State College Bird Club

23 Sept. 2009

The State College Bird Club met at Foxdale Village on 23 Sept. 2009.  Twenty-seven members and guests attended; Deb Grove presided.


Nan Butkovich read the minutes.  Dorothy Bordner read the treasurer's report and checklist.  Attendees reported  ___  species within a 25-mile radius of Old Main since 1 Sept. 2009.  Species of note included Olive-sided Flycatcher, Yellow-bellied Flycatcher, Philadelphia Vireo, Marsh Wren, and American Avocet.


•    The observing platform at Julian Wetlands is out.  The labor source that was planned on didn’t pan out.  

Upcoming events

•    28 Oct.:  Don Dearborn will be our next speaker.
•    4 Oct.:  Bird Club will have a table at Clearwater Conservancy’s annual Spring Creek Day at Millbrook Marsh.  
•    13 Oct.  The Big Sit…  We have two local circles.  Trudy and Dave Kyler have one at the hawk watch on Stone Mountain, and Diane Bierly and Bob Snyder have one at the beach at Bald Eagle S.P.


Sara Parbian, a graduate student at Penn State, spoke on “Snails for Dinner?  Effects of Calcium Availability on Forest Songbirds.”  While large birds are able to store calcium in their long leg bones, small birds cannot.  They must supplement their calcium intake in order to produce strong egg shells, and the extra calcium must be consumed roughly 8 hours prior to laying the eggs.  This is a problem for forest birds, since PA forests tend to be poor in calcium to begin with, and is exacerbated by the fact that PA has some of the most acidic rains anywhere in the U.S.  

In her 5-year study two forest tracts were “seeded” with crushed dolomitic limestone and two were left as controls.  The species of interest was the Ovenbird.  She hypothesized that perhaps the Ovenbirds were consuming snails as a calcium source.  During the course of the study, she found that the number of snails in the treated areas increased 10 fold.  She also found that while the territory size remained the same, the number of Ovenbird territories in the treated blocks also increased.

However, there isn’t much documentation on the actual consumption of snails by birds in the U.S.  She also set out several feeder stations baited with snails and mealworms and monitored them with motion-sensing cameras.  Although many species visited the feeders, only the Brown-headed Cowbird was actually caught in the act of eating snail shells.  Cowbirds require large amounts of calcium because of their egg-laying behavior and readily consume snail shells.

Minutes taken by Nan Butkovich, Secretary