Real-time monitoring of right whales using autonomous underwater vehicles

Transcription

1 Real-time monitoring of right whales using autonomous underwater vehicles Dr. Kimberley Davies 1, Dr. Mark Baumgartner 2, Delphine Durette Morin 1, Hansen Johnson 1,2, Dr. Christopher Taggart 1 1. Department of Oceanography, Dalhousie University, Halifax 2. Woods Hole Oceanographic Institution, Woods Hole, USA

2 Right whale population status Population size 450 and declining; only 100 breeding females Adults die almost exclusively from ship strike and fishing gear entanglement Natural life expectancy is ~ 70 years but typically they are killed between 20 and 30 Females more likely to die than males (diverging sex ratio) At current rate of mortality, all females will be dead in 20 years Over 80 % of the species have scars from entanglement, many have scars from multiple entanglements Mitigating ship strike & fishing gear risk across the migratory range is mandatory for this species to avoid extinction In 2017 at least 17 animals were killed; 12 in Gulf of St. Lawrence

3 Right whale distribution Endangered right whales Are present year-round in Canadian waters (June- Nov peak), feeding on copepods Acoustic detections of North Atlantic right whales (Genn Davis et al Nature) Recent habitat shift to unknown areas 1.5 mm

4 Motivation Tagging - risky Right whale monitoring Occupy wide range of spatial/temporal scales Challenging to track persistently across migratory ambit Passive acoustics for long term, wide range population monitoring Track by their sounds Visual surveillance short-term, expensive

5 Motivation Moored buoy Autonomous platforms Cover wide range of spatial/temporal scales Oceanographic sensors Built-in real-time communications Quiet for archival/real-time passive acoustics Endurance: > 1 year Endurance: weeks - months APEX profiling float Ocean glider Wave glider

6 Project Goals Real-time remote monitoring of right whales from gliders Define right whale critical habitat Model shipping & fishing gear risk in habitats Build automated real-time data dissemination pathways

7 Enabling Technology Digital Acoustic Monitoring Device (DMON) DMON: A low power hydrophone for autonomous platforms Developed at WHOI by Mark Johnson, Tom Hurst, and Alex Shorter DMON Low-frequency detection and classification system (LFDCS) Fin whale 20-Hz pulses Sei whale downsweeps Baumgartner, M.F. and S.E. Mussoline A generalized baleen whale call detection and classification system. Journal of the Acoustical Society of America 129:

8 Real-time monitoring Operation Transmit to shore: Sensor Data Whale Detections / Spectrogram data DMON/LFDCS status Platform location Platform status Iridium satellite Shore-side server Profiling float Slocum glider Moored buoy Wave glider

9 Detections Large-scale real-time monitoring across the NW Atlantic Slocum gliders Right whale detection Years Effort (days) 1021 Right Whale Detections Moored Buoys 400+ Years Moored buoy Slocum glider All glider deployments also have environmental data Effort (days) 1536 Right Whale Detections 500+ Platform Jan Apr Jul Oct

10 Discovery of Gulf critical habitat persistent occurrence Preference for channels Strong overlap with snow crab fishery Percé Miscou Is. Magdalen Is. Collaborators: A. Vanderlaan, H. Moors-Murphy (DFO), M. Brown (CWI), Phillip Hamilton, Amy Knowlton (NEAq), Tim Cole (NOAA), Jack Lawson (DFO), NOAA, DFO and TC aerial surveillance teams Jul Aug Sep

11 Collaborators: Moira Brown (CWI), Canadian Coast Guard Studies in the Roseway Basin Area to be Avoided: Barrington, Nova Scotia Right whales are frequently present in and around the Roseway Basin ATBA Monitoring & compliance remain critical Jul Sep Nov Initiate visual survey if whales acoustically present

12 Real-time data dissemination Robots4Whales.whoi.edu DFO: expansion in message Whale Alert app apps.cwf-fcf.org/whales Tweet

13 Ship Strike Mitigation Goal: Raise vessel awareness to whale presence WHALE ALERT Automated AIS or NATVEX Messaging System Working with US colleagues east and west coast to think big about how we can generalize these systems

14 Future (2018 and beyond) Glider fleet in the southern Gulf of St. Lawrence 2018 Focus on providing real-time data to partners/stakeholders Science to inform planning activities in high use areas Operational AIS-Whale Alert

15 OTN Glider Technicians: Adam Comeau, Richard Davis, Sue L Orsa, Jude van der Meer Collaborators: Tim Cole (NOAA NEFSC), Angelia Vanderlaan (DFO), Hilary Moors-Murphy (DFO), Moira Brown (CWI), Jack Lawson (DFO), DFO NOAA and TC aerial surveillance teams, crew of the R/V Shelagh, crews of Canadian Coast Guard MSPV Peddle and Cap Breton

16 Funders WHOI program Dalhousie program And many other supporting agencies

17 How well does it work?

18 How well does it work? Evaluation datasets Moored buoy Noman s Land Island March March 2016 Woods Hole Slocum glider Great South Channel April - July 2015 April July 2016 Woods Hole

19 How well does it work? Near real-time analysis of pitch tracks Right whale C o m p a r e Audio analysis of archived recordings

20 How well does it work? Number of days Missed occurrence False occurrence Accuracy Slocum glider Slocum glider Moored buoy Evaluation of near real-time estimates of daily whale occurrence Truth = analysis of recorded audio

21 How well does it work? Number of days Missed occurrence False occurrence Accuracy Slocum glider Slocum glider Moored buoy Evaluation of near real-time estimates of daily whale occurrence Truth = analysis of recorded audio

22 How well does it work? Number of days Missed occurrence False occurrence Accuracy Slocum glider Slocum glider Moored buoy Evaluation of near real-time estimates of daily whale occurrence Truth = analysis of recorded audio

23 How well does it work? Number of days Missed occurrence False occurrence Accuracy Slocum glider Slocum glider Moored buoy Most missed calls occur during non-monitored periods missed occurrence can be improved by increasing transmitted data