Post-Irene. Back on the water…
The field team was able to get back out on the water today after the post-tropical storm formerly known as Hurricane Irene blew threw eastern Canada. Amazingly, the seas laid down from storm conditions surprisingly quickly and we had beautiful at-sea conditions for sighting and tagging whales as well as mapping the patches of prey structured by the Long Eddy. The water was calm with slight swell, the sun was out and brightening the few clouds, and the Long Eddy was clearly visible in the surface water as seabirds, harbor porpoises, and minke and fin whales position to feed.
Out on the water, we quickly identified the individual spotted on other days (fin whale Getz) and began to prepare tagging efforts. The DTAG (the instrument we’re using to study the whale’s movement in relation to its prey and surrounding environment) was positioned into the tagging pole for the first time this field season and we began making close passes at the whale in attempts to land a tag on its back. Unfortunately we never could predict the whale’s next surfacing in order to position the boat close enough to deploy our tag. Given some boat troubles due to a broken bilge pump, we decided to head into harbor after the Long Eddy subsided at high tide and complete these necessary boat repairs.
The team mapping prey in our partner vessel, the Phocoena, saw similar ups and downs throughout the day. The first full echosounder transect recording prey density across the Long Eddy and surrounding waters was successfully completed. Some of the chatter on the boats was that the shear line where prey density drastically drops off was clearly visible in the preprocessed data! However, the team spent the second half of the day troubleshooting a few different issues, including reorienting the towfish’s swim trajectory and retooling one of the echosounders to remove distracting and undesirable noise in the data.
All in all, a strong day of trials that tested both teams. In the end, we’ve come out top and retooled ourselves to be even better tomorrow.
[photo size=’large’ title=’Prey mapping below the Bishop link=’http://superpod.ml.duke.edu/johnston/files/2011/08/TheBishop.jpg’ icon=’zoom’ lightbox=’image’]http://superpod.ml.duke.edu/johnston/files/2011/08/TheBishop.jpg[/photo]