THE N2K GROUP European Economic Interest Group OVERVIEW OF THE POTENTIAL INTERACTIONS AND IMPACTS OF COMMERCIAL FISHING METHODS ON MARINE HABITATS AND SPECIES PROTECTED UNDER THE EU HABITATS DIRECTIVE Contents GLOSSARY................................................................................................................................................3 1. BACKGROUND.................................................................................................................................6 1.1 Fisheries interactions ....................................................................................................................7 2. FISHERIES AND NATURA 2000 - PRESSURES, INTERACTIONS, AND IMPACTS ....................................8 2.1 POTENTIAL PHYSICAL, CHEMICAL AND BIOLOGICAL PRESSURES AND IMPACTS ASSOCIATED WITH COMMERCIAL FISHING METHODS ............................................................................................8 DREDGES .......................................................................................................................................11 TRAWL - PELAGIC ..........................................................................................................................12 HOOK & LINE.................................................................................................................................12 TRAPS ............................................................................................................................................12 NETS ..............................................................................................................................................13 AQUACULTURE - SHELLFISH..........................................................................................................14 AQUACULTURE - FINFISH ..............................................................................................................15 2.2 THE POTENTIAL INTERACTIONS AND IMPACTS OF FISHING METHODS ON Natura 2000 HABITATS ..........................................................................................................................................16 SANDBANKS ..................................................................................................................................17 POSIDONIA BEDS...........................................................................................................................17 ESTUARIES.....................................................................................................................................18 MUDFLATS & SANDFLATS .............................................................................................................18 COASTAL LAGOONS.......................................................................................................................19 LARGE SHALLOW INLETS & BAYS ..................................................................................................19 REEFS.............................................................................................................................................20 BOREAL BALTIC NARROW INLETS .................................................................................................20 SUBMARINE STRUCTURES MADE BY LEAKING GASES ..................................................................20 SUBMERGED OR PARTIALLY SUBMERGED SEA CAVES..................................................................20 2.3 THE POTENTIAL INTERACTIONS AND IMPACTS OF FISHING METHODS ON Natura 2000 SPECIES ..........................................................................................................................................................21 CETACEANS ...................................................................................................................................23 SEALS.............................................................................................................................................23 TURTLES ........................................................................................................................................23 FISH ...............................................................................................................................................23 SEABIRDS, WADERS & WILDFOWL................................................................................................24 2.4 THE POTENTIAL VULNERABILITY OF Natura 2000 HABITATS AND SPECIES TO DIFFERENT FISHING METHODS............................................................................................................................24 2.5. THE POTENTIAL VULNERABILITY OF Natura 2000 HABITATS AND SPECIES TO RECREATIONAL FISHING METHODS............................................................................................................................32 CONCLUSIONS.......................................................................................................................................33 KEY REFERENCES ...................................................................................................................................34 GLOSSARY Sensitivity1; Sensitivity is dependent on the intolerance of a species or habitat to damage from an external factor and the time taken for its subsequent recovery. • 'Intolerance' is the susceptibility of a habitat, community or species (i.e. the components of a biotope) to damage, or death, from an external factor. Intolerance must be assessed relative to change in a specific factor. • 'Recoverability' is the ability of a habitat, community, or species (i.e. the components of a biotope) to return to a state close to that which existed before the activity or event caused change. Pressure; The mechanism through which an activity has an effect on any part of the ecosystem Vulnerability; A habitat, community or species becomes ‘vulnerable’ to adverse effects when it is both sensitive and exposed to an external factor (pressure). Vulnerability thus combines sensitivity and exposure to a pressure Exposure; The presence or likelihood of encountering the pressure/activity (temporally and/or spatially) FISHING GEARS DEFINITIONS2 Dredge; an apparatus usually in the form of an oblong iron frame with an attached bag net Dredge (hand); Small, light dredge, pulled behind by hand in shallow waters, from the shore or from a boat. Dredge (boat); dredge of varying weight and size, but usually fairly heavy, equipped with or within diving boards. Dredge (mechanised); Water jets dislodge molluscs from the seabed ahead of the dredge. The catch may be transferred to the boat by a conveyor belt device or by pump. Drift longline; Longline set in midwater or near surface and allowed to drift with the current. Drift net; drifting gillnet. Net kept on the surface, or at a certain distance below it by numerous floats. It drifts freely with the current, separately or, more often, with the boat to which the net is attached. Fish trap: trap; trap net; an inshore fishing apparatus consisting of a series of funnels, with their mouths kept open by hoops, opening into each other and finally closing into a sack forming a trap. This type of net, of which there are many variations, is fastened to the bottom Fixed net; General term for any simple net when it is held in fishing trim by anchors, sinkers and/or stakes Fyke net; Trap normally used in shallow water which consists of cylindrical or cone-shaped bags mounted on rings or other rigid structures, completely covered by netting and completed by wings or leaders which drive the fish towards the opening of the bags. Fyke nets, fixed on the bottom by anchors, ballast or stakes, may be used separately or in groups. Gill net; usually rectangular in shape, made of thin twine, which catches fish by holding them in the meshes, e.g. drift net, set gill net. Held vertically in the water by floats and weights. Gill net (fixed); net mounted on stakes driven into the bottom, used essentially in coastal waters. The fish are collected at low tide. Gill net (encircling); Gear generally used in shallow water with the floatline remaining at the surface. After the fish have been encircled by the net, noise or other means are used to force them to gill or entangle themselves in the netting surrounding them. Handline; a hand-held line with weighted end and hooks used to fish above the seabed 1 http://www.marlin.ac.uk/sensitivityrationale.php 2 CEC (1992) Multilingual Dictionary of Fishing Gear. 2nd Edition. Fishing News Books. EUR 14426. 333pp. Lampara net; the particular design of this net, with a central bunt in the form of a spoon and two lateral wings, makes it possible to retain the shoal of fish when the two wings are hauled up at the same time. Lampara nets are generally operated by a single boat, most often of small tonnage. Long line; a number of connected lines, either set at the bottom or drifting, each bearing a large number of baited hooks. Longline (bottom set): Long line set near the seabed. Net; fishing net; a fishing implement comprised mainly of netting. An open-work fabric forming meshes of suitable size for catching fish Otter twin trawl; gear comprising two identical trawl nets working together, opened horizontally by a single pair of otter boards. The inner wings are attached to a sledge towed simultaneously with the otter boards from a common crowfoot. Otter trawl (midwater); trawl towed by a single boat. The horizontal opening of the net is controlled by otter boards,