WCA - Everglades Conditions Update

(May 20, 2008)

 

Rainfall:

Very little rain fell for a fourth consecutive week across the Everglades and ranged from 0.009” to 0.141”. Rainfall increased in a north to south pattern, with negligible rain in the Refuge and greatest precipitation in western ENP (see attached gif),

WCA-1:          0.01”               WCA-3A:       0.02”

WCA-2A:       0.01”               WCA-3B:        0.05”

WCA-2B:        0.03”               ENP:               0.141”

The mean 7 day evapotranspiration for the region was high at 2.17”; see attached srs pdf.

 

 

Water Conservation Areas:

As in past weeks, recession rates were high in almost all the WCAs due to the lack of rain and high evapotranspiration, and water depths are now declining to depths that are fair to good for wading bird foraging over much of the conservation areas. In some regions the recessions were actually a little too high but this is not a concern given water depths are in general at the high end of wader foraging ranges, especially in WCA-3A and 3B (see attached WCA Stages.xls). Stages throughout the WCA’s continue to decline and are above Regulation in WCA-2A, at regulation in WCA-1 and below regulation inWCA-3A (see Reg Schedule.doc).

 

Everglades National Park:

Little rainfall & high ET caused water levels to decline across ENP wetlands last week.  Water levels dropped by 4.4” at Taylor Sl. Bridge and by nearly 3” in the southern part of Taylor Sl. (at Craighead Pond).  At the panhandle station @ EVER6, water levels were down substantially, by just over 2.75”.  Shark River Sl. (station P33, where no rainfall was measured last week) declined only 0.3” (see Stages.pdf). 

 

Salinity rose across much of Florida Bay last week due to strong southerly winds and high rates of evaporation.  Concentrations herein described should be near their seasonal peaks, unless the rains don’t kick in soon.  Salinity rose slightly in the northeast Bay, into the the upper 30s at Trout Ck & Long Sound/Highway Ck., and toward the middle-30s at the mouth of L. Madeira Bay.  In the Taylor ponds, daily mean salinity remained over 30 psu at Pond 5 (USGS station) and Argyle Hendry (ENP station TR) for the entire week.  As of Sunday, 5/18, the 30d moving average concentration at TR (used for tracking the FL Bay MFL criterion) was at 28.2 psu (up from 24.6 psu last week); with concentrations already over 30 psu for 11 days straight, and sustained high temps & ET, it is possible that we will exceed the 30 psu salinity criterion this dry season at TR.  Salinity rose near 40 psu in the northcentral Bay areas of McCormick Ck. & Terrapin Bay.  At the central Bay station in Whipray Basin salinity moved into the lower-40s.  Salinity in the upstream reaches of Shark River (Tarpon Bay platform) measured slightly above the seasonal norm (mid-teens), holding near 20 psu (see Salinity.pdf).

 

Wildlife:

No surveys of the northern WCAs were conducted this week but conditions in the WCAs are generally conducive to good wading bird foraging and nesting. The short-term weather forecast of below average rainfall is favorable to nesting (inclement weather and associated reversals often induce mass abandonment of colonies at the egg and early nestling stages). Of concern to the endangered Cape Sable Seaside Sparrow is the large Mustang Corner fire in NE ENP. I will provide a map of this fire and summarize potential consequences for the sparrow shortly.

 

 

 


 

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