One of the terms we frequently use when describing right whale behavior is surface active group (SAG). A SAG has a fairly broad definition--two or more whales within a body length interacting at the surface--but typically, the SAG is comprised of one female and a number of males competing with each other in order to mate with her. Some SAGs are extremely active, with a lot of rolling and white water, whereas others are more sedate. The number of animals in a SAG can range from two or three to more than 40!

For years researchers presumed that the primary reason for a SAG was mating. However, conception is thought to take place in the winter (since gestation is about 12 months and right whales usually give birth between December and February), yet SAGs occur year round. Recent analyses of the composition and seasonality of these SAGs indicate that actually only about half of them include females able to reproduce. Thus, SAGs are not just for mating purposes.

Some have been documented to be all male, or all female, or all youngsters. Our colleague, Dr. Susan Parks from Woods Hole Oceanographic Institution, wrote a paper about SAG behavior in collaboration with Aquarium researchers (see below). She hypothesizes that, in addition to conception, SAGs may serve a variety of different roles including practice, play and social bonding.

Studying the behavior of marine mammals such as right whales is much more difficult than that of terrestrial species, because we get just a glimpse of these animals when they're at the water's surface. But the long-term photo-identification aspect of the Aquarium's program has enabled researchers to answer some very basic and important questions. To see video of a SAG see entry #11 Behavior Video (SAG).

Top photo: Taken by Monica Zani in the Southeast U.S.
Bottom photo: A typically boisterous SAG in the Bay of Fundy. Photo taken by Moira Brown

Parks, S. E. et al. 2007. Occurrence, Composition, And Potential Functions Of North Atlantic Right Whale (Eubalaena glacialis) Surface Active Groups. Marine Mammal Science 23(4): 868-887.

Marilyn

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Labels: Behaviors, Marilyn, Right Whales, SAG

What a Typical Day is Like

Yesterday was our first day on the water, and it was great! Because it takes us about 2 hours to get from Lubec to our survey area in the Bay of Fundy, we left the dock aboard our research vessel Nereid at 6:15 a.m. The crew consisted of Amy, Philip, Marilyn, Cyndi, Yan, Jonathan and two guests: Bill and Claudia. The weather was fine--winds were light and sky partly cloudy. By 9:15 we had found our first whales and the hours flew by as we worked one after another. By "worked" I mean we gathered all the information possible for each whale--the time of its sighting and its location (latitude and longitude), photographs of the head (for the callosity pattern) and the body and flukes (for any scars or marks), behaviors, and associations (whether it was alone or with other whales).

It was good to be back on the water, and we all fell into the various jobs without too much trouble. We took turns photographing, driving and recording the data. One person is the designated "whalewatcher" and that person has to let the rest of us know which whale we're photographing, whether it's a new whale for the day or not, and what information we need from it. It's actually just about the toughest job on the boat--a lot of pressure and no breaks! Yesterday, Philip was whalewatcher, and, as always, he knew many of the whales on sight.

In the eight hours we were on the Bay, we photographed 36 individuals, including four mothers with calves! We also saw three calves without their mothers, but that's not unusual for this time of year in the Bay of Fundy. Calves are getting older and a bit more independent, so although they're still nursing, they may go off exploring on their own for hours at a time while mom is feeding. They reunite when one calls for the other.

The highlights of the day were the curious approaches from three different calves. Just like other baby mammals, right whale calves are curious about their surroundings, and it's not unusual to see a calf lifting seaweed onto its head or playing with a log. Sometimes it's the boat that interests calves and they have been known to spend many minutes swimming underneath and all around our boat, looking at it (and us?) from all angles.


After many hours on the water we finally began heading in at 5:00 returning to the dock at 7p.m., nearly 13 hours after we left! But our day wasn't finished yet. After a quick dinner (thanks, Monica!), we still had to process the data (all the information we entered into the computer for each sighting), upload images from the digital cameras (more than 700!), wipe down the equipment (salt air is tough on electronics), and prepare for the next trip out. Exhausted, none of us had any trouble getting to sleep.

Marilyn

First image caption: Hard at work: Marilyn recording data, Jon checking his photos, Philip ready for the next whale. Photo taken by Claudia

Second image caption: One of the curious calves.

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Labels: Bay of Fundy, Marilyn, Right Whales