Bob Drewes Reports On Strange Pufferfish Dieoff

L. lagocephalus

Rabbit Pufferfish, Lagocephalus Lagocephalus. Photo by O. Alvheim 2010.

Bob Drewes from the California Academy of Sciences reports on Dr. Tomio Iwamoto‘s findings in the Gulf of Guinea, documenting a strange dieoff of the Rabbit putterfish. A Norwegian research vessel, the Nansen, is conducting a scientific trawling expeditions in the area.

 

According to several staff of the Nansen, such die-offs have been seen before, especially off the coast of Gabon, south to northern Angola, but appear to have become somewhat regular since 2007, usually in March-May.

No explanation has yet been given.

The vessel monitors water salinity, current velocity and temperature at all transects trawled.

None of the Rabbit puffers they studied showed any signs of disease or physical trauma; however, about 4 miles offshore of the town of São Tomé, they came upon a current boundary lined with floating dead puffers.

Jens-Otto Krakstad and Dr. Iwamoto examining dead puffers. Photo by O. Alvheim 2010

Jens-Otto Krakstad and Dr. Iwamoto examining dead puffers. Photo by O. Alvheim 2010

In their report to the STP Fisheries, they consider the possibility that rapid changes in temperature/salinity could account for these die-offs, but so little is known of the oceanography of the two islands that a positive explanation is elusive.

Read more on the Island Biodiversity Race blog.