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Thursday, May 28, 2009

Tim Baerwald does it again- Nelson's Sharp-tailed Sparrow!

Tim Baerwald just called from New Buffalo marsh where his continued searching for Nelson's Sharp-tailed Sparrow has produced its second hit. This time it was a single bird in the New Buffalo marsh shortly after noon. Here is a map showing the approximate location of the encounter, based only on Tim's verbal description to me. The location is accessible only by boat (he put in at Red Arrow Hwy), but you could paddle upstream from New Buffalo beach as well.

Tuesday, May 26, 2009

Fish Crow recording analysis

I have spent hours trying to manipulate my (what I thought were decent) recordings of the Fish Crow, with little success. The versions in the blog post below are ambient captures of the recordings played through my computer- long story... 

Anyway, to begin to look at these recordings more technically, I used RavenLite to produce sonograms of the single caw note this bird gave repeatedly, and to compare with know
n Fish Crow recordings and calls of American Crows as well. Here are the two recordings posted yesterday. First, the single caw note by itself (the caw is the blob directly below the re
d box):
All of the tones here are in the 1.2-1.8 kHz range, with an obvious downlur and 2 overtones. The duration is about 0.127 seconds.

Here is the second recording, in which several American Crows are calling before and after the caw is heard (again the FICR caw is directly below the red box):

Here, all of the tones are in the 1.2-1.9 kHz range, downslurred, and with 2-3 overtones as well. Duration of the call is about 0.115 seconds. In the field, the "caw" note sounded the same each time I heard it, and it was the only sound the bird produced. I heard it in a series of at least 5 calls on one occasion and at least 3 calls in another. The only time I heard a double call I was unable to record it unfortunately.

For comparison, here is a recording from the MaCaulay Library, recorded 25 May 1980 by Thomas H. Davis in New York state (ML AUDIO 26

I selected this recording because it was a single note (not the caw-aw sound) given repeatedly that sounded similar to what I heard, and not some kind of aberrant or context-specific call given singly. Here the sound occurs in the 1.2-1.8 kHz range, also downslurred and with 2-3 overtones and duration about 0.20 seconds. The harmonic above this call is not visible in my recordings, and is likely due to a much better sound quality of the latter recording. 

Finally, here is an American Crow (ML AUDIO 105346) recorded 7 May 1994 in Maryland b
y Geoffrey A. Keller:

Note the very different shape, duration, and especially the modulation of each tonal stripe which is absent in the Fish Crow calls. The range of frequencies here is 1.0-2.3 kHz (or possibly higher depending on which tones you "count"), with duration 0.47 seconds.

Finally, here is a comparison of the first American Crow (left), the Berrien Co. bird (middle), and the New York Fish Crow (right). I'll let you make your own conclusions:

Monday, May 25, 2009

Fish Crow!

After reluctantly waiting over 1 week (sans positive chase reports, no less) to chase the putative 1st state record Fish Crow found by Tim Baerwald and Matt Hysell last weekend, I finally made it to the Forest Lawn Landfill in Berrien County this morning for a try. By the end of the day I had encountered the bird 5 times and recorded its call note twice, and am convinced that it what it is. The bird appeared to be running a clockwise circuit from the top of the center of the dump to a crow roost (which was also attended by multitudes of American Crows) somewhere south and east of the dump, then back, at least 7-8 times during my visit, which spanned 6:30AM to 4:10PM. Here is a map to show the locations I am referring to:
My encounters with the bird occurred at the yellow arrows, 3 from "Vantage 1" and 2 from "Vantage 2". My recommendation to anyone chasing would be to start at Vantage 2 to see if crows are traipsing back and forth between the dump and the south roost. If they are not, only then would I try vantage 1.

Except for a single call, the bird was heard giving only single "caws" which were immediately identifiable in each encounter. This call was very different from that of American Crows, being lower pitched and more nasal. Here are my best two recordings of it ("caw" occurs at ~2.5 seconds into the first video, and ~9.8 seconds in the second video):


Finally, it was often difficult to be sure which bird in the line of sight was responsible for the Fish Crow-like calls. If I thought I had a bird possibly making the calls I tried to get photos of it. The first example is this bird. p7 on the right wing appears to be growing (perhaps this proves that this is NOT the Fish Crow?- any comments on this?):
Here is the same bird in flightIn short, it appears that this 1st state record bird may stick around for a while, and will likely be chasable.
Be prepared to spend some time waiting if the dump is noisy or it is windy, as hearing the birds is tough. The Fish Crow and others were often frustratingly silent as they flew over as well, further confounding things. With patience, however, it seems likely that effort will be paid back with a sighting or two. Good luck!

Monday, May 4, 2009

Woodtick Peninsula weekend 5/1/09-5/3/09

Ever since first laying eyes on the map of the Woodtick Peninsula I have become intrigued by the possibility that the site could represent a top notch landbird migrant trap. My first exploratory trip to the area was on 31 May 2008, and although there were plenty of migrants present we did not hit it during a big push of birds. So I decided to put together a full weekend camping trip to the area to explore the habitats of the area and try to see some migrants. Curtis Dykstra and I made this happen from 1 May-3 May 2009. We kayaked out from the west side of North Maumee Bay and camped near the tip for 2 nights.

The Woodtick Peninsula is located at the SE corner of the lower peninsula (Monroe Co.) and juts SSE about 3-4 miles into Lake Erie. It borders the Lake Erie Gun Club to the north and North Maumee Bay to the south and west. Within the bay are a number of uninhabited small islands covered with forest and other habitats. The white circles represent areas we birded.
Habitat-wise the whole area feels much like Magee Marsh (Ohio), with a canopy of deciduous trees (lots of cottonwood) and plenty of understory and even some wetlands. Grapevine tangles are pervasive. However, there are no trails except game trails, of course.
Much of the area is strewn with litter, surely from stuff that made it into Lake Erie and got pushed in by wind and wave.This tombstone was unexpected.
We essentially had the place to ourselves except during Saturday afternoon when the boaters came out in force. The tip of the Woodtick and the first unnamed island to its west (where we camped) are apparently very popular drinking (and fireworking) locations for boaters.

Now for the birding: Birding was disappointingly modest for each of the three days we were there, with most of the early migrants in but very little of the mid-May contingent present. We did have a few species of note, including 2 American White Pelicans (several were present in May 2008 as well), 23 Cattle Egrets (flying north over the Erie Gun Club on May 1), 2 Trumpeter Swans, at least 8 Black-crowned Night-Herons at the tip, 60 Dunlin at Erie Gun Club, 1 White-eyed Vireo, 1 Gray-cheeked Thrush,  2 Sandhill Cranes (not an easy Monroe Co. bird!), & 1 Great Black-backed Gull. Here are the 23 Cattle Egrets in a very distant digibinned shot (look carefully!):
And here are the pelicans:
We had only nine species of warblers, basically the same mix as being reported at Magee, with Prothonotary and Parula (both singles) being the most notable. Yellow-rumpeds and Palms were everywhere. Here is the female Prothonotary:
There did appear to be a significant movement of northbound raptors present each day, including Harrier, Broad-winged, Red-tailed, Cooper's, and Sharp-shinned Hawks, and Osprey and Peregrine Falcon. Presumably this means that these birds are avoiding Lake Erie to its west, much like birds migrating past Lake Erie Metropark are doing in the fall. Best viewing appeared to be from the tip of the Lost peninsula.

Perhaps as interesting as what birds were present was what birds were not present. Tufted Titmice are simply not there! Brown-headed Cowbirds were nearly absent, and Chickadees were quite rare. Disturbingly, not a single rail or bittern was observed during the entire stay (we even tried tapes at night), surely related to the Phragmites monoculture which dominates every marsh present. Very little cattail was observed.

On the float back to the marina on May 3 we kayaked to the Lost Peninsula, another little-birded gem. The habitat at the tip of the peninsula is very nice for migrant landbirds, though likely privately-owned. Fortunately for us, however, it is easily birded by boat. But my main reason for wanting to check out this location was that in my quest to locate good searching areas for Nelson's Sharp-tailed Sparrows I had overlooked one very interesting spot. On the southeast corner of the marina is a 300 yd spoil which juts into Lake Erie (the white circle in the middle of the photo):
 It is covered in grassy vegetation and has some areas of standing water as well. These are important habitat requirements for this species in the fall. But most important is the overall geography of the site. First, it is located no more than 50 miles SW of Point Pelee and 67 miles NW of Lorain OH, both sites which get this bird annually, so it is likely as close as one can get to the core migration corridor for alterus (Hudson Bay breeders) in Michigan. Secondly, grassy-covered peninsulas jutting out into Great Lakes are the #1 setting for finding this species in most surrouding states, as elucidated in this post. So, anyone with the ability to visit this site during Sep 20-Oct 20 (esp. after big sparrow pushes) is highly encouraged to beat the bushes here. I know I will be trying! Here is a photo of the habitat:
I would of course also encourage anyone who can gain access to a boat to visit the Woodtick area as migration picks up, and in the fall as well. I really do think that this place is likely Michgan's version of a Magee Marsh or Point Pelee, and it is a shame the place is so inaccessible. Imagine what rarities we have missed by having no one out there. What I wouldn't give to be there the night after a huge flight...