Saturday, October 16, 2010

Fall banding: Week #9 in review

This week had great days, and very boring days, kind of strange for this time of year. Over five mornings we banded 103 new birds and had 22 recaps -- a higher proportion of recaptures than recent weeks, indicating birds are sticking around a bit. We've recaptured 5 kinglets (both species); typically we only recapture two a season of these wandering sprites.

Warblers are lingering, with four species banded this week: Black-throated Blue (below, putting us at nearly double our usual fall average), Nashville, Orange-crowned, and Common Yellowthroat.
We've only banded a few Yellow-rumped Warblers so far, and really haven't seen a large influx of them yet.

As is typical of this time of year, it's Sparrowpalooza time. Six species of sparrows were banded this week.Field Sparrow.

Fox Sparrow.

White-crowned Sparrow (with young, hatching-year birds like this dominating).

And Song, White-throated, and Dark-eyed Junco.

Hermit Thrushes seem to be around in typical numbers after last year's diminished season total of 27. We've had 30 so far. Due to improved collection techniques, we have obtained seed samples from about 57% of the Catharus thrushes we've handled this year, up from the previous three-year average of around 44%. Already our overall collection of seed samples has revealed different proportions of seed species in the droppings of bird compared to the past few years. Fruit crops can vary from year to year based on weather, pollinator availability, and perhaps "built-in" cycles. Our long-term study of these dynamics will help us understand which species of fruits are consistently important, and which are only used in the absence of others -- important data for habitat management.


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