PRISMM – survey to estimate distribution and abundance of marine megafauna off British Columbia

By The Marine Detective on August 14, 2018

[Update on the Marine Mammal Provisions Rule: Article by CBC on 2021-12-01: See this link re. “In 2023, all seafood entering U.S. will have to show it was harvested with American-style protections.”]

PRISMM = the Pacific Region International Survey of Marine Megafauna.

Yes, I now have a t-shirt with “marine megafauna” on it which I consider a measure of a very happy and fortunate life. I was a spotter on PRISMM for two weeks. Colleagues were aboard for up to six consecutive weeks.

The survey, led by Fisheries and Oceans Canada’s Cetacean Research Program, is aimed at determining the distribution and abundance of marine mammal’s in Canadian Pacific Waters. It involves ten weeks of surveying and two research vessels (two weeks overlapping between the two vessels).

Vessel #1. Now complete: Six weeks (July 3rd to August 13th) were surveyed from the CCGS John P.Tully (69 m), covering more than 6,000 km of BC’s offshore waters. In addition to a visual survey effort, an acoustic array was towed 24 hours a day to allow for the detection of deep diving cetaceans such as Sperm Whales and species of beaked whales and to provide detection of additional species when sighting conditions were poor.

Vessel 2. Ongoing: Four weeks (August 6th to September 6th) are being surveyed from the CCGS Tanu (51m long). These weeks will focus on BC’s coastal waters.

The maps below show the area covered by the Tully – from the west coast of Vancouver Island and Haida Gwaii to 200-nautical-miles (370 km) offshore (to the edge of Canada’s exclusive economic zone). The Tanu is covering the waters on the inside of Haida Gwaii and Vancouver Island.

Detail about the PRISMM Survey from Fisheries and Oceans Canada’s website.
“Surveys of this magnitude have been conducted before by DFO in Atlantic Canada and the Central Arctic, but not in Canadian Pacific waters . . . The objective is to obtain data for as many cetacean species (e.g. whales, dolphins, and porpoises) as possible, as well as other marine species (seals and sea lions, sharks, sea turtles). [Hence “marine megafauna” as not all species are marine mammals.] Important research identified for these species include the assessment of population status, abundance trends and seasonal distribution. The emphasis will be on estimating abundance of marine mammal populations, which requires systematic surveys of all waters off British Columbia. However, this survey also provides a chance to refine our knowledge of the critical habitat of species listed under Canada’s Species at Risk Act (SARA), and for observation of species not listed under SARA, on which there has been less research effort in the past.”

This is not the first line transect survey conducted by the Cetacean Research Program off British Columbia’s coast. For many years, surveys have been conducted for two weeks in spring and two weeks in summer. It is also important to acknowledge that the Raincoast Conservation Foundation conducted surveys of coastal BC waters (the area being covered by Tanu during PRISMM) in 2004, 2005, 2007 and 2008 publishing much-valued abundance estimates for Harbour and Dall’s Porpoises, Pacific White-Sided Dolphins, Humpback, Minke and Fin Whales and contributing to the knowledge of line transect survey methodology.

The catalyst for the more extensive and systematic PRISMM line transect survey is an American regulation, the Marine Mammal Import Provisions Rule, that went into effect on January 1st, 2017 (with a 5-year grace period). To comply with this regulation by January 1st, 2022, countries importing seafood into the United States must be able to prove their fisheries monitor and limit marine mammal bycatch with the same standards as U.S. fisheries are required to do under the Marine Mammal Protection Act. Reportedly, such extensive surveys will be conducted every eight years (Source: Vancouver Sun).

In order to allow for the best possible abundance and distribution estimates, it is necessary to adhere to the line transects, consistent speed, and further protocols.Thereby, PRISMM did not involve some of the research objectives of past surveys where a smaller vessel is launched to achieve DNA sampling, identification of individual whales, and prey sampling.

In addition to the survey effort, moored acoustic recorders were retrieved and deployed during PRISMM. These Autonomous Multichannel Acoustic Recorders (AMARs) are moored deep below the surface (up to ~2,400m) to passively monitor for cetacean vocals (they do not send out any sound). They need to be retrieved to get the recorded data, allowing for acoustic detection of cetaceans, and to have their batteries replaced so they can be repositioned. The retrieval of AMARs is a thing of wonder.  The recorder with its buoy is released from the mooring when it receives a signal from the surface (i.e. has an acoustic release). You can imagine how much attention is paid to where the boat is positioned and how intently we are all waiting, looking for the device to surface.

Marine megafauna sighted to date include:

• Blue Whales (endangered)
• Sei Whales (endangered)
• Fin Whales (threatened)
• Humpback Whales (of special concern)
• Grey Whales (of special concern however the Committee on the Status of Endangered Wildlife in Canada has recommended three populations be recognized of which two be protected as endangered populations)
• Minke Whales
• Sperm Whales
• Killer Whales (multiple ecotypes, threatened and endangered)
• Short-Finned Pilot Whales
• Risso’s Dolphins
• Cuvier’s Beaked Whales
• Baird’s Beaked Whales
• Pacific White-Sided Dolphins
• Northern Right Whale Dolphins
• Dall’s Porpoises
• Harbour Porpoises (of special concern)
• Northern Elephant Seals
• Steller Sea Lions (of special concern)
• Pacific Harbour Seals
• Northern Fur Seals
• Sea Otters (of special concern)
• Mola mola
• Blue Sharks

The rarest of the rare have not been sighted to date on PRISMM:

• North Pacific Right Whale (endangered)
• Basking Shark (endangered)
• Leatherback Turtle (endangered)

Humans involved in PRISMM:

Additional photos from my two weeks on PRISMM

Sources / related articles: 

Fisheries and Oceans Canada – Wright, B.M., Nichol, L.M., Doniol-Valcroze, T. 2021. Spatial density models of cetaceans in the Canadian Pacific estimated from 2018 ship-based surveys. DFO Can. Sci. Advis. Sec. Res. Doc. 2021/049. viii + 46 p.

Fisheries and Oceans Canada – Pacific Region International Survey of Marine Megafauna (PRISMM)

Global News, September 26, 2018, Endangered sei whales spotted in Canadian waters for first time since 1960s

The Conversation, January 10, 2017, New US seafood rule shows global trade and conservation can work together 

Vancouver Sun, April 11, 2018, Ottawa undertakes massive cetacean survey off B.C. coast to ensure continued fish exports to U.S 

R. Williams, M. G. Burgess, E. Ashe, S. D. Gaines, R. R. Reeves. U.S. seafood import restriction presents opportunity and risk. Science, 2016; 354 (6318): 1372 DOI: 10.1126/science.aai8222