Deep-sea corals, whales and squids

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view of blue research vessel, seen from just above the sea level

RV Anna Weber-van Bosse from the perspective of a whale (Photo: NIOZ)

This expedition on the RV Anna Weber-van Bosse from 11-22 September combines the 2026 deep-sea pray-hunting whale project of Fleur Visser and the CONDOR seamount project, investigating the deep-sea ecosystems near the Azores. 

 

Saturday 19 September

By Fleur Visser, Chief Scientist (this cruise is part of her NWO-Vidi "Tracing top predator-prey interactions into the deep sea".)

Welcome on board of Anna Weber van Bosse! We are underway for our research cruise off the islands of Terceira and Faial of the Azores, to investigate how (and why?) whales forage in the deep sea, and to explore how we can restore ecosystems on the deep-sea floor. To do so we combine a range of methods, in a team of scientists and crew of a wide range of expertises. The deep sea is a huge ecosystem, and it is difficult to reach and observe. Combining skills and techniques is almost a must, in order to advance. Our team joins deep-sea ecologists, oceanographers, whale and squid biologists, bio-acousticians, deep-sea technicians,  theoretical ecologists, deep-sea benthic ecologists and DNA specialists – plus a highly experienced research vessel crew. We observe and record the deep sea using echo sounders, hydrophones, video transects, environmental DNA- and nutrient sampling. We also deploy moorings for long-term recording of deep-sea predation, and landers to monitor the behaviour and growth of the corals that are returned to the deep-sea floor. If fact, I, as a whale scientist, am currently watching the whale prey I am looking for -deep-sea squid and octopus- during a video transect in a coral restoration site, ran by our oceanography and coral specialists.

Join us for a little while, and, if inspired, perhaps also for our haiku competition

squid is hard to find

we must behave like whales, to

write in sepia

Listening to the Deep: Long-term Cetacean Acoustic Monintoring in the Azores

10-11 September by Jace Fuller, Simone Baumann-Pickering and Bruce Thayre

In the 24 hours before recovery of our mooring off Terceira, we captured a remarkable succession of six cetacean species. Sperm whales dominated the afternoon; beaked whales, false killer whales, and unidentified dolphins filled the small hours. Below, we walk through who we are, what we are working on — and what the ocean told us.

Representing the Marine Bioacoustic Research Collaborative, Scripps Institution of Oceanography at the University of California San Diego, are Dr. Simone Baumann-Pickering, Principal Investigator of the Acoustic Ecology Lab; Bruce Thayre, Marine Technician; and Jace Fuller, a PhD student in the Acoustic Ecology Lab.

Our long-term goal is to monitor the density of cetaceans and their prey off Terceira Island and correlate cetacean diving behavior with prey and oceanographic conditions to learn about predator-prey dynamics and species interactions. On this cruise, we recovered a year-long mooring deployment from which the photos and cetacean acoustic data in this post were sourced. We plan to deploy a similar mooring for another year of data, as well as a small passive acoustic mooring for an additional year of observations, making this our 6th year of recordings.

 

Three people standing on deck of a research vessel holding a large yellow buoy

Simone Baumann-Pickering, Jace Fuller, and Bruce Thayre with the recovered mooring buoy

Our multi-instrument mooring included a continuously sampling High-frequency Acoustic Recording Package (short HARP) to record cetaceans and other environmental sounds, active acoustic fisheries echosounders (Simrad Wideband Autonomous Transceiver, WBAT) to identify backscatter layers throughout the water column and locate prey, and oceanographic sensors (Sea-Bird microCAT) to measure temperature, salinity, and dissolved oxygen at various depths. These instruments allow us to relate the acoustic presence of cetaceans to the physical and biological structure of the water column.

Five people wearing safety helmets securing a yellow buoy onboard a research vessel

The team secures the large yellow surface buoy on deck before processing the instrument package below (Photo: NIOZ)

view from above of five people working on deck of a research vessel

The Simrad Wide-Band Autonomous Transceiver (WBAT) is visible on deck as the team brings it aboard.

Graphic with timeline showing the different species found

Overview of species found on september 10 and 11 (Credit: Marine Bioacoustic Research Collaborative)

Example of recording echolocation clicks of sperm whale and goose-beaked whale (Credit: Marine Bioacoustic Research Collaborative)

Here above you can hear a short fragment of the acoustic layering of two deep-ocean foragers. The sperm whale's lower-frequency echolocation click train anchors the scene below 30 kHz, while the goose-beaked whale's frequency-modulated echolocation pulses cut through the upper register — two species occupying complementary acoustic niches in the deep sea, at the same moment.

The spectrograms are from an autonomous high-frequency acoustic recording package (HARP) deployed in the Azores, 10–11 September 2026. Top panel: long-term spectral average (LTSA), Time average = 5 s, FFT = 1000 points, Sampling rate = 200 kHz. Bottom panel: bandpass-filtered detail clip (2–98 kHz). Colour indicates signal amplitude with warmer colors having higher amplitudes.

In the deep blue sea

we recorded marine life

myst'ries to be solved