That's a total of about 100 birds found dead, just in the past two weeks.
Experts are analyzing the remains to see if the recent sewage spills in Mill Valley, may be to blame.
During the last week of January, more than 5-million gallons of raw sewage leaked from the Sewerage Agency of Southern Marin into the bay.
"Right now we're not prepared to make any links to that, just to document as much as we can and we send off as many specimens as we can for testing and once those results are in we'll have a much better idea of what's been happening," said Kerry Wilcox from the Richardson Bay Audubon Center.
Now, the Richardson Bay Audubon Center is asking for an investigation. A dozen different bird species have been found since the spill.
