Hunter - Prey on the Oceans

Global public enthusiasm for the cause of global warming has certainly kept the pot boiling. It has also shown that it is possible to get a global consensus in support of public policy that represents common benefit. For instance, my own province has seen fit to impose a fairly well thought out carbon tax that appears to be well accepted. This was possible only because of the overwhelming consensus in place.

There is one other major global ongoing crisis that we dearly need to address on an emergency basis. I am speaking to the unstoppable fishing pressure been put on our global fishing stocks. I have already showed my readers how the application of a simple hunter predator model to the issue of Arctic sea ice very nicely predicts the catastrophic collapse we are now witnessing.

The same effect has wiped out fishery after fishery and now threatens the tuna fishery. And our mathematically illiterate participants will babble platitudes to the last guppy to protect their right to the fishing status quo. Yet managed global practice could maximize global production on a sustainable basis.

It is a great tragedy that the Grand Banks cod fishery is extinct. Yet it could have been averted, but every player fought tooth and nail to bring in that last boat load. Now they can wait a thousand years in the hope that a recovery is possible. There are still idiots who want to sail out at every rumor a slight increase in stocks.

The principal lesson that can be drawn from a hunter gatherer model is that the take from hunting must absolutely be brought down below the level of theoretical maintenance. In fact if the stock is not at an optimal level in the first place, then the take must be much lower still.

An optimal level is that level attained which does not overload the carrying capacity of the environment itself. This flaw was demonstrated by the caribou herds of Northern Quebec in particular. They would eventually reach the point of eating themselves out of house and home, resulting in their decimation.

Simple herd management could easily prevent that while producing a large annual harvest of surplus males.

The best thing that ever happened to the salmon fishery was the onset of fish farming. A lot of the wild fishery has been curtailed in the process while market demand is now been satisfied. Something like that is working into the tuna industry. I personally would like to see all wild fisheries ended where farm replacement is possible. This would allow a recovery process. Of course, the farmed fish business is also evolving into an efficient and ecologically neutral system, though problems have of course appeared.

The only proper harvesting strategy is that which sees full annual recovery. Any approach other than that will start a depletion cycle that is driven by the insistent demand of the harvesters to maintain a constant take.

That is what is impossible once you even briefly allow the stock to drop slightly below the twelve month recovery point.

With fish there are plenty of variations of harvesting strategies that affect final outcomes that will need to be studied over time. My favorite is the establishment of sanctuary zones that naturally push excess from a healthy core stock out into the fishing zone. This can be applied for a range of species. An example would be the broad reestablishment of the sea otter on the west coast (and perhaps the east coast were it was never native) allowing the rebuilding of huge kelp forests that act as fish nurseries and havens.

Remember that stock recovery works on the basis of compound interest in its natural state until it outruns its resource base. This is often described in terms of the time required to double the size of the stock. If that time frame is say ten years, then reducing the stock by even a small amount is trouble.

This also means that recovery from a collapse becomes extremely problematic. There used to be millions of bison on the Great Plains until we hunted them to near extinction. It has taken most of fifty years of effort to restore the herd back to around 500,000. We could now easily use a herd of 10,000,000 since we have discovered that they are a better deal out on the open prairie. This will take a lot of time still but not nearly as much as the first 500,000. At least the full resources of human ingenuity and capital are working on it.

We have yet to figure out how to do this for the poor cod. Yet I have witnessed the work done in the salmon farm business. I knew guys who pioneered the first facilities and know how unpromising those beginnings were. Today the industry is financially stable and highly productive. We already have salmon available for the price of chicken which was the industries initial promise. It could expand ten fold easily if the market were able to support it.

In fact, the farmed salmon industry surely surpasses the greatest years of the old wild fisheries. And the recovery of that old wild fishery starts with restoration of the spawning rivers. Sewage and fisheries do not coexist.

It will require transnational organizations tasked with ocean management with the authority to enforce agreements similar to the law of the sea. A good start could be the combining of satellite ship identification with aggressive ship arrest protocols. Non compliance would be sufficient to define piracy.

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