When I was in middle school I wrote a report about bubble rings but I don’t remember if I had the same problem I do now of trying to sound serious, I was probably less concerned about that at the time. That paper was about individual ring-shaped bubbles, like the kind dolphins (or humans like me) blow underwater. This blog is about the bubble nets that humpback whales create to corral their prey underwater (I have yet to master this skill).
I have just finished auditing about 7.5 hours of video footage that we obtained from the suction cup tag we deployed on a Humpback whale earlier this month. My objective was to create a detailed log of underwater foraging behavior. We were especially interested in recording video footage and collecting fine-scale movement data from the whale during coordinated bubble net feeding events. This video footage is the first of its kind documenting this type of feeding behavior in Antarctic Humpback whales.
I found many occurrences of both bubble net and lunge feeding events, and in some cases the underwater visibility was good enough to observe other whales in the video frames. Throughout most of the 7.5 hours the tagged whale was travelling and foraging with at least one other whale, but at one point up to three other individuals were present. Other notable behavior included vocalizations and pectoral fin slapping on the surface of the water. Krill were frequently observed rushing by the forward facing camera just after lunge events.
Watching these videos over the course of a few days I became kind of committed to this whale’s story, and where each video ended and another began I found a narration running through my head that went something like, “next time on the life of the whale… will he find more food?” When the final video ended I even felt a little sad that I wouldn’t be able to keep following him on his journey.
I’ve included some screen shots below to give you a better idea of what I observed while watching the videos.
P.S. I named this whale Mr. Opihi man, since the barnacles and the suction cups stuck to his back reminded me of the way Opihi (the Hawaiian word for limpet) stick to the rocks.
We had an eventful weekend on the LMG, visiting a British research station on Adelaide Island on Saturday and nearby Avian Island on Sunday. We arrived at Rothera Station early Saturday morning and traded most of our LTER team for a group of British scientists. The British base was very welcoming and had a full of day of crevassing, skiing, hiking and boating activities planned for us. Meanwhile, their scientists took advantage of the use of our ship for a few offshore science projects.
We “whalers” took advantage of the free time and good weather and spent the morning looking for Minke, Humpback and killer whales in the vicinity of Rothera. We had hoped to put a stop to our long streak of days without whales but unfortunately there were no whales to be seen. Despite this, we had a great morning taking photos of the many icebergs, leopard seals, Wilson’s storm petrels and blue-eyed shags in the area.
Sunday was a beautiful bluebird day and we had a gorgeous transit from Rothera around the south end of Adelaide Island to Avian Island. We left two of our LTER colleagues on Avian and they will be camping there for the week. They will be studying the island’s population of Adelie penguins, conducting diet studies and assessing reproductive success by weighing, measuring and counting Adelie chicks.
Spending a week each year on Avian Island is an important aspect the seabird component of the LTER program because Avian Island serves as a sort of “control” study site, to compare to the more rapidly changing Palmer site. The differing physical and biological conditions at each of these two sites allow scientists to assess how things like local sea-ice conditions and biological productivity affect each of the local penguin populations. There are around 80,000 Adelie penguins on Avian, so you can imagine that we could smell the krill-colored guano long before we landed on the island.
I’ve just finished uploading some great photos of the past week on the ship, here.
You’ll notice this is the same blog post from yesterday on a different website. You can find photos at the end of the most recent post. I encourage you to read more of the blogs on that site, which is the blog site for the Geospatial Ecology of Marine Megafauna lab at Oregon State University.
Yesterday someone said to me, “I don’t know if it was sunrise or sunset, but it was beautiful” So it goes on the LMG, the surrounding scenery is incredible but the general work schedule on this research ship makes it difficult to remember what time of day it is.
Here on the Antarctic Peninsula, the sun never really sets and our daily schedules are dependent on things like the diel vertical migration of krill, the current wind speed and the amount of sea ice in between us and our study species, the humpback whale. For these reasons, we sometimes find ourselves starting our workday at odd hours, like 11:45 pm (or 4:00 am).
We are about one week into our journey and so far, so good! We have spent the last four days transiting between various sampling stations around Palmer deep, which is an underwater canyon just south of our home base at Palmer station. When conditions allowed, we loaded up our tagging and biopsy gear into a small boat and went to look for humpback whales. We’ve been incredibly successful with the limited amount of time we’ve had on the water and this morning we finished deploying our sixth tag.
We brought a few different types of satellite tags with us to deploy on humpback whales. One type is an implantable satellite tag that transmits location data over a long period of time. These data allow us to gain a better understanding of the large-scale movement and distribution patterns of these animals. The other tag we deploy is a suction cup tag, named for the four small suction cups that attach the tag to the whale. These multi-sensor tags measure location as well as fine scale underwater movement (e.g. pitch, roll, and heading). They are also equipped with forward and backward facing cameras and most importantly, radio transmitters! This allows us to recover the tags once they fall off the animal and float to the surface (after about 24 hours). The data we get from these tags will allow us to quantify fine-scale foraging behavior in terms of underwater maneuverability, prey type and the frequency, depth and time of day that feeding occurs.
When we deployed each of these tags we also obtained a biopsy sample and fluke photos. Fluke photos and biopsy samples allow us to distinguish between individual animals, and the biopsy samples will also be used to study the demographics of this population through genetic analysis.
Now that we’ve deployed all of our satellite tags and have recovered the suction cup tag just in the nick of time (!), we are starting our first major transect line toward the continental shelf. We will be continuing south along these grid lines for the next week.
Right now we don’t have a good enough internet connection on the ship to post photos, but I’m hoping to get around that and have a few up for you soon!
Well we are now on Day three of the ship. Unfortunately the rocking of the vessel does not help me sleep. But I guess the more I am awake the more time I can spend on the bridge looking for animals.
We crossed the 60th parallel (60 deg. South) at about 10:35 this morning. It is currently 3:23 pm and a huge bout of fog has come in and surrounded us, making whale sightings a bit more challenging. Just prior to crossing the 60th parallel, we crossed over into the southern ocean. In doing so the temperature dropped from about 4°C to about 1°C. It even snowed this morning.
We spotted our first whale at about 8:30 am. Passed by a bunch of fin whales. They are easy to spot at distance as their blow towers over the rest of the water in a cloud of mist. They have a smaller dorsal generally as compared to the sei whales we seen coming through the straits of Magellan and are an olive/brown color. Have made several sightings of these guys through out the course of the day, of which one individual decided to roll and show the bottom of his/her left fluke blade.
We have also started to see some different bird species as well, my favorite of which is the cape petrel. Their lacey, checkerboard black and white patters are just stunning. We have also seen some giant petrels, Wilson’s storm petrels, grey-headed albatross and now some light-mantled sooty albatross.
At about 7:30 I noticed some spray coming across the water, the winds were not so bad so I assumed there were some whales near by. Not long after a giant dorsal fin emerged about 20 ft starboard of the vessel. It was a group of three killer whales, of which one was a male (have large dorsal fins). They did not stay for long. Once they got closer they appeared to take a deep dive and disappear.
We are travelling first to a station at Cape Shirreff to drop off a scientist and pick up their garbage. From there we will proceed to Palmer Station (another 20 hours or 200 miles) traversing through the Gerlache Strait. We should finally arrive at Palmer station sometime the afternoon of the 8th. Hopefully we can be up and running in about a day.
Here is the current weather in the Drake Passage: Swells about 4-6 ft. high, we are in roughly 4000 m of water. The wind is travelling on average of 15 knots and the wind chill is -11.8° C. The water temperature is now 1.07° C.
The R/V Lawrence M. Gould departed Punta Arenas, Chile yesterday, marking the beginning of the annual Palmer LTER research cruise. Myself (Erin Pickett) and my lab mate Logan Pallin, are looking forward to sharing our adventures and research with you over the next three and a half months! Logan and I are graduate students at Oregon State University’s Marine Mammal Institute. While on the cruise and at Palmer Station, Logan and I will be working with our graduate advisor, Dr. Ari Friedlaender, and with Dr. Doug Nowacek from Duke University. Ari and Doug are two of the Principal Investigators leading the cetacean component of the Palmer LTER project.
The work that we will be doing over the next few months is part of a long term ecological research (LTER) program based out of Palmer Station, Anvers Island, along the Western Antarctic Peninsula. Over the next few months our whale team will be conducting cetacean surveys and collecting acoustic-based prey measurements of Antarctic krill. Much of our effort will be focused on humpback whales, and we will be using methods such as photo identification, tagging and biopsy sampling to understand more about this species recent recovery in this area and to learn more about the ecological roles that these large baleen whales play in the marine ecosystem along the peninsula.
We are especially interested in learning more about the foraging ecology of humpback and minke whales, how their behavior is influenced by their primary prey (Antarctic krill), and how their population demographics (genetics, sex, hormones) may change over time. Many of the region’s top predators share this prey resource, which is declining as a result of sea ice loss. A central objective of our research is to understand how climate induced changes in this polar marine environment are affecting these top predators.
Until we reach the northern boundary of our study area where we will begin our official surveys, we will be occupying ourselves on the ship with a bit of bird watching. I’ll be teaching Logan how to distinguish a duck from a petrel, and a “freaking huge bird” from a Royal albatross. So far in addition to a couple of royal albatross we’ve spotted white chinned petrels, black-browed albatross, and South American terns. It’s nearly tropical outside this afternoon, breezy and 11.2˚C, and a group of Peale’s dolphins are riding our bow wake, so enough writing for one day!