High-Tech Spying on Snapper in Gulf

Sitting on the bottom of the sea 100 feet underwater in the Gulf of Mexico on a cloudy January day, three words come to mind: cold, dark, and lonely.

Think of sticking your face into a bucket of water and ice. Then imagine the water in the bucket is so dark you can scarcely see your hand on the end of your arm. Welcome to Steve Szedlmayer’s laboratory.

Steve Szedlmayer, a professor working out of Auburn University’es Department of Fisheries, readies a receiver to be placed 100 feet beneath the surface of the Gulf of Mexico. The receivers are used to track red snapper fitted with transmitter tags. This device will be installed at a research site 23 miles offshore. (Press-Register/Ben Raines)

The professor, working out of Auburn University’s Department of Fisheries, has been studying red snapper in the Gulf of Mexico since 1990, a 20-year project that has required thousands of scuba dives and allowed Szedlmayer to keep tabs on some individual fish for years. It has also given him unique insight into the ecological impact of the hundreds of artificial reefs off Alabama.

“The basic message is that artificial reefs work. I never believed I’d be saying this 20 years ago. I thought it was a joke. We used to say, ‘Oh my, sinking another ship. Oh what a waste,” Szedlmayer said Thursday. “At this point, I’m convinced that they produce fish, rather than just attract fish.”

That conclusion is inescapable, said Szedlmayer, based on his studies of how long snapper stay on the reefs, what age they arrive at the reefs, what they eat, how quickly they grow and where they concentrate in the Gulf.

The task for Szedlmayer and two volunteer divers — Rusty Hensely and Keith Simmons — last week was to retrieve five expensive underwater receivers and install new ones in their place. The receivers were attached to anchors on the seafloor and suspended with floats so they hung about 15 feet above the bottom. They were designed to record the comings and goings of red snapper fitted with special transmitters on a small artificial reef 23 miles offshore. The

transmitters are surgically implanted in bellies of fish Szedlmayer catches with a rod and reel.

He has been using the array of receivers to track the activities of a group of snapper since August. His data is unique in the scientific world as it provides a 24-hour-a-day log of where individual fish are in relation to their home reef. He can also follow the travels of individual fish from reef to reef by tracking them in real time from the boat with a hydrophone designed to pick up the distinctive pings of the transmitters.

“The precision of the system is incredible. We can track these fish down to their exact position at every moment,” Szedlmayer said. “As far as I know, this system has only been used one other time. I think you will be seeing a lot of other people using it soon.”

Each of the five receivers can record about a million passes by fish. Szedlmayer said it takes about six weeks to fill up the receiver’s memory capacity. That leaves him with roughly 5 million data points to process, a rich trove of scientific information.

But that data comes at a price, namely monthly trips to the seafloor no matter how cold the ocean gets. Most people, scientists included, quit diving in the Gulf in November, when the water temperature drops into the 60s. By January, the temperature hovers around 59 degrees.

The first trick to changing out one of the receivers is finding it. The boat hovers over GPS coordinates associated with a receiver and two divers jump in, swim to the bottom and begin searching. One diver settles to the seafloor and holds the end of a length of rope. Holding onto the other end of the rope, the other diver swims in a circle around the stationary diver and hopes the rope catches on the anchor chain for the receiver. If all goes right, they can usually find the anchored receiver within a few minutes.

But for the diver sitting still and alone on the dark bottom of the Gulf, those can be long and lonesome minutes, with the only sound the gentle burble of exhaled bubbles rising toward the surface.

Szedlmayer has arrays set out on the seafloor in other areas as well, including in shallower water. While he said he can’t draw too many conclusions about the effect of the oil spill on the snapper population at large, he said his research did show that the fish stayed in place on their reefs even as oil drifted over them.

“We’re certainly hoping that we can do an extensive study of whether there was an oil effect or not. One of the aspects we did look at was the age zero fish. We’ve got a long term database on that,” Szedlmayer said, explaining that the young of the year typically settle onto small reefs during the summer.

He said the initial data suggests that there were not a lot of snapper on the reefs that were born this year. Part of the reason, he speculated, was that last year was an extremely productive year for snapper, meaning the reefs were full of 1-year-old snapper.

“The reefs are density dependent. If the house is already full, you can’t let anybody else in, and recruitment was so good last year,” he said. “But, we had cold water upwelling this summer. You had the oil spill. Then you had the extremely high number of age one fish this year.”

In the end, Szedlmayer said, it will take a lot of research to tease apart the effects of those influences. Even then, he predicted, it will be hard to determine what impact the oil spill had.

Click to Watch a Video of Spying on Snapper in Gulf……….

Lake Watch of Lake Martin impacts statewide water policy

Lake Watch of Lake Martin (LWLM) members have been vigilantly watching over the waters of Lake Martin for nearly two decades. Under the leadership of LWLM President, Dick Bronson, the group has monitored lake water quality; conducted lake clean-ups; collaborated with Auburn University, Alabama Power Company, and state agencies in conducting scientific studies(1) of the lake; and educated countless children and adults on watershed stewardship and how each stakeholder can make a difference in keeping the lake clean.

Since LWLM began water testing in mid-1993, AWW-certified LWLM volunteer monitors have submitted nearly 1,600 water quality records (water chemistry and bacteriological records) from 32 monitoring sites to AWW’s statewide water quality database(2).

LWLM monitoring sites on the lake, the Tallapoosa River and tributary streams

Recognizing the high quality of Lake Martin’s waters, and that it is one of the cleanest lakes in the state (3) , Dick began building a case for upgrading the lake’s official Use Classification(4). An upgrade to Outstanding Alabama Water (OAW, achieved for part of Wolf Bay by the Wolf Bay Watershed Watch group(5)), would establish stricter water quality standards for the lake, and ultimately provide stricter limits on the amount of pollutants allowed into the lake.

Armed with nearly two decades of dedicated watershed stewardship and 14 years of AWW-certified citizen water quality data, LWLM submitted a formal request to ADEM for OAW classification for the lake in 2006.  However, the request was not approved because the rules for the OAW classification simply didn’t fit a man-made reservoir like Lake Martin – they were written for natural bays and free-flowing rivers and streams.

Through collaboration with ADEM and the Governor’s Office, the idea of creating a new designation for man-made reservoirs emerged. Dick got the call to attend a public ceremony at Children’s Harbor on the beautiful Kowaliga Arm of the lake on December 28th, 2010. Governor Riley made a special appearance to announce the new water designation for the State of Alabama – Treasured Alabama Lake (TAL).

Governor Riley signs Executive Order 52 establishing the TAL designation for lakes

This designation applies to any reservoir in Alabama that meets the criteria established for TAL, as Martin does. He also announced that Lake Martin would be the first lake in the state to earn TAL status. Details are still being developed for the official TAL designation, but as Governor Riley put it  “what does it (TAL) do ultimately…it says that no matter what happens over the next generation, the water here (in Lake Martin) will never be degraded from what it is today.”

LWLM President Dick Bronson presents Gov. Riley with a LWLM t-shirt

Listen to LWLM President Dick Bronson’s Speach

Watch the Alexander City Outlook video

              Watch the CBS Channel 8 News report             

Read more about the event in the Dadeville Record

Many thanks go to the leadership of Governor Riley, and Mr. Lance Lefleur, Director of ADEM, and particularly to the tireless efforts of LWLM volunteers and their tenacious leader, Dick Bronson – job well done!!

(1)See the following links for more information on LWLM collaboration with scientific studies: Tallapoosa Watershed Project, Alabama Power Lake Study, Sandy Creek Watershed Study).

(2)To access the AWW statewide online database, go to www.alabamawaterwatch.org, and click the AWW Data menu).

(3)According to ADEM water quality trend data, see the 2010 INTEGRATED WATER QUALITY MONITORING AND ASSESSMENT REPORT Water Quality in Alabama).

(4)See the Alabama Clean Water Partnership brochure for information on ADEM Use Classifications).

(5)For more information on OAW classification for Wolf Bay see Outstanding Alabama Water (OAW)).

 

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