Dear colleague, We are glad to announce the launch of the 2nd edition of the BioDCASE challenge<https://biodcase.github.io/challenge2026/>, where our task 2<https://biodcase.github.io/challenge2026/task2>, focused on the detection of large baleen whales from Antarctica based on Passive Acoustic Monitoring, is back! For this second edition, we have deliberately kept it very close to the first one - so former participants can easily resubmit improved versions of their models, those who ran out of time get a real second chance, and newcomers jump in with a solid, ready-made benchmark from day one! Please note that the challenge has already commenced; submissions will be accepted until June 15. More globally, if you are interested in this kind of collaborative research initiative but you don’t have time to participate this time, please don’t hesitate to contact us to see how you could be involved in this project in the near future! All the best, Dorian Cazau on behalf of the Organization team of BioDCASE 2026 - Task 2 Dorian CAZAU Associate professor in Ocean data science * ENSTA<https://www.ensta-bretagne.fr/fr> * OSmOSE<https://osmose.ifremer.fr/> * Lab-STICC, UMR CNRS 6285<https://labsticc.fr/en/departments/ia-ocean> * Institut Polytechnique de Paris<https://www.ip-paris.fr/>