Tuesday, May 20, 2008
The Alguita returned yesterday from an overnight trip acting as tow and the escort for the first and only sea trial of the vessel Junk, http://junkraft.blogspot.com/. The raft, constructed out of 15,000 plastic bottles is setting sail for Hawaii on the 1st of next month and I think everyone is happy to say the trip was quite successful.
We maximized our time out on the water and ran two manta trawls last night hoping to capture some myctophids or lantern fish to add to our collection caught in almost all of our night time trawls by the dozens on our trip back from Hawaii.
Myctophids are a large fish family consisting of 246 species in 33 genera and can be found in almost any oceans of the world that provide sufficient depth for them to retreat down to open darkness at 300-1200 meters during the day. But at night they are quite abundant and a significant constituent of the largest daily migration on the planet, of organisms from the depth of the ocean up to the surface to feed.
On the trip back from Hawaii an interesting question was raised when we saw over and over again so many of these fish mixed in with so much plastic debris. The fish that were captured in our manta trawls from the trip home have all been separated out and are currently being analyzed by our resident ichthyologist Christiana, who to date has done a gut content analysis on over 200 of these fish finding plastic fragments in the stomachs of 38% of the fish, with a record maximum size piece of 5mm.
We caught a few fish in the trawls from 2 nights ago but no myctophidae that I could identify in the field. It remains to be seen what we will find once we get the samples back into the lab, but my suspicion is that its simply too shallow a habitat for this species to be in any high abundance.
The picture is of the Junk (proper noun), as it sets sail speeding up to a brisk 3/4ths of a knott; it’s a long ways to Hawaii.