Norway lobster. Photo: Valentina Melli

Trawl-modifications may improve Norway lobster fishery

Monday 18 Feb 19


Valentina Melli
PhD Student
DTU Aqua


Ludvig Ahm Krag
Senior Researcher
DTU Aqua
+45 21 31 64 57

Time & Place

Tuesday 26 February 2019 at 10.30 a.m.

DTU Aqua, Willemoesvej 2, 9850 Hirtshals

The thesis

A copy of the thesis "Identifying simple and cost-effective gear solutions for an effective implementation of the new EU Common Fisheries Policy (CFP)" is available for reading at DTU Aqua. Please, contact Rikke Hansen,

Modifications in front of and inside the trawl can help the Norway lobster mixed trawl fishery coping with new EU landing obligation, concludes PhD thesis.

The Norway lobster trawl fishery has a high rate of unwanted bycatch, and the fishery is challenged by the EU Landing Obligation, which bans discard of unwanted catch. 

During the last three years, PhD Student Valentina Melli from DTU Aqua has worked on developing and testing different modifications to the trawls used in the Danish Norway lobster fishery. On 26 February 2019, she will defend her PhD thesis. 

Valentina Melli and colleagues are the first to test whether diagonal lines placed in the herding area in front of a Norway lobster trawl will scare unwanted fish species away before they reach the trawl. This solution has proven to be effective to avoid some species, such as haddock, whiting and, to a less extent, cod. 

Far from all fish can be scared away from being caught. To reduce the time that fishermen must spend on sorting the catch, Valentina Melli and her colleagues have investigated how well fish species can be separated from Norway lobsters, once inside the trawl, by dividing the trawl into two compartments. They found that it is possible to separate the majority of the fish into a different compartment, but also that this separation cannot be further improved by using LED lights, moving lines with floats or chains. 

Furthermore, Valentina Melli has used a theoretical method to predict which combinations of gear solutions would be more useful for the Danish Norway lobster trawl fishery. Future research should determine the accuracy of these predictions.

About the defence

Valentina Melli will defend her PhD thesis "Identifying simple and cost-effective gear solutions for an effective implementation of the new EU Common Fisheries Policy (CFP)" on Tuesday 26 February 2019. The defence takes place at 10.30 at DTU Aqua, Willemoesvej 2, 9850 Hirtshals. 


  • Principal supervisor: Senior Researcher Ludvig Ahm Krag, DTU Aqua
  • Co supervisors: Professor Henrik Gislason and Researcher Junita Diana Karlsen, DTU Aqua


  • Senior Researcher Finbarr O’Neill, DTU Aqua
  • Senior Researcher Manu Sistiaga, SINTEF Fisheries and Aquaculture, Norway
  • Senior Researcher Michael Breen, Institute of Marine Research, Norway

Chairperson at defence

  • Associate Professor Peter Vilhelm Skov, DTU Aqua