“The CTD is the key to understanding the physics, chemistry, and biology of the water column” -NOAA Website
I recently returned from a 3-week jaunt in the Labrador Sea. I was part of an AZOMP research voyage. AZOMP is the acronym for Atlantic Zone Offshore Monitoring Program, a multinational attempt, through annual repetition of oceanographic data collection at particular “stations”, to get a sense of what is happening in the world’s oceans. Canada’s commitment has been considerable – but appropriate given the length of our coastline and the integral importance of the ocean to our health, economy, and well-being.
The CTD (Conductivity, Temperature, and Depth) ready to be lowered to the sea bottom. Each bottle is preset to open at a particular depth to capture a water sample at that depth. -DOL
As the “O” would indicate, this particular aspect of the research concentrates on the offshore areas of the North Atlantic – particularly the Labrador Sea, the body of water between Labrador and Greenland. My role, as “seabird observer”, is to position myself on the bridge so I can see the open ocean ahead and to one side of the vessel and count seabirds (in fact, any birds…as you will see) and marine mammals. The day runs from first light until last light and can be quite physically grueling – thank goodness it’s so interesting! You just never know what you’re going to see…..or where. You can think of birds as sentinels. They are easily visible and their presence and number at a particular site can be an indicator of the health and wealth of the food chain there. Changes in the physical and chemical make-up of the ocean and the accompanying food chain associated with it is often reflected in the birds present.
Here’s a few of those sightings, most from the middle of the Labrador Sea:
• On May 29th we were stopped at a sampling station almost right in the middle with over 3400 m of ocean beneath us. (When we’re stopped I often do “stationary counts” on one side of the vessel about every 45 minutes.) There were a lot of Northern Fulmars sitting /flying behind the ship – they think we’re a fishing vessel and are looking for an easy meal. But on the port side a small, very handsome gull was sitting by itself. Close scrutiny showed it to be a Sabine’s Gull in fine breeding (or alternate) plumage. [This species nests in the high Canadian Arctic or on the coast of Greenland and this particular bird probably spent the winter off the SW coast of Africa. I say “probably” because studies using data loggers have shown that some Canadian Arctic birds may go to SW Africa or to the coast of Chile to spend the Winter. In fact, in one interesting study, a pair on a high Arctic island that had nested successfully, split up with one bird going to Africa and the other to Chile. They evidently reunited the very next Summer! I wonder if love made the heart grow stronger…..] After sitting for awhile the gull joined the fulmars flying behind the ship where its aerial dexterity reminded one of a tern. So graceful!
• Gulls were few and far between well offshore….except for Black-legged Kittiwakes, a truly pelagic bird. And most of those sighted were young, 1st summer birds sporting that diagnostic dark “W” marking on their wings – very handsome. (Most adults would be confined to areas close to shore as they would be nesting, sometimes in sizeable colonies.) Quite often these young birds appeared to be playing. I was going to put playing in quotation marks – do birds really play? Well, after watching a number of them over several days, I would say yes, they do. They will chase each other at great speed with diving twists and turns covering 50-100 meters. One will go after another and then, after a long chase, they will reverse roles. And it’s a very useful exercise for them as it seemed that almost wherever I saw kittiwakes I would see jaegers, all 3 varieties (Pomarine, Parasitic, and Long-tailed) in varying numbers, from solitary birds to groups of up to 7. Jaegers are “kleptoparasites”: they chase other seabirds and worry them with aggressive attacks to the point that the victim will disgorge whatever food it is carrying in its crop. The jaeger will then swoop down to recover the “tasty” morsel at the surface – sometimes catching it even before it got there. So, eluding a jaeger attack can be a good skill to have! And a good thing to practice. And why not have fun while you’re doing it? (Would this playing be fun to these young birds? Hmm….
• I saw an interesting twist on this jaeger kleptoparasitism. A jaeger was in hot pursuit of a young kittiwake. The chase went on much longer and over a greater distance than usual. The kittiwake obviously was determined to hold on to whatever tasty morsel it had. The pursuit by the jaeger was vigorous. I noticed a group of fulmars was following the results of the chase….but from below. The birds didn’t follow the up and down gyrations of the gull but managed to stay beneath the action. They weren’t close to the combatants but always directly underneath. Eventually the gull disgorged what it was carrying and before the jaeger could swoop in to grab it, a fulmar, perfectly placed to do so, snatched it up from the surface and took off. The jaeger gave short chase and then broke it off; the fulmar was a much bigger quarry to harry. Smart move by the fulmars. It makes one ponder the learning process by the fulmars that went into this: recognizing the chase for what it was and understanding where/how to take advantage of the probable result.
• It’s not uncommon to see small passerines well out to sea. I’ve seen many, birds that are either confused or have been blown away from the coast or, if crossing open stretches of ocean as part of their normal migration, have got “lost” in fog or overcome by adverse winds. Usually they take refuge, or at least a rest, on the ship. But on May 30th I watched as an American Pipit passed by about 30 meters off the port side. It made no effort to check out the ship or take refuge or a rest. It was on its way, flying ENE with a light quartering SSE wind. We were moving at about 10 knots (nautical miles per hour) so this bird had to be doing at least 12-13 knots, probably more. At this point (59.99669 degrees N; -48.94057 W) it was about 390 NM from Labrador and 105 NM from Greenland which it would reach in another 7-9 hours. American Pipits are uncommon nesting birds on the Greenland coast. Sometimes I’ll see them mixed in with Snow Buntings as they cross.
• On May 30th, about 60 NM off the Greenland coast, a Peregrine Falcon came to check us out and, after circling the vessel a couple of times, flew off. Unlike most raptors, Peregrines aren’t fazed by open water and I’ve seen them quite a few times well off the coast. And there are many reports of them making long crossings of open ocean. They have adapted to this by being able to catch and consume birds as they fly. (In one dramatic instance of this, I watched one cruise down to the surface well out over the mouth of the Bay of Fundy, snatch up a Red Phalarope, and continue on its way, plucking and consuming the hapless phalarope.) This bird would likely have tried to pick off the pipit if it came upon it – or any other passerine that was making the crossing (Snow Buntings do regularly). But my hunch is that its main prey well offshore is the phalarope. Phalaropes are seen regularly 100’s of kilometers from the coast where they take advantage of zooplankton blooms to fuel their journey north (or south). They are true pelagic birds even though you find them in guide books mixed in with the “shorebird” section.
• On June 2nd, even closer to the Greenland coast, 3 female Snow Buntings alit on the foredeck. From there they flew around the ship a couple of times and then….I didn’t seem again; supposedly they had continued on their way to nesting sites in Greenland. We know that many birds that we see (and band) in southern Ontario and Quebec nest in Greenland so they regularly cross the Labrador Sea. We also know that males precede the females by 4-6 weeks in order to establish nesting territories that would attract these females. It’s interesting to me to ponder how the crossing of such a long, inhospitable stretch of ocean became established in this species’ DNA
• Shortly after seeing these Snow Buntings, as we were headed back toward Canada, we came upon a small group of whales. (Whenever possible, we try to keep track of whale/dolphin/seal sightings and, if possible, identify them.) I had never seen Northern Bottlenose Whales before this trip but, on the Greenland side of the Sea, I saw a number. The main pod consisted of 4 individuals. They weren’t particularly concerned about the presence of the ship and, in fact, approached to within about 50 meters of it on the port side. But what was really interesting was the very near approach of a Bottlenose Whale on the starboard side (in fact, it went under the nose) closely accompanied by a Killer Whale! My first thought was YIKES!! Was I about to witness a ghastly predation event on the high seas!? But the Bottlenose Whale it was following didn’t seem concerned in the least and the pod of 4, which was nearby, didn’t show any signs of anxiety or of wanting to escape. I’m wondering if this lone Killer Whale (from the dorsal fin I was able to establish that it was a male) had joined this group simply for social interaction. They are a sociable whale and it seemed to be among friends…..
• On the way back to Labrador, about halfway in fact, I watched a female Common Eider go winging by, due W. It’s well known that many Common Eiders that nest in Arctic Canada spend the Winter in the Open Water area off the Greenland coast, so the passage of this bird shouldn’t have been abnormal. But seeing it, speeding by and alone, certainly surprised me.
These are just a few of the highlights. There’s simply so much to see….
Rick
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