Stacey Cole's Nature Talks: Assessing 2012 backyard winter bird survey; predictions for 2013
Last week we urged our readers to participate in the 2013 N.H. Audubon state-wide Backyard Winter Bird Survey.
This week, let's turn back to comments on last year's survey by Dr. Pamela Hunt, Audubon's senior conservation biologist, who wrote: "The winter of 2011-12 was noticeably warmer than usual, ranking as the fifth warmest since detailed records began in 1895. On the survey weekend itself, Saturday was marked by above average temperatures, but these dropped significantly overnight with the passage of a cold front, making Sunday one of the coldest days of the entire month. At the same time, it was a relatively dry winter, and most of the precipitation fell in the form of rain. There was limited snow on the ground in the southern half of the state, and even the north snow depths were lower than usual.
"Species hitting record (or near record) highs included the usual suspects: Wild Turkey, Red-bellied and Pileated Woodpeckers, Carolina Wren, Eastern Bluebird, and American Robin. These are all species that have been increasing on the Survey in the past ten years and I see no reason why they won't continue to increase for several more years to come!
"The total of 4,760 American Crows is almost a thousand birds higher than the previous record, and I suspect one or more observers were lucky enough to have a roost nearby. Even more dramatic was the increase in Turkey Vultures, where the previous record was only three. This species has only been recorded 11 times on the Survey, including seven of the last 10 years. Like so many other southern species, it has been expanding its range north, but most still migrate south by November. The fact that 27 were tallied in Rockingham County (the other was in Cheshire) belies both the mild winter and, like the crows, a nearby roost site.
"One more for the record books in 2012 is Bohemian Waxwing. In my last summary I predicted an influx of both this species and Pine Grosbeak in 2012, and seem to have batted 50% on this one. Pine Grosbeaks were scarce everywhere in New England last winter, but Bohemian Waxwings staged a major invasion of Northern New England. Only a handful made it south of the White Mountains in New Hampshire but in Coos and northern Grafton Counties they were quite common through February, and the survey total of 720 is more than three times the previous high.
"I also predicted a general lack of winter finches for 2012, and pretty much nailed this one. Collectively, these birds are called 'irruptives,' meaning that they undertake irregular mass migrations in response to food supplies.
"There were only a handful of redpolls, almost no crossbills, and a modest number of Pine Siskins. Evening Grosbeaks reached their second lowest total ever. As predicted, American Goldfinches did make a good showing, with the third highest total in the last ten years. And then there was our state bird. The total of 991 Purple Finches is unusually high, since most field observers found very few in New Hampshire last winter. Most were in the far north, and numbers south of the mountains were universally in the single digits. It was thus noteworthy that some Survey participants reported multiple Purple Finches but no House Finches in southern counties such as Rockingham and Hillsboro. These two species are difficult to tell apart and House Finch is actually much more comon at feeders in southern New Hampshire (i.e. south of the Lakes Region).
"To wrap up the irruptive discussion, let's talk a little about the Red~breasted Nuthatch. Like many finches these birds rely heavily on spruce cones for winter food and unlike White-breasted Nuthatches they are highly migratory.
"In 2011-12 there were lots of cones to the north and relatively few to the south. Some migratory Red-breasted Nuthatches moved through in early fall of 2011, but they were quite scarce south of the mountains. This is reflected in the Survey total of 396, which was the third lowest ever and about half the long term average."
And now for Dr. Hunt's predictions for 2013: "Although the broader irruptions are often quite predictable, smaller scale patterns are often not, and by mid-December the Purple Finches were all but gone, while crossbills and siskins had become more localized. The clear winners continue to be Pine Grosbeaks and Common Redpolls, which will probably be the dominant irruptive finches on the 2013 Backyard Winter Survey. Numbers of the other species will likely be higher than usual, but not dramatically so, and if the current trend toward disappearance continues they might even be scarce.
"Red-breasted Nuthatches also had a large fall flight, but most seemed to disappear in the late fall. There is a good chance that numbers will be up from last year's low."
It will be a few weeks before the 2013 results are in.
Stacey Cole's address is 529 W. Swanzey Road, Swanzey 03446.