The devastation of the cod off the east coast is an example of
the ecological and social impacts that occur when overexploitation
meets mismanagement of our marine species.
Recent studies have confirmed that even with fishing bans and
attempts at conservation, certain populations of cod are facing
inevitable local extinction (extirpation), while others are
struggling to recover.
The most alarming verdict of the Department of Fisheries and
Oceans (DFO) 2009 stock assessment
reports for cod was for the southern
Gulf of St. Lawrence Atlantic cod. A further analysis of these
findings was published in a study in the Canadian
Journal of Fisheries and Aquatic Sciences in October of 2008.
The study revealed an inevitable disappearance due to high natural
mortality, low recruitment, and the lowest spawning stock biomass
in 60 years, which is expected to decrease even further even with
zero catch. The authors predict extirpation within 40 years with
zero catch and 20 years with fishery removals at the allowed catch
level for 2008-2009.
Why can't the cod recover?
The answer to this question has become complex, differing for
each population and ecosystem, but the reason they have reached the
levels they are today is simple: overexploitation. Even with stocks
at dangerously low levels and most in a collapsed state in Atlantic
Canada, DFO allows fishing in various forms.
For example, for the southern gulf cod, a decreased Total
Allowable Catch (TAC) of 300 tonnes (TAC) was set to cover by-catch
(catch of non-target species) provisions for fisheries targeting
other species, Aboriginal and recreational fisheries, and
scientific surveys. While down from 2,000 tonnes with no directed
fishery (commercial fishery that targets cod), a TAC is still being
set, and this stock is known to be going extinct even with no
The general trends found in all the 2009 stock assessments for
Atlantic cod managed by Canada are that fishing mortality or
exploitation remains above recommended levels for stock
reconstruction and health. The assessments recommend that fishing
mortality must be kept at the lowest possible level, usually
meaning no directed fishery. They also recommend that measures be
in place to reduce the bycatch of cod in other fisheries.
Is there hope?
The results of the northern cod stock
assessment offer some hope for recovery. The northern cod,
which consists of the populations found off southern Labrador and
eastern Newfoundland, suffered the worst collapse of all cod
populations, and one of the worst in fisheries history, reducing
them to less than 1 per cent of their previous level.
Before finding itself a place on Canada's endangered species
list, the northern cod directed fishery was closed by the Canadian
government in July 1992. However, despite a ban, little recovery
has taken place. Although the recent stock assessment indicates
that the number of northern cod is increasing, they remain at only
about 8 per cent of their 1980s level, which is about 1/3 of what
they were in the 1960s.
Despite a ban on commercial fishing, the fisheries have
re-opened and closed over the years. Since 2006 a directed
'stewardship' fishery has been permitted, as well as recreational
fisheries. Perhaps most critically, bycatch is allowed in fisheries
such as winter flounder. Given that the northern cod assessment
states that "there are no management goals against which current
status and trends may be compared; there is no target for
rebuilding, nor is there a target rebuilding rate," there is no
assurance that signs and hope of recovery will turn to long term
sustainability of the population.
Caution: no cod ahead!
We should remain hopeful that the cod will recover, but
continuing a trend of seeking out cod which show any sign of
recovery, shows no foresight. While the situation may be slowly
improving for certain cod stocks, things must be kept in
perspective and past mistakes must not be repeated. We still have a
very long way to go before we are working with sustainable stocks
that can be fished without putting into question the future health
of our cod populations.
Operating as if there's probably no cod is the most
precautionary approach to recovery. When it comes to our cod, a
'stewardship' fishery is a contradiction in terms, we should not be
'playing' with our ailing stocks and lost livelihoods through
recreational fisheries, and any directed fishery is one further
step towards an inevitable fate: a future without Atlantic Canadian
2009 Atlantic cod stock assessment reports:
DFO. 2009. Stock Assessment of
Northern (2J3KL) cod in 2009. DFO Can. Sci. Advis. Sec. Sci. Advis.
DFO. 2009. Cod on the Southern Scotian Shelf and in
the Bay of Fundy (Div. 4X/5Y). DFO Can. Sci. Advis. Sec. Sci.
Advis. Rep. 2009/015.
DFO. 2009. Assessment of cod stock in the northern
Gulf of St. Lawrence (3Pn,4RS) in 2008.
DFO Can. Sci. Advis. Sec., Sci. Advis. Rep. 2009/010.
DFO. 2009. Stock Assessment of Subdivision 3Ps cod.
DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2009/008.
DFO. 2009. Assessment of Cod in the Southern Gulf of
St. Lawrence. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep.
Swain, Douglas P. and Ghislain A. Chouinard. Predicted
extirpation of the dominant demersal fish in a large marine
ecosystem: Altantic cod (Gadus morhua) in the southern Gulf of St.
Lawrence. Can. J. Fish. Aquat. Sci. 65: 2315-2319 (2008)
Hutchings, J.A. 2005. Life history consequences of
overexploitation to population recovery in Northwest Atlantic cod
(Gadus morhua). Can. J. Fish. Aquat. Sci. 62: 824-832.
Baum, Julia K. and Boris Worm.
2009. Cascading top-down effects of changing oceanic predator
Journal of Animal Ecolog.
Myers, R.A., Hutchings, J.A., and Barrowman, N.J. 1996.
Hypotheses for the decline of cod in the North Atlantic. Mar. Ecol.
Prog. Ser. 138: 293-308.
Savenkoff, C., Swain, D.P.,
Hanson, J.M., Castonguay, M., Hammill, M.O., Bourdages, H.,
Morissette, L., and Chabot, D. 2007. Effects of fishing and
predation in a heavily exploited ecosystem: comparing periods
before and after the collapse of groundfish in the southern Gulf of
St. Lawrence (Canada). Ecol. Model. 204: 115-128.
Shelton, P.A., Sinclair, A.F., Chouinard, G.A., Mohn, R., and
Duplisea, D.E. 2006. Fishing under low productivity conditions is
further delaying recovery of Northwest Atlantic cod (Gadus morhua).
Can. J. Fish. Aquat. Sci. 63: 235-238.
Sinclair, A.F. 2001. Natural
mortality of cod (Gadus morhua) in the southern Gulf of St.
Lawrence. ICES J. Mar. Sci. 58: 1-10.
Sinclair, A.F., Swain, D.P., and Hanson, J.M. 2002.
Disentangling the effects of size-selective mortality, density, and
temperature on length-at-age. Can. J. Fish. Aquat. Sci.
Swain, D.P., and Sinclair,
A.F. 2000. Pelagic fishes and the cod recruitment dilemma in the
Northwest Atlantic. Can. J. Fish. Aquat. Sci. 57: 1321-1325.
Swain, D.P., Sinclair, A.F., and Hanson, J.M. 2007. Evolutionary
response to size-selective mortality in an exploited fish
population. Proc. R. Soc. Lond. B Biol. Sci. 274: 1015-1022.
Trzcinski, M.K., Mohn, R., and
Bowen, W.D. 2006. Continued decline of an Atlantic cod population:
how important is gray seal predation? Ecol. Appl. 16: 2276-2292
DFO, 2007. Accounting for Changes in Natural Mortality in Gulf
of St Lawrence Cod Stocks. DFO Can. Sci. Advis. Sec. Sci. Advis.
Le Bris A., Fréchet A.,
Brêthes J.-C. 2009. Estimation of the exploitation rate of
thenorthern Gulf of St. Lawrence (3Pn,4RS) Atlantic Cod (Gadus
morhua) stock, basedon tagging data. DFO Can. Sci. Advis. Sec. Res.
Doc. 2009/012. v + 35p.