Thursday, March 23, 2006


Well not really, but this is pretty cool:

"Big Brother" Peers Into Black Drum Bedrooms

A team of scientists from the University of South Florida College of Marine Science (CMS) recently deployed unique instrumentation to locate sound producing black drum fish that raise a loud chorus when they spawn and then determine if the sound production was matched by real results - tight clusters of newly fertilized fish eggs.

"“Sound production by black drum serves as proxy for spawning," said marine biologist Jim Locascio. "We want to see if it is possible to find out how much sound production from the black drum equals how much egg production."”

Locascio teamed with chemist and environmental scientist Eric Steimle (, who developed a radio-controlled guided surface vehicle (GSV). For the deployment, Steimle's GSV carried a DIDSON imagining sonar and a hydrophone listening device to eavesdrop on the spawning sounds of black drum.

To compliment data collected by the DIDSON, USF Center for Ocean Technology engineer Bill Flanery contributed SIPPER, an imaging sensor mounted underneath the GSV. SIPPER was installed to digitally image and count small particles in the water - from seaweed to plankton - as the GSV -criss-crossed the football field-sized canal area. They hoped that SIPPER would discover clusters of newly fertilized fish eggs in the singing locations.

"The DIDSON creates images from sound and provides near video-like quality," explained Locascio. "We used DIDSON as a high resolution fish finder to image the spawning fish and then have SIPPER image and count the eggs being produced."

Their previous research used only hydrophones to locate the sound producing fishes, but this research attempted to image the adults and newly spawned eggs, giving a comprehensive look into the activity and production of the spawning population.

To test the unique system, the team traveled in mid-March to black drum spawning grounds in the canal system of Cape Coral, Florida, near Charlotte Harbor. The canal system is in the back yards of residential areas where Locascio and colleagues in 2005 were called in by residents to help explain odd noises from the canal, sounds so loud and spooky that residents were left unnerved. CMS researchers subsequently identified the sound as black drum males crooning love songs during spawning. The canal system is not far from an area near where CMS researchers recorded fish raising a chorus when Hurricane Charley rolled over the same waters in 2004 (

"All systems operated well and weÂ’re analyzing the data,"” reported Locascio after the test.

Locascio and plankton biologist Andrew Remsen, who are analyzing the images collected by SIPPER, want to determine if the sounds picked up by the hydrophones are concurrent with the number of eggs seen in the SIPPER images. To do so, they are looking at tens of thousands of digital pictures that are cross-referenced to exact locations in the area that SIPPER and DIDSON, riding under the GSV, surveyed together in real-time.

SIPPER can image and identify objects down to 1/4 of a millimeter and image subjects as small as a human hair while viewing 15 liters of water every second.

According to Flanery, an early concern was that riding just beneath the surface SIPPER would be imaging a lot of bubbles and that it might not be able to easily tell the difference between bubbles and fish eggs.

"We were pleasantly surprised to find that the images were easily distinguishable because SIPPER'’s recognition software was able to sort the images,"” said Flanery.

This was the first field assignment for SIPPER and DIDSON to jointly ride as GSV passengers and explore the relationship between male fish spawning sounds and the discovery of newly fertilized eggs. It was also the first deployment of the third version of SIPPER, SIPPER3.

"“Eric'’s vehicle never carried so much weight at one time, but it performed magnificently," said Locascio. "SIPPER also set new achievement levels."

Spawning season in the area is drawing to a close, so the research team is checking their data a fine-tuning the equipment for bigger experiments when the encore begins.

The University of South Florida is on track to become one of the nation's top 50 public research universities. USF received more than $287 million in research contracts and grants last year, and it is ranked by the National Science Foundation as one of the nation'’s fastest growing universities in terms of federal research and development expenditures, and by the Carnegie Foundation as one of the 95 top universities nationwide in research activity. The university has a $1.3 billion annual budget and serves nearly 43,250 students on campuses in Tampa, St. Petersburg, Sarasota/Manatee and Lakeland. In 2005, USF entered the Big East athletic conference.

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