Utility of continuous light and triploidy to control sexual maturation of Atlantic cod in the Bay of Fundy

Description

Early maturation in pre-market Atlantic cod affects ~100% of fish in sea cages, and this problem is not isolated to the Bay of Fundy. Preliminary results from 24 h light treatment (six 400 W submerged lights) in a 70 m polar circle cage holding 2004 YC cod support the hypothesis that continuous light delays onset of sexual maturity, in this case by ~ 4-5 months, with females subsequently retaining the state of ripeness for another 4 months (ACRDP project MG-04-09-001).

The current proposal will explore two approaches to impede sexual maturation:

1. continued experimentation with light level and wavelength and
2. induction of sterility by triploidy.

This study has six objectives:

1. To further evaluate on-going light treatments and test the use of new light technology to inhibit sexual maturation of Atlantic cod.
2. To examine the degree of suppression of maturation in both sexes in 0+ group, pre-market and market fish exposed to 24 h light.
3. To develop protocols for the pressure-induced production and early identification of triploid cod.
4. To monitor seasonal sex-specific growth of immature and mature cod (derived from light treatments and triploidy) as well as incidence of deformities and mortality.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)

Year(s)

2007 - 2010

Ecoregion(s)

Atlantic: Gulf of Maine, Scotian Shelf

Principal Investigator(s)

Edward Trippel
Email: Edward.Trippel@dfo-mpo.gc.ca