Poor out­look for caplin this year: DFO

Caplin fish­ery does not neg­a­tively af­fect caplin abun­dance, sci­en­tist says

The Beacon (Gander) - - Editorial - BY GLEN WHIFFEN glen.whiffen@thetele­gram.com

From a whole school of per­spec­tives, caplin are prob­a­bly in a class of their own as the most im­por­tant for­age species in the wa­ters around New­found­land and Labrador.

A favoured food for the likes of cod, seals, seabirds and whales, and a bunch of other ocean preda­tors, the caplin that make it through to early sum­mer are also hit by the com­mer­cial fish­ery as they pre­pare to spawn.

The De­part­ment of Fish­eries and Oceans (DFO) says up to a mil­lion tonnes of caplin are taken an­nu­ally through nat­u­ral pre­da­tion, while the com­mer­cial fish­ery’s re­movals are small and barely im­pact stock lev­els.

Even more than con­sump­tion and re­movals, the state of the en­vi­ron­ment ap­pears to be the big­gest fac­tor af­fect­ing caplin abun­dance, which doesn’t look good for the next two years.

“En­vi­ron­men­tal con­di­tions are the main de­ter­mi­nant of caplin abun­dance,” DFO fish­eries bi­ol­o­gist Fran Mow­bray said March 12 dur­ing a tech­ni­cal brief­ing for mem­bers of the me­dia.

“Strong year classes can be pro­duced from a small stock when en­vi­ron­men­tal con­di­tions are favourable for fish lar­val sur­vival, and vice versa. This is why we see a lot of vari­abil­ity in the stock.”

Other than a brief pe­riod of more moder­ate caplin stock lev­els ob­served from 2013-2015, cur­rent stock lev­els have re­turned to the low lev­els typ­i­cal of the post-1991 pe­riod, Mow­bray said.

“Spawn­ing times since 2015 have been de­layed,” Mow­bray said. “Late spawn­ing is as­so­ci­ated with poor lar­val sur­vival.”

The spring acous­tic abun­dance in­dex in 2017 de­clined 70 per cent from 2015 num­bers, Mow­bray noted, pro­vid­ing a poor out­look for the caplin stock in 2018 and 2019.

As well, the size com­po­si­tion of caplin landed in the com­mer­cial fish­ery de­clined in 2017, largely due to a high pro­por­tion of Age 2 spawn­ers. This was con­sis­tent with ob­ser­va­tions in the spring 2017 acous­tic sur­vey, she noted.

Since the early 1990s col­lapse of ground­fish stocks in the prov­ince, there have been many who main­tained that the caplin fish­ery should have been closed un­til ground­fish stocks re­cov­ered.

A caplin fish­ery, how­ever, has con­tin­ued.

Land­ings of caplin in the prov­ince in the last three years were 23,065 tonnes in 2015; 27,708 tonnes in 2016; and 19,917 tonnes in 2017. The year 2016 was the only one of the three in which fish­er­men came close to tak­ing the to­tal al­low­able catch (TAC) set by DFO. Fish­er­men took 97 per cent of the TAC that year. The per­cent­age of the TAC taken in 2015 was 81 per cent, while 70 per cent of the TAC was taken in 2017.

“At this point in time we don’t have ev­i­dence that re­movals of the fish­ery are driv­ing (low abun­dance),” Mow­bray said. “All re­viewed in­for­ma­tion in­di­cates that the year class strength of caplin is pri­mar­ily im­pacted by en­vi­ron­men­tal con­di­tions.

“There are things that we’ve come to un­der­stand about what gen­er­ates caplin. There’s re­ally no re­la­tion­ship be­tween the num­ber of caplin that spawn and the num­ber of lar­vae that are hatched from those eggs.

“Con­sump­tion within the ecosys­tem hap­pens through­out the year, it doesn’t just hap­pen in the one week prior to spawn­ing as when the com­mer­cial fish­ery hap­pens. The com­mer­cial fish­ery wants the best bang for the buck, when roe con­tent is high and when the caplin are not feed­ing. Caplin feed quite ag­gres­sively dur­ing the spring right up to about a week be­fore spawn­ing, so the com­mer­cial fish­ery doesn’t open un­til a week be­fore spawn­ing. It’s a very min­i­mal im­pact.”

An­other thing of note is that fish­eries pro­duc­tiv­ity on the New­found­land shelf has de­clined since the early to mid-2010s, Mow­bray said. This de­cline was ini­tially as­so­ci­ated with the loss of shell­fish and in the last two years in­cludes de­clines in pis­ci­vores (fish that eat other fish). De­spite this de­cline in preda­tors, the in­dex of fish pre­da­tion on caplin in­creased in 2016 and 2017.

DFO as­sesses caplin mainly in fish­ing zone 2J3KL off the prov­ince’s east and north­east coast. The stock is as­sessed us­ing in­dex sur­veys of lar­val caplin and an acous­tic sur­vey of mostly im­ma­ture (Age 2) caplin.

The caplin lar­val in­dex is de­rived from sam­pling con­ducted in Trin­ity Bay, while the acous­tic sur­vey is con­ducted dur­ing May in fish­ing zone 3L. This sur­vey cov­ers the pri­mary dis­tri­bu­tion area of Age 1 and Age 2 caplin.

Mow­bray said that start­ing this year, DFO will carry out caplin as­sess­ments on an an­nual cy­cle in­stead of the pre­vi­ous two-year cy­cle.

In the com­ing weeks, DFO fish­eries man­age­ment will hold con­sul­ta­tions with fish­ery stake­hold­ers and Indige­nous groups through­out the prov­ince. The TAC and any other man­age­ment ac­tions will be an­nounced fol­low­ing the con­sul­ta­tions.

GLEN WHIFFEN/THE TELE­GRAM

DFO fish­eries bi­ol­o­gist Fran Mow­bray pro­vides an up­date on the state of caplin stocks to mem­bers of the me­dia in St. John’s March 12.

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