Archive for November 20th, 2008

November 20, 2008

Heron Nests in November


This morning a gorgeous great blue heron flew just over head with a gigantic branch in its beak.  At first, this sight just didn’t register with any logic I had stored in my naturalist brain.  And then I remembered, in Florida, winter is nesting season for many birds. 

Florida has two major seasons: wet and dry.  Wintertime for the bulk of the United States is dry season in the sunshine state.  Less rain means lower waterlines in many of the river systems, ponds, lakes, and streams in the area.  And lower water means concentrated fish stocks.  So when is the best time to be a fish eating heron or stork in Florida?  Right now. 

Year after year a pair takes up residence in tall pines near us and makes use of the same nest each season.  I’m not sure if its the exact same female and male, or if they add significantly to their home with every nesting season, but it is fantastic to watch the ceremonial exchange and presentation of nesting material between partners.  I can’t wait to start the watch for hatchling herons. 

November 20, 2008

Banking Elkhorn Coral for the Future

(c) USGS: Caroline Rogers

Apparently a researcher with the University of Alberta is building a sperm bank for Elkhorn coral (Acropora palmata).  This past summer Dr. Acker, a frozen tissues expert, joined a group of coral researchers during an elkhorn spawning event and attempted to freeze eggs, sperm, and larvae.  They were successful with the sperm, but it doesn’t appear that they were able to preserve eggs or larvae. 

My only real concern with this sperm bank is that packets were apparently collected from just one area of a reef and from only “thirty to forty Elkhorn individuals”.  As recently discovered, the genetic toolbox for Acropora species might be mightier than we think.  It would be a good idea to bank more populations to ensure that long term genetic viability is likewise preserved.  I’m also curious to know how effective these frozen sperm are when, well, thawed and brought back to life.  In fact, maybe we would better serve our corals to simply learn more about their population genetics for conservation.

Would you be shocked to know that this sperm bank isn’t the only one of its kind for frozen wildlife tissue?  Well, don’t be!  The San Diego Zoo has had the Frozen Zoo project for ages hosted through their center for Conservation and Research on Endangered Species (CRES).