Day 3 of the 22nd Biennial Conference on the Biology of Marine Mammals. Some of the faces amongst the thousands of participants are starting to become familiar. Topics that were completely unknown to us are gradually becoming more comprehensible. But our heads are still spinning with all these presentations and new posters to discover and process. From one room to the next, the lectures alternate on diverse themes ranging from fin whale pharynx morphology to the mapping of threats to marine mammals. Here are a few highlights of the day.
The dusky dolphins of New Zealand are (highly) gregarious. They form groups of hundreds of individuals, making them difficult to study individually. Heidi C. Pearson’s team fitted some of these dolphins with tiny cameras mounted on tags placed on their backs to record diving depth and swimming speed. In this manner, underwater maternal behaviours can be studied. During this biennial, the technique of placing cameras on marine mammals was also discussed for gray whales in California and elephant seals in Japan.
For research conducted in waters far from harbour and limit costs, the “saildrone” was invented in 2015. Resembling a remote-controlled sailboat, this device is plying the waters of the Bering Sea. Underneath, a hydrophone is used to conduct passive acoustic monitoring. Since it was first designed, the saildrone has been modified to be less noisy and therefore better able to detect the communication of different species. A technology worth keeping an eye on.
The use of aerial drones is increasingly popular for studying cetaceans. We know that we can collect breath or hormone samples or study behaviour. But, as described by Sharon Nieukirk, they can also be used to create a body mass index for gray whales! The model created by the team could be useful for other baleen whales and might enable better monitoring of the health status of an individual or even a population.
But the biggest buzz is the research of Dara Orbach on marine mammal genitals. To better understand the joint evolution of penises and vaginas in bottlenose dolphins, harbour porpoises and harbour seals, this researcher made silicone casts of the female reproductive tract and inflated penises to study how they penetrate the vagina during simulated copulation. The results provide a better understanding of reproduction in animals in a medium which one might describe as challenging during intercourse for animals without any arms! We should also point out the humour the speaker added to her presentation.
North Atlantic right whales
At dinner hour there was a conference entitled “Life on the Edge: Status and Conservation Concerns for the North Atlantic Right Whale”. Scott Krauss of the Anderson Cabot Center for Ocean Life, Amy Knowlton of the New England Aquarium, Peter Corkeron of the National Oceanic and Atmospheric Agency (NOAA), Mark Baumgartner of the North Atlantic Right Whale Consortium and Tonya Wimmer of the Marine Animal Response Society discussed the future of this endangered species. Breeding females, the population’s future, are growing scarcer (they are estimated to number about one hundred) and bycatch is an increasingly significant threat. Conservation efforts will have to go beyond borders: “Whales don’t care where they are, we have to act internationally,” Krauss said with verve. The four solutions proposed seem straightforward: reducing vessel speeds in certain areas, rerouting shipping lanes to less critical areas for whales, modifying fishing gear to be less dangerous to whales, or even altering such gear to make it rope-free.
Just two days to go, yet hundreds of presentations and posters remain. We would love to offer a comprehensive summary and share each and every discovery, but most importantly, once the dust has settled, we will start to develop new projects to pursue.
For a journey through the conference abstracts, consult the scientific program here.
To read the previous day summary: