Has anyone suggested or researched whether hypoxia is contributing to
waterbird declines in Puget Sound? Nutrient runoff from ag & lawn
fertilizers, sewage, etc., causes phytoplankton blooms and oxygen
depletion in bottom waters in many coastal areas, including regions
of Puget Sound (e.g. Hood Canal). The low dissolved oxygen levels
suffocate bottom-dwelling shellfish and force fish to move away from
these areas, thus presumably depleting food supplies for grebes,
scoters, and many other birds. Has anyone researched this in
Washington waters?

Jay Withgott
Portland, OR
withgott at comcast.net



At 8:23 PM -0800 1/17/05, J & B Adamowski LaComa wrote:
>I am by no means a scientist....however after reading recent stories
>and articles sent to me by many of the concerned birders here on
>Tweeters my curiosity got the better of me as to possible reasons
>why these birds have been effected and not others. After reading
>the studies on population declination over a 20 year history I am
>even more concerned. As I see it there are 3 main factors at work
>here:
> (1) Habitat loss
> (2) Introduced predators on juveniles
> (3) Heavy use of Organochlorine Pesticides
>Habitat loss is not news to anybody and predators such as Large
>Mouth Bass can have impacts on any species but throw in wide spread
>usage of Alachlor, Atrazine and continued usage of U.S. banned
>chemicals similar to or identical to D.D.T in other countires and
>there should be no doubt why we are losing some or all of our
>animals. I read a report on line about the effect of interrupting
>the endocrine process in frogs and alligators and was wondering if
>any studies at all had been done to Grebes and similar declining
>population birds and possible biomagnification? Again I am by no
>means a scientist here and am not trying to pin this on the
>Pesticide Industry but was just wondering if anybody had heard, read
>or done any studies in this field?
>
>Bryan LaComa
><mailto:jennandbryan at msn.com>jennandbryan at msn.com
>
>
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