Gary Davidson wrote:
Ring-billed Gulls sometimes develop a pinkish wash on their breast
> and belly. This is caused by foods that they eat. I'm sorry but
> I've forgotten the details on this one, but I think shrimp is one
> of the food items that is rich in the chemical that causes this
> colour change.
The chemical would be a carotenoid, probably Astaxanthin
derived from beta carotene. It's the same chemical which
makes flamingos pink. The shrimp concentrate the carotenoids
from algae; the algae is what gives some salt lakes their pink
colour, and in some places the salt is commercially harvested
to extract the carotenoids for dietary supplements.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Paul Taylor Veni, vidi, tici -
I came, I saw, I ticked.
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