12/16/12

Wind, waves, whales—We kept calm and carried on!

There are strange things done in the Gulf of Maine by the light of the December sun
The chasing of whales by damsels three certainly has to be such a one. 
...and so our tail begins. (apologies to Robert Service)

Did we see right whales?... Or should the question have been did we hear right whales?

Our boat based surveys in the winters of  2010 and 2011 to the Jordan Basin area were greatly assisted by sightings of right whales contributed by the Northeast Science Center (NEFSC) right whale aerial survey team. The survey area is huge, and prior knowledge of where right whales had been seen helped us focus our boat surveys to the area with the highest likelihood of seeing right whales in the winter, and hopefully gather evidence to support the hypothesis that this area in the Gulf of Maine is a mating ground for these whales.

Prior to our departure in late November 2012, the NEFSC aerial team had flown the area twice, but not seen any right whales. However, our host for the 2012 survey provided another option. Mark Baumgartner of WHOI (Chief Scientist on this expedition) and his colleague Dave Frantantoni of WHOI used technology to give us the edge we needed to locate right whales acoustically no matter what the sea conditions were—Gliders 08 and 10.


The two autonomous underwater vehicles, equipped with hydrophones and the technology to transmit acoustic data via satellite were our ears to locate right whales. The gliders can be programmed to travel around a certain area, record acoustic data while underwater, and transmit that data back home before continuing on to record more data. This new technology can even be programmed to identify what species of whale it's recorded! The acoustic gliders were deployed on November 12, and before we left the dock we knew they were hearing calls from right whales as well as humbacks, fin and sei whales, and we knew that they were hearing these calls in the area south of Jordan Basin, called Outer Fall.

Click on this link, select glider 10 and you can see why were were full of optimism for right whale sightings.



Our daylight home for the week was the flybridge, located just above the ship's bridge with an eye height above water of 32 to 33 feet, giving us a distance to the horizon of over 6 nm (nautical miles).


Our team of three observers was aided by the oceanographic sampling team and we were able to maintain a watch during the daylight hours (~9 hours) and during all sea conditions which ranged from Beaufort sea state 2-8, and most of that was Beaufort 5-6; wind speed of 10 - 35+ knots, and wave heights of 2 - 12 feet!


Our quarters were very comfortable!
Tracy and Marianna testing out the survival gear!

Our first day at sea was spent with safety briefings and a review of the equipment to be used for oceanographic sampling:


"The Package," as it was fondly called, was a metal cage fitted out with a conductivity, temperature and density profiler, a video plankton recorder and an optical plankton recorder. Mark Baumgartner's team of Nadine Lysiak, Morgan Rubanow, Chris Tremblay and Desray Reeb deployed this instrumentation as well as the echo sounder at 35 different locations during our survey.



Mark Baumgartner showing us how the MOCNESS works: this frame with six nets can be programmed to open and close at different depths to generate a profile of the plankton resource at different depths and was deployed several times in the vicinity of right whales.

Deploying the echo sounder

Deploying the package in sea state 7!


This graph shows the wave heights experienced during the cruise.



The gliders were successfully recovered first thing the last full day on Outer Fall, our best weather day of the cruise.




So - did we see any right whales? Stay tuned yet again as Marianna will reveal our sightings on our next blog...

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