain Audubon Society has been surveying birds at the Catamount Community Forest since 1996. With variable habitats which include forests, grasslands, edges, power line ROWs, and wetlands, we have identified 140 bird species with evidence for breeding at Catamount for 53 species. One bird we have been watching closely is the Bobolink, a grassland species which has been in serious decline in the U.S. This wonderful member of the blackbird family is a long distance traveler. It winters in Argentina, Bolivia and Uruguay and travels all the way to the northern U.S. and southern Canada to breed. With such a long distance to travel, Bobolinks get a single shot each year to successfully nest and raise their young. If the first attempt at nesting is unsuccessful, it’s back to South America.
The preferred nesting habitat for Bobolinks is grasslands, particularly hayfields. The problem is, when the hayfields are mowed in June or July, the nests are destroyed. At Catamount, we have had an historical Bobolink nesting field on the east side of the property. Since the Catamount fields have been leased to a farmer for haying the past five years, Bobolink nesting has been thwarted. After the town acquired Catamount, it was able to negotiate with the farmer a mowing schedule that was favorable to nesting Bobolinks. This year the lease allowed the farmer to hay early the other fields at Catamount which do not attract Bobolinks, but restricted mowing on the east field until August.
Good news to report, the strategy has been successful! On May 13, right on time, we were welcomed by the “R2D2”-like call of the returning Bobolinks. On that day we spotted on the east field, 5 males, preceding the females. The next week we saw the first females, and shortly after that both species could be seen popping up and down from potential nest sites. On June 15 we observed a male carrying a caterpillar, likely food for a recently born chick, and this observation continued over the next couple of weeks.
In early July, we had a scare. Following a brief but powerful thunderstorm which flattened the field, the population appeared to have disappeared. On July 3, we saw no Bobolinks, and we were concerned the storm may have destroyed the nests. Not to worry, by July 9 they were back. On that day we saw large numbers, at least 30 Bobolinks. There appeared to be 2 family flocks numbering 10 to 12, with adult males and females, and several fledglings, which are difficult to tell apart from the adult females. There were similar findings on July 16 with the fledglings now very independent. Then, by July 22, all were gone from their nesting field. This was confirmed on July 29, and shortly after that we released the field to the farmer who mowed it a few days later. We speculate that all the Bobolinks had retired to an undisclosed location to molt and re-grow new feathers, prior to the time in the fall when they get together in large flocks and return to their wintering grounds.
One interesting observation is that the Bobolinks did not appear to be disturbed by the bikers and runners who used the trails around the perimeter of the field. It is also encouraging that, despite several years of unsuccessful nesting at Catamount, the birds continued to return to their ancestral breeding area. We are hopeful that as long as we continue the current management plan, our breeding population of Bobolinks will continue to grow and flourish at Catamount.