July 26th was sunny and hazy, and it felt great to be out on the water heading towards Stellwagen Bank. Stellwagen Bank, part of the only national marine sanctuary in New England, is home to a wide variety of whales, fish, birds, invertebrates. It is here that cold, nutrient-rich currents from the north collide with underwater obstructions, such as the side of Stellwagen Bank itself, to create upwellings. Upwellings are filled with circulating nutrients, and tend to be where all sorts of animals congregate in their search for food (or as they become food for another!). The Boston Globe recently published an article on the sanctuary and some of the protective measures conservation groups and regulators are taking to conserve some of the wildlife in the bank. Read the article here to learn more.
Provincetown is the closest port to Stellwagen Bank, and so it didn’t take long before we were seeing wildlife of all varieties, starting with a gray seal, spotted chowing down on a huge bluefish right off of Herring Cove Beach in Provincetown! As we made our way further north, humpback whales and dolphins were spotted throughout the trip, starting with a humpback whale named Reflection. Reflection is a female humpback named for the mirror image-like pattern on her fluke.
Humpbacks are named for the markings on the undersides of their tail, their dorsal fins, or any other unique features of their bodies. The inspiration for this naming system came from a humpback whale named Salt. She was named by a Dolphin Fleet Whale Watch captain in 1975 because the white markings on her dorsal fin made it look like someone had sprinkled salt on her back. Later in the day, the Dolphin VIII actually spotted Salt, who is remarkably still here after all these years – this year with a calf in tow!
Speaking of calves, on July 27th, we were able to identify one of last year’s calves who has made it through the winter to return to its matrilineal feeding ground. Ivory’s calf from 2009 was spotted with an adult humpback, Elephant, to the northeast of Stellwagen Bank. Humpback whale calves will remain with their mothers for an average of one year, but just like with humans, there can be some degree of variability as to when a calf becomes fully independent from its mother. In some cases, we’ll see calves become fully independent while they are still with their mothers in the feeding ground. In other cases, calves will return to the breeding grounds with their mothers in the winter, and remain with them until their return northward in the spring.
We wait for this springtime return before we consider giving the young humpback a name. Now that we have documented Ivory’s ’09 calf, this animal will get a name in the spring of 2012, when scientists from the greater Gulf of Maine will vote on a name which reflects the natural markings on the whale’s tail.
On June 28th, only the morning boat made it out to Stellwagen Bank, as the rest of the day was cancelled due to high winds and rough seas. Despite these rough conditions, we were able to locate Milkweed, Pele, Cajun and her calf, who have been consistently delighting Dolphin Fleet whale watchers for the past month. Sure enough, Cajun’s calf, seemingly riled up by the high winds, breached over and over again.
Cajun’s calf appears to be growing up healthy and quickly. On every trip he or she (the sex has not yet been determined) looks bigger and stronger. Cajun’s calf is very active and will frequently roll around, slap its flipper, or breach, especially in rougher seas!
Calves will often play at the surface while its mother spends time foraging for food on the ocean floor. This seemed to be happening on July 29th, when naturalists aboard the Dolphin VIII and Portuguese Princess suspected that humpbacks were sub-surface feeding all day. Although we can’t be entirely sure what our humpbacks are up to as we wait for them to emerge from the depths, there are certain clues that we look for. Humpbacks feeding at depth will often go for dives exceeding 10 minutes, finally surfacing with their ventral pleats distended, indicating a mouth full of food.
They will also sometimes come up with raw wounds on their jaws, sustained while foraging on the ocean floor. Their main source of food in Stellwagen Bank is the sand lance, a small schooling fish named for its tendency to bury itself in the sand. Humpbacks know this and will often head right down to the bottom and use their jaw to disturb the ocean floor, causing the fish to rush out of the sand and into their wide open mouths!
On June 30, more humpbacks had made their way to the southeast corner of Stellwagen Bank, including Canopy, Springboard and Mostaza. Having seen Salt and her calf earlier in the week, we were especially excited to see Mostaza return to the area, as Mostaza is one of Salt’s calves from 10 years ago!
While watching whales in close proximity, our crew always has our eyes trained to a wider swath of sea, checking out other animals that might be in the area. Looking through his binoculars, our captain, Todd, exclaimed, “Look out at 11 o’clock! Those whales are going to breach!” Sure enough, in the distance, we saw two large adult humpbacks breach, one after the other! Many times, breaching is completely unpredictable, but sometimes we can tell they are going to do it when they dive more rapidly than normal. This is what we call a wind up!
So far this year, scientists in the Gulf of Maine have observed 34 different humpback whale females returning with a calf. On July 1st, we observed one of these new arrivals from the Dolphin VIII. Orbit’s calf provided the finale to our morning trip by breaching repeatedly while its mother, first seen in 1979, was down on deep dives. The small calf would wind up for a breach by first peering up out of the water in a mini-spyhop, then diving quickly and jumping out of the water.
Returning to the same area later in the day, we came across a whale named Venom, named for the markings on the underside of the tail which resemble fangs dripping with Venom. Last year, Venom was spotted with very gray skin, which is a sign of poor health for whales. Naturalists and scientists worried that Venom was getting very ill, and became alarmed when part of her fluke actually came off, apparently as a result of this infection. This year, however, we are happy to report that this 14 year old female is looking a lot healthier. Her skin is dark and healthy-looking, and she is feeding and socializing with other whales. Although part of her fluke is missing, we are more optimistic about her survival, and are always happy to see her here in the feeding ground.
On July 2nd we were excited to see that one of our humpbacks, Reflection, had found a patch of food at the surface, meaning that we could all get a chance to see her feeding. The small schooling fish upon which the whales feed move up and down in the water column depending on tide, temperature, and light levels. Humpbacks will pursue them and eat them at whatever depth, shallow or deep, that they can find them. Today, Reflection lunged through a school of fish, mouth agape, aggregating the fish in her reservoir-like lower jaw before pushing the salt water out between her baleen plates and trapping the fish behind the fibers of the baleen.
Later, we found Orbit and her calf back in action. Orbit’s calf was rolling on its side, flipper in the air. Orbit’s calf was energetic throughout the day and continued to breach and flipper into the afternoon. As if that wasn’t enough excitement, a small pod of Atlantic white-sided dolphins made an appearance on several of the trips as well.
Over the course of the day, a total of four different cetaceans were spotted, including a Minke whale, and even an enormous fin whale. As we enter into July, we are excited for what the rest of the summer will bring!