- Research & Education
- Cape Cod
June 12 was gray and foggy with low visibility throughout the day. The seas were calm and the winds were virtually non-existent, so we had a comfortable ride out to Stellwagen Bank. Despite the fog, we encountered a group of 5 humpback whales approximately one hour into the afternoon trip. Parens, Barb, Putter, Flounder and Milkweed were engaging in long dives, and we had to listen for their loud exhalations to find them once they surfaced. After spending about a half an hour hot on their trial, we decided to do some exploring and set off to the north.
Our adventurous spirit paid off once we heard the sound of a humpback whale flippering. The air was so still today that we could hear sound travel for miles, and the sound of a humpback whale’s 15-foot flipper hitting the water’s surface is extremely distinctive! As we approached, we could see this enormous white flipper extended perpendicular to the water, waving and finally colliding with the water. Passengers often wonder if this behavior is directed at the boat, but more likely it is some sort of communication directed at other humpbacks in the area. In the dark, murky waters of the Gulf of Maine, marine animals need to rely on other senses besides their sense of sight. As sound travels better than light in water, it is likely that these animals rely very heavily on acoustics in their daily lives.
The gray skies persisted on to June 13th, but we were able to travel to the same area to find a whole new group of humpbacks east of Stellwagen Bank in an area known as the Triangle. Joined by her calf, as well as a third adult humpback, Cajun spent much of the morning kick-feeding, or using her powerful tail to stun and scare fish so that she could easily lunge through a dense school of them and swallow them whole.
As one of our humpbacks left the area and another, small humpback joined the feasting Cajun, so did a colossal pod of Atlantic white-sided dolphins! Naturalist Mark Gilmore estimated there to be at least 400 individuals in the group!
As the dolphins and the humpbacks charged and fed, the skies were just as exciting. This week we started to notice the return of some of our pelagic migratory birds. The sooty shearwater is known to have one of the longest migration of any other animal. In the Pacific Ocean, these birds are known to travel a distance of 40,000 miles a year, making a figure 8 pattern spanning both the northern and southern hemispheres. They visit Stellwagen Bank for the same reason the whales do – to feed on the enormous schools of small schooling fish.
When we arrived on Stellwagen Bank on June 14th we once again found ourselves surrounded by fog. With less than a quarter mile of visibility, we knew it was going to be difficult to find whales. On a day like today, we often have to rely on our ears, rather than our eyes, to find whales. The air in a whales lungs is under a lot of pressure, so when a whale exhales, it makes a very distinct whooshing noise, just like when you open a can of soda – except louder! After stopping and listening several times, we finally hit the jackpot. 6 humpback whales were found kick feeding and lunge feeding! Through the gray mist we could see the whales slapping the water to scare the fish, then lunging through their prey with an open mouth, emerging with a mouth filled with food and water.
The feeding continued for the next few hours so that even the mid-day and early afternoon trips could find the whales in the fog! By the time the late afternoon trip arrived at Stellwagen Bank, the fog had cleared, we could see for miles, and we were able to locate our whale the old fashioned way — by looking for their spouts. We found Cajun and calf, Jabiru, Freefall, Cajun and Milkweed, who had been feeding earlier in the day. While the feeding bout had ended, we did get to watch Cajun’s calf rolling around, slapping its little flipper down on the water. 3 more humpbacks were seen that afternoon, including Whisk and her calf, as well as a third, unidentified humpback who was also rolling and flipper slapping. After a morning of heavy fog, a trip under clear skies was quite the relief!
By June 15th, we finally had bright sunshine for our whale watching excursions and we headed for Stellwagen Bank to find a number of new humpbacks had moved into the area. Reaper and her fourth calf traveled eastward, toward another mother and calf pair ahead. As they traveled along side our boat, we saw a big splash ahead of us. Perseid’s calf was breaching and lobtailing! Perseid’s calf, despite its small size, is an independent little whale, and often stray from its mother’s side to engage in playful behaviors like this.
In the afternoon, humpback mom and calf pairs still dominated the scene. The highlight of the afternoon trip was watching Whisk roll around on her back, raising her 15 foot flipper into the air, and watching her calf her calf follow suit! Whisk’s calf rolled and wobbled, but couldn’t quite get that flipper to stay up in the air like mom!
The beautiful weather continued on into June 16th and so did the exciting whale sightings! On the morning trip aboard the Portuguese Princess II we saw four different species of cetacean. A fin whale cruised off the beaches of North Truro and humpback whales had clearly located the motherlode of sand lance! Within a mile radius, we had at least fifteen different humpbacks kick feeding, blowing bubbles, and lunging through the gigantic schools of fish they had corralled. Sloop, a female humpback, quickly became our favorite to watch because she feeds with her whole body, first slamming down her chin, followed by a kick of a tail. The finale occurs when she rises up through the bubble cloud she has created with a mouthful of food!
Amidst this feeding frenzy, dolphins leaped through the waves and seemed to be charging at the same food source that the humpbacks were after. Minke whales were also spotted, quickly breaking the surface with their pointed rostrum.
By the afternoon, the skies had clouded over and the feeding frenzy had subsided (this often happens with the change in tide), but a huge aggregation of humpbacks were still occupying the same area just east of Stellwagen Bank. As the adults humpbacks went on long, deep dives, presumably to forage for food closer to the ocean floor, some of the calves became restless at the surface. The wind picked up, and we wondered if this was going to spark a change in the whale’s behavior, as it often does. As we suspected, the calves began to breach. We counted four calves in the group – Cajun’s calf, Perseid’s calf, Whisk’s calf, and one unidentified calf – and they all breached over and over again! When a lull in the breaching occurred, the stillness would be rapidly broken by a calf smacking its tail or slapping its flipper.
We don’t know why humpbacks engage in these dramatic behaviors, but when we have multiple calves engaging in them at one time, we suspect that it’s probably playful. The wind continue to pick up, and it started to rain, so we headed back to shore with the calves still jumping behind us. We remarked that we had never had a trip like that before!
June 17th was gray. but still calm and clear, and we decided to head up to the center of Stellwagen Bank to see what was new in that area. We were thrilled to spot the telltale white-streaked dorsal fin of our favorite humpback, Salt. We’ve been watching Salt ever since 1975 and this year she is back with her 12th known calf, Zelle. Zelle is named after a high-quality salt mined from peat. Many of Salt’s calves are given “salty” “savory” names to remind us where they came from. Mostaza, Wasabi, Crystal and Soya are all Salt’s calves from previous years. Some of Salt’s calves even have calves of their own!
We suspected from their behavior that Zelle was nursing. Like all mammals, humpbacks nurse their young. We can sometimes tell this is happening when a humpback calf will swim back and forth underneath mom, alternating the side on which it surfaces. A humpback mother has to balance the task of feeding her calf while making sure she eats enough to replenish her energy stores. After all, in the process of giving birth and nursing, she might lose up to 1/3 of her body weight! After yesterday’s feeding frenzy, Salt was clearly up to the task.
By June 18th the whales had dispersed a bit and we had to do a bit more exploring before we finally found whales off the beaches of North Truro. The wind was blowing in such a direction that we could smell the tangy scent of the scrub pine from the Truro woods. An enormous fin whale made an appearance, and we identified it as a whale named Tracks, named for the distinctive propeller scar lining its right side. A humpback mother and calf also appeared, although we were unable to make a positive ID as to their identity. The true highlight of the afternoon was the pod of 30-40 Atlantic white-sided dolphins that we saw at the very end of our trip. Amidst the pod, there was the tiniest dolphin calf, sticking close to its mothers side! These dolphins leaped and surfed in our wake, but we kept a close eye on that mom and calf, and finally got a great photo, despite their stealth and quick movements!