1. Institute for Agricultural and Fisheries Research www.ilvo.vlaanderen.be Agriculture and Fisheries Policy Area Institute for Agricultural and Fisheries Research ICES - SG Electra – 21/04/2012 Work on effects of electric fishing on various marine organisms Marieke Desender & Maarten Soetaert

2. 2 Introduction Pulse trawl brown shrimp – Marieke Desender Evaluation of impact on marine biota Boundaries electrofishing – Maarten Soetaert

3. ILVO, an ocean of opportunity 3 State of the art Little known about impact of the Hovercran pulse Paper (1) : – Sole, plaice, cod, dragonet, fivebeard rockling, pogge and armed bullhead – Exposure: 10s – Short-term effects (<24u)  No injury (1) : Vercouteren et al., 2011, ‘Short-term effects of low frequency pulsed direct current on captive-housed sea fish’, submitted

4. ILVO, an ocean of opportunity 4 Gaps? Electrosensitive fish and invertebrates? Embryo’s, Larvae & juveniles? Long-term effect?

5. ILVO, an ocean of opportunity 5 Research WP1: reaction of electrosensitive fish? – In a heterogeneous electric field – Dogfish and thornback ray Electrotaxis: 1 Swimming up: 9 – Euthanise: After 1 & 14 days – Autopsie Macroscopic Histological Rx

6. ILVO, an ocean of opportunity 6 Research WP2 exposure in a homogeneous field: – Catshark, thornback ray and sandworm – exposure (5s) to 75, 150 V/m?: 2 plate shaped electrodes Orientation! – Behaviour analysis Video-tracking software: Noldus Activity and apatite – Euthanise After 1 and 14 days – Autopsie Macroscopic RX Histology

7. ILVO, an ocean of opportunity 7 Research WP3: Exposure eggs, larvae and juveniles – Cod, sole, sandworm and brown shrimp Exposure to fieldstrengths of 75 and 150 V/m – 3 egg stages – 2 larval stages – 1 juvenile stage Parameters – Mortality – # hatched – Malformations – Growth, Yolk resorption – Histology

8. Institute for Agricultural and Fisheries Research www.ilvo.vlaanderen.be Agriculture and Fisheries Policy Area Institute for Agricultural and Fisheries Research Questions, suggestions?