Reef and Fishery Assessment of Navassa Island National Wildlife Refuge

On April 23, 2009 scientists from the NOAA's Southeast Fisheries Science Center in Miami Florida (SEFSC) departed from San Juan, Puerto Rico aboard the NOAA Ship Nancy Foster. Their destination: the Navassa National Wildlife Refuge. Along with the NOAA scientists are researchers from the University of Miami's Rosenstiel School of Marine and Atmospheric Science (UM/RSMAS), the US Fish and Wildlife Service (FWS), and the Director of the Fondation pour la Protection de la Biodiversité Marine (FoProBiM), an NGO based in Haiti.
This work is funded by the NOAA Coral Reef Conservation Program.

Tuesday, May 5, 2009

Elkhorn Coral Mapping

During this visit I attempted to repeat my 2006 circum-island snorkel to map the shallow Elkhorn coral population. I am really disappointed that I was only able to survey the west side of the island due to rough conditions on the north and east sides. Since the coral grows on the wall I have to snorkel very close to the rocks and mark each colony with a waypoint using a hand held GPS in a waterproof case. The photo shows the view from a snorkel perspective.
However, I was able to cover nearly 2 miles of coastline and count approximately 1000 colonies of Elkhorn coral! Each yellow dot on the map is a waypoint marking the location of a single colony. They appeared to be healthy and thriving as I remembered from our last visit 2 1/2 years ago when I counted approximately 900 colonies in this same stretch of coastline. It is very difficult to count colonies so finding 100 more on this visit does not necessarily mean there is more coral. Elkhorn coral colonies can split into smaller sections as it dies back so that one large colony may appear to be 2 or 3 smaller colonies on a subsequent survey which can really confuse things for us coral counting types! Regardless, this survey shows that there has not been a major loss in elkhorn coral aalong the west side of Navassa in the past 2 1/2 years.

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