Today we have been doing point counts and line transects around the north side of the Jones Bank and in a line over the bank. When we reached the bank, all life seemed to have been sucked from the sea. It was as if the Dementors had paid a call. Our point counts from here were Dull Dull Dull with no birds over a three hour period, apart from one associated gannet that was stupid enough to be in the count area at the time of a count. Here is the datasheet as proof. In case you were wondering what FFS stands for on the sheet, it was Adam's hand-writing and I didn't understand what it meant.At the start of the day, Adam picked out a very distant group of gannets that were swooping low over the sea as if there were dolphins, but they were just two far away to tell. We called in Clare and she decided to see if she could hear them vocalising. To do this, she used a sonobuoy. These are derived from devices that used to be thrown out of military aircraft to listen out for enemy submarines. It was discovered that you could also hear whales, and with modification of the electronics to listen to a wider range of sound frequencies, it is possible to hear smaller species.
The photos illustrate the sequence for deployment of a Sonobuoy. It is a metallic cylinder that looks like a mini depth-charge and is thrown over the side of the ship. Then there is an anxious wait to see if the a small inflatable bag bobs to the surface (not guaranteed). The bag contains an antenna that connects to the electronics and the hydrophone. The device emits a radio signal to transmit all the noises in the water detected by the hydrophone. It is Clare's job to listen out for any noises that would come from a whale, dolphin or porpoise. In this case, unfortunately, we drew a blank.
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