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| November 18, 2010 |
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 On Saturday we worked up our middle track line, surveying straight up the center of Jeffrey's Ledge. Though this area is usually sparse with right whales, we came upon two significant groups of whales engaged in Surface Active Group behavior, rolling, touching, and chasing each other. This behavior is always a treat to see; not only do the whales spend the majority of their time at the surface, as the name of the behavior implies, but the whales splash around a lot, showing us their flippers, tail stocks, chins, heads, and snow white or pitch black bellies. We therefore have the opportunity to collect comprehensive photographic data on the individuals, snapping away at any entanglement or propellor scars that might be in unusual places, documenting the full callosity patterns of the individuals (used for right whale identification), and potentially determining the individuals' genders by photographing their undersides.
Just after we left our second group of right whales we spotted some small, faint spouts and shiny bodies cutting through the enormous swells left over from the storms--a small pod of Rizzo's dolphins! The deep-sea squid eaters are a rarity around here, and everyone onboard was excited about this unusual sighting. These are sizable animals, measuring 10-12 feet in length and weighing up to half a ton. As they came up to breathe, their entire heads would surge out of the water, and we saw their gray, mottled skin and blunt, melon-shaped heads. Later on Saturday as we worked southwards on our second track line we came across a major gathering of whales, easily 25-30 fin and humpback whales and a small collection of right whales. We were in over 600 feet of water, and the echosounder on our vessel was picking up a thick layer of bait fish in the bottom 100 feet below us. We figured the rorquals (e.g., finbacks and humpbacks) were feeding on these bait fish, and the right whales seemed to be traveling through. At this point we were near one of our station tows, and when we performed the tow we brought up only a very slight amount of plankton, meaning that there was nothing obvious in the upper water column for the right whales to be feeding on. On our next two surveys, one Monday and one Tuesday, we collected samples again from this same tow station, both times without getting much plankton in the nets. The humpback and fin whales were in the area on both days, but the right whale sightings there have dwindled. In fact, on Tuesday, we only saw one right whale during the entire cruise! I'm always surprised by how abruptly things change in the ocean. On Monday we saw 7-8 right whales in a particular spot on Jeffrey's, and 24 hours later there wasn't a breath to be seen. However, not seeing whales is as important as seeing whales during research. Discovering where they are is more or less superficial information without being able to compare and contrast these areas of high usage to other areas of low usage.
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After a long barrage of poor weather over the past couple weeks, our stormy November here on the North Shore finally broke for a few days on Saturday, and we took full advantage of the lull to get out surveying. We performed three surveys, in fact, in the past four days, allowing us to cover each of our three track lines at least once and to gather a plankton sample from each of our plankton tows. After a hiatus in survey effort during those storms, it was very interesting to see how the number and location of right whales (as well as some other species) had changed and compare that to how the food resources, in the form of plankton, had also changed. And there was quite a change.
One last fun sighting I want to mention happened on Monday, when we had a Surface Active Group of right whales that included a mother/calf pair and a pod of Atlantic white-sided dolphins. Down off of Georgia and Florida, on the North Atlantic right whale calving grounds, seeing bottlenose dolphins associated with right whales is quite common, though it's unusual to see dolphins associated with large baleen whales up here in these waters. It's interesting, then, to see such an association take place here, as if right whales just tend to have dolphins follow them wherever they go.