Cosumnes birds the last several days

Glennah Trochet

Dear Birders,

I have been out seeking birds regularly at the Cosumnes River Preserve in southern Sacramento County the last several days.  On Wednesday the 4th, I did some trail recovery in and near the Accidental Forest, cutting a trail through blackberry to the Triangle Pond to the north.  The spur out to that area was still shallowly under water.  Swimming/walking in that road was a mink.  After finishing out there I walked from the equipment pad to the pump on Wood Duck Slough and back.  There was a pair of Oregon juncoes along the west side road.  I've checked the area three times since, and I've not turned them up again.  Migrant numbers and variety were decent:
Hammond's flycatcher-  2
Cassin's vireo-  4
warbling vireo-  9
Swainson's thrush-  17
orange-crowned warbler-  4
Nashville warbler-  1
MacGillivray's warbler-  3
common yellowthroat-  5
yellow warbler-  5
Townsend's warbler-  2
Wilson's warbler-  17
western tanager-  10

On 06 May I visited the TNC Barn ponds, checked the ponds along Desmond Road, and then those on the northern part of Lost Slough (more trail recovery there).  I ended the morning by visiting the heronry at Horseshoe Lake on Valensin Ranch.  There were some things of minor interest:
blue-winged teal-  a pair on the Barn Ponds (BP)
semipalmated plover-  5 (BP)
spotted sandpiper-  1 (BP)
still a fair variety of common shorebird migrants, but numbers much reduced from last weekend
Forster's tern-  2 (These were reported to me by a birding couple on Desmond Road- I did not see them myself)

The Horseshoe Lake Heronry had 22 active great egret nests, but of great blue heron, snowy egret, cattle egret, black-crowned night heron and double-crested cormorant I could find no evidence of nesting this year.  It appears that all of the cormorant nests of previous years are gone, perhaps deconstructed by the birds that are nesting to refurbish their own structures.  There were only a few night-herons flying around, not the 100+ seen on the last couple of visits.  A female hooded merganser had eight 50-60% grown young swimming behind her as they passed three males loafing in the emergent vegetation.  I found a single white-crowned sparrow and Savannah sparrow out there, too.

On Saturday the 7th I did this month's Tall Forest bird survey.  No water was to be had on any of the fields, so waterfowl and shorebirds were very scarce.  More than making up for that were the numbers and variety of regular songbird migrants, especially in and around the Accidental Forest.  It was clear that warbling vireos, Swainson's thrushes and Wilson's warblers were extraordinarily common, so early on I started keeping a rolling tally of these.  I wonder if there wasn't a pulse of migrant Bullock's oriole and black-headed grosbeaks (seems especially late for the former), for these in particular were singing up a storm, in a way that they haven't been recently.  The highlights included the following:
bald eagle-  one large youngster in the nest
western wood-pewee-  7
Pacific-slope flycatcher-  5
western flycatcher-  2
Empidonax sp.-  1
Cassin's vireo-  1
warbling vireo-  40
cedar waxwing-  4
Swainson's thrush-  121
white-crowned sparrow-  2
Savannah sparrow-  3
yellow-breasted chat-  6
Bullock's oriole-  40
orange-crowned warbler-  7
Nashville warbler-  2
MacGillivray's warbler-  1
common yellowthroat-  12
yellow warbler-  5
black-throated gray warbler-  1
Townsend's warbler-  7
Wilson's warbler-  41
western tanager-  16
black-headed grosbeak-  60 (probably low)
blue grosbeak-  1
lazuli bunting-  1

On Sunday I did a transect survey on the floodplain east of the Tall Forest for the wildlife museum at UC Davis.  After that I again walked from the pad to the pump on Wood Duck Slough and back.  There were still lots of warbling vireos, Swainson's thrushes and Wilson's warblers, but there was much less song and fewer chases involving American robins, Bullock's orioles and black-headed grosbeaks..  I concluded the morning with a check of the Desmond Road ponds.  These were this day's notables:
greater white-fronted goose-  23
American white pelican- 25
black-necked stilt-  12
American avocet-  8
killdeer-  5
semipalmated plover-  2
dunlin-  6
least sandpiper-  12
western sandpiper-  210
long-billed dowitcher-  110
Pacific-slope flycatcher-  2
Cassin's vireo-  2
warbling vireo-  20
common raven-  1
Swainson's thrush-  35
Zonotrichia sp.-  2
orange-crowned warbler-  3
Nashville warbler-  1
MacGillivray's warbler-  1
common yellowthroat-  10
yellow warbler-  6
Townsend's warbler-  1
Wilson's warbler-  25
western tanager-  6

The NacGillivray's warbler was singing an uncommonly sweet song.  The cadence and pitch change were pretty typical, but the notes themselves were sweet downslurs.

This morning I did another survey for UCD, this one a point count survey in the Tall Forest, between walking from and back to the equipment pad.  There were fewer warbling vireos and Wilson's warblers, but Swainson's thrushes remained numerous.  Highlights:
bald eagle-  2
acorn woodpecker-  1
Pacific-slope flycatcher-  1
Empidonax sp.-  1
Cassin's vireo-  1
warbling vireo-  8
Swainson's thrush-  68
yellow-breasted chat-  1
orange-crowned warbler-  2
Nashville warbler-  1
common yellowthroat-  3
yellow warbler-  3
Wilson's warbler-  12
western tanager-  8
lazuli bunting-  1

At one point on my dawdle down Wood Duck Slough, I was startled to high alertness.  I was abreast of a dense tangle of prostrate California grape between two and three feet thick.  Something right next to the trail didn't like my proximity and started crashing through the vegetation, which I watched shuddering as this animal made its way some 50-60 feet until it came to a sudden stop.  I watched and listened for a bit, but I came away with no clue as to what that was.

John Trochet