Euphausiid Research

Scientific research has been ongoing since the beginning of the euphausiid fishery in the early 1970's in B.C. However, very little published information is available on these endeavours.

Between 1994 and 1996, acoustical mapping surveys with verification tows were conducted by the Science Branch in Jervis Inlet and Malaspina Strait areas during October and November prior to fishing and again in January and February after fishing. Also, between June 1994 and August 1995, joint departmental and industry monthly surveys were conducted with support from external funding. The results of these surveys are published as a PSARC paper and indicate that the present harvest levels are a small fraction of annual average standing stock (D. Mackas, 1996, personal communication).

In 1998, department staff from the Institute of Ocean Sciences carried out four biomass and distribution surveys in the Strait of Georgia between Turn Point in the Sidney area, and Cape Mudge near Campbell River.  The surveys included assessments in the Malaspina Strait and Lower Jervis Inlet areas where the majority of commercial harvest occurs. These surveys were hydroacoustical assessments, performed during daylight hours in February, March, July, and October using standard gear from Canadian Coast Guard (CCG) research vessels. Preliminary results suggest biomass estimates 10 to 15% below the estimates derived from surveys conducted in 1997 (S. Romaine, 2000, personal communication). These results appear to contradict the improved yields and record high catch per unit effort observed in the 1998 commercial fishery.

Surveys have been conducted in the Strait of Georgia from 1997 to 2000 to estimate the abundance of euphausiids using hydroacoustic technology. In April 2000 values for the central Strait of Georgia were estimated at 914,200 tonnes (±51,500) wet weight and August 2000 were estimated at 1,162,400 tonnes (±11,200).  Euphausiid concentrations during 2000 were among the highest recorded over the last decade and almost double that of 1999 (Romaine et. al, 2001). These survey results indicate that the total allowable catch (TAC) of 500 tonnes is less than 1% of the total biomass estimate in 1997 and as low as a fraction of a percentage of the estimated biomass in 1999 and 2000.

Scientific research with joint industry, First Nations, and Department involvement is important to justify the low level impact of this fishery as it moves from a precautionary management regime towards a biologically based fishery.