A collaborative study to describe the underwater behavior of humpback whales focused in and around the Stellwagen Bank National Marine Sanctuary.
The past three days we spent out near Chatham, docking there for Thursday and Friday night. When you are out for 12 hour days for many days in a row (I still feel like I am on a rocking boat when I close my eyes), your days tend to mush together…but I will try to sum it up as best as I can.
Thursday we left the Sanctuary dock bright and early and spent 4 hours or so getting back to where the whales (and the Foster) were. Once we found them both, we got Elliot on board to map some prey. We also tried to photo ID as many whales as possible, which really helps to keep track of a tagged animal if it is in a group. Really the girls from the Whale Center were in charge of that but I like to think I helped. We keep track of tagged animals not only by their flukes, but also with a VHF transmitter which beeps every time the tag comes out of the water. Think glorified TV antenna when TV’s used to have antennae. The bad part about the day was that an entangled turtle, humpback, and grey seal were all sighted. The Song of the Whale was dispatched to help out with the turtle, but I never found out how that went. I will report back if I do.
Yesterday we got the luxury of sleeping in and left the harbor at around 0700. Once we found the Foster I was picked up in the Luna and got to learn all about using the laser range finder and behavioral following. I also learned that being surrounded by bubble nets and lunge feeding whales when you are practically eye level with them is just plain amazing, but seeing bubbles coming up right under your tiny little RHIB is quite frightening…but still pretty neat. The tagged animal we followed in the Luna ended up keeping her DTAG on for a record 24 hours, the maximum time it was programmed for. So I also got to see the retrieval of said tag.
Today was by far the best day of the trip though. Once underway, we received instruction from Dave to, and I quote, find the mother lode. Of whales that is. So after searching around for a while and following a few different groups, we noticed that they all seemed to be headed in the same direction. Naturally, we followed. Suddenly (or so it seemed) we were surrounded. Humpbacks and minke whales everywhere you looked, in any direction. Some were as close as a couple hundred meters and some as far as a kilometer or more. We had found the mother lode. They weren’t just lazing around either, they were breaching, kick feeding, lunge feeding…there were bubble nets everywhere, and some with more than 9 animals to the same net! As Captain Bob says, no refunds today! We had to leave a bit earlier than we would have liked in order to make our 4-hour trek back to Scituate, but before we left they got a tag on a female whose calf just happened to be the one that I got several wonderful photos of. Elliot also hopped on board for a bit to get some good data on all that prey swimming about. We managed to leave just in time to pass through a lovely thunderstorm on our way home, complete with lightning and 5ft. seas. Quite the experience.
So the Auk is officially done with her part of the cruise. Good luck to everyone still out on the Foster and Song of the Whale! Hopefully I will be back next year!
Oh that’s right, they are still down south where we left them. So yesterday we stayed around Stellwagen hoping to find some whales, but alas there were only a few loners and a couple mom/calf pairs. One of the goals is to tag a mom, but one of the females we found was very emaciated and her calf didn’t look too great either. Definitely not a candidate for tagging…also definitely not worth the trip up here for the Foster when there are so many whales to choose from where we left her. They even managed to tag a whale with both a DTAG and a Crittercam!
Today though the Foster came to Stellwagen anyway in a last ditch effort to find some whales here. It is, after all, the proposed site of the study. Unfortunately, the whales still don’t agree that it is the place to be. Tomorrow we are both headed back south and we will likely spend two nights moored in Chatham to be closer to the action. I did spot a pair of basking sharks and we got to go over and take a closer look. Half the length of the boat and mouths wide open to filter feed, they were quite the sight.
The Auk left the dock this morning at 0630 to rendezvous with the Foster on Stellwagen Bank. Unfortunately, the whales had other ideas on where they wanted to be today… and apparently we didn’t get the memo. The Foster was unable to move for a bit (a right whale decided now was a good time to snuggle the ship), so we were sent off to find where all the whales had gone. Four hours and many miles later…we found them. We had to go past Cape Cod Bay, around Provincetown, and back south down towards Chatham, but we found them. There were a good 20-25 whales or so feeding in small groups, just the right criteria for tagging. We stayed with the whales until the Foster arrived, but soon after we already had to head home. We had a nice long 4-hour ride back to Scituate to make.
The water was a little too choppy yet again today, so Elliot didn’t make it over to calibrate. Maybe tomorrow…The tagging team had some success at least. They managed to get a couple of tags on, though I think one of them was breached off fairly quickly. It’s only day one, so there will be (hopefully) plenty more chances.
There is some concern that if the whales stay where they are, they may be too far away for the Auk to be useful. An 8-hour transit time for 4 hours of searching for and following whales is not the most ideal situation. One idea is to dock in Chatham for the night, but I guess it all depends on what the whales do tomorrow. If only they’d cooperate!
Well, because of the wind and the inevitable waves that resulted we couldn’t do any calibration today. Elliot (in charge of this portion of the project) said it will just have to wait until tomorrow. Even though he is staying on the Foster, he will be transported to the Auk daily to do the prey mapping. Hopefully there is better weather on Monday, the first official day of the cruise, and we can get it done before anything too exciting happens.
I did learn a little about echosounders today and the process of prey mapping, but since it is better explained by someone who actually knows what they are doing, here is more information taken from the 2010 blog:
The acoustic echosounder is towed through the water a little beneath the surface as the ship moves around. The echosounders send out short pulses (or pings like on a submarine in a WWII movie) and then record the echoes that come back to the instrument. This is the same technology that governs how a fish finder or depth sounder on a boat works. However ours are a bit higher tech and can provide us some additional information. If there are enough copepods in the water column, then we can see their echoes on our screeen and can tell (in some cases) how many animals there are (number of animals per cubic meter) and where they’re at (near the surface, near the bottom, or moving from one spot to another). -Joe
I arrived in lovely Scituate, Massachusetts today to work with NOAA and the National Marine Sanctuaries for a week on their two-week research project.
The mission: describe underwater behavior of humpback whales.
The method: attach digital recording tags (DTAGs) to humpback whales to record audio, pitch, roll, heading and depth and Crittercams to record video.
The location: Stellwagen Bank National Marine Sanctuary and Jeffreys Ledge.
The boats: the R/V Nancy Foster and her two RHIBS: the Balena and the Luna, the R/V Auk, the S/V Song of the Whale.
The obstacle: not so simple a task.
DTAGs are amazing little devices that attach to a whale with suction cups, and provided they aren’t knocked off can provide hours of valuable data (more information).To get one on however requires some skilled driving in a RHIB (rigid-hulled inflatable boat) and some skilled use of a giant pole with the tag on the end. The same goes for attaching the Crittercams, which can actually show us what goes on when these whales are underwater, and from their point of view (more information). Aside from tagging, we will also be doing some prey mapping to better understand the feeding behavior as well. That part will be done with the help of the Auk, the vessel I will be working on. Tomorrow I get to help calibrate the echosounder and learn about how it works, so more on that soon!
Image taken from Google Maps