This is a summary of Greg McFall’s presentation

Introduction to Gray's Reef National Marine Sanctuary

-A National Treasure off the Georgia Coast-

            NOAA (National Oceanic and Atmospheric Administration) is a federal agency focused on the condition of the oceans and the atmosphere. It is branched off in to several organizations such as OAR (Oceanic and Atmospheric Research), NESDIS (National Environmental Satellite, Data, and Information Service), NWS (National Weather Service), PPI (Program Planning and Integration), NMFS (National Marine Fisheries Service), and NOS (National Ocean Service. The last one NOS is where the National Marine Sanctuary (NMS) falls under. There are several NMS sites on both the Eastern and Western parts of the United States. Some of these sites are the Florida Keys, Gray’s Reef, Olympic Coast, and a humpback whale sanctuary in Hawaii which is the largest marine sanctuary in the world.

One of the fundamental failures of NMS  is getting the word out about Gray’s Reef. The sanctuary is to promote research, protection, awareness, and to facilitate compatible use with restrictions. It is also to maintain, restore, and enhance the protected area.

Gray’s Reef became a sanctuary in 1981 and an international biosphere in 1986. More recently it has become a habitat of particular concern. It is the only natural area protected in South Atlantic. The reef is around 17 nautical miles off of Sapelo Island. The depths are around 60-70 feet deep. The total area is around 59.76 km² of this area only 0.60% is live bottom.

The live bottom habitat is on a rocky substrate with a “carpet” of attached organisms, which serves as a habitat for others. In one sponge, over 250 organisms from over 50 species are living there.

What is unique about Gray’s Reef is that it lies in a transition zone between temperate and more tropical waters. The currents allow organisms that live in warmer and colder areas to mingle. The outer areas are dominated by the Northern flow of the Gulf Stream and the inner areas and dominated by tidal currents, river runoff, and by the curve of the coastline between the capes.

The geology of Gray’s Reef is ledges comprised of aragonite and calcite limestone deposited during the Pliocene Epoch (5.3-1.8 MYA). Any damage done to this rock by anchors, divers, dredging, etc cannot be regenerated. This rock provides the foundation for the reef. The ledges further consolidate into rock during the subsequent glacial periods. The areas that are now Gray’s Reef were dry land 10-15,000 years age. Gray’s Reef has patchy hard bottom features with very low relief that is sparsely populated and high relief that is densely colonized. These areas are subject to periodic burial and exposure by sand during storms. There is constant change to rock features from weathering and bio-erosion.

The invertebrate population is incredibly diverse and abundant. Many of these are surviving at their distributional limits. They are very well established with some sponges that are 30-40 years old. Gray’s Reef is a tough environment to live in. It is very competitive with seasonal fluctuation of water temperature ranging from 56ºF in the winter and 86ºF in the summer.

There are over 300 species of fish. Most are managed under the snapper/grouper complex. Some of these fish are over utilized. They are extracted faster then replaced. There is a decline in 8 out of the 10 major species. Large sedentary species are more susceptible due to complex life history strategies. The current management of these species is based on the best available science.

There is more fishing pressure today then there was in the past. This is in part due to the ability to locate and capture fish has increased with advances in technology. Boats are higher powered and more efficient. Also resource pressure has increased as the coastal population has increased. Consumption of fish has also increased over the years.

One of the more popular species on Gray’s Reef is the Loggerhead Sea Turtle. It nests from May to September/October. These turtles forage and rest in Gray’s Reef throughout the year but especially during breeding season.

Spotted and bottlenose dolphins are also seen at Gray’s Reef. The Northern Right whale’s only known breeding area is South of Gray’s Reef and can be spotted at Gray’s Reef periodically during the winter. There are only 350 northern right whales left in the world. They can get tangled in commercial and fishing gear.

There are several benefits of NOAA’s monitoring that can help divers such as the National Weather Service. It tells the air and water temperature, direction of wind, sea height, gust of the wind, and wave period at Gray’s Reef on their online site. NWS is currently working on a way to join all their data together to form a divabilty condition.