Total Pageviews

Wednesday, July 27, 2011

Ibis trifecta at Forsythe NWR

White-faced Ibis
     Today I visited Edwin Forsythe NRW in the hopes of finding the White-faced Ibis that has been present for at least two weeks. Dave Eberly and I tried for this bird on July 15th and had no luck although we did have a large flock of about 100 Glossy Ibis. Our timing was bad as we went in the late afternoon and had to battle for a view of the birds as they were all backlit. We were at least rewarded with a nice view of a Hudsonian Godwit.
     Upon arrival at 7:45, I decided to make a quick pass around the refuge to the NW corner of the west pool where the ibis has been reported. The initial pass through the refuge produced many shorebirds and terns but I only located four Glossy Ibis, which quickly dampened my hopes. So on my second pass, I decided to go slowly and watch for other birds in hopes that by the time I arrived back to the NW corner that the ibises would increase in numbers. I drove the road to Gull Pond and climbed the observation tower and who is standing on top but Edie Purnum (BCDC Member) and Mike Rosengarten. They were watching four Black-bellied Whistling Ducks, which would have been a state bird for me had I not just found one in Cape May about three weeks earlier.
Gull-billed Tern at Forsythe NWR
Whimbrel and American Oystercatcher
      Other birds of interest were fifty Whimbrels, a Stilt Sandpiper, one Long-billed Dowitcher, lots of Gull-billed Terns, including youngsters, and many American Oystercatchers. As I rounded the bend and approached the west pool for the second time I noticed a line of cars parked ahead. I got out and set up the scope and was directed to an immature White Ibis feeding among the numerous other shorebirds including Pectoral Sandpipers. That made two ibises for the day. This was my second White Ibis in a little over a week, as I was lucky enough to see the one at John Heinz Refuge. Having now seen two thirds of my hoped for trifecta, I scoped the other end of the pool and noticed that there was a large flock of ibis down at the NW corner of the pond. I quickly hopped in the car and headed down.
     When I set up the scope and scanned the flock the birds took off. So I waited about five minutes and they started to return. Trying to see the diagnostic red eye was quit the challenge however. Finally I saw a bird that was a possible White-faced Ibis but once again the birds scattered but then landed a little farther out. By this time I had reinforcements from other birders. One gentleman finally spotted a bird with a reddish facial area and got most of us on the bird. Sure enough there it was. All three American ibis at one location. And a new state bird to boot.

       Also here are a couple of Dragonfly photos that I need identified. Does anyone know if these are male and female Great Blue Skimmer?

Wednesday, July 20, 2011

#214 and #215

A team from Hawk Mountain visited Delaware County today to tag some vulture chicks. The photo above shows Bracken Brown with a young Black Vulture. The bird was estimated to be about 50 days old. Wing chord measurements taken of the two chicks (currently about 28-30 cm) will allow a more accurate aging. Blood was also drawn to test for lead and heavy metals, although researchers have yet to determine a normal baseline for such contaminants. Both youngsters were covered with curly brown down. Note the visible white shafts on the growing primaries. Fledging occurs 80-94 days after hatching, so these birds are only slightly more than half-way there. They are currently being fed regurgitant, presumably by both parents, one of which was sitting high in a nearby tree during the proceedings.

As Doris mentioned in a previous post, vultures are outfitted with plastic livestock tags instead of leg bands. On Black Vultures these circular tags are bright yellow. The numbers are visible on both the upper and lower side of the wing. So, this fall, if you spot #214 or #215 in the air, please note the date, time, location and behavior and report your sighting. We hope that by tagging local vultures we will be able to get a better handle on the movement of this species, particularly around the Rose Tree Park Hawkwatch area. The researchers, of course, are also interested in larger scale movements and migratory patterns. It is currently thought that family units may be maintained throughout the year. Nest sites are also re-used, so please let us know if you find one. The more birds that can be tagged, the more we stand to learn.


PS Al reports that the two young Turkey Vultures that he found, also in Delaware County, were successfully caught and tagged by the Hawk Mountain team. They are numbers 312 and 313. Turkey Vulture wing-tags are blue. Please also report any sightings of these birds.

Friday, July 8, 2011

The Martins of Glen Mills

On Tuesday, July 5, Doris assembled her volunteers to band what is probably the largest Purple Martin colony in Delaware County. The Glen Mills School has 32 boxes arranged in groups of 16 in a central quad. Three teams (Doris and Don, Lauren and Sheryl, Erika with several helpers during the final hour) worked their way from box to box banding more than 650 nestling purple martins over the course of four hours.

Apartments come in the traditional style or in synthetic gourd form (as seen here), as well as in castle complexes (see photo #4). There are perches and railings good for protecting the home base or enjoying the view. Adults returning with food for the young often sit for some time before entering a nest. We saw them carrying dragonflies and butterflies (definitely one red admiral), but the number of insects they eat must be incredible.

Once each house is lowered, the contents of each numbered compartment are recorded. The young are removed, banded and replaced in the same compartment. Here Doris and Don are working at one apartment complex. . .

. . while Lauren and Sheryl are working on a castle.

At this point in the summer, nests are at various stages. Nests may contain eggs, young hatchlings that are pink and featherless, or larger young, some nearer to fledging. The bellies of the birds this year were prominent, as you can see in the photos of both of these well-fed birds. Most quietly accept their jewelry without protest, but a few do squawk loudly. Interestingly, the stick and mud nests also contain green Ginkgo leaves, possibly as a pest deterrent.

Notice that the tail feathers on this purple martin youngster are still in sheath. The big fat baby bird lips are also apparent. If you look closely, you may even be able to locate the ear.

Many hands are useful in holding the birds since each nest may contain anywhere from 2 to 6 young. Here is a crew of happy helpers (namely, Erin, Ellie, Sarah and Kristen) holding birds. Most nests hold 4 or 5 young, though we did find one gourd with 8 eggs in it. Particularly in colonial nesters, females may lay eggs in other females' nests. If you can slip an egg in for someone else to incubate and feed, that's one extra set of your genes that you pass on. In purple martins, both parents incubate and feed the young.

Thanks to Dale Kendall for providing most of these photos, to Kristen for photo #2 and the video, and to Lauren and Karl for technical help with sizing the photos and video. Click on the play button below to see and hear the birds in action. (I hope it works. This is the first time I have tried incorporating a video clip.)