Thursday, November 3, 2016

A MATTER OF EFFORT

Anglers in New York and Connecticut, as well as New Jersey, are going to see tougher fluke regulations next year.

For the past six years, fluke have had relatively poor spawning success.  As a result, the National Marine Fisheries Service will reduce the 2017 annual catch limit by 30%.  That, in itself, would impact regulations, and the fact that, coastwide, anglers seem to be landing more fish than they had in 2015 is going to mean that regulations will have to be tightened a little more.

The big question is how much landings in those states will have to be cut.

If the Atlantic States Marine Fisheries Commission continues with a regional management system, in which Connecticut, New York and most of New Jersey fish under the same set of rules, things will be bad enough.  However, if the regional management system is discarded, and a state-by-state management system put back in place (something that, hopefully, will not occur) the cuts in New York and Connecticut will be extremely severe.

NMFS estimates that, during the first eight months of this year, New York anglers harvested more than 710,000 summer flounder—nearly twice the 368,000 landed during the same period last year.  Proportionately, Connecticut did even worse, with 2016 landings through August 2016 more than 250% of what they were for the first eight months of 2015.  However, in a regional management system, New Jersey’s 2016 landings provide a sort of buffer, with the 615,000 fish landed this year only about one-third higher than were landed, for the same 8-month period, in the year before.

Before going much farther, it probably makes sense to remind folks of how those recreational landings were calculated.

NMFS estimates of recreational harvest result from a combination of two different processes.  The first is the estimate of catch, which results from in-person interviews.  


“Interviews are conducted in person by trained staff, and the sites and dates are selected by a proportional random selection process such that those sites that have the most activity will be sampled most often…
“From these angler interviews a catch per trip (catch rate) estimate is made for each type of fish encountered, either observed or reported.  These weighted [catch per unit effort] estimates are combined with the weighted effort estimates by sampling stratum to produce the catch and harvest estimates.”
Calculating the catch per trip is pretty straightforward.  NMFS just needs to look into enough coolers to get a good sample, and divide the total number of fish of each species by the number of samples taken.  If, say, they interview 25 people, who put a total of 30 fluke on ice, the average number of fluke landed per trip is 1.2 (there’s a little bit more statistical work than that involved, but for now, I’m keeping it simple).  

Multiply that 1.2 fluke per trip by the number of trips made by the entire angling community, and you come up with a number that should be pretty close to the actual landings.

Of course, first you have to figure out how many trips were actually made.

To do that, NMFS traditionally used the Coastal Household Telephone Survey, in which

“Data collection occurs during a two-week period at the end of each two-month sample period (or “wave”)…
“The [survey] uses a computer-assisted random digit dialing (RDD) approach to contact full-time residential households.  Contacted households are screened to determine if any household members participated in marine recreational fishing during the previous two months, and each active angler is asked to recall the number of saltwater fishing trips that were taken during the wave, as well as provide details about each trip.  Institutional housing, businesses, wireless phones, and pay phones are excluded from the survey.  Within each state, sample is allocated among coastal counties in proportion to household populations.
“Data from the [survey] are used to estimate the average number of trips per household for each coastal county.  These estimates are then expanded by the county household population to estimate total trips.  County estimates are summed and then expanded…to produce state-level effort estimates.”
We happen to be in one of those two-week periods at the end of each wave when samples are taken, so answer quickly—no time to go check your log--how many times did you go fishing in September and October?  

Are you sure?  You know what you did last weekend, and the weekend before, but some of those other trips…Did you really take them all in early September, or were some from late August..?

And that’s the problem with the effort part of the survey.  Sometimes memories get, let’s say, just a little fuzzy…

And that’s a real problem, because effort has a real impact on estimates of recreational catch.

Remember those 710,000 fluke that New York anglers caught in the first eight months of this year?  It turns out that about 610,000 of them were caught by anglers fishing from private boats, and most of those—about 470,000—were caught in Wave 4, July and August. 

Nearly 320,000 of the 368,000 fluke that New York anglers caught in the first eight months of last year were caught by private boat anglers, too, but Wave 4 accounted for a little less than half of them—only about 150,000 fish.  Had Wave 4 produced as many fluke for private boat anglers in 2015 as it did this season, there wouldn’t have been much of a difference in landings between the two years at all.

Thus, the big question is: WHY was Wave 4 harvest so much bigger this year?  And the a big part of the answer to that question is EFFORT.

In 2015, New York’s private boat anglers made slightly fewer than 500,000 fishing trips during Wave 4; this year, that number nearly doubled, to more than 950,000.  It shouldn’t surprise everyone if the number of fluke landed during Wave 4 doubled as well.

In fact, landings actually tripled during that period, so factors other than effort also played a role.  But there can be little doubt that when fishermen make twice as many trips as they did the year before, the number of fish landed is going to increase.  A lot.

In the back of my mind, I can already hear the objections to upcoming harvest reductions.  Someone—more likely many someones—will get up at meetings and declaim that “There’s no way New York anglers caught triple the fluke this July and August that they caught during the same time last year.”  And if someone shows them the effort numbers, they’ll continue to object, saying “And there’s no way that people made twice as many trips this summer than they made last year."

And when they say that, they may very well be right, just not in the way that they intended.

Over the past 10 years, New York anglers averaged somewhere around 1 million saltwater fishing trips during the months of July and August.  That figure peaked at more than 1,500,000 trips in 2008, and is trending down somewhat, but only dropped below 900,000 twice in the last decade—once in 2013, when it fell to around 750,000 trips, and last season, when it dropped to less than 500,000.

Thus, if there was any error in the effort estimates, it’s likely that the error involved undercounting the number of trips taken in 2015.  The 950,000 trips estimated for this July and August represented a return to the norm, rather than a gross deviation.

But in other years, effort has seemed unreasonably high.  It’s just a very difficult figure to pin down with any confidence.

Fortunately, NMFS is taking steps to improve effort estimates.  The telephone survey, which randomly targets households in coastal counties, is being replaced by a new Fishing Effort Survey that will mail written surveys, primarily to households where anglers are known to live.  Time and resources will no longer be wasted contacting households where no one fishes; the far higher percentages of positive responses will, in and of itself, substantially reduce the error from that inherent in the phone survey.  

In addition, by employing mail rather than a telephone call, anglers will be better able to provide accurate information about the number of trips taken, using their logs and other aids to memory not available during the course of a brief phone conversation.

The new survey should be fully in place by the 2018 season.  


In the meantime, anglers concerned with the accuracy of catch estimates should be reassured by the fact that NMFS is making a serious effort to get the effort data right. 

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