Tagged: cod
Donham’s Law of Fisheries Conservation reconfirmed
In an almost perfect illustration of Donham’s Law, the New York Times reports this morning that New English fishermen are pooh-poohing calls from fisheries scientists for greater restrictions, or even an outright ban, on cod fishing in the gulf of Maine.
The scientists point to new data showing cod stocks in much worse shape than previously thought; the fishermen say there’s an abundance of fish.
“Fishermen will almost always tell you that, and it’s not that they’re lying,” said Mark Kurlansky, whose 1997 book, “Cod: A Biography of the Fish That Changed the World,” documented how Canada’s once-abundant Atlantic cod were fished almost to extinction. “Landing a lot of fish can mean the fish are very plentiful, or it can mean the fishermen are extremely efficient in scooping up every last one of them.”
Donham’s Law of Fisheries Conservation states that All fishermen resolutely support conservation measures, except those targeting the species they fish for, and the gear types they fish with.
North Atlantic fisheries, then and now
Scientists at UBC used ecosystem models, underwater terrain maps, fish catch records, and statistical analysis to estimate the biomass of Atlantic fish [large PDF] at various points the last century. David McCandless of the UK Guardian’s Data Blog turned the resulting maps into this animated GIF:
McCandless writes:
These early accounts and data on the past abundance of fish help reveal the magnitude of today’s fish stock declines which are otherwise abstract or invisible.
They also help counter the phenomenon of “shifting environment baselines”. This is when each generation views the environment they remember from their youth as “natural” and normal. Today that means our fishing policies and environmental activism is geared to restoring the oceans to the state we remember they were. That’s considered the environmental baseline.
The problem is, the sea was already heavily exploited when we were young.
So this is a kind of collective social amnesia that allows over-exploitation to creep up and increase decade-by-decade without anyone truly questioning it. Today’s fishing quotas and policies for example are attempting to reset fish stocks to the levels of ten or twenty years ago. But as you can see from the visualization, we were already plenty screwed back then.
Further reading:
- Hundred-year decline of North Atlantic predatory fishes, by Villy Christensen, Sylvie Guenette, Johanna J. Heymans, Carl J. Walters, Reginald Watson, Dirk Zeller, and Daniel Pauly, Fisheries Centre, University of British Columbia. [large PDF]
- The Unnatural History of the Sea, by York University Professor Callum Roberts (Amazon|Chapters|Google Books).
Bounties – reader dissent
Contrarian reader Denis Falvey writes:
A decision that flies in the face of one fact of science does not necessarily constitute ignorance. A bounty may not eradicate coyotes, it may not even lower their numbers appreciably, but it will change their habits. Coyotes live in an ecological niche; like any other animal, they will multiply to fill that niche. I would prefer that the limits on their ecological niche not include my doorstep, and the only way to achieve that is for the animals to be wary of coming near
my doorstep. That’s not going to happen with my singing Kumbayah’. It’s going to happen when animals get used to the idea that my doorstep is not their hunting ground, it’s where they are in danger.
My grandfather would have laughed in dismissal at the thought that vegetables could not be grown in the fields because the deer eat them, or that children can’t play in the woods for fear of coyotes. He was a quiet and peaceful man, but any deer eating the food off his family’s fields would have quickly joined the food on the table, and threats to his children were controlled when necessary. He had a better grasp of living with animals than do a lot of the voices raised against controlling the coyotes. Facts and experience are both important for knowledge, but doing nothing is usually a mistake.
Perhaps we should shift the focus by asking those opposed to support for the trapping industry in this instance what their solution might be. Ignoring the problem, or minimizing it is not an option. Live and let live works about as well with coyotes in the country as it does with gang activity in the city.
I do not advocate doing nothing. Minister MacDonell is a politician. He has to contend with the possibility that a coyote might maul some child, and he cannot be seen to have “done nothing.”
But the action he takes should be based on evidence, and the evidence in Nova Scotia and elsewhere is unequivocal that a bounty will neither reduce coyote numbers, nor change the behavior of the small minority of problem coyotes. Mr. MacDonell’s planned bounty does not target problem animals, or Mr. Falvey’s doorstep. It will not condition coyotes to be wary. You could argue that a general bounty might drive coyotes toward doorsteps, since regulations restrict hunting and trapping near dwellings. Doorsteps will be relatively safe places.
As retired DNR wildlife biologist Bob Bancroft has pointed out, a general bounty targets all coyotes, the vast majority of whom exhibit no problem behavior. This makes the bounty particularly reckless: it uses public funds to target innocent animals with measures that will not impact the few who cause problems.
What might work? MacDonell’s program to train elite trappers to go after problem coyotes is an idea worth trying. The province should consider complementing this with an program to haze animals near populated areas. A dead animal can’t teach pack mates anything, but a coyote that has been frightened or hit by a rubber bullet could increase wariness in a whole pack—particularly if the program were begun now, while coyotes are rearing pups, not delayed until next fall like the useless bounty. The public education program to encourage sensible precautions when interacting with wildlife is also a good idea. We share this planet with other creatures, and that’s a good thing.
But the senseless bounty at the centre of the government’s response represents a flight from evidence-based decisions in favor of pandering to ignorant prejudice.
I suspect the unusually bold behavior we have seen in recent months reflects some change in the food cycle. A surge in coyote numbers may have overtaxed food supplies, so coyotes are hungry, and in a few cases, emboldened. If that’s the case, litter sizes will decrease this spring, the population will fall, food will be less scarce, and problem behavior may ease with or without human intervention.
Last word to Mr. Falvey:
On a lighter note, one solution might be to hand control of the coyotes and deer over to the DFO. They don’t have much to do anymore, and they did rid the oceans of cod in a generation.
