New England Aquarium
EARLY WARNING SYSTEM
Radio Tracking 1998-1999
(Page sponsored and maintained by WhaleNet)
Tracking: January 25 - 29, 1999
Joe Roman and Amy Knowlton
It isn't often that we get four straight days of good weather off the Florida coast during the winter field season. So nothing was taken for granted during our last week tracking when the longed-for "light and variable" winds moved into the area. From January 25 to 29, we followed #1612 and her calf, through a heavy chop and into calm seas, for more than ninety-five uninterrupted hours.
Right whale #1612 was first identified in 1986 with a calf in the waters off Cape Cod. Most females bearing young in the southeast U.S. migrate to Massachusetts Bay or the Great South Channel in the spring and then move on to the Bay of Fundy in summer. Though this female has followed the migratory pattern from the southeast U.S. to Massachusetts, she has never been seen in the Bay of Fundy. We refer to such whales as offshore mothers, since they appear to go to unknown nurseries outside the near-coastal areas we usually survey.
Her calves have been closely monitored since birth. Born in 1986, #1613 is a male who has been sighted in the southeast, Massachusetts Bay, and the Bay of Fundy; he was last seen in 1996. Born in 1992, #2212 is also a male and has been sighted in Massachusetts Bay and the Bay of Fundy; he was last seen in 1995. We're happy to see that another calf can be added to #1612's brood this year.
Even though we were fogged in for all of January 27, the antenna system hooked up to the wheelhouse on the Jane Yarn allowed us to keep up with the mother-calf pair, noting the mother's swimming pattern and how much time she spent at the surface in different sea states, weather conditions, and times of day. The mother and calf were traveling a lot during this time. The mother's signal would disappear for up to fifteen minutes, and when she resurfaced the signal could barely be heard, making her difficult to track at times. But we'd slowly move our boat in the direction of the signal, sometimes getting just two or three chirps, and then wait for her next surfacing. If her signal was still faint, one of us would seek out her signal with a large directional antenna mounted on the flying bridge atop the bow. We never lost our whales, but the gathering of data in the dark and fog-- especially when the sea kicked up, making sleep impossible and researchers irritable--got old.
After thirty-six hours of no visibility and the same old song-- the piercing "chirp, chirp, chirp", like the drip from a faucet on an upturned pan-- the entire crew was very glad to see the sun rise over an unclouded horizon on January 28. With good visibility and a flat sea, we were able to begin correlating the radio-signal data we had been collecting for the previous two days with the whales' behavior. We noticed that even when we weren't getting a signal from the mother, the calf was often at the surface, lifting its dark head above water or taking a few breaths. It was clear just how vulnerable this calf is, spending so much time with its head above the surface or hoisting its flukes in the air. In centuries past, whalers would rely on calves to help them locate the adult females. An active newborn can be spotted even in a rough sea, giving both mother and calf away. Once approached, both animals would be killed for their baleen and oil.
Though whalers are no longer a threat off Florida, large warships and merchant vessels, some traveling more than 20 knots, pose a risk to the whales. Whenever we see a ship within five miles of our boat, the captain of the Yarn gives a radio call to the approaching vessel, with a report that endangered whales are in the area. The crews of military and commercial vessels have been cooperative and careful to avoid crossing paths with the whales.
On January 29, we completed four days of tracking. The whales had taken us into the warm edges of the Gulf Stream, and their pace had slowed. We were in water over 24 degrees centigrade. As we drifted near the resting pair, translucent Portuguese man-of-wars floated along the bow, a few spotted dolphins crossed our stern, and a large barnacle-encrusted loggerhead turtle surfaced off to starboard. We enjoyed the final hours of this cruise--watching the calf slap its tail in the water and drape itself over the mother's head. It was clear that the forty-five foot mom was this calf's entire world. But for us--after four days at sea and with a large storm drifting east over northern Florida--a long hot shower and a good meal ashore seemed in order. We left the becalmed pair in midafternoon about twenty-five miles east of Saint Augustine, Florida.
With the storm now past, our mission is to relocate the pair with our Cessna tracking plane, so the Jane Yarn can head offshore for another expedition. Whether the whales will turn up farther offshore, down south, or back up north is anybody's guess.
TBA - Data Table of Sightings
Map of 98-99 Right Whale Radio Tracking