12/25/12

Finding Whales in the Outer Fall

As Moe mentioned in the previous blog, we experienced quite a bit of rough weather while surveying the Outer Fall area in the Gulf of Maine. "We were able to maintain a watch during the daylight hours (~9 hours) and during all sea conditions which ranged from Beaufort sea state 2 to 8, and most of that was Beaufort 5 to 6; wind speed of 10 to 35+ knots, and wave heights of 2 to 12 feet!" Thankfully, we all came prepared with our anti-nausea medications and saltine crackers, and after a couple of days we were fairly well adjusted to the rolling of the ship.

Yet, those kind of seas don't just provide uncomfortable working conditions—they also make it extremely difficult to find and follow whales: the revealing blow of a whale gets pushed down by strong wind and dissipates more quickly (making it hard to see in the first place, but it also increases the difficulty of identifying the species); blows and body parts can be hidden in the trough of the waves; white water from a surfacing whale can blend in with the crests of the waves. We had our work cut out for us!

We categorized this sea state as "big."

On our first full survey day, our search in a sea state 7 turned up some dolphins and one unidentified large whale—not exactly how you want to start your research cruise. But our second day seemed more promising; around 11am, we sighted a right whale and decided to follow it. Our plan was to see if it would start feeding, at which point the WHOI team would collect samples to see what it was eating. Over the next several hours, the sea state worsened and the travelling whale always seemed to be out of our reach. Even though the whale did not appear to be feeding, the WHOI team conducted four sampling stations along the way so that they would have some data collected near a right whale. Unable to collect useful photographs by the time the sun set, we had to call it a day.

A fun game, like "Where's Waldo?" Can you find the right whale? Hint: look in the center!

With calmer winds on our third day, our sighting conditions were favorable, and we did see many large whales—fin, humpback and sei! We also had some pods of white-sided dolphins cruise by the vessel. Surveying around the area where the gliders had detected right whales, we were surprised that we only saw one the entire day. This whale seemed to be travelling, as it fluked and was not resighted by the team. As we brought our gear inside at the end of the day, we braced ourselves with the knowledge that the forecast was calling for strong winds the next day. Indeed, the Gulf of Maine showed us how feisty it could be on our fourth survey day. As the R/V Endeavor pushed through a sea state 8 and 36+ knots of wind, the observers on the flybridge experienced light rain and even snow! It should not shock the reader to know that we only saw one unidentified large whale and a few dolphins. The following day, things seemed to have simmered down a bit with a sea state 4 to 6, and we were able to sight a few fin whales.

Suddenly our last survey day was upon us, and we needed it to be a good one! With calmer seas, sighting conditions were favorable, and around 10 am the observers spotted two right whales!

Catalog # 3611 makes an appearance. Photo: Tracy Montgomery

These two whales were hanging out with each other and spending time at the surface, so we were finally able to capture photographs that led us to identify who they were! One of the whales, #3803, is a four year-old female that bears healed propeller scars on her body and head. The other whale was #3611, a six year-old of unknown sex.

Catalog #3611 and #3803 at the surface. Photo: Marianna Hagbloom

As we followed these two whales, we noticed a couple of other right whales in the distance, but we were unable to get close to them. After the WHOI team collected some samples, we motored in the direction of a breaching right whale on the horizon. As we neared where it was last sighted, a right whale breached again, and then began lobtailing—lifting the muscular peduncle and fluke out of the water and slapping it against the surface! It was soon joined by a second right whale, and they engaged in a surface active group (SAG) for over one hour! We were again able to photograph these two whales, and identified them as #3620, a six year-old male, and #3460, an eight year-old male. A third right whale fluked nearby, but it didn't join the SAG. As darkness fell upon us, we said farewell to the pair and all the other right whales that we knew were in the area but were unable to document.

Catalog #3460 and #3620 surfacing together. Photo: Marianna Hagbloom

Our trip into the Outer Fall made it clear why this area is so difficult to survey; our right whale sightings shows us that this area is still promising to be an important winter habitat. While we didn't witness any large aggregations, our survey was early in the winter and the water temperature was relatively warm, so perhaps we were in the right place but at the wrong time. Our team is determined to continue to find inventive ways to brave the winter seas in our quest to learn more about this potential mating ground, so hopefully you'll hear about more adventures like these in the future!

-Marianna

1 comment:

  1. This reminds me of the lookout on the ships bow in dense fog reporting" I can almost see the lighthouse".

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