Wednesday, June 10, 2009

Spring surveys: Week 9, final edition

The transition from migration season to breeding season is essentially complete. For the week ending today, 55 species were recorded on campus on 4 survey days. Nearly all were resident or locally breeding species.

True passage migrants were:
  • Swainson's Thrush (8 June, a new late date for spring in Dearborn by one day)
  • Magnolia Warbler (4 June)
And local breeders (although not on-site) were:
  • Broad-winged Hawk (6 June)
  • American Redstart (4 June)
  • Common Yellowthroat (5 June)
With thick foliage concealing often-silent females, finding late migrants is often a matter of luck. Birding at this buggy time is enough of a challenge that many people quit going out late in May. I have June records for most northern migrants, and I'm sure they are probably more common than even these records indicate. I'll still go out and see what I can find a few times in the next week or so, but the formal spring survey period is over. In my next post, I'll be summarizing the whole season.

Thursday, June 4, 2009

Spring surveys: Week 8

We're in the final stretch of spring migration. In fact, the week ending 3 June will be the last 7-day survey week of the season. The next 7-day period will be surveyed 4 or 5 days, but since things are winding down, I feel I need to sleep past 5 AM for the first time in a month!

This week, 74 species were recorded on campus. There are still northern/boreal-nesting birds trickling through. They included
  • Olive-sided Flycatcher (2 June)
  • Yellow-bellied Flycatcher (1 and 3 June)
  • Swainson's Thrush (28 and 31 May on campus, but through the period at my house in east Dearborn)
  • Magnolia Warbler (30 May)
  • Canada Warbler (29 and 31 May).
Other species of interest that nest regionally, but not on-site, included
  • Acadian Flycatcher (30 and 31 May)
  • Veery (31 May)
  • Chestnut-sided Warbler (28 May)
  • American Redstart (30 and 31 May and 3 Jun)
  • Ovenbird (28 and 29 May)
  • Mourning Warbler (3 on 31 May, 2 on 1 June)
  • Common Yellowthroat (31 May, 2 on 3 June)
  • Hooded Warbler (28 May).
Of interest to me was the reappearance of Brown Creepers. I'd been seeing them regularly through the early part of migration at the north end of campus near the Rouge River. One in particular was singing up a storm. The last time I heard or saw one was 3 May. Then one showed up near the usual place on 28 May, and two were together there on 3 June. We've had nesting records before, so I am keeping my eyes peeled for a whole family.

Wednesday, May 27, 2009

Spring surveys: Week 7

This past week saw a reduction in the numbers and diversity of birds, with 80 species recorded on campus. Daily species totals ranged from 38 to 58, with an average of 51. Nearly every day had wind directions from the north or east, which are not conducive to good migratory flights. As might be expected this time of year, the trees are fully leafed out, more female migrants are present, and the combination of hard-to-see and not-singing made for a challenge.

Of the 18 warbler species recorded in the past week, the highlight was a female Connecticut Warbler on 26 May. Unfortunately, it was seen briefly and not relocated. The dominant
warblers are the mid- and late season varieties: American Redstart, Wilson's Warbler, Canada Warbler, Magnolia Warbler, and Blackpoll Warbler, although numbers are small.

The other "good bird" was the third spring 2009 record for Summer Tanager, this one a female on 23 May. It was also seen briefly before disappearing.

Kingbirds have finally been on the increase, but small Empidonax flycatchers are still scarce. Both species of cuckoos have been seen this week, with the first Yellow-billed Cuckoos arriving on 22 May. On 25 May, three were seen together -- and one was carrying a stick, perhaps preparing to build a nest.

There are still a handful of Swainson's Thrushes being found every day. Other lingering migrants include Black-throated Green Warbler (one heard today) and White-crowned Sparrow (an individual recorded nearly daily up through yesterday).

Wednesday, May 20, 2009

Spring surveys: Week 6

Seven days of surveys yielded 95 species on campus for the week ending 20 May. We tallied over 80 species on both 16 May (82) and 18 May (86, our season high so far). On 18 May, there were 23 species of warblers recorded, with the only regular expected species missing being Cape May.

New spring arrivals this week included Lincoln's Sparrow on 15 May; Black-billed Cuckoo, Blackpoll Warbler, and Mourning Warbler on 16 May; and Yellow-bellied Flycatcher and Olive-sided Flycatcher on 17 May. Also notable were American Woodcock and Golden-winged Warbler on 18 May.

The last couple of days clear nights with south winds swept most of the migrants away, and we await another wave. Flycatchers remain quite scarce. We've had very few Eastern Kingbirds, one Yellow-bellied Flycatcher, and only a couple of sightings of Alder/Willow Flycatchers. Least Flycatchers have been consistent, but we've not recorded more than three on any day. Also conspicuous in their rarity have been Yellow Warblers, which are typically very common. Five has been our top count. Black-throated Blue Warblers are usually less abundant, but have also been rare this spring so far.

Elsewhere in Dearborn...

The big stony vacant lot at the corner of the Southfield service drive and Rotunda has been Dearborn's shorebird "hot spot." On 14 May, a Dunlin and a Semipalmated Sandpiper showed up there. These were both 3rd city records. All week there were plovers (up to 10) as well as one to five Least Sandpipers. Another Dunlin showed up on 20 May for the fourth city record. Horned Larks have been regular, American Pipits have been seen several times, and on 15 May a Northern Mockingbird was seen running around catching bugs!

Among the lumps and rocks, small shorebirds can be tough to see. Several of us have been checking the lot daily. Sometimes visits 20 minutes apart can yield completely different results!

"Psst. I think someone is watching us." Two Semipalmated Plovers.

Dunlin


Other faunal news...
Truly odd was this Beaver photographed by Mike O'Leary at the Greenfield Village oxbow pond. We'll see how much tree trimming the Village allows!

Thursday, May 14, 2009

Spring surveys: Week 5

Surveys were completed every day for the week ending 13 May. The week began rather dismally, but a total of 97 species were tallied on campus by week's end. There were some highlights:
  • An Osprey snagging a fish from Fairlane Lake on 8 May.
  • A Peregrine falcon flyover on 12 May.
  • A Red-headed Woodpecker counted on the North American Migration Count on 9 May.
  • Hooded Warbler, also found on that count.
  • The second Summer Tanager of the season on 10 May.
Twenty-one warbler species were found during the week, although only Yellow-rumped Warblers and Nashville Warblers were counted in two-digit numbers. The day with the highest warbler diversity was on 12 May, with 16 species.

Mid-migration has been stalled. There were few new arrivals this week: Blackburnian Warbler on 8 May, Eastern Wood-Pewee on 9 May, Bay-breasted Warbler on 10 May, and Orange-crowed Warbler on 11 May.

Weather fronts favorable for migrant movement were just not happening this past week, but things look set to change for the next few days. We should see the rest of the expected migrants, as well as larger numbers.