GOLDEN ALGAE, FISH DIE-OFF - USA: (TEXAS)
*****************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>
Date: 7 Jan 2011
Source: My Plain View [edited]
<http://www.myplainview.com/news/article_cf64014e-1a99-11e0-a9fc-001cc4c002e0.html?>
Toxic algae bloom blamed for massive fish kill
----------------------------------------------
Officials believe a toxic algal bloom was responsible for the deaths of up to 20 000 grizzard shad last week at Lake Meredith. Charlie Munger, a district supervisor for the Texas Parks and Wildlife Department, said golden algae, a water-dwelling organism that can release a toxin fatal to fish, is the likely reason behind the mass fish kill.
Munger said low water levels at Lake Meredith are likely to have increased salinity and PH levels in the lake, where water levels are dwindling. That chemical imbalance, along with cold temperatures, is likely to have been enough to affect the algae's ability to survive and trigger its defense mechanism -- releasing toxin to kill other organisms to provide nutrients.
The toxin damages the gills of fish but is not believed to be hazardous to humans or other animals, the Lubbock Avalanche-Journal quoted officials as saying.
While the fish kill prompted Lubbock officials to add powdered-activated charcoal to that city's water supply to help prevent a possible fishy odor, something they'll continue for the next 2-3 weeks, Plainview officials did not have to consider treating water here since no Lake Meredith water was being received at the time. Brian Gallaway, the city's well field and lab technician, said this morning that Plainview cut off its Meredith supply 28 Dec 2010, a day or 2 before the fish die-off.
"We usually shut down at the end of the year anyway to do general maintenance," Gallaway said, adding that when they do that the city receives water exclusively from local wells. Gallaway isn't sure when Plainview will begin receiving lake water again. "We're kind of waiting on them," he said, adding, "Sometime this month they're not going to be sending us lake water any more, just well water in Roberts County" as officials work to restore the lake level.
In recent years Lake Meredith, a major source of water for Plainview, Lubbock, Amarillo and other Panhandle-South Plains communities, has seen some of its lowest water levels on record.
According to the Canadian River Municipal Water Authority, on Thursday the lake was at a record-low level of 38.31 feet -- more than 60 feet below its record depth of 101.85 feet set in April 1973.
[byline: Kevin Lewis]
--
communicated by:
ProMED-mail
<promed@promedmail.org>
[Golden algae are estuarine-based (saltwater-tolerant) organisms that are very small (10 um long x 5 um wide). They are generally oval shaped with 2 cup-shaped golden plastids running the length of each side of the cell.
These tiny organisms, when in great number, can cause water to be discolored, ranging from yellow to coppery brown. They may be present in mud and cause problems with inland- or pond-raising of fish. Golden algae do not seem to go away as does red tide.
Large concentrations of golden algae (blooms) can often be toxic to fish.
The toxins affect the gills of the fish, which are the breathing system, thus limiting the fishes' ability to take in oxygen. Death is from asphyxiation, just as it is with red tide. - Mod.TG
A HealthMap/ProMED-mail interactive map of Texas can be seen at <http://healthmap.org/r/00WR>. - Mod.SH]
[see also:
2005
---
Golden algae, fish kill - USA (AZ) 20050529.1492
2001
---
Golden algae toxin, bass - USA (Texas) 20010529.1044]
...................sb/tg/ejp/sh/ll
*##########################################################*
************************************************************
ProMED-mail makes every effort to verify the reports that are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held responsible for errors or omissions or held liable for any damages incurred as a result of use or reliance upon posted or archived material.
0 comments:
Post a Comment