Daily Blog: Antarctic killer whale field research, January-February 2012

Antarctic killer whale research

Watch video from last year's expedition aboard the M/V National Geographic Explorer

 

SWFSC scientists John Durban and Bob Pitman deploying a satellite tag on a killer whale during the current field season onboard the National Geographic explorer with Lindblad Expeditions. Photo by Doug Gualteri

SWFSC Scientists John Durban (left) and Bob Pitman (right).  Leopard seal on ice in background. Photo by Birgit Buhleier

  

2012 Blog

13 February, 2012
Our last day in Antarctica this season, and our last chance to put some runs on the scoreboard. The morning was devoted to the obligatory retail frenzy at Port Lockroy, resulting in armloads of t-shirts and trinkets making their way back to the ship. Penguins, skuas and sheathbills all nest immediately off the walkways around the buildings at Lockroy; long since habituated to the foot traffic of 1000s of tourists every season, they go about their business completely oblivious to our presence. It’s a great opportunity to view undisturbed wildlife and perennial favorite among the passengers. After lunch, we headed up the scenic Neumeyer Channel and then across the Gerlache Strait to a planned landing site in Paradise Harbor. It was a bright, sunny day with only a couple knots of wind; under those we expect to encounter Gerlache killer whales. And there they were. Due to excellent weather conditions, the captain agreed to deploy our strike team in a Zodiac and return to pick us up in 5 hrs. We rarely get this amount of quality time with killer whales down here – the ship has appointments to keep and some passengers get impatient if we spend too much time with the KWs - but after 6 wks on the ship, and our last day in Antarctica, we finally got the opportunity we wanted. Unfortunately, the whales were just a bit too evasive and we weren’t able to put out a single satellite tag. But we did record some very useful observations on behavior and feeding ecology of this animal. In the Peninsula area, we see killer whales of three very different types (or possibly species). There is type A, which for the most part preys on Antarctic minke whales, and two other, distinctly different types that we initially lumped together as type B killer whales, but which we now know includes a large form and a small form. The large form (pack ice killer whale - PIKW) appears to feed mainly by wave-washing seals off ice floes, and the small form (Gerlache killer whale - GKW) takes penguins occasionally but seems to ignore mammals. We suspect that GKW is a fish-eater, an idea that gained some traction during an earlier trip this season when John put a dive-depth tag on one and it was diving 500 to 600 m, mostly at night, and likely going to or near the bottom. It appeared from the dive behavior we saw today that GKW forages singly and is underwater for long periods of time; the adult males in particular sometimes disappeared for at least 30 min at a time before resurfacing. These data and observations suggest that GKW is ecologically very different from PIKW. The differences in prey preferences alone, and the specific adaptations required to capture those prey, likely means the two forms are physiologically, morphologically, behaviorally, and acoustically distinct - perhaps to the point where interbreeding is avoided or even impossible. It’s been a good season, we have learned a lot, but there are many unanswered questions here.

We thank Lindblad and National Geographic for the opportunity to conduct research on this splendid vessel, and for allowing us to advance killer whale science and conservation in Antarctica. See you next year!
--
Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

12 February, 2012
Today was a good day as we traveled northwards through the pack ice off the west side of the Antarctic Peninsula. The early snow gradually cleared to bright sunshine by the end of the day, and we were treated to spectacular views of the Peninsula's mountain peaks. There are few better days in our office than looking for whales in the ice - you never know when they will appear from behind the ice sculptures, which provide a visual feast even in the absence of whales. Late in the afternoon Bob sighted four humpback whales deep in the ice, visible from miles away as they spy-hopped high to look for the next breathing hole. As we approached slowly in the ship we could hear their bellowing blows carrying far in the calm air. The whales were resting, and moving slowly - a good opportunity for a tag deployments. Fortunately there was enough open water to slowly approach in a zodiac, and we quickly deployed satellite tags on two adult whales. It is hard to convey how massive these whales appear up close, and how loud their blows can sound, particularly when they blow in booming stereo. The tags we deployed today weigh just 49g each; a stark contrast to whales that likely weighed in excess of 40 tons. We hope these small tags prove as successful for large whales as they have for killer whales: our discovery of rapid killer whale migrations to warm water have led us to suggest that the migration of large whales away from high latitude feeding grounds may also be driven, at least partly, by the thermal constraints of regenerating skin in frigid polar waters. Detailed tracks of their migratory movements relative to water temperatures will allow us to investigate this, and we hope our miniature transmitters provide a viable alternative to larger implant-type tags. Time will tell, as we follow the tracks online (/MMTD-KillerWhale-TrackMap/).
--
John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

11 February, 2012 – Pier pressure.
This morning, in thick, heavy snow, we visited Rothera Station, a lonely outpost for British scientific research at the southern end of Adelaide Island. When we attempted to tie up to their dock, the truck tires that they had rigged as bumpers proved inadequate for fending off our ship as it heaved in the heavy swell. There was a great gnashing of metal and a generous exchange of paint as we attempted to park, and we promptly pulled away and anchored out in the bay. Passengers were ferried ashore so they could inspect the facilities, learn about the science done there, and stand in line at the souvenir shop. It turns out that the only thing humans like better than visiting exotic, faraway places is to purchase hats and t-shirts emblazoned with the names of those places. Currently, there are scores of humpback whales summering around southern Adelaide Island, and the feeding must be very good here because some of them appear to be enormously well fed: when they rest at the surface, bloated with krill, their backs are the size of a garage door (2-car!). After lunch we left Rothera and motored north in Laubeuf Fjord again, but only for an hour or so; this was a last-ditch attempt to find some large type B killer whales. It was not meant to be - there is very little pack ice here now and we did not see any ice seals; nothing here for a killer whale that specializes on taking seals off ice floes. Compared to most terrestrial predators, the habitat of ice-inhabiting killer whales is surprisingly unpredictable – an area with dense pack ice and plenty of seals one year can be all open water the following year. Ice-dependent killer whales therefore have to go looking for suitable habitat every year, and due to significant climate warming in this part of Antarctica that generally means pushing further south. Killer whales may live to be over 100 years old, and during their lifetimes the populations here have seen a major decline in ice coverage in this part of Antarctica; maybe we should ask them whether climate change is real or not.
--
Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

10 February, 2012 - Family ties
Today we found a group of killer whales in Laubeuf Fjord - an incredibly scenic body of water separating Adelaide Island from the Antarctic Peninsula, south of the Antarctic circle. We spent a special month here working with the BBC's Frozen Planet film crew in 2009, when we observed the most spectacular pack-ice killer whales (large form of Type B) hunting seals on ice floes. We were hoping for a repeat performance this week, but found the fjord to be entirely free of sea ice and lounging ice seals. Instead, our encounter today was with the small form of type b killer whale that prefers open water, particularly in the area of the Gerlache Strait. We have had few encounters with these "Gerlache killer whales" away from that core area, including a previous run-in with todays group in a similar location in Laubeuf Fjord in 2009. Today only females and calves were present, with no sign of the large adult male that accompanied them three years ago. All data suggest that killer whales around the world have a very similar matrilineal social structure - even adult males stay with their mothers' group for life. They mate with unrelated individuals when different matrilines come together, generally at times of abundant food, but then return to their mothers; "just like Italian men", as one passenger remarked recently. Perhaps the male from this group is different, maybe he is changing his ways in the modern world, but I suspect he was close by impressing possible mates during his temporary absence. Killer whales do family better than we do.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

9 February, 2012
Our weather today was mostly dense overcast and drizzling snowflakes. The ship spent the first half of the day anchored at Cuverville Island with most of the passengers indulging their relentless pursuit of penguins – be careful, even small doses can be addictive. I went to check on some large whale bones reported on the beach there. We are using a drill to extract powder from the bones of large whales that were left on the beaches down here by whalers 50-100 years ago. Judging by the number of bones left behind, fin whales and blue whales used to be common in the Gerlache Strait but the whales and the whalers are long since gone (‘market forces’). If DNA can be extracted from our powder samples (contamination is the big issue), it may be possible to learn more about the genetic diversity of whales that once lived there and what was lost. Humpback whales are still common here though, and their numbers seem to be increasing with the season. Today we approached a group of four (2 cow/calf prs), and they all swam over to our ship where the mothers allowed their young ones to mug interminably for the scores of cameras. (The main new technological innovation on display this year is people holding up their ipads to take pictures – it is point-and-shoot writ awkward). Several satisfied terabytes later, we began our plunge south toward Adelaide Island and Rothera Station (UK). We are in search of killer whales that hunt seals by swimming in formation and creating waves to wash them off ice floes. This is some of the most remarkable animal behavior ever filmed; it will appear in the BBC series Frozen Planet and will be aired on the Discovery Channel next month (March) and is not to be missed. The wave washing segment stars our personal favorites: Fat Boy and the pack ice killer whales (large type B) – sounds like blues band.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

8 February, 2012; Four thousand tons of blubber

This morning we woke to calm seas and bright sunshine in the Drake Passage. The sheltered passages of the South Shetland Islands were insight, and we were beginning to cross the shallowing waters of the Antarctic continental shelf edge. The swell was laying down with every mile and the blows of great whales hung in the air, silhouetted by the dark clouds behind. The abundance of fin whales, humpback whales and even a solitary sei whale indicated the massive productivity of this marine system - we estimate these whales represented a combined 4000 tons of blubber: a krill recycling center with massive capacity. Even hourglass dolphins made an appearance - a rare sighting this far south. Although our killer whale focus is narrow, we don't loose sight of the wonders of Antarctica. We are lucky to be here, but still we need more killer whales to crown our last trip for the season. They are coming.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

3 February, 2012 - Antarctica the Beautiful
The scenery was spectacular here today as we cruised the Errera Channel and Andvord Bay. Glaciers - walls of ice, sometimes extending for miles - stand like frozen rivers flowing out of the mountains but at geological speed. These are solid tsunamis forced downward by their own weight of accumulated snow, toward the sea, and their thundering groans as they slide over the uneven terrain, crack through the cold stillness like sonic booms reverberating in the surrounding mountains. An amazing sound. And where the sheer glacial faces meet the water, they give birth to ice bergs (‘calving’) that can range from house-size (3 bdrm, split-level ranch), to any one of the various New England states. Our passengers were shuttled ashore at Neko Harbor this afternoon, where, for the first time this trip, they could set foot on continental Antarctica. This was the 7th and final continent for quite a few of our guests and the usual crowd pleaser - collect ‘em all! For John and me, we had our first and only encounter with killer whales on this trip – a group of three that was most likely a mother and her two sons, both strapping young bucks, perhaps in their teens or early twenties. We have seen this group during each of the last 4 years we have been down here and they have behaved exactly the same each time; that is, they wanted nothing to do with us. Momma killer whale has to look after her reproductive investments, which meant we weren’t allowed within 100 m. So we took photographs of each to document the encounter and left them to their business. This is, however, a clear indication that we are getting to know the killer whales of the Antarctic Peninsula fairly well and on an individual basis. We think that there are probably about 1000 killer whales in this area, including at least three different types (possibly species). Within the next few years, we expect to produce an accurate estimate of the killer whale population here and clarify how many species (or subspecies) are present. This year we are participating in 4, 10-day cruises to Antarctica on the National Geographic Explorer and this was our last day of trip number 3. Tomorrow the Drake awaits us and the forecast suggests that there is going to be a lot of vertical component to our trip back – so this may be our last report for a couple of days. Happy birthday to William and Best Wishes to Rose.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

2 February, 2012
A slow day for us today, mostly spent in thick driving snow. Not much to report, our work was featured today in an excellent online article.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

1 February, 2012 
We were at Paulet Island this AM - a thriving, knee-high metropolis of 10s of 1000s of Adélie Penguins. It is hard to describe the magnificent squalor of a huge penguin colony. At these larger colonies, the March of the Penguins often organizes into two opposing lanes of flow as individuals trudging out to sea pass by others on their way back to their nests. This is a ritual immediately familiar to all of us: the daily commute; a busy urban scene with the local denizens hustling off to work or back to their homes and families. The only thing missing is a traffic report: “Northbound traffic has been flowing smoothly into the Antarctic Sound this morning, with only one accident reported: an overturned penguin in the center lane with the usual slow-down due to rubber-neckers. And on the Ross Island cut-off, a Sig Alert has been issued due to a jack-knifed minke whale; a clean-up crew on the scene has blocked the number 3 and 4 lanes as they tend to the krill spill – if you are heading back to the colony this morning you might want to try an alternate route until they clear that area.” On the more scientific side, we found a pair of humpback whales at one of our stops in the afternoon. When we approached them in the Zodiac, they were loath to move - victims of an apparent krill overdose - and within minutes John had put a satellite tag on the larger of the two. We are interested to see if our tags work as well on rorquals as they do on killer whales – if so, we may have to expand our franchise. As you might have guessed, we did not see any killer whales today.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

31 January, 2012 - Escort Service
Today we were back on the shelf of the Antarctic continent, specifically around the South Shetland Islands. It was like coming home, but the welcoming party didn't show up. The killer whales we tagged last trip were only 40 miles off, but not close enough to divert our expedition. As a good second, we had a close look at several humpback whales, including a calf, mother and an attendant escort. Some folks onboard thought this third whale was a "nanny", but we think it was a male with other things on his mind. The role of escorts is still the subject of debate: could it be that some males stay with a female for the entire summer feeding season in order to gain her favor during the subsequent winter breeding? The female and her calf could benefit from having an extra pair of one-ton flippers around to swat predatory killer whales in high latitudes, and those males seem to go to great lengths to impress the girls.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

30 January, 2012 - Groundhog Day
After being delayed in Ushuaia for two extra days, we headed out for our third foray into the Drake Passage, and our best transit yet. Hardly a breath of wind in the fabled strait and although killer whales were once again cited for their ‘failure to appear’, we did have our moments. Most interesting were scattered sightings of at least five spectacled porpoise (Phocoena dioptrica); an obscure, very rarely observed denizen of the blustery latitudes between 40-60°S. Their behavior is unobtrusive and normally they disappear with the first whitecap, but if you can get to the Polar Front (ca. 60°S) when the wind is blowing less than 5 kts, they can actually be fairly common if you know what to look for. It is black above and white below, with a sharply demarcated border along the sides. The eye is embedded within the black area but is set off by a thin white circle around it (the ‘spectacles’ – an optical allusion). This is strikingly beautiful animal that only a fortunate few will ever see alive in the wild. The other cetacean event of note was a band of 12-15 Antarctic minke whales (Balaenoptera bonaerensis) that was flushed by our ship during lunch. People with their napkins still tucked in came out to see this galloping herd, rooster-tailing through the water, ahead and alongside the ship. One whale lunged on its side next to the ship and exposed a saffron belly – normally white, the under surface of this animal was coated with thick layer of yellowish-orange diatoms, a type of algae (see John’s photo below). We think that, at least for killer whales, the presence of these diatoms is a clear indication that animals in the freezing waters down here are not shedding their skin as they normally continuously do in warmer waters. (Skin can be replaced only when blood is circulated to the skin surface, but that could result in a serious loss of heat energy in frigid Antarctic waters). We suggested in a recent paper that this might be the reason why at least some types of Antarctic killer whales undergo migrations to tropical waters, and it appears that this proposed ‘physiological maintenance migration’ could also be important for minke whales and perhaps other, larger species of Antarctic whales as well.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

Antarctic minke whale. Photo by John W. Durban

25 January, 2012 - the Drake Passage
The swirling Drake Passage is much more bearable when we leave the Antarctic Peninsula with fresh data in hand. Today, location and dive-depth data were continually streaming in from satellite transmissions from our three active tags on killer whales, two of which were deployed just yesterday (/MMTD-KillerWhale-TrackMap/). Much of our day today was spent exploring these new data, with a huge sense of excitement and satisfaction. In particular, this is the first time we have deployed a depth-recording satellite tag on a killer whale, to try to understand the feeding behavior of Gerlache killer whales. To date we have only seen this small form of Type B killer whale eating penguins on occasion, but they are abundant (several hundred) around the Antarctic Peninsula and clearly require more abundant prey resources. We have suspected that they feed at depth on fish, but have been unable to confirm this. After just two days, the depth tag has already recorded repeated deep-diving (>250m) during nighttime hours, and shallow resting dives during the day. This confirms that they are feeding at depth, almost certainly on fish (and/or possibly squid) that are themselves more accessible at night due to the vertical migration of krill on which they are feeding. Until now there were no recognized fish-eating killer whales on this side of Antarctica - we now have strong evidence to the contrary. This is an important contribution to understanding the marine food web of Antarctica. Fun stuff. Now we have a few days in port, but hope to be back in action early next week.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

24 January, 2012
We visited Port Lockroy in the morning. It is a unique wildlife/shopping experience – a mini- mini-mall with a parking lot full of penguins. All proceeds go to the Antarctic Heritage Trust and their efforts to preserve historical sites in Antarctica, so you can purchase your souvenirs and mail your postcards with a clear conscience. Afterwards we headed up the Neumeyer Channel and back into the Gerlache Strait to see if our killer whales from yesterday might still be about. They were! The weather had abated considerably since yesterday’s encounter, so we sent in the troops. There were a few smallish groups of whales scattered about and when we approached a pod of eight or so, two curious females immediately came over to inspect our Zodiac – John accessorized one with a dive depth tag; the other with a location-only tag ($4500 and $2500, respectively, will that be cash or charge?). These are the Gerlache killer whales - small type Bs. Big type Bs eat seals and take an occasional minke whale, but to date the only prey we have seen small Bs eating are penguins; we suspect, however, that they are primarily fish-eaters (or possibly squid). We have seen Antarctic fur seals, minke whales and, yesterday, a couple of humpbacks racing along with packs of small Bs, sometimes for an hour or more. Presumably these camp followers are finding some feeding opportunities by associating with Gerlache killer whales, but what specific prey they are after is unknown. From the data we obtain from the dive tags, we will learn how deep the killer whales are foraging and if their dive pattern varies throughout the day. We can also overlay that dive data onto a bathymetry (water depth) chart and determine if the whales are feeding near the surface, close to the bottom, or somewhere in between, and if they prefer certain water depths or bottom topography. For example, many marine mammals prefer steeply sloping bottoms – creatures like features. All of this will provide clues about what small type B killer whales are eating. Tonight we venture back out into the Drake, happy and relieved that we were able to put two tags out just hours before departing for Ushuaia: a game-saving, two-run homer in the bottom of the ninth. It is starting to look like another winning season.
--
Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

23 January, 2012
Gerlache killer whales in the Gerlache Strait.

Gerlache killer whale is a common name we have proposed for the small form of Antarctic Type B: the ones with the huge post-ocular eye patch and dark dorsal cape. Instead of appearing black and white, they are two-tone gray; a jazzy looking killer whale that is likely a different species from those found in northern oceans. As far as we know, they are only found around the Antarctic Peninsula, and are very predictably encountered in the Gerlache Strait, about half way down the west side of the Peninsula. Today they were there as advertised - a group of 50-70, right where we left them last trip. In fact, we encountered the same group (with the same distinctive individuals) exactly a year ago, in exactly the same place. It is tempting to consider them "residents", but our satellite tagging work has documented that they traveled to the edge of the tropics in the intervening months - a rapid return migration that they may have completed more than once since last year in order to regenerate skin in warmer waters. Today they were clean gray and white in coloration, with little yellow diatom coverage indicating that they likely just returned with a new paint job. Rough weather today prevented small boat ops and further tag deployments, but we are happy with the photo-identification re-sights; the data are adding up. This was a good day.
--
John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration 

22 January, 2012
Last night we started heading south along the western Antarctic Peninsula toward the Gullet where we hoped to encounter ‘pack ice killer whales’ – the large type B killer whale that is famous for swimming in formation and creating waves to wash seals off ice floes. It wasn’t to be – the whole area north of Adelaide Island was choked with ice so we tucked our tail between our rudders and headed north again toward Crystal Sound. The only cetaceans we saw today were Antarctic minkes and humpback whales, the latter were mostly in pairs, presumably cows with large calves. Shortly after lunch today I was standing on the stern of the ship when a single, fast-charging humpback rolled on its side and lunged at the surface presumably into a swarm of krill, 100 m from the ship. Its left lower jaw arched high up out of the water and as it scooped a mouthful of water the pleated skin in its throat ballooned out and created a space large enough to drive a medium-sized car into. (OK – and a couple bicycles, several boxes of Xmas decorations and a lawn mower). It is hard to imagine how many individual krill it takes to power a humpback whale through an average lifetime. The black and whites are overdue.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

21 January, 2012; The Danko Coast, Antarctic Peninsula
Today the weather and schedule was not on our side. The good news was that we sighted a small group of killer whales in the early morning; the bad news was that our time with them was very limited due to our busy landing schedule and poor visibility. More humpbacks and minkes were sighted, but we spent most of the day in heavy snow and out of action for whale spotting. Nonetheless, we remain very optimistic for this trip: tomorrow we will be south of the Antarctic circle and back near Adelaide Island, the area where we conducted an intensive study of the foraging behavior and prey selectivity of pack ice killer whales - the large and spectacular form of Antarctic type B. Check out the January 2012 issue of Marine Mammal Science; the cover photo is to die for. 

John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

20 January, 2012
We were back in the Weddell Sea this morning, running a slalom course around the huge ice bergs that blockaded the water between us and our first stop - Paulet Island. At Paulet, the air was redolent with the pungent smell of countless thousands of nesting Adélie Penguins that blanket the lower reaches of the island. Adeliés feed mainly on krill: it goes in red and comes out red so that their colonies are often discernible from several miles away by the pink blush on the landscape. When we got up today the sky was blue, the sea was calm and the type b killer whale we tagged last trip was at Devil Island, 40 miles away – with any luck that tag will provide us with several months of detailed movement data. And with a bit more luck, we’ll have 6-8 of those tags swimming around in Antarctic waters before we leave here in mid-February. By then John and I will have put on a thick layer of fat and will be ready to migrate north – just like the humpbacks. No killer whales today.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

19 January,2012. South Shetland Islands
After 40 hours of rolling in the Drake Passage, we arrived back in the Antarctic this morning. The first stop was at the South Shetland Islands, an archipelago offshore of the main Antarctic Peninsula. The normal weather consists of wind, rain, snow, and reduced visibility. Today we were greeted by brisk winds but bright sunshine. The ice-capped islands shone white, while Cape Petrels escorted the National Geographic Explorer into the shelter of the islands. Currents roar through the island passes, and chinstrap penguins rush in groups of thousands back to their breeding colonies, bellies full with krill to feed their young. No killer whales today, but we are back in the right area. A few minkes and dozens of humpback whales kept is occupied. Since we were here last week, the number of humpbacks has clearly increased: they gather in these productive waters as the summer progresses, taking one-ton gulps of krill to add to their seasonal fattening. We are looking for smaller whales whose role is black and white - the ocean's top predator. Tomorrow has promise.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

18 January, 2012
We have a new load of excited passengers onboard as we plunge back into the Drake again on our way south to Antarctica. Today the Drake slumbered as we had 15 kts of wind and a few whitecaps sprinkled over a gently rolling swell. John and I are looking for type D killer whale: the most different-looking killer whale that we know of, with a tiny white eye patch and a large bulbous head. It has been identified alive at sea less than 10 times and 2 of those were in the Drake Passage. It is so distinctive that it has to be a new species but we will need to bring back a snippet of skin to know for sure. But today we saw only a southern bottlenose whale, a fin whale, a pair of probable strap-toothed whales, and a couple gangs of hourglass dolphins; the latter are exquisitely black-and-white-patterned sprites of the Southern Ocean and a good consolation until we find the type D. Tomorrow, we are back into the realm of types A and B killer whales, and the Ds will have to wait until we cross the Drake again. You can run, but you can’t hide.
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

15 January, 2012. The Drake Passage
Today was spent in the Drake Passage, crossing from the Antarctic Peninsula back to southern Argentina. There were occasional glimpses of southern bottlenose whales and humpbacks surfacing among the rolling swells, but in general it was a quiet day of steady northerly progress. Antarctica is completely surrounded by the vast Southern Ocean, and our passage through these rough and unforgiving seas reminds us of the continent's isolation. The tremendous winds, swells and currents were an effective barrier to early explorers for centuries, but are now routinely crossed by adventurous tourists on expedition ships. There they experience the uniqueness of the world below the Antarctic convergence - a hugely productive marine system, leading to a rich feeding environment for marine mammals. But yet these frigid waters present a thermal challenge to killer whales, which are he smallest entirely marine homeotherm to take advantage of these bountiful waters. Our tagging work over the past four years has revealed that Antarctic (Type B) killer whales periodically head to warmer waters, following a similar track to our crossing and beyond to the subtropics. We hypothesize that this is a "maintenance migration" required to regenerate skin without the high cost of heat loss, and perhaps to allow other essential physiological processes. There are both benefits and costs to life in the freezer. By tommorrow night we will be in the Beagle Channel, with our first view of green landscape in 10 days. However, we will be longing for a return to the ice - killer whale country.
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration

14 January, 2012
We spent the morning at Port Lockroy where there is a small post office amidst a thriving penguin colony. While the passengers were ashore dealing with philatelic and photographic temptations, John, Stephanie and I set out in a launch to hunt for humpbacks and minke whales to satellite tag. We haven’t tagged either of those species before, but we are interested to see how our tag performs on them. Our record tag duration for killer whales is 109 days of detailed location data transmitted to us via satellite and we would be very interested in duplicating those results with some baleen whales. However, the two minke whales we found off Lockroy this morning weren’t willing to be part of our experiment. After lunch, the ship weighed anchor and we cruised through the scenic Neumeyer Channel before turning north into the Gerlache Strait where we found a group of 60-70 small type B killer whales. Large type B killer whales feed mainly on seals that they wave-wash off ice floes, but the smaller type B killer whales, which are commonly encountered in the Gerlache Strait, forage quite differently and we assume that they take prey other than seals or whales. We have seen them feeding on penguins at times, (gentoo and chinstrap), but we suspect that they may be mainly fish-eaters, although we have no direct evidence as yet. The Gerlache killer whales often allow us close approach, but on this day they were evasive and we didn’t deploy any tags. We did however photograph most, if not all, of the group, and we recognized numerous individuals from encounters during previous years. John manages to remember nearly every killer whale he has ever seen down here and because we encounter relatively few 'new' individuals these days, we should soon be able to estimate the population sizes for each of the different types (or species) of killer whales that occur in the Antarctic Peninsula area. We suspect that there may be on the order of 1000 individuals here, which means they take a lot of food off the table!
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Robert L. Pitman
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service

13th January, 2012. Antarctic Peninsula.
Citizen science.
Today was a quiet day for whale sightings, but was eventful nonetheless. This morning the National Geographic Explorer dropped anchor by the US Antarctic Program's Palmer Station. The guests toured the station and visited a nearby penguin colony, and we went ashore to visit Bill Fraser, who is famous for his long-term studies of Adelie Penguins and the influence of climate change on their populations. In the afternoon we cruised in near white-out snow conditions before landing at another penguin hot-spot; Bob and I alternated keeping watch from the observation deck and worked on data analysis. The highlight was finding a photo-identification match of the Type B killer whale group we tagged in the Weddell Sea on January 10th: they were previously photographed by a tour ship in 2010, some 400km (250 miles) to the south of the tagging site, near to our current location on the west side of the peninsula. With over 90 contributors (and growing) to our database of more than 40,000 photo-identifications, we are starting to fill gaps in our understanding of the distribution, movements and abundance of killer whales in this region. Citizen science in action!
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John W. Durban
Protected Resources Division
Southwest Fisheries Science Center
National Marine Fisheries Service
National Oceanic and Atmospheric Administration 

12 January, 2012

Today we were served the Antarctica weather buffett – blue skies, 30 kts of wind and 12’ seas in the morning, and flat calm seas and heavy snow after lunch. We traversed south, down the west side of the Antarctic Peninsula, through the Bransfield Strait and into the Gerlache Strait. Killer whales are common enough in the Gerlache that we named a local variant that we find there the ‘Gerlache killer whale’ – a small, type B killer whale. The only thing we have seen them eating is penguins, but we have identified at least several hundred individuals regularly using the Geralche Strait and there just are not enough penguins here to satisfy their energetic requirements. Clearly there is more on their menu than we know about. We didn’t see any killer whales today, but humpback whales were common  and numerous Antarctic minke (say ‘minky’) whales were darting about. We hope to put satellite tags on a couple of minkes this trip because almost nothing is known about their migratory movements. They are assumed to migrate to Antarctica during the southern summer to feed krill blooms, and then move north into tropical latitudes during the winter to breed. But we know they are common in Antarctic waters during the winter time and it is clear that the old paradigm requires some tweaking or even overhauling. Our prescription for them is: Take one satellite tag and call us in the morning - for the next 5 months and we’ll sort it out.