Marine Mammal Research at Aarhus University, Ecoscience

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The paper behind our recent research on ship noise and harbour porpoises in Danish waters is now available on the Wiley Online Library.

Read it here:
onlinelibrary.wiley.com/doi/10.1111/...

#MarineEcology #Wildlife #MarineMammalScience #Research #HarbourPorpoise 🌱🧪🌏🌐

Marsvin forstyrres af skib YouTube video by DCE - Nationalt Center for Miljø og Energi AU

Keep up to date with coming news on these projects here: ecos.au.dk/forskningraa... (in Danish)

Provided by Dr Fredrik Christiansen, Senior Researcher PhD, MSc, BSc Marine Mammal Research, Department of Ecoscience Aarhus University

'A mechanistic approach to understanding birth timing, calf growth, and residency of southern right whale mother–calf pairs on their calving ground'

www.sciencedirect.com/science/arti... 🌐🌏🌱🧪

Diagram below for variables and mechanistic model used in the study 🐋

Image by Dr Fredrik Christiansen, Senior Researcher PhD, MSc, BSc Marine Mammal Research, Department of Ecoscience Aarhus University

Our recent study in Ecological Modelling shows that southern right whale mother-calf pairs leave calving grounds once calves reach ~8 m in length, not after a fixed time. Larger, fatter mothers help calves reach departure size faster! 🐋⚡

Read it here:
www.sciencedirect.com/science/arti... 🌐🌏🌱🧪

So great you had a read, you got that right!

Artwork by Zoltan Nemeth (cetek-art.com)
Photo by Nico Lewin 🌏🌐🧪🔊

Influence of water temperature, body size, condition and gull-inflicted lesions on heat loss in southern right whales in Península Valdés, Argentina Summary: Warm calving waters provide limited thermal benefits to southern right whales as body size and condition ensure effective insulation, although gull-inflicted lesions can compromise it in smal...

Our recent study in the Journal of Experimental Biology demonstrates how body size and condition reduce heat loss in southern right whales & that they do not need to migrate to warmer waters to offset heat loss in their newborn calves🐋

#marineecology #Science #marinemammalresearch #Rightwhales 🌐🌏🧪🌱

#offshorewindfarm #emf #scientists #porpoises #semla #research #havforskermøde2026 #offshorewind #marinescience #electromagneticfields #scientificresearch #marinelife #harbourporpoise | Joanna Sarnoci... 🐬 🌊 ⚡ Did you know? When electricity flows through a cable from an #OffshoreWindFarm, it generates an electric field (from the voltage) and a magnetic field (from the current). Together, these are kno...

A new collaborative study explores how EMF from subsea cables may be felt by harbour porpoises 🐬🌊

More details linked in the video 🌐🌏 @au.dk

#offshorewind #marinemammalresearch #Science🧪

Thanks @mattidcarter.bsky.social for the fantastic effort in bringing together data from all over the North Sea. This will bring the distribution and habitat use of harbour and grey seals to a whole new level!🦭

+ our Jonas Teilmann, Anders Galatius, Rune Dietz & Jacob Nabe-Nielson contributed 🧪🌐🌱🌊

2 hydrophones were carried into the Kattegat by storm, presumed lost... Vegar finds one south of Hurum! Sees our labels and gets in touch. Legend. A local rescue mission begins & all instruments were located. Data retrieved! The result was joy all round 🦭🔊🛥️

story:
www.facebook.com/RibRoy/posts...

Last week, our 2 PhD students & colleagues successfully conducted a full turnover of 8 #acousticrecording stations 🎧 out in Aarhus Bay 🌊. The data feeds into a year-round #marinesoundscape monitoring programme to assess #noisedisturbance for #harbourporpoises 🚢🐬(funded by AVJ Naturfond).

Thanks for sharing!!

Rikke Guldborg Hansen presented “Sea-ice habitat association of a small ringed seal population”, co-authored by Aqqalu-Rosing Asvid from Pinngortitaleriffik (The Greenland Institute of Natural Resources). The study presented aerial survey data of abundance and habitat selection from two surveys (2018 and 2025) for the genetically distinct Kangia ringed seal, uniquely adapted to the environment found in the UNESCO-listed Ilulissat Icefjord (Kangia in Greenlandic). Observers, photographer: Emile Holba Seal: Aqqalu-Rosing Asvid

Greenland Science Week Conference https://www.scienceweek.gl/kopi-af-abstract-submission

At Science Week, Greenland 🌏🇬🇱

7 years of aerial survey data reveal abundance and habitat selection of the genetically distinct Kangia ringed seal, uniquely adapted to the UNESCO-listed Ilulissat Icefjord🦭🌱🌐🧬

Rikke presented research, with Aqqalu Rosing-Asvid (Pinngortitaleriffik) @GINR

🔗s in 📷

shop.elsevier.com/books/oceani...

🔊 New volume covering oceanic dolphin species

Ridgway & Harrison’s Handbook of Marine Mammals: An expert-written review & fantastic resource for anyone working with/ fascinated by marine mammals 🌊🐬

Our Anders Galatius has contributed the chapters on white-beaked & Atlantic white-sided dolphins 🧪🌏

Graphical abstract for the paper 'A simple categorization method for frequency notched echolocation.' Here, we describe how from four passive acoustic monitoring stations in Skagerrak, echolocation clicks from white-beaked dolphins were manually audited. These signals exhibit distinct spectral peaks and notches between 20-80 kHz in 75-90% of visually confirmed species recordings. A nonlinear least squares model was used to dynamically map the spectral banding pattern. Our template was significantly correlated with 87% audited white-beaked dolphin events, making this a viable, computationally efficient method.

It's live! Please see my new paper in Ecological Informatics on the #detection and #categorization of frequency notched echolocation from wild recordings. 🐬🔊👇

www.sciencedirect.com/science/arti...

Professor Jonas Tielmann presenting the paths six minke whales took after being tagged in Scandinavia.

First up we have Prof. @jonasteilmann.bsky.social giving an overview of the hight ambitious North Atlantic #minkewhale #tagging project.

Live from the Danish Marine Mammal Symposium! Here I'll be posting talks given by @marinemammalsau.bsky.social scientists! Stay tuned 🐋🐬🦭🌊🚢🔊

Keynote speaker Fredrik Christiansen presented impressive work on drones for non-invasive monitoring and calculating bioenergetics of whales around the globe 🐋🌍 🌱

Mia Kronborg, also from Marine Mammal Research @au.dk presented upcoming open-source database for harmonising C-POD data, VALKYRIE 🐬 🌐 🧪

This week, Sweden had their first marine mammal research symposium, hosted by Johanne Stedt at #LundUniveristy

This brought discussion for further scientific meetings, presentations of new #MarineMammalResearch and collaborations between the Scandinavian countries.

🐋🌍 🌱🐬 🌐 🧪

'Crew on Skoven 2 hauling in scientific equipment after months at sea' Static acoustic recorders (anchored to the seabed) listen for porpoise echolocation clicks. Very short, high-frequency sounds (around 130 kHz) the animals use for navigation and hunting.

'Line Khyn from NIRAS and Poul Boel Jørgensen from Aarhus University, Department of Ecoscience' Project is shared equally by Aarhus University & NIRAS. Together with partners across the Baltic: This is a large, international project (involving Denmark, Sweden, Poland, Germany, and others) focused on monitoring the critically endangered Baltic Proper harbour porpoise population. It is funded by the Aage V. Jensen Charity Foundation and the Danish Env. protection agency.

'Poul and Line holding CTD' CTD (Conductivity, Temperature, Depth) casts are often made alongside acoustic deployments so researchers can link porpoise presence with environmental conditions.

'Skoven 2 cruising the Baltic sea'

AU and NIRAS are monitoring the critically endangered Baltic harbour porpoise through the international project SAMBAH II 🌐🐬

Since last week, all equipment deployed in summer 2024 to log echolocation clicks from porpoises has been safely retrieved!

📷 captions for more details
sambah.org 🧪

www.int-res.com/abstracts/me...

By being large and fat, baleen whales can endure long periods with little or no prey 🌐🌏🧪🌱

We found that:
🐋 A southern right whale in average condition could survive up to 17 months without feeding.
🐋 But a severely entangled North Atlantic right whale may only last about 50 days.

🔗 to paper:

📸 Southern right whale: Fredrik Christiansen, Aarhus University 📸 North Atlantic right whale: Center for Coastal Studies, taken under NOAA permit #24359 👉 Link to paper: https://www.int-res.com/abstracts/meps/v768/meps14914

Our recent study in the #MarineEcologyProgressSeries
highlights how body size, condition, and human impacts shape the survival of right whales & why they are so vulnerable to prey limitation and disturbance 🐋

🔗 in thread

#Conservation #WhaleResearch #RightWhales #OceanHealth #MarineScience 🌐🌏🧪🌱

Polar bears are being poisoned by mercury dumped a century ago | BBC Science Focus Magazine Toxic tides are delivering the dangerous pollutant to animals and people at the top of the world

Here is the story covered by BBC w/ free access 🌏
@bbcscience.bsky.social

🌐🐋🐻‍❄️🧪

Study Shows Mercury Levels in Arctic Wildlife Could Rise for Centuries

New York Times article discusses @nature.com paper by our Rune Dietz, Christian Sonne, and others at @au.dk and the University of Copenhagen 🌐🐋🧪🌏

@newyorktimeshaiku.bsky.social @ucph.bsky.social
#Science #Research #impact #Mercury #Arcticchange

Rikke Guldborg Hansen is a senior advisor working from the marine mammal research team at AU. She is working on this project in collaboration with RUC and the Greenland Institute of Natural Resources. Rikke has a focus on Arctic marine mammals and the effects of anthropogenic and climatic changes. She is leading monitoring programmes and bridging gaps between scientific and local knowledge with respectful communication and public outreach. At AU she is advising for marine mammals in Danish waters. This includes work with Novana and the different advisory groups for marine mammals under Helcom, Ospar and Ices. 

Photo taken by Rikke in Maniitsoq, August 2025

Our Rikke on fieldwork in Maniitsoq, Greenland 🇬🇱
Collecting samples to study #genetics, #feedingecology, #reproduction, and the presence of pharmaceuticals & other
#persistentchemicals in harbour porpoises.

See photo captions and link for project details 🐬🌐

veluxfonden.dk/en/projekt/p... 🌱🌏

Society for Marine Mammalogy The mission of the international Society for Marine Mammalogy is to promote the global advancement of marine mammal science and contribute to its relevance and impact in education, conservation and ma...

Changes made by our *researchers are now recommended by The Taxonomy Committee of the Society for Marine Mammalogy.

*Anders Galatius, Morten Tange Olsen & Jakob Tougaard @au.dk , in collaboration with researchers from the Smithsonian Institution and University of Copenhagen.

🌐🌏🐋🌱🧪

Phylogenomic, morphological and acoustic data support a revised taxonomy of the lissodelphinine dolphin subfamily The dolphin genus Lagenorhynchus has included six species of dolphins characterized by short, wide rostra. Genetic analyses have consistently found th…

We have redefined Dolphin Taxonomy 🐬

5 former Lagenorhynchus species have been reassigned to the new/revived and redefined genera:

Aethalodelphis, Leucopleurus & Cephalorhynchus

#marinemammalresearch #globalecology #marineecology
#cetaceans #research #genetics #science 🐋🌱🧪🌐🌏

Watch a short clip of the retrieval of a DST tag from the sea at Fanø