WCA -
(April 8,
2008)
Rainfall:
Residents
of the
WCA-1:
3.76”
WCA-3A: 4.35”
WCA-2A:
6.2”
WCA-3B: 2.43”
WCA-2B:
2.26”
ENP:
2.82”
All areas
exceeded the mean evapotranspiration for the region of 1.48”.
Water Conservation Areas:
While
rainfall is generally welcome in a drought, it has continued to interfere with
the traditional breeding patterns of wading birds in the
Depths
similarly were POOR for wading birds throughout the region, ranging from 0.89’
to 2.56’ in the Conservation Areas. Wading birds in general need water
depths from 0.1’ to 0.79’ to find appropriate prey species. The current
water depths do not support foraging, which is increasing concern for wading
bird breeding success this year. However, as reported last week, it is
still relatively early in the nesting season for ibis and it is hoped that
these poor hydrologic conditions will have a minimum impact on this species.
More information on nesting is in the Wildlife section of this report.
Marsh
stages in WCA-1 have risen again and are above Regulation, WCA-2A marsh remains
at levels above regulation and canals have likewise risen, and WCA-3A stages
have reached the top of zone E1 of the regulation schedule (see Reg_stages.doc), which is
designed for protection of the Cape Sable Seaside Sparrow.
ENP wetland
water levels (see Stages.pdf) showed
mixed trends last week, due in part to the timing and distribution of Sunday’s
rain event. Water levels were down in both northern and southern areas of
Taylor Slough; at
The
salinity pattern in
Strong flow
reversals pushed Bay water northward into the north central Bay areas of
McCormick Creek and
As a whole
the regional salinity concentrations are near seasonal norms except out west in
areas downstream of Shark River Slough (upstream reaches of
Wildlife:
Spoonbill nesting:
Audubon
reported Spoonbill nesting
in
Other wading birds:
The colony
flight on Tuesday, April 1, was notable for the absence of wading birds in the
northern
Most areas
of the WCAs were largely devoid of birds. Northwest WCA-3A supported moderate
numbers of birds, including storks and spoonbills but scientists noted no large
foraging flocks. A few large flocks of ibis were observed in western WCA-1 but
few birds were seen elsewhere in the Refuge (see nest numbers table for more
details).
[Note:
Comments from John Ogden and Peter Frederick following this report indicated
that there have been other years (1970s and 1980s), following reversals and
poor feeding conditions in their usual WCA nesting areas when ibises formed
large breeding colonies from May into the summer. Areas where the nests
have appeared before have been identified, including north of Big Cypress and
along the southwest coast, as well as L-67, Alley North and Tamiami West; the
latter three sites will continue to be surveyed through the usual scheduled
flights.]
Below is a
summary of the nest numbers for each colony. Attached is a survey coordinates spreadsheet,
a nest numbers table for
comparing nest numbers between 2006, 2007 and this year, and a map showing colony locations.
See notes in the nest number table for additional information not provided in
this summary. Please feel free to contact Mark Cook if you have any questions.
Alley
North Colony
Approx. 35 Great Egrets appear
to be nesting at the southern end of island.
Approximately 300 pairs have abandoned this colony since last month’s flight.
20 Great Egret nests
Again,
a reduction on last month’s count
6th
Bridge
45 Great Egret
nests
Crossover
No nests
Some
foraging was observed under the colony
Jetport
No nests
Hidden
No nests
10 roosting Great Egrets
Tamiami
West
No nests
Tamiami
East
No nests
Heron
Alley
No nests
3B Mud
East
No nests
Big Mel’
No nests
Colony
99
175 Great Egret nests
20
White Ibis nests
Colony
73
40 Great Egret nests
Colony
70
No nests
Colony
111
No nests
New
Colony 1
No nests
New
Colony 2
150 Great Egret nests
New
Colony 3
No nests
New
Colony 4
120 Great Egret nests
New
Colony x
?
Canal N
No nests
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