Mass Audubon has been using citizen generated data (known as "citizen science") to monitor populations of feeder birds in Massachusetts. This year's data has been turned in and analysed by Mass Audubon staff and the results are very interesting. Here is an excerpt of the report posted on their website.
- Bird activity was markedly reduced at feeders this year. Overall numbers reported were down, with all but 3 species on our list (House Sparrow, Black-capped Chickadee, American Goldfinch) less likely to be reported than during Focus on Feeders 2011. This relative absence of feeder birds was most likely caused by the extremely warm temperatures and lack of snowfall we experienced over the winter. It will be interesting to follow this trend in subsequent winters, to see if changes due to climate warming affect activity at feeders in the long run. Most climate models predict that we will experience substantial fluctuations in weather from year to year, and we’ll be watching closely to see how the birds react.
- Despite the notable absence of birds from Massachusetts feeders this winter, species rank order remained similar to past years (i.e., the same species were most commonly reported). One exception was the increase in rank-order for American robin. Again, warm winter temperatures likely allowed many individuals to remain in the Commonwealth for the winter, whereas they’d be inclined to migrate to warmer climes most years. Another exception was a sharp drop in rank-order for blue jay. Blue jays showed the most dramatic declines of all species in general, with approximately one-third fewer participants seeing them at their feeders this year. Massachusetts Christmas Bird Counts also indicate that blue jays are notably scarce this winter, due in part to last fall’s significant shortage of acorns.
- Other notable decreases were in sightings of red-breasted nuthatch, Carolina wren, American tree sparrow, and pine siskin. Note that pine siskin is one of our “irruptive” species, so would be expected to vary greatly from year to year. However, Mass Audubon’s State of the Birds Report indicates that this species is also showing long-term declines in winter, along with American tree sparrow, blue jay, and several other species that we typically think of as "common".
- As noted last year, European starling, one of our non-native species, continues to show a long-term decline in feeder numbers. This species is also experiencing quite dramatic declines within its native range (particularly in the U.K. and Northern Europe), although reasons for these declines are currently unknown. We and other conservation organizations across North America will continue to monitor this species, to help determine what is causing this negative worldwide trend.
For the complete report please visit the Mass Audubon Focus on Feeders website.
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