Varied Thrush in Central Park, Nov 30th

It's just a number, but as of last weekend I'd been sitting at 194 species seen in Central Park for quite some time. Now that I'm no longer in Manhattan it's become a little harder to track down one-day wonders although over the years I've not done badly in that department. I did, however, take time to visit the park on Tuesday morning to see the Varied Thrush that had originally been spotted by Mike Bryant et al on Sunday.

This Varied Thrush is an immature, and so sex is indeterminate, and there's some indication that it's had a hard life - the feathers at the throat on one side show a cleft that is suggestive of some injury. And it was mentioned to me that a toe might be dislocated. I didn't notice this myself and the bird seemed quite mobile and robust. In fact the only other Varied Thrush I'd ever seen was in MA in the dead of winter at Quabbin Reservoir feeding in the snow (Feb 13th 2004). I'm grateful that this bird stayed around long enough to be park bird #195.

Now all we need is another 5 vagrants.....

Sapsucker-assisted vagrancy

In the late half of this winter we've seen two noteworthy NYC vagrants - the Union Square Scott's Oriole and the Central Park Western Tanager - help their survival prospects by taking advantage of a less conventional food source of plant sap. Both the Oriole and Tanager have been seen drinking from sapsucker holes. Both of these sites happened to be on Viburnam bushes - an exotic hardy evergreen shrub that is present on both of these city parks. Later in the winter the Scott's Oriole was re-found in Thompkins Square Park doing exactly the same thing - drinking sap from Sapsucker holes in Viburnam.

Last winter an almost-overwintering Cape May Warbler in Riverside Park in Manhattan was seen drinking sap from Sapsucker holes, although these were probably from more native trees than Viburnam shrubs. Exploitation of sapsucker holes by Cape Mays is not an uncommon thing to observe in the Pinetum region of Central Park in late fall or early winter.

Shai Mitra, via the NYSBirds-L list made the observation that the numbers of overwintering Yellow-bellied Sapsuckers have been greater in recent years. Unfortunately I can't locate a reference for that observation. The BNA account for this species illustrates that it has a wide wintering range, with NYC being at the extreme north-eastern edge of it. It remains to be seen what influence non-native plants have on this range, because the Sapsucker doesn't appear to be all that picky over which plant to use. So a lot of unanswered questions. Certainly vagrants aren't obliged to exploit Sapsuckers - the 2006/7 Western Tanager in NJ was eating Juniper berries - but perhaps it indicates that the vagrants or out-of-seasonal rarities that we observe are the ones that are most resourceful in exploiting local food sources. Memorably the Scott's Oriole may have chosen to hang around the small corner of Union Square Park because the fruit offerings at the Ghandi statue offered it a supply of palatable food - it's a nectar drinker during the summer but eats fruit on the wintering grounds in Mexico.