12/22/08

#10: Re-sighting of entangled whale Eg #3294

Thursday morning (Dec. 18), Clay George, a wildlife biologist with Georgia Department of Natural Resources (GDNR) Wildlife Resources Division, called to ask if anyone was available for the day to help obtain hydrophone recordings of right whale mom/calf pairs. Fortunately, I had the day off so I immediately jumped at the opportunity to get out on the water. Clay said they planned to launch the boat out of St. Simons Island, GA at 9:15 a.m. (1.5 hours N of Fernandina Beach, FL) and it was 8:00 a.m. when I got off the phone with him. I grabbed my survival suit, packed a quick lunch and rushed out the door. I made it to the St. Simons public boat landing by 9:14!

There were four of us on the boat; Clay and Mark Dodd from GDNR and Stephanie Grassia from the Wildlife Trust-Georgia (WT/GA) aerial survey team. We headed out of St. Simons on GDNR's research vessel Hurricane around 9:30 a.m. and made our way east through the channel. All of the survey planes were in the air that day so we were hoping to get a lot of hydrophone recordings of mom/calf pairs. Little did we know that we weren't going to be doing any recording!

We were about 5 minutes out of the St. Simons channel when we first saw the twin otter, WT/GA's aerial survey plane. They immediately broke from their survey line and began to circle over who we would soon find out to be Eg #3294 (the entangled whale our team saw on Dec. 8). We got the confirmation from the WT/GA team via VHF radio that it was in fact Eg #3294. I immediately became excited by this news because we hadn't seen this whale for over a week but primarily because I knew this was going to be much more exciting than obtaining hydrophone recordings! Clay and Mark went into 'disentanglement mode' and began the extensive protocols involved with an entangled whale.

Although disentangling a whale can be very dangerous, Clay and Mark have had extensive training and are authorized by the National Marine Fisheries Service (NMFS) to work with entangled whales. However, Stephanie and I had not had any previous disentanglement experience so we were assigned less involved jobs taking photographs of the whale and filming the disentanglement effort. After about 1/2 an hour of preparing gear and consulting other disentanglement experts from the Provincetown Center for Coastal Studies (PCCS), Clay and Mark formulated a plan to attach a satellite telemetry buoy to a portion of the 300 feet of trailing line. The telemetry buoy will track the animal via satellite and VHF and will potentially allow for future disentanglement efforts of this whale.

In order to attach a buoy, we first had to grapple the trailing line and bring as much of the line along side the boat so that the buoy can be attached approximately 2 body lengths behind the whale. The WT/GA team was critical to making this a successful disentanglement effort. Communicating via VHF, they alerted us to the position of the whale and the behavior of the trailing line (they circled over the whale for over 4.5 hours!). With Clay at the helm and Mark on the bow of the boat with the grapple, we approached the whale and waited for the WT/GA team to tell us the best time to throw the grapple. Mark's first throw was right on and we began to haul the grapple line toward the boat. My job was to pull the trailing line that was aft of the grapple into the boat and to cut the line after Mark attached the telemetry buoy. The first attachment was a success and we managed to initially remove about 200 feet of trailing line.

As we continued to monitor the buoy we realized it was not breaking the surface of the water (the buoy must break the surface of the water in order to transmit a signal) so we organized another approach to attach the buoy farther forward and to remove additional trailing line. Mark made another successful throw with the grapple and we began to work our way up the line, and closer to the whale! At that point, I could almost see all of the line running to the whale but the line seemed to disappear as it trailed beneath the whale. The down force of the line was incredible and was quite difficult to hold when the whale would dive, but Clay was able to position the boat behind the whale in such a way that reduced the tension and made it easier for Mark and I to handle the lines. We managed to reattach the telemetry buoy, along with an additional buoy to help keep the telemetry buoy above the water line, approximately 1.5 body lengths behind the whale. In total, we removed about 500 feet of trailing line from the whale. We had done as much as we could for the animal so by 4:00 p.m. we headed back to GDNR where the disentanglement photos that Stephanie took could be uploaded and shared with experts to further evaluate the entanglement.

Friday morning, we were informed by the PCCS that the telemetry buoy had radically changed its position (indicating that the buoy had become adrift) around 6:00pm Thursday night. Initially, I was disappointed because I thought that our efforts had been for nothing and we would be unable to relocate the whale, eliminating the possibility of future disentanglement attempts. But after GDNR recovered the adrift buoy at noon on Friday they recovered approximately 250 feet of additional line that was attached to the buoy! Although, it is unclear what gear may remain on the whale, it is encouraging to know that additional line has been removed from the whale. Further assessment of any remaining entangling gear will be dependent on future re-sightings of the animal so wish us luck and we'll keep you updated on Eg #3294!

- Zach

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