From a pelagic birder's perspective, this journey feels as if it is divided into three legs: the Beagle Channel/inshore South Atlantic, the Drake Passage, and Antarctica. Though there is overlap, each of those three segments has its own vibe and wildlife diversity that is different than the others. Here I am combining both the outgoing and return journeys through the Beagle and the Drake. Antarctica itself deserves its own post.
In the weeks leading up to the trip, as I was telling friends and family where we were headed, the one question I received the most was "don't you have to sail through the roughest waters in the world to get there?" Even to the uninitiated, the Drake Passage is famous for its volatility. Depending on the weather, you might be greeted with the feared "Drake Shake." But if you're living right, you'll get the "Drake Lake." We were lucky in that our seas were light to moderate. Not exactly a lake, but the shaking was tolerable. At its calmest, we felt a gentle rock. At its peak, it was difficult to lie down without getting rolled a bit. But not terrible. The ship's flu-like illness might have struck us, but thankfully seasickness did not add insult to injury.
The seabirds came in pulses, as they often do. The continental slopes, known for their upwelling, were the birdiest. The Drake Passage itself felt barren at times, but even those moments held a few birds scattered here and there. Never did I find myself bored, as the dull stretches were buoyed by the "any second now" anticipation that is provided by pelagic birding in a new part of the world.
My time spent in the southern oceans has admittedly been limited for someone who enjoys seabirding as much as I do. Over 20 years ago I spent some time offshore Australia and New Zealand, and I took one pelagic when I returned to Oz several years ago with my buddy Ian. But that's been about it. No Humboldt Current or Cape Town pelagic yet. No Flock to Marion. No Atlantic nor Pacific Odyssey. No 'Around the Horn' repo cruise. And, until now, no Antarctica.
That is not meant to be a complaint. I've had a ton of great experiences on the water and am very lucky to have done all that. What I'm trying to say is that I had some killer life birds on the table here! In fact, Light-mantled Albatross was perhaps my most-wanted bird in the world going into this trip. No matter what, I would go home a happy seabirder.
From north to south, from the Beagle Channel to the continental slope of Antarctica, here is what we encountered.
The Beagle Channel itself is not open ocean and is not terribly wide. Still, a few seabirds are common throughout. CHILEAN SKUA, BLACK-BROWED ALBATROSS, SOUTHERN GIANT-PETREL, and SOUTHERN FULMAR are all easy to see in the Channel itself, even from land. MAGELLANIC and GENTOO PENGUINS breed here and are sometimes seen swimming and porpoising, especially in calm conditions. SOUTH AMERICAN TERN is the only expected tern species and is common to abundant. MAGELLANIC DIVING-PETREL used to be expected in these waters but has become quite scarce over the past couple decades. We dipped on that bird in
2022, and I missed it again this time! As far as mammals go, SOUTH AMERICAN SEA LION seems to be the one you're most likely to encounter in the channel.
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| Southern Fulmar |
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| Southern Fulmar |
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| Black-browed Albatross |
Seabird diversity is pretty much restricted to those species until you get further east in the Channel. While emerging toward open ocean we began to see numbers of WILSON'S STORM-PETRELS and SOOTY SHEARWATERS.
The local Wilson's Storm-Petrel situation is particularly tricky as far as taxonomy is concerned. A certain percentage of the WISP seen in the Beagle Channel and near Cape Horn are called "Fuegian" and are potentially identified by variably white tips to underwing coverts and sometimes white on the rear belly. As you work further south into the Drake Passage, "Fuegian" is supposedly replaced by your standard WISP that lack white outside of the rump patch. The taxonomy and field ID of the Wilson's Storm-Petrel complex is still very much being worked out. I paid close attention to any WISP I saw and tried to get underside photos of the birds that were close. Sure enough, at least a few petrels close to the South American continent that had a narrow white slash on the underwing. None of the individuals around Antarctica showed this feature; those all looked basically like the birds we see back home during our Northern summer. I'm not really sure what that all means, but I'm looking forward to upcoming literature that might tackle this issue.
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| Wilson's Storm-Petrels showing features consistent with the form currently referred to as "Fuegian" |
We did not see any cetaceans in the Beagle Channel itself, but we had SEI WHALES and both DUSKY and PEALE'S DOLPHINS just east of the channel mouth.
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| Dusky Dolphin |
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| Dusky Dolphin |
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| Sei Whale |
Once off the continental shelf and into the Drake, the birdlife changes again and tubenose diversity really picks up. But more on that later. The thing that surprised me the most was actually penguin diversity in the open ocean here. We crossed paths with three species of penguin in these open waters that we were not guaranteed to see because they do not breed along our route: WESTERN ROCKHOPPER, MACARONI, and KING PENGUINS. I'm not sure if this is typical or if we just got lucky, but these chance encounters boosted our penguin diversity to a whopping eight species.
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| King Penguin |
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| Macaroni Penguin |
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| Western Rockhopper Penguin |
OK, back to birds that can fly. I had a few encounters with DIVING-PETRELS in the northern Drake, two of which were reasonably well-photographed. A few possible species are in play here. I had mentioned previously the chance at Magellanic Diving-Petrel in these waters. That is the easy one to identify. It is a rather high-contrast species that is very blackish above and white below with an obvious white half-collar on its neck. The two birds pictured here are certainly not Magellanic. In the open ocean near Cape Horn, Common Diving-Petrel is the most likely species. And that's what both of these probably are. However, there are confirmed in-hand records of South Georgian Diving-Petrel from the Drake Passage, so they are there too. I've had a more difficult time ruling out that species than I was anticipating.
Common Diving-Petrels average larger and duskier, especially on the underwings. Making things more complicated, both CODP and SGDP have multiple breeding populations that vary in appearance. The taxonomy is far from settled at this point. If these birds had duskier underwings and flanks, and less broad white braces on the topside, I would probably have been fine calling them Commons. But that's not the case. It is possible that the state of molt might help if I dig more on these. For now, they get the slash.
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| diving-petrel sp. |
You're probably wondering about the stars of the show: the albatrosses. We encountered six species in the Drake: SOUTHERN ROYAL, NORTHERN ROYAL (just one), SNOWY (AKA Wandering), LIGHT-MANTLED, GRAY-HEADED, and of course BLACK-BROWED.
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| Gray-headed Albatross |
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| Black-browed Albatross |
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| Light-mantled Albatross |
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| Light-mantled Albatross |
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| "Wandering" Albatross, most likely Snowy by range |
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| Southern Royal Albatross |
If any species dominates these waters in numbers, it is the BLUE PETREL. They are very prion-like, but with convenient stark white tail tips and strong head patterns that aid in separation from those headache-inducing prions.
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| Blue Petrels |
Speaking of, we saw the two expected species, SLENDER-BILLED (northern Drake) and ANTARCTIC PRIONS (further south). It's possible that we had more than two taxa, but their identification and taxonomy is about as clear as the Wilson's Petrels. This was my first go at prion ID, and they lived up to their difficult reputation.
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| Two prion taxa here, I think. Slender-billed at right. The bird at left is different in several ways (face pattern, bill shape, tail pattern, wing pattern) and might be Antarctic, though it has a bit more white on the face and a thinner bill than the Antarctics we saw further south. |
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| Antarctic Prion |
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| Antarctic Prion |
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| Antarctic Prion |
PINTADO PETRELS were not terribly common in the northern part of the passage but became more common further south. WHITE-CHINNED PETRELS were reversed, being more abundant to the north.
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| Pintado Petrel |
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| White-chinned Petrel |
One of my most-anticipated and favorite seabirds of the trip was BLACK-BELLIED STORM-PETREL. I was incredibly stoked to observe their leg-dragging behavior as they whipped between large Southern Ocean waves in a hard wind. Those of you who have spent time on the ocean know what I mean...when you're facing into a strong wind, barely able to keep yourself still, you brace yourself against the rail and wonder how an 8-inch long bird can make air travel look that easy as it effortlessly drags one foot across the water's surface.
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| Black-bellied Storm-Petrel |
SOUTHERN GIANT-PETRELS were a mainstay for the entire cruise, from the Beagle all the way to the White Continent and back. NORTHERN GIANT-PETRELS were very scarce; I only had a few confirmed for the entire trip.
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| Southern Giant-Petrel |
The Drake Passage itself didn't hold many cetaceans for us, but the species I did see well was a great one. Out of nowhere a few HOURGLASS DOLPHINS appeared in our wake and disappeared as quickly as they came. Second favorite mammal sighting of the trip!
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| Hourglass Dolphins |
- NB
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