Blog post

First herring catches

Published on
June 29, 2012

Yesterday on Thursday 28.06. at 2:00 UTC we started the first transect of the survey.

4 hours later we already had the first trawl station after spotting a few marks on the echogram at 58º17’N 1º32’W:

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Later in the afternoon, the trawl was again shot a bit further east along the transect at 58º17’N 0º35’E, when 2 biggish marks appeared on the echogram.

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Both catches yielded herring of mean size between 26 and 29 cm.

Today, we are now on the way west again towards the Moray Firth on the second of the 2 main transects we cover this week (indicated in blue):

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Another trawl was done this morning at 58º04’N 0º47’E when we saw a few speckled marks with the odd big pile shaped school amongst them:

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everyone was waiting on the bridge and monitored the catch sensors and trawl sonar to see if any fish were going into the net:

the net was hauled and the catch soon appeared on the conveyor belt ready for Hendrik Jan to take a sample:

the herring samples were then divided into length classes:

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in the meantime, Momo and Willem measured the lengths of other species that were caught (like mackerel):

An interesting thing noted was that even for the older herring, maturation of the gonads can be quite different. Here a few examples of a few herring of 26 cm and larger that showed differences in maturity stages, some immature as well: