Friday, September 16, 2011
We had a beautiful day for whale watching offshore. Clear skies and winds out of the southwest. As we headed past Gurnet Point and east towards Stellwagen Bank, we found an active pair of humpback whales just west of the Stellwagen Bank National Marine Sanctuary.
One animal in this pair was breaching clear out of the water. Humpback whales can breach (jump) head first or tail first, often adding a spin or rotation to their movements. This whale was doing a spinning head breach for it was jumping out of the water head first and then spinning in the air before crashing back into the ocean.
The second whale was jumping out of the water tail first in a behavior called tail breaching. Here the whale throws its body out of the water fluke first, but in a more lateral motion. This gave us a chance to see the ventral tail pattern on this animal and we realized that this whale was a humpback whale named Forceps. Forceps then started to lobtail repeatedly. This really gave us a beautiful look at that unique tail (fluke) pattern.
Within minutes of the start of these active behaviors, this pair split up and moved away from each other. We stayed with Forceps for this whale started feeding just beneath the surface. Forceps feeding strategy was fast and rapid. Without warning, the whale would surface showing us expanded ventral pleats under the chin.
This is an indication that the whale just finished a lunge a few feet beneath the surface and was now in the process of straining or pushing the water out. But what the whale was feeding on, eluded our vision. We assume that Forceps was feeding on some type of large Euphausiid like Krill, but we would not see anything in the surface water.
The captain was also curious as to what the whale was feeding on and decided to conduct a plankton tow. We often conduct plankton tows when offshore and our crew members Rich and Ron got right to it. As we moved slowly to stay close to Forceps, we could see the plankton net trailing behind the boat.
On the way home, our passengers were amazed to see all the small zooplankton that we had collected near Forceps. Much of the sample was composed of copepods, the most common type of zooplankton in our area. But I doubt that Forceps was feeding on copepods. I assume that the copepods were the prey for the organisms that Forceps was feeding on. Humpback baleen is more suited for filtering small school fish and larger zooplankton species out of the water. Not something as small as a copepod.
There are large baleen whales that do indeed feed on copepods and the North Atlantic right whale is the whale that first comes to mind. And so once again, we can only surmise what is happening just a few feet beneath the water's surface, nothing more.
We were joined by the Captain Rudy Thomas out of Provincetown, a boat that collaborates with Capt. John. We waved hello to her captain and crew including their naturalist who was onboard for the trip, Leah. We had the Captain Rudy Thomas stay with Forceps while we moved off to find the second humpback that was originally with Forceps. We had never gotten a really good look at this animal's ventral tail pattern, so we were hoping to confirm an ID.
As we slowly approached this animal, we saw bubbles rising off our bow. This whale was using bubble clouds to help it concentrate the prey. As the whale rose through the bubbles, we saw water being pushed out of the animal's mouth. As with Forceps, this whale was lunge feeding just beneath the surface and beginning to strain as it came up for a breath.
This animal arched its back and lifted its fluke high out of the water. A very black tail indeed, with a distinctive band of white markings on the lower left fluke. These distinctive marks helped us to identify this whale as Geometry, a humpback whale that we have been watching offshore for the past week or two.
It was interesting to see how Geometry was using a different technique to feed on the same prey that Forceps was feeding on. A good reminder that humpback whales are unique individuals who have individualistic ways of accomplishing the same thing. We watched Geometry continue to feed using bubble clouds, but kept our eye on Forceps who was just a quarter mile away. Would these two whales join up again?
Well, in less than 20 minutes, we witnessed both whales coming together once more to feed. Geometry continued to create bubble nets, but this time, two whales surfaced in the center as they completed a lunge. Whatever tiff or rift they might have experienced at the beginning of our trip that made them separate appeared to have been mended. They were now feeding together, coordinating their movements like a pair of ballet dancers. If only we really knew what was going on. But it is fun to try and guess!
Another fabulous day offshore with two very endangered humpback whales, Forceps and Geometry. Seabirds included Northern gannets, Wilson's storm petrels, manx shearwaters and greater shearwaters.
12 noon whale watch trip - Sue
12 noon whale watching trip - Krill
We had light southwest winds and relatively calm seas as we headed out of Plymouth Harbor to the southwest corner of Stellwagen Bank. Even before we arrived on the corner, one of our passengers spotted a humpback whale feeding just beneath the water's surface.
As we watched this animal lunge a few feet beneath the surface, we could see how distended the throat area was. Humpback whales are rorquals for they have a series of ventral pleat that expand when the whale feeds.
Expanding pleats allows for more water and bait to enter the mouth which acts like a big trap or bucket. The whale then closes the mouth, but keeps the jaw agape just a bit. Then the water slowly moves through the water and strains, or pushes the water back out.
Whales do not drink salt water, for it would be too taxing on the kidneys. Them marine mammals get all of their fresh water requirements from the fish or zooplankton that they eat.
Finally the humpback lifted its tail out of the water as it went on a deeper dive. That gave us a chance to see the beautiful black & white white ventral tail pattern that is distinctive to each individual humpback whales. Using this pattern we realized that we were watching a humpback whale named Forceps.
Forceps was named for the black mark on the lower right ventral fluke that looks like a pair of forceps. By naming a humpback based on a natural body marking or pigmentation pattern, it is easier to re-identify it and to remember its name.
We have over 2500 humpbacks that have been named in our waters of the western North Atlantic. Captain John Boats is part of this ongoing research program so by joining us offshore, you are supporting whale research and conservation.
We watched Forceps for a while and then decided to move on. Over the VHF radio, our captain heard reports of a finback whale and a minke whale off Race Point. As we headed that way, we saw quite a few herring gulls flying just off our port side. Many people don't like herring gulls since they often feed on human food thrown away in our dumps and in public areas. But they are beautiful birds that really should be appreciated for their many amazing traits.
As we headed south towards the tip of Cape Cod, we saw a red balloon floating down from the sky. It landed in the water just off our port side. Our captain and crew decided to pick it up since balloons and other forms of plastic are one of the biggest hazards to many different types of marine wildlife. Our crew members Ron and Rick did a great job of getting this trash out of the water. And what was fun about this balloon was that it was shaped like a lobster. How fitting for us out on the water.
Even though we scanned the waters off Race Point, we were not able to pick up the finback whale. Finbacks are the second largest of all the baleen whales and one of the fastest whales offshore. However, we were able to get some great looks at a few minke whales that were probably feeding deep in the Race Rip.
Minke whales are a sharp contrast to their larger humpback cousin. These small whales are less than 25 feet and are often "no nonsense" regarding their behaviors offshore. Very infrequently do they come over to boats to give us a close approach, but today we were treated to an amazing look at two individuals who surfaced close to our vessel.
Our captain, Capt. Russ, did an excellent job of giving the animals space so they felt comfortable with our presence and with anticipating where and when the minke whale would come up. In the end, we had some of the nicest looks at minke whales that I have had all season.
After leaving Race Point, we had a little time remaining in our whale watch today so headed back north up the west side of Stellwagen Bank. Half way up the bank, we found another humpback whale, our second for the day. This whale was feeding in a similar fashion to Forceps, but was producing a bubble net to help it concentrate the prey. We assume that both whales were feeding on some type of large zooplankton, possible a type of Euphausiid. But they were feeding deep making it impossible for us to confirm the prey type.
When this humpback fluked out, we saw a very dark tail with some white markings on the left bottom fluke. This was Geometry and we were treated to numerous good looks at his very dark ventral tail pattern. Geometry was born to a mother named Star in 1997. So Geometry is 14 years old.
We assume Geometry is sexually mature since our females humpback whales reach sexual maturing around age 6 or 7. But Geometry still seemed smallish to us in size indicating that he was still young and possibly has some growing to do.
We headed home with high spirits as we sat back and enjoyed the sunny, calm day. The ride was beautiful and the people onboard were lovely. Folks had so many great questions and comments that I wasn't finished making my rounds until we were almost back in the inner harbor. A great day offshore with humpback whales, minke whales and interesting gulls and seabirds.
Humpback whales identified include: Forceps and Geometry. Seabirds identified include: Wilson's storm petrels, Northern gannets (juveniles) and greater shearwaters.