Marine mammals in the Rusalca region 2009-2012:

Acoustic recordings and visual sightings

Kate Stafford University of Washington

Funding NSF_AON (2012- onwards)WHOI Arctic Program (2 instruments purchased, travel support cruise 2010)NOAA (I instrument purchased, travel support to cruise 2011)Tom Weingartner and Rebecca Woodgate provided space on moorings

Bering Strait

• Migratory pathway for Arctic marine mammals that move between the Bering and Beaufort and Chukchi Seas– Bowhead and beluga whales– Walrus, ice seals

• Used seasonally (summer/fall) by sub-Arctic spp– Fin, Humpback, minke, killer whales, gray whales

Decreased sea ice

• Decrease in habitat for walrus, polar bears, ice seals, bowheads (?)

• Increased habitat for sub-Arctic spp• Increase in shipping and O&G exploration =

increases in ambient noise– Increase in ship strikes of large whales?

Sighting data

Cruises with marine mammal observations • 2009 (1)*• 2010 (1)*• 2011 (1)• 2012 (2)** Surveys in Russian EEZ

All Rusalca sightings 2009-2012

All Rusalca sightings by species

Humpback whale sightings

Fin and minke whale sightings

Killer whale sightings

Papers in preparation• Occurrence of Subarctic Cetaceans in the

Southern Chukchi Sea, 2009-2012– To be submitted to Oceanography ~July 2013– Synthesizes boat-based visual data from Rusalca,

CHAOZ, CSESP; aerial survey-based visual data from ASAMM/COMIDA

• Occurrence of gray whales in the southern Chukchi Sea 2009-2012

Arctic whales

• Do not (usually) occur in study area during summer months – not seen by visual surveys

• Best way to monitor bowhead and beluga whales, bearded and ribbon seals and walrus is Passive Acoustic Monitoring (PAM)

PAM

• Good year-round, all weather, 24 h/day• Can “hear” further than “see”• Different species are readily told apart• In addition to Arctic spp, “late” summer whales

can be detected• Good way to monitor ship passages• To date, only US side of Strait has been

monitored, ideally the western Strait should be instrumented

Citta et al. 2012 Arctic

Citta et al. 2012 Arctic

Instruments first deployed August 2009

Redeployed every year since

Subsample the data (10 min/hour)

We have had issues with battery power so none of the instruments have lasted a full year to date

Species detected

• Bowhead (Nov-Feb, Apr)• Walrus (October – Dec, April-Jun)• Bearded seal (year-round)• Beluga (Oct-Dec, Apr-May)• Ribbon seal (Oct)• Fin whales (Aug-Oct)• Humpback whales (Aug-Nov)• Killer whales (Sep-Oct)

A2W

Humpback whale detections

Humpback and bowhead detections A3

Papers in preparation• Humpback whales sing north of the Arctic Circle

– Acoustic data from Bering and Davis Straits show that humpback whales are singing well into winter near to or north of the Arctic circle

– Submittal July 2013• What sound environments do bowhead whales annually encounter in

the Bering, Chukchi and Beaufort Seas?– SOAR synthesis paper that examines bowhead whale migration

via PAM– Due to editors June 2013

• Acoustic detection of bearded seals (Erignathus barbatus) in the Bering, Chukchi, and Beaufort Seas– Master’s thesis chapter– Planned submittal to Arctic September 2013

Future work

• Go through all data systematically for all species

• Determine ambient noise levels• Continue to occupy A2W and A3

– Instruments will be deployed this year

• Ideally add a hydrophone to A1– Monitor autumn/winter bowhead whale

migration