One of the things we love most about expedition cruising in Antarctica is helping travellers take part in citizen science projects where they can contribute to active research projects. One of the projects closest to our hearts is Happywhale, which allows travellers to log sightings of humpbacks and other whales to create a global database that whale biologists can use, as well as being used increased protection for whales from vessels in Antarctic waters.
At Swoop, logging all our humpback whale sightings on Happywhale is an essential part of any Antarctic trip – and we always wonder just where those whales go and what they’re doing when they’re not showing us their flukes. To our excitement, we recently received a notification that one of the whales that we had photographed had been seen again – and was already on the radar of a team of biologists who – with the help of citizen science – are researching the humpback whale population in the region. To find out more, we spoke to Professor Ari Friedlaender of the Friedlaender Bio-Telemetry & Behavioral Ecology Lab (BTBEL).
Why whales?
Professor Friedlaender has been working with marine mammals for over 30 years since he was an undergraduate at the Duke Marine Lab, and has been working in the Antarctic since 1997.
‘I love working in a completely wild place that feels really untouched by human hands, with animals that are not influenced by humans and that are living their wildest lives, where nature is in full command,’ he told me.
When Friedlaender started out, it was less than a decade since the end of commercial whaling. ‘Much of what we knew about [whale] anatomy, morphology, reproductive biology, and physiology was from examination of carcasses during industrial whaling,’ he said. Humpbacks were the first species to be hunted in the Southern Ocean from the whaling stations in South Georgia – and the first to see their populations crash as a result. Very little was understood about whales at the time, and the scientists who were stationed in places like Grytviken, did their research to better understand how they could be commercially exploited.
Today, the focus of the BTBEL researchers is rather different. Humpback whales in the Antarctic are believed to have largely recovered their numbers from the devastation of the whaling years, but they face a different set of challenges from the warming Southern Ocean that makes understanding their ecology even more crucial.
Palmer Station
The humpback whale that we had photographed for Happywhale had been recorded by BTBEL by researchers working at Palmer Station, a US research base off the southern tip of Anvers Island in the Western Antarctic Peninsula, and an area regularly visited by expedition cruise ships. The base has been running a long-term ecological research project for several decades now.
‘[Our research is] fundamentally about understanding the structure and function of the marine ecosystem and how it is affected by environmental change,’ Friedlaender explained. ‘Whales are a critical part of this study because they are a key component to the marine ecosystem.’ The large-scale removal of whales from the Southern Ocean during the decades of industrial whaling had profound effects on that ecosystem. Whales play a crucial role in cycling nutrients through the polar waters. This particularly affects krill, the tiny shrimp-like crustaceans at the centre of Antarctica’s ecosystem that are an increasing target for commercial fishing.
Understanding the relationship between whales and krill is at the heart of much of what BTBEL is doing at Palmer Station. While Happywhale plays a role in mapping whale distribution and abundance, the team studies behaviour, body condition, pregnancy rates and a suite of physiological health parameters. This helps to build a more complete understanding of humpbacks along the Antarctic Peninsula, and how the picture varies throughout the season, with changes in sea ice and krill availability.
Modern research techniques
The list of tools and technologies available to BTBEL’s researchers are thankfully a long way from those of the whaling scientists of the 20th century. Friedlaender runs through an almost dizzying list, from long-term satellite transmitting tags that follow migration routes and feeding patterns across the season, to passive acoustic recorders that determine the behaviour of whales throughout the austral summer, and collecting biopsy samples that reveal more about each individual whale.
Some of the techniques involve getting closer to a humpback than would be permitted on a zodiac trip from an expedition cruise ship. For example, multi-sensor suction cups, that can collect an array of information, have to be deployed by hand using a 6-meter carbon fibre pole.
‘We approach the animal slowly and slap the tag on its back,’ Friedlaender explained. ‘The whales usually don’t even respond to the event, and if they do it’s generally a brief startle response and the animals go back to their pre-tagging behaviour very quickly.’ The tags act as a sort of a Fitbit for the whale, recording the most intimate details of their movements hundreds of times a second, from their pitch and roll to their acceleration and the depth of their dives. ‘They also collect video so we can contextualize the movement patterns we notice in relation to what is directly in front of the whale,’ he added, which makes them ideal tools to record a whale feeding on a krill swarm.
After 48 hours of recording the data, the suction cups naturally detach themselves from the animal, and their GPS and VHF beacons allow them to be recovered for analysis.
How to biopsy a whale
Friedlander’s team also takes biopsy samples from their whales. This involves probably the most unusual tool in their arsenal: a crossbow that has a customized bolt with a small tip, like the cap of a ball-point pen. ‘The dart is shot, hits the whale and bounces off, collecting a small sample of 1-2 grammes,’ he said. ‘The dart floats at the surface and we collect it and store the sample. The process doesn’t harm the whales and like tagging, if they respond it is often a startle response that is very brief.’
Even tiny samples like this can reveal encyclopaedias of data about a whale. As well as allowing individual animals to be genetically identified (one reason we know Swoop’s humpback from Happywhale was a female) it can record stress and nutritional hormone levels, toxicology, dietary information, pregnancy status and the size and make up of the breeding population.
Humpback secrets
Using these techniques and more, the BTBEL team at Palmer Station has been able to build up a fascinating picture of how the humpbacks of the Antarctic Peninsula behave.
In the early summer, after completing their migration south from warmer waters, humpbacks congregate on the edge of the Antarctic continental shelf. Due to lower concentrations of krill this early in the season, they have to dive deeply to feed, and eat almost 24 hours a day. In autumn, super-aggregations of krill closer to shore bring the whales into the Peninsula’s shallow bays and fjords – the places that are best for whale sightings. The krill at this time of year contain a higher percentage of fat and make particularly energy-rich meals. This means that the whales don’t need to spend as much time feeding. This is possibly one reason why humpback encounters late in the visitor season can be so enthralling. Freed from the need to eat constantly, the whales are relaxed enough to doze quietly at the surface (a behaviour known as logging), or even curious enough to approach responsibly-behaved zodiacs and kayaking tourists.
Researchers have also been unpacking the mechanics of how humpbacks feed, lunging with their mouths wide open to take big gulps of krill. While this method is undeniably dramatic, it’s also incredibly efficient: a 30-tonne whale feeding in this way uses the equivalent energy of a person climbing three steps. Antarctic humpbacks only feed in the Southern Ocean, and have to fit all their meals for the year into just three or four months, so it clearly pays to eat as efficiently as possible. In that short period, they’ll typically eat up to seven times their body mass in krill.
Discoveries
‘Happywhale has been a really excellent tool to better understand the connections between the whales we work with around the Antarctic Peninsula and their different breeding areas,’ Friedlaender told me. ‘Understanding where certain populations tend to feed can be really valuable to understanding if, or how, certain populations will be differentially affected by things like climate change or krill fishing.’
Since the project began, the BTBEL team has recorded over 1,500 individual humpback whales in their research area. This accounts for around one in eight of the estimated 11,700 humpbacks thought to be found along the Western Antarctic Peninsula. If you’ve photographed a humpback and submitted it to Happywhale, there’s a good chance that BTBEL may have already logged it, and used that sighting to add to the patchwork of data that is unlocking the secrets of these majestic creatures to better understand their role in the ecosystem and the manmade challenges they face.
So the next time you’re in Antarctica and see flukes, have your camera ready. But leave the crossbow work to the scientists.
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