Sunday, October 4, 2015


We were at a meeting of New York’s Marine Resources Advisory Council, sitting around a table and talking about whelks.

No, don’t stop reading…

Because in the end, biology is biology, and broad principles that apply to one species probably apply to others, whether or not they have shells.

At any rate, it appears that a lot of folks have been fishing for whelks in recent years, impelled by both a dearth of lobsters south of New England and a solid Asian market that’s keeping the prices higher than they were when whelks were only being sold for scungilli and the market was pretty small.

Fisheries managers from Massachusetts and Virginia have become concerned that too many whelk are being taken too soon, and that the number of mature whelk, which constitute the spawning stock, is falling too low.  As a result, every state in the region, except for New York and Connecticut, have adopted some sort of minimum size regulations.

New York is contemplating a minimum size as well, and that’s what we were talking about at MRAC that day.

As usual, the fishermen were objecting to any new rules, arguing that the data presented by state biologists were too uncertain to justify to restrictions, that fishermen were seeing plenty of whelks, that whelks in western Long Island Sound were reproducing just fine at smaller sizes, that…well, you get the idea.

The state admitted that its data was far from complete, but everything it had was pointed in the same direction—the average size of whelks was declining, too many were taken before they matured and, because of that, the whelks were headed for very rough times if the current trends continued.

The fishermen said that without better data, regulations impacting their incomes should not be adopted.

I finally pointed out that when data is slim, and managers only have a vague idea about safe harvest levels, regulations should incorporate far more precaution than might be required when managers have a more complete picture.

One of my MRAC colleagues immediately responded,
“Yes, because using precaution worked so well with black sea bass…”

He was trying to be sarcastic, suggesting that managers were somehow wrong in not allowing a bigger black sea bass harvest given the species' of apparent abundance, and would be equally wrong taking a precautionary approach with the whelks.

But the fact is, precaution is working well with black sea bass.

There seems to be a lot of black sea bass out there right now, largely because of a dominant 2011 year class.  There were certainly plenty of fish here off Long Island when the season opened last July.

But at the same time, fish such as black sea bass, which tend to bunch up on structure, can often seem more abundant than they actually are.  

The same wreck or artificial reef that teems with decent-sized sea bass when the season opens can seem pretty picked-over a month later; by this time of year, it’s very tough for anyone fishing one of the reefs off Long Island’s South Shore to put together a limit of fish.

The quick decline of the inshore fishery makes thoughtful anglers wonder whether there really are so many sea bass out there.

So maybe, when dealing with such data-poor species, a little precaution is warranted.  It’s better to kill a few less fish, and keep the stock healthy, rather than take more than we should and have to begin the rebuilding all over again.

I was thinking about such things last week, when I attended the Mid-Atlantic Fishery Management Council’s scoping meeting for forage fish here on Long Island.

Forage fish are the glue that holds the food web together, the myriad small, plankton-eating fish that serve as food for everything from scup and summer flounder to the great whales.  

There are a number of important forage fish species; some, such as Atlantic mackerel and menhaden, support large commercial fisheries; biologists have at least some idea of their basic biology and how heavily they may be fished without causing problems.

But there are others—fish such as bay anchovy, sand eels and silversides—that don’t support large fisheries and, as a result, have been largely ignored by fisheries managers.  The amount of information that scientists have on such species would make black sea bass seem well-understood by comparison.

And it’s not just the forage species’ biology that we don’t know.  We also have no idea how many forage fish, of how many different species, are needed to maintain healthy populations of the fish sought by sport and commercial fishermen—not to mention how many are needed to maintain healthy populations of birds and marine mammals, all of which depend on abundant forage fish stocks.

Let’s put it this way:  Last summer, there was a big mass of sand eels about 40 or 45 miles southeast of Fire Island Inlet, New York.  

When I say “a big mass,” I’m talking about a layer of sand eels more than 120 feet thick, that extended for miles.  

Those sand eels held huge numbers of false albacore, skipjack and yellowfin tuna, along with some bluefin tuna, sharks and some scattered dolphin (of the mahi sort) and wahoo—plus shoals of cow-nosed rays, all sorts of (warm-blooded) dolphin, fin, minke and humpback whales and various sea birds.

If those sand eels weren’t there, none of the predators would have been there, either.

And the fishing would not have been good.

So it makes sense to protect the forage, even though we might not be quite sure how to go about doing that.

Again, there’s a need for precaution—and a lot of it, because if the forage fish crash, they can bring down the big fish that eat them as well.

So how much precaution is needed?

At the scoping meeting, I came up with a formula.  I told the Mid-Atlantic Fishery Management Council representative that

“The amount of precaution needed to manage a stock is inversely proportional to the amount of data available to fisheries managers.”

Which means that for data-poor species such as black sea bass and the whelks, a lot of precaution is needed.

And for species such as the various forage fish, where data is effectively absent, the highest levels of precaution must be employed.  It wouldn’t be unreasonable to prohibit any increase in harvest unless fishermen first make a clear and convincing case that such harvest will do no harm at all.

Yes, maybe that means that we forego some harvest that we otherwise could have enjoyed.

But as black sea bass teach us, it’s fine to be a little too careful, and fish on a healthy stock year after year.

That's far better than to be overly profligate in even one season, and risk catching nothing at all later on.

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