Aquaculture in Virginia

A student in a previous class asked:
> Can anyone tell me, is overharvesting when the fisherman take too much
> fish (oysters, blue crabs) out of the water?

It was a good question - and the answer is yes. From a scientific perspective, typical farming and timber harvesting is not that different from harvesting shad, menhaden, crabs, or oysters. From an economic and political perspective, however, there's a world of difference.

Foresters can grow a new crop of trees in 100 years, or less. They can estimate the tree growth in Virginia's climate, and on their soils. They can then schedule timber cutting on their particular lands so each year, they harvest 1% of the woods owned by the company. After 100 years, when they get around to the first 1%, it's grown back and is "ripe" for harvest.

That's a conservative schedule, one that might emphasize soil conservation, wildlife, and recreation values more than the value of wood fiber. Pines grow much faster in the coastal plain, compared to oaks and hickories in the mountainous regions. For some species and in warmer climates, the rotation can be as fast as 10 years. Foresters near the West Point or Franklin pulp mills can harvest a crop of pine trees perhaps once a decade - not as fast as farmers harvesting corn or peanuts once a year, or cutting hay two-three times a year, but trees take longer to reach commercial size...

It's a lot easier to estimate how many trees are present on a company's timberland, and how fast they are gowing through drought years or good years. Trees don't move; you can even use photography to calculate the status of a forest health. Estimating the number of fish - and how fast they are actually growing each year - is as much an art as it is science. Watermen who need a large harvest to make enough money to pay off the loan on the boat always seem to estimate a large population. It's not surprising that population projections are affected by economics - on resource management issues, scientific judgement may refect economic perspectives, and it's an old saying that "where you stand on an issue depends on where you sit."

Also, an investment in a forest inventory make more sense to a private landowner than an inventory of aquatic resources by a waterman living on the bay. Westvaco, Georgia Pacific, and other timber companies in Virginia harvest on only their lands, or on lands owned by other private landowners who have been paid for the standing timber, or on National Forest lands where the Federal government has sold the rights to cut the timber on a specific site.

Who owns the water in the Chesapeake, or the Atlantic Ocean, where the fish are swimming? The aquatic resources such as fish are "here today - gone tomorrow." Why count and conserve, when a fisherman may get no benefits from waiting until later? It's hard for one waterman to stockpile fish for harvest later... those fish may be caught by someone else. Since crabs, fish, even oyster larvae migrate, any conservation by Virginians might increase a harvest in Maryland, Delaware, North Carolina - so any limits on harvest need to be coordinated with adjacent states, or Virginia would have no incentive.

The natural tendency is for individual fisherment to harvest as many as you can, while they can, rather than to allow someone else to benefit from their restraint. If the race to harvest now leaves too few fish in the region for spawning and creating a new "crop" - well, tomorrow is another day. Fisherment in Virginia can always blame the shortage on overharvest n=by Maryland fishermen, or on the drought, or on the chicken growers polluting the rivers, or... whatever, just so long as "our" harvest is not limited because of concerns about overfishing. After all, we Virginians are all conservation-minded, and overharvest is what the _other_ guys do - right?

Harvest of aquatic resources is one of the few commercial operations still based on the old "hunting and gathering" approach. There are exceptions, in a fewcases because interstate compacts sponsored by the Federal government balance the benefits with the costs of conservation. One obvious exception to the pattern is the management of leased oyster beds. A waterman who controls the right to harvest can afford to wait until the oysters are older and bigger. Such patience may lead to a higher return on investment, assuming disease, fresh water from a hurricane, or theft do not reduce the population first.

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