Page 23: of Marine Technology Magazine (April 2019)

and when you add a higher tempera- stars keep urchins under control,” ture to that, it kills faster, causing a said Joseph Gaydos, senior author on bigger impact.” the paper and director of UC Davis’

Fisheries depend on nearshore kelp SeaDoc Society program. “Without forests to form a healthy environment sun? ower stars, urchin populations for ? sh and the broader oceanic eco- expand and threaten kelp forests and

UNDERWATER UNDERWATER system. With the demise of sun? ower biodiversity. This cascading effect has

ACOUSTIC RECORDERSACOUSTIC RECORDERS sea stars, sea urchin populations in a really big impact.” some areas have exploded, substan- For this research, “Disease Epidemic tially reducing the kelp, Harvell said. and a Marine Heat Wave Are Associ-

The sun? ower sea star is large, about ated with the Continental-Scale Col- the size of a manhole cover, and pos- lapse of a Pivotal Predator (Pycnopo- sesses an enormous appetite. It crawls dia Helianthoides),” the other partner over the sea? oor like a robotic vacuum institutions were Simon Fraser Uni- cleaner, munching on everything in its versity, Stanford University, Hakai path. Institute and the National Oceanic and “In California, Washington and parts Atmospheric Administration (NOAA).

UNDERWATER DRONES of British Columbia, sun? ower sea Between 2006 and 2017, scientists and trained citizen scientists with Reef

Environmental Education Foundation (REEF) conducted 10,956 roving-div- er surveys from Southern California to

Alaska. Before 2013, divers reported an abundance of sea stars, but between 2013 to 2017 the population collapsed.

Scientists from Simon Fraser Univer- sity and the Hakai Institute con? rmed the loss from remote Calvert Island in

HANDHELD SONAR

British Columbia. The ocean warm-

FOR DIVERS ing recorded at REEF locations corre- sponds to an increase in water temper- ature by up to 4 degrees Celsius that started in 2014.

NOAA scientists surveyed sun? ower sea stars in thousands of deep trawls from Mexico to the Canadian border and recorded 100 percent decline in all states in deep water down to 1,000 meters.

The research was supported by the

FIND YOUR APPLICATION

National Science Foundation, Natural

Sciences and Engineering Research

Council of Canada, NOAA and the

Department of Commerce.

Marine MammalsOffshore Renewable

In mid-April, the University of Cali-

Energies fornia Press will release Harvell’s new book, “Ocean Outbreak: Confronting the Rising Tide of Marine Disease,” on the oceanic epidemics that are im-

Oil & Gas Defence pacting our food chain and proposing solutions to slow a looming global en- vironmental disaster.

+33 (0)297 898 580 http://rtsys.eu/en www.marinetechnologynews.com [email protected]

MTR #3 (18-33).indd 23 4/11/2019 11:14:40 AM