Interns help tag a great white shark

November 26, 2012 by dyertrust

great white shark trackingOne of the most exciting events that an intern here gets to participate in is the tagging of a great white shark. On the morning of 3 November, we were asked to perform this task. Oliver Jewell is the manages our intern group and is also one of the resident biologists studying shark movements and the proposition of home ranges. Our intern team that day was comprised of Matt Smith, Tess Mahoney, Giovanni Vasser, Dawn Watson, and Christopher Algero. Also with us that day was our technology specialist, a highly skilled and fearless man named Ed. We gathered early that day to prepare the vessel, Lwazi, for her brief expedition. Once she was loaded with chum, had her GPS and radio attached, and the tracking hydrophone and computer were on board, Lwazi was driven down to the quay and launched.

After chumming for what did not seem like a very long time our first shark arrived. She was a large shark and would not be our last large shark of the day. Not 20 minutes had passed after her arrival before we were surrounded by sharks of sizes large and small. The duties at this time were important as those on their positions were at their best this day. Tess Mahoney and Dawn Watson were in the crows nest on the lookout for sharks, their words were relayed down to the people on deck so that no one was surprised by a shark. Listening closely to Tess and Dawns warning were Christopher, Matt, and Gio. Chris was on the bait line, it was his job to entertain the sharks and direct them closer to the boat when the time for tagging had come. Ed and Matt were on the chum line, their slosh of fish mush poured expertly from the bucket brought the sharks to the boat. Gio was working the decoy line, his duty was similar to Chris but with a chewy fake seal. Finally last but certainly not least was our skipper and team leader, Oliver Jewell.

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Gigantic calves and thinner mothers!

November 26, 2012 by dyertrust

Gradually as the calves are getting larger (both longer and thicker) their mothers are getting thinner! The mothers do not feed while they are here off the South African coast, but sustain themselves from their thick layer of blubber, which they build up while they are feeding in the Sub-Antarctic waters from January to May.

The southern right whale mother and calf pairs are ruling the bay at the moment! Some days we have had more than 30 pairs. They mainly spend time travelling slowly along kelp, relaxed, rolling, and logging in the same place. The calves are by far the most active and often breach and play around the mother. Maria has been tracking the detailed behaviour of the mother and calves, and they are spending lots of time travelling, milling, or being submerged.

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