Underwater robots will assess grouper population

While most people know grouper can make a yummy sandwich, relatively few people know they also make noises.

That characteristic has steered some of the first research dollars flowing from BP oil spill settlements to USF College of Marine Science researcher Chad Lembke.

"First of all it's important, everybody cares about grouper, and it does make a very distinctive sound, and they make it a lot," Lembke told FOX 13 News.

He had just outlined his pilot project to fellow marine science researchers.  He demonstrated how underwater robots are useful tools in monitoring grouper populations in the Gulf of Mexico.

The robots are underwater gliders equipped with devices that can isolate the sounds of grouper and record digital images of those sounds.

The gliders have been used in the past to measure physical attributes of Gulf waters, like salinity, temperature and such.

"They sink, tilt themselves, and soar on wings," Lembke told the other scientists.  "So they go up and down and up and down over and over, and every so often they sit on the surface and transmit data and you talk to it and send it new commands."

The gliders are about 6 feet long, weigh about 120 pounds, and can stay at work for about a month.

The audio recorders have been used in the past as listening posts, attached to buoys or placed on the sea bottom.  

Lembke's experiment will compare the data of the fixed listening posts to his robot-gathered data.

It will also be compared to data fellow researcher Dr. Steve Murawski is gathering by applying facial recognition technology to the task of assessing fish populations.

Both approaches are viewed as potential sources of better population estimates, which are used to set fishing quotas.