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taken from Summit News Service ST. ANDREWS -
Marine researchers from the Maritimes and New England are almost as giddy as
new parents after an explosion of right whale births over the
winter. Encouraging Right Whale News! The latest update from Chris Slay, New England Aquarium from Florida, relayed by Laurie Murison, Grand Manan. Northern Right Whale Calving Ground, 03/12/01 I last sent word on the last day of February and
we were in the middle of a frenetic week. From 25 February through 03 March, we
flew all 7 days, although 3 surveys were shortened due to morning fog. In that
one week, we had 50 sightings; 43 were mother/calf pairs. Weather kept us grounded from 04 - 06 March. Upon returning to the daily grind we have seen no more than 2 mother calf pairs during a flight. We were skunked on the 9th, only the fifth time thats happened in almost 70 flights. There may still be 2-3 pairs south of us based on reports from FMRI, MRC and others down the coast but I'd say that most of the class of 2001 is somewhere between Savannah and Cape Cod. Hopefully they'll meet with better luck than #1160, the first confirmed vessel-struck whale of 2001. Number #1160, or Bolo, named for the shape of her callosity pattern which resembles that primitive South American weapon, was sighted by us on 08 December, with another female, #1509 (Rat). These two were hanging out together during mid-December until Rat was seen alone on 27 December. Five days later she was sighted with a calf. It would be another two weeks before we saw Bolo again. When we came across her on 16 January she had also given birth. Her calf has solid white flukes and white-rimmed flippers, which makes the pair instantly recognizable. So when a calf of this description was reported by the University of North Carolina at Wilmington, we were pretty sure we knew the pair in question. UNCW conducted aerial surveys for whales along the coast of the Carolinas during February. They sighted four different mother/calf pairs, including #1970, a mom not seen by the other teams. We appreciate Bill McClellan and his survey team adding this animal to the roster. During the course of their surveys, they located #1160 off of Hilton Head Island, SC and reported that she had been struck by a boat. This was based on the observation of a gruesome series of propeller cuts tracking across her about 10'-12' of her back. That was 16 February. We had last seen this pair off of Amelia Island on 29 January, unscathed. She must have sustained the wounds along the cost of Georgia during the first half of February. Backtracking, Bolo returned to the EWS survey area and was sighted by our crew on 28 February, off Brunswick, GA. The next day, en route to their survey area, the OSS (Offshore) team located Bolo and her calf, near where she was seen on the previous day. Lisa Conger, leader of the OSS team, located the pair by water, enlisting the help of a GA-DNR enforcement vessel. She had a relatively good look at the cuts and reported that the injury doesn't appear life threatening. The lacerations go into the white blubber layer but not too deeply. None of the cuts appear deep enough to effect muscle tissue. From Conger's descriptions and from aerial photographs, it is evident that there is series of cuts along the whale's side, parallel to the ones on her back. This suggests that the vessel that hit her was of the "twin-screw" variety. The length of this series of cutes, their size and the distance between each cut, indicate the boat was probably between 45 and 75 feet, and moving very fast. It would be a reasonable, educated guess that the vessel was a twin-diesel powered motor yacht about 50' long. We've seen a lot of boats like that bombing around the calving ground at speeds well over 20 knots. It looks like #1160 may have tried an evasive dive, as the forward half of her body has no outer signs of injury. The portion of her back that would arch out of the water upon submerging is where she took the hit and she's missing a dinner plate-sized chunk of tissue from the notch of her flukes. Had the calf taken this hit, it would be dead. I think the word Conger used was "lucky". No doubt, there's some guesswork involved in understanding boat/whale encounters. It's hard to know how whales react to oncoming vessels. We have contacted ships from our aircraft on several occasions this season when we perceived there was a potential for collision. While we might observe the vessel making course or speed adjustments, it's difficult to ascertain what the whales hear beneath the surface and how they might attempt to avoid being run over. There are a couple of incidents that give us minimal information about whales' responding to ships. On 10 February, at 1101 hours local, the EWS team noticed a vessel approaching a pair of whales they had finished photographing 2 minutes earlier. The vessel was headed toward the whales so they flew over to get an exact position, vessel name and to radio the ship. The mother and calf were surfacing/submerging, not making much forward progress, very slowly headed south at N30 59.6 x 081 1.9. The freighter Winfield was outbound from Brunswick, N31 01.5 x W081 13.7, heading ESE, 1.9 nautical miles (NM) from the whales. The crew was unable to get a response from the ship on VHF. When the ship was 1 NM from the whales the pair changed direction and began swimming NNE, across the path of the ship. Could this have been a response to detecting vessel noise? The skipper of the dredge Lindholm, knowledgeable about right whale conservation efforts, overheard the EWS crew's attempts to raise the Winfield. He responded and asked the EWS crew for a location and asked which way the Winfield should alter course. He then successfully raised the Winfield, explained the situation and the ship made the suggested course change to port (NE). No change is speed was apparent. When this course change was made, at approx. 1111 hours, the ship was .5 NM from the whales and closing. Until the course change was made, it appeared a collision was imminent. When the ship changed course the whales appeared to respond, possibly to a change in the acoustic signature of the vessel that occurred with the course change? The mother and calf turned and headed WSW. The dredge captain relayed an updated location from the EWS crew and gave the ship an "all clear" when they had passed the whales. At 1117 hours the ship went to a course of ~150 degrees. A rough speed check was done at this time. The ship covered 2.4 NM in 10 minutes: 14.4 knots. Two days earlier, on 08 February, the EWS team began circling a mother and calf right whale for photos and noted a submarine approaching from the southeast. They estimated the sub to be ~3.5 NM away, heading NW, directly to the whale's position (exact times and locations are omitted). The pair was at the surface, swimming slowly to the south. The EWS crew continued circling on the whales while calling the sub via VHF. Contact was made and the sub's crew stated that they would post an additional lookout and reduce speed to 10 knots. The submarine was observed slowing at this time, further reducing speed as it neared the whales. Observers estimated sub's speed. At less than 10 knots. When the submarine was approximately 200 meters from the pair, the whales dove and apparently changed direction, almost 180 degrees. When they resurfaced, less than a minute later, they were approximately 300 meters off the starboard beam of the submarine, heading NE. At this time submarine's crew transmitted that they would maintain a reduced speed. Events such as these will be much less common as the season comes to a close. Halfway through today's survey and only one mother/calf pair has been sighted. It's starting to feel like we're seeing the last of the stragglers at the end of a party. Best Regards, P.S.: The calf count is now 26, minus the one mortality.
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