vrijdag 27 maart 2015

1st and 2nd Hauls

Wednesday 25th 2015          

Despite the fog and overcast weather the sea remained generally calmer today. This, as hoped, has reduced the interference on the echograms. Which made everyone very happy. Today we also had our first haul on blue whiting – estimated to be around 4000 kg, containing mostly smaller sized fish. By-catch was very low consisting of just two hake (Merluccius merluccius) and one greater argentine (Argentina silus). 

First haul of blue whiting.

Once the blue whiting are separated from by-catch a sub-sample is taken. The length and weight of these fish are recorded and sex is determined by inspection of the gonads. Otolith are also removed from these fish for ageing

Blue whiting organised into size classes.
Thursday 26th 2015

Today started off relatively quiet with a small number of blue whiting being detected on the echograms. Fish began to appear in larger numbers around 13:00 and we decided to fish. This haul contained a greater range of species compared to the first, including a variety of lantern fish species (Myctophidae) – a family of fish which contribute significantly to the fish biomass in the ocean (some estimates suggest it could be as much as 60%). A handful of hatchet fish (belonging to the family Sternoptychidae) were also caught and a pair of deep sea squid.

Hatchet fish
Stephanie weighing up the jellyfish.
Lantern fish.
Deep sea squid.

Later that evening we received news of yet another cruise track change with additional CTD stations. The Russian vessel still has not received permission to enter the 200 nautical mile zone around the UK and so several of our transects have been extended to help cover this area. The same applies for the Irish and Norwegian vessels.

Another change of cruise track with additional CTD stations.

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