Right Whale Migration Update: April 28, 1999 Today's Report Includes:
Greetings from the Stellwagen Bank National Marine Sanctuary. Sad News For Us All
I went out to Wellfleet to watch the first day of the necropsy. Even in death, right whales are awesome to behold -- they are immense creatures. And they are awful smelly if you're standing downwind from a dead specimen. I saw the cyamid crustaceans (whale lice) that fill the callosities and give them their white color. But when the whale dies, the whale lice start to move out of the callosity, perhaps sensing that their days are numbered and that they'd better find a new home (no such luck in this case). The researchers cut away the blubber using techniques employed by the old-time whalers, pulling away long strips at a time. Every once in a while everyone would back away when a hissing sound was heard. (As a whale decays, gases build up in its body. There is the possibility that the carcass can explode from the pressure of all this "natural" gas.) As they cut away the lower jaw, they must have hit an artery as a torrent of blood gushed out of the body and ran down onto the sandy beach. Baleen and bones were collected and saved for research and display, while the blubber and muscle were discarded. I had never seen fresh baleen up close like this -- everything I have encountered so far has either been around for a while (dried up and brittle samples from other dead specimens) or seen from a distance in the mouths of living whales. This baleen was extremely flexible, with an inner fringe as soft and fine as the hair on your head. The wind ruffled this light-brown thatch which gleamed in the bright sunlight. Although she showed no outward indications of cause of death, the necropsy revealed a broken jaw (right mandible) and breaks on five of the vertebrae (actually, the wing-like structures, three of which are found on each vertebrae). For this whale, the broken pieces were found on the right side, mid-body. There was evidence of internal hemorrhaging (bleeding) before the whale died. Based on this evidence, the research team (consisting of scientists from many institutions including the Mystic Aquarium, the New England Aquarium, the Center for Coastal Studies and others) believe the whale was hit by a ship. Lisa Conger, a researcher with the New England Aquarium, noted that very often animals will not show outward evidence of blunt hits -- such as cuts or scrapes -- unlike encounters with propellers which can deeply cut into a whale's body. The research team took many samples of skin, blubber, muscle and organs to better understand how and why the animal died. There was also some evidence (lesions on the tongue and tail) that the animal may have been sick. The researchers do not think that the injuries killed the whale immediately, but that the combination of injuries and disease may have been too much to overcome. If she was healthy she may have been able to survive the trauma. Staccato (#1014) had been seen as late as April 15th in the northern part of Cape Cod Bay. But on the 20th she was spotted floating off the coast. Within that five day window, she had her fatal encounter. Discovering what vessel hit her will be a difficult task. The major shipping lane to Boston passes through the sanctuary just outside of Cape Cod Bay, and many ships transit the Cape Cod Canal which empties into the bay. (In fact, several whales were seen in the vicinity of the canal just a few days before Staccato was found dead. Researchers do not know if she was one of them.) Right Whales Lose Important Mother As I mentioned before, the loss of Staccato is especially dire because she was a fertile female. Scientists know that she is the mother of at least six calves. Her first calf was seen in 1977 and the last one in 1997. Because Staccato was first seen in 1974 as an adult, her age is estimated at 30 years or more. Losing her means the loss of any future calves--and their descendants too. Because there are only an estimated 300 right whales alive today:
(To respond to this question, please follow the instructions below.) More Cape Cod News As of today, right whales are still being sighted sporadically in Cape Cod Bay and now in the Great South Channel. High winds have prevented some flights and, for those missions that do take off, choppy waters make sightings very difficult. In addition, there has been a report from a private pilot of an entangled right whale in Cape Cod Bay. Helicopter and plane patrols over the past few days have not been able to locate and confirm that entanglement. If such an animal is found, the Center for Coastal Studies' Whale Disentanglement Team is ready to attempt a rescue. A Baby for Baldy? Discussion of CQ #9 Challenge Question #9 asked, why would a right whale appear pregnant in April? (After all, researchers spend winter months off the Georgia coast watching for newborn whales. Shouldn't this whale have already given birth?) The answer is, she probably is pregnant--and we still have a lot to learn about right whale reproduction. For example, we don't really know for sure when conception occurs. Whales display mating behaviors in the Bay of Fundy in late summer, but they also display these social behaviors in Cape Cod Bay in February, as well as other times during the year. It may be that right whales have a longer gestation time than humpbacks and that this particular whale is mid-way through her pregnancy. Or maybe it's a shorter gestation period. Or maybe there is delayed fertilization. Or maybe she's just a fat whale. Who knows? There are still so many things we don't know about whales. Perhaps one of you out there will solve this riddle of the right whales. That's all for now. This is Anne Smrcina, education coordinator of the Stellwagen Bank National Marine Sanctuary, signing off.
How to Respond to Today's Right Whale Challenge Question: 1. Address an E-mail message to: jn-challenge-rwhale@learner.org The Next Right Whale Migration Update will Be Posted on May12, 1999.
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