Thursday, July 21, 2016
BY THE NUMBERS
If you’ve gone to enough fisheries management meetings, you know the routine.
First, biologists will address the public, and describe the state of the stock, providing numbers for biomass, recruitment and fishing mortality. They’ll then recommend regulations that, they believe, will prevent overfishing and allow the stock to rebuild or, if the stock has already reached its biomass target, maintain it at sustainable levels.
At that point, the debate begins.
Inevitably, someone—generally someone with no background in either science or statistics—will rise to critique the stock assessment, supporting his position with arguments like
“Your numbers are no good. You don’t know what you’re talking about. You just sit behind a desk while we’re out on the water every day. There’s plenty of fish out there. Come out with us, and we’ll show you how to catch ‘em. You shouldn’t be trying to cut back our harvest; there’s so many fish out there, you should be letting us catch more!”
It doesn’t matter too much where you are or what species you’re talking about; Gulf of Maine cod, mid-Atlantic black sea bass or South Atlantic red snapper, when you go to a meeting, they all sound just about the same.
It might be useful, then, to take a look at some recent stock assessments, and compare them to what is really going on out on the water. I’m going to limit my comments to species commonly found in my home waters off Long island, because I follow those fish more closely, and can more easily provide reports of what’s going on.
I’ll start with scup—our northern porgy—because that’s one of the easiest fisheries to address. It was considered a data-poor fishery as recently as 2008. For a while, it gave managers a hard time; fish were sparse and small. Biomass bottomed out around 4,000 metric tons during the mid-1990s.
Fortunately, a good stock assessment model was finally devised, and the Mid-Atlantic Fishery Management Council implemented a rebuilding plan that was so wildly successful that a benchmark stock assessment released in 2015 reported that
“Spawning stock biomass (SSB) was estimated to be 182,915 mt in 2014, about 2 times the…biomass reference point SSBMSY Proxy = SSB40% = 87,302 mt.”
If the stock is truly twice the size of the biomass target, anglers should be catching plenty of scup, and that’s exactly what’s happening. A report in a Riverhead, New York publication was typical:
“The bite was all day long. As soon as things slowed, we would just move to find another pile of fish. Toward the end of the day, the wind turned south and picked up quite a bit. This worked like a dinner bell for the porgies. The bite ramped up to lights out status…”
So it certainly seems like the biologists got their scup numbers right.
But maybe scup are too easy, because there are plenty around. The numbers for other popular species, such as fluke and striped bass, aren’t quite so optimistic. Did the scientists get those right as well?
There was quite a bit of displeasure last year when managers announced that the 2016 recreational summer flounder catch limit was going to be substantially reduced. Brook Koeneke, who operates a New Jersey party boat, reportedly had a predictable reaction to the news.
“I’m convinced that they don’t know what they’re talking about. We see a lot of flounder. We raised the (size) limit and saved a lot of fish. It looks like it recovered and then the next year they say we have a problem.”
So the question is, just why do managers believe that a problem exists?
It turns out that the problem was a combination of overfishing and poor recruitment. For four consecutive years, 2010 through 2013, the number of young-of-the-year summer flounder entering the population was well below average. Harvest had to be reduced, because flounder removed from the stock today won’t be replaced by new fish recruiting into the fishery next year.
Do anglers’ experience on the water reflect what the scientists believe to be true?
It apparently does. Early June is peak time for fluke in Connecticut waters, but a report put out by the state’s Department of Energy and Environmental Protection on June 2 rates the fishing as only “fair to good.” A New Jersey report from the same time period also talks about summer flounder fishing being “spotty at best,” and “very hit or miss.” Another section of the same report says that fluke fishing in southern New Jersey is “not what it has been in some other early Junes.”
My own success with summer flounder has been far below average this season, with few fish being caught on what are typically productive drops. A charter boat captain from Montauk whom I often speak with tells me that he is seeing a good number of large fluke, but not many smaller ones, which would be typical of a fishery with poor recent recruitment, that is forcing anglers to depend, at least in part, on the bigger, older survivors of the larger year classes produced in 2008 and 2009.
Once again, what’s happening on the water seems to match the biologists’ predictions.
And finally, we come to striped bass.
Chesapeake Bay produced big year classes in 1993, 1996, 2001, 2003, 2011 and 2015. In the Hudson River, 2007 produced a very strong year class, and I have been told by folks at the New York State Department of Environmental Conservation that 2014 was above-average, as well.
At the same time, a 2015 update to the striped bass stock assessment said that there was a 49% chance that the stock could have become overfished last year. So while we’ve seen some strong year classes, the overall population is not at a high level of abundance.
So what do anglers see on the water?
Over all, experienced anglers are seeing a real decline in the number of fish available. At the same time, a lot of big fish are being caught, including a 62-pounder that hit a trolled bunker spoon east of New York’s Fire Island Inlet. However, there aren’t a lot of fish in one place. When action was hot in New York Bight, it was slow farther east on Long Island. Later in June, the big-fish action moved into my region of South Shore Long Island, but waned to the west while Montauk remained dead.
Now, bass have disappeared almost completely on the central South Shore, but have settled in at Montauk and Block Island, with one party boat operator reporting
“EPIC striped bass fishing aboard the Viking Starship tonight. We had a sold out crowd and our anglers enjoyed and our anglers enjoyed a full boat limit of mighty moo cow Bass! Most fish were in the 25-35 pound class, with a few smaller and a few bigger! …the pool fish [was] a 43.9 pound Behemoth Striped Bass…the second place winner…was 39.8 pounds.”
Again, that’s about what one would expect from the data available. There are only enough bass in the population to provide decent fishing in a few localities, and most of the fish caught can be attributed to one of the big year classes. On the Viking Starship, the majority of the catch, 25 to 35 pound fish, were probably produced by the 2001 and 2003 year classes. The 62-pound fish caught off Fire Island was likely a ’93.
But the smaller fish are showing up, too. Here on Long Island, the 2011 year class began to show up in numbers in 2015, and reports indicate that they were also present up in New England. They were back with a vengeance this spring, particularly in New York Bight and in western Long Island Sound, where the small, 22 to 26-inch fish were joined by a few in the 13 to 18 pound range, which were probably 2007s from the Hudson River. We also saw a lot of menhaden-sized stripers along the western Connecticut shore, which were almost certainly spawned in the Hudson in 201A4.
Once again, the science predicted the sort of striped bass fishing that we’d experience.
That being the case, claims that the biologists’ “numbers are bad” don’t really ring true. The stock assessments and similar data are usually very good predictors of what we will see on the water.
Yes, there are areas of local abundance when populations are down, and places that fish sometimes avoid even when they’re abundant.
But over the long haul, you won’t go very wrong if you predict your likely success based on the numbers that the scientists provide. Although some folks refuse to believe it, those numbers are usually right.