Got out into the forest yesterday (April 6) and the end of a long cold winter is finally here. I had not walked in the forest for a couple of months so I was out just to enjoy the "spring like" conditions (48f with a brisk breeze; snow and ice remaining where ever it has shelter from the sun). Happily, as often happens, I noticed two interesting things during this stroll.
The first was watching Robins feeding on the berries of Oriental Bittersweet. If you've read any of my other posts you know that Oriental Bittersweet has had visible effects on the forest in these here parts and during yesterday's walk I saw an effect I had not previously considered. As I walked I was checking birds to see what species were about on an early spring day and I notice that a group of American Robins were feeding on Oriental Bittersweet berries.
Robins' eating berries is hardly news. My Peterson Eastern Birds guide even notes this as a common "winter" behavior. But, the thing is, Robins were prominently present in Saratoga Springs throughout the winter this year and it was a very tough winter. I saw Robins near my house all winter long and, for much of the winter, a group of 10 or so roosted a large Yew bush just outside my back door. The bush had acquired a canopy of ice and snow which apparently provided some shelter from the wind and cold. I also saw Robins outside my office window (on the other side of town) throughout the winter; usually in a cluster of ornamental crab apple trees.
My Perterson Guides (one from the 50s and a 4th Edition published in 1980) both show Saratoga Springs as outside of the Robin winter range (though only by 100 miles or so). So the question is; does the presence of overwintering Robins represent an extension of their winter range or is it more a case the representation seen in these books being off by what at the scale of the maps is is small amount? The bonus question is, assuming that Robins are extending their winter range, what role are non-native plant species playing in this development? Oriental Bittersweet is present in significant quantities throughout the city as are other non-native trees and shrubs (ornamentals) that bear fruits and berries. Have these human alterations allowed the Robin to extend its' winter range by providing additional food sources? This is a specific example of the larger questions I have about the role humans are playing in altering ecological communities at regional scales.
Flooded hardwood forest area at the south end of the Hemlock Forest; April 6th, 2014
The second "interesting" thing I noted was related to my absolute favorite species present in the Hemlock Forest. As I walked into the woods I wondered if Deer Ticks (Black Legged Ticks) would be active at this point in early spring. I commonly take precautions against ticks such as spraying my pants with tick repellent but I left the house without thinking about ticks. This seemed safe if only because the grasses and plants where they tend to wait for potential meals are mostly still frozen or semi-frozen. However, habits being what they are I periodically checked my clothes for unwanted guests. Nearing the end of the walk I noticed a small black spot on my pant leg. Thinking that it was probably dirt I picked it off and lo and behold it started scurrying across my finger tip. Spring is really here. The Deer Ticks are on the prowl.
