Research Document - 2000/026

Witch Flounder Catch Results from Fall 1999 Survey in NAFO Division 3Ps.

By J. McClintock

Abstract

To enhance the fisheries research database in NAFO Division 3Ps, the Groundfish Enterprise Allocation Council (GEAC) has funded surveys during fall 1997, 1998, and 1999 directed at cod and flatfish. The focus in this document is witch flounder. The continuing intent is to create a series of annual fall surveys in 3Ps to complement current resource assessment activities carried out by the Department of Fisheries and Oceans (DFO). GEAC funded and performed the surveys with scientific guidance from DFO in the design and execution of a stratified random survey and the associated sampling. The data collected during these surveys have been subsequently analysed on behalf of GEAC and for the additional intent of providing this information to DFO, for their databases and their assessment work. This is the second GEAC survey to investigate in detail the witch catch (following on the 1998 results in CSAS Research Document 99/59). One trip to perform the 1999 survey was carried out from 22 November to 2 December 1999. These dates match the 8-17 December 1997 and 30 November to 12 December 1998 time periods for the earlier two years. During the 1999 trip, set details and length frequencies were logged in the DFO FFS system and otoliths were collected for subsequent aging. Catch statistics, length and age distribution, and stratified analysis estimates of witch abundance and biomass, including age distribution estimates, and interpretation of results are presented. The 1999 estimate numbers alone indicate a large increase in estimated abundance and biomass from 1998; however, the stability in the age and growth distributions seen argue against inferring any kind of large population increase, rather it is more likely a year effect that is the cause of the increases. Three large sets from one stratum area account for approximately 75% of the total reported 1999 catch.

Complete document (PDF, 416 KB)

Accessibility Notice

This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.