Danish Institute for Fisheries Research. Sea trout. Country report - Denmark Baltic Sea Trout Workshop in Kotka, 31. May 2.

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1 Danish Institute for Fisheries Research Sea trout Country report - Denmark Baltic Sea Trout Workshop in Kotka, 31. May 2. June 26

2 Danish part of the Baltic Populations of trout from outside the Baltic area are known to move south into the Baltic Jutland Funen Zealand 23 Sweden Bornholm 22 Germany Poland

3 Example from Karup Å Limfjord River Karup Kattegat North Sea Baltic Sea Kilometer

4 Recapture positions of trout tagged in Karup Å Symbols F1 F1_smolt Wild Events Hatchery Damsmolt Events Wild Vildsmolt Events Adults Havorred Events Kilometer

5 Official landings of sea trout Danish catches of sea trout in the Baltic Incl.rainbow trout Including catch by non-professionals

6 Official catches of sea trout Kg 6 8 Value (DKK) Baltic Total Denmark Value Baltic

7 Distribution of landed Baltic sea trout Kg Price (DKK)/Kg Landing Avg. price Bornholm Zealand Funen South Jutland East Jutland Other

8 Catch of sea trout in sports fishery

9 Catch of sea trout in sport fishery Sport fishery landings index 2,5 2 Number 1,5 1 Kolding ( =1) Horsens ( =1) Vejle ( =1),

10 Catch of sea trout in broodstock fishery

11 Catch of sea trout in broodstock fishery N Karup - Number / index of sea trout in broodstock-fishery Note sample only. Post fishing spawner abundance in approx. 9

12 Sea trout size distribution Karup - Length of sea trout in broodstock fishery

13 Regulations a few of them Minimum size 4 cm total length Mature and maturing seatrout closed season 16 Nov 15 Jan. Recreational fishery only for own use 5 m closed area around river mouths + many local regulations No nets -1 m from coast Stop nets (for otter) in fyke-nets Grids in entrances to fish-farms Upper edge of pound net below surface in spring

14 Regulations closed area Width of river > 2m: all year Width of river < 2 m: 16. Sep. 15. March

15 Regulations rivers + gear Entrance not in upstream direction March - May Recreational fishery only

16 Regulations recreational fishery

17 Regulations Case Simested å Dk kort gælder fra 1 aug 94 Permanent fra 98 Closed area extended from august 1994

18 Regulations - Case Simested å. 6 5 Number / index of sea trout Extended area closed for fishing Sea trout caugth by electric fishing

19 Regulations - Case Karup å. Fredning udvidet fra 1986 Fra 89 permanent Closed area extended June 1986

20 Size distribution of sea trout in broodstock fishery Karup Å Karup - Number / index of sea trout in broodstock-fishery N m line closed area all year from closed in winter months from

21 Stocking of fish Trout stockings in Denmark, (Thousands) Numbers Year Fry ½-yearlings Yearlings 2-years River Mouth Coast

22 Improvement measures habitat examples

23 Origin of sea trout - Baltic Total smolt production Wild River released as fry, ½ - and 1 year old River mouth rel.

24 Wild production by area Wild production Jutland Funen Zealand Bornholm

25 Origin - river releases by area Smolt from river releases of fry, ½- and 1 - year old Jutland Funen Zealand

26 Origin - river mouth releases by area River mouth releases Jutland Funen Zealand

27 Status of rivers by area Bornholm Zealand Good Satisf Poor Good Satisf Poor Funen Jutland Good Satisf Poor Good Satisf Poor

28 Monitoring of rivers in Baltic area Bornholm 18 streams 36 sites annually Zealand 253 streams 734 sites 7 year interval Funen 7 streams 411 sites 7 year interval Jutland 176 streams 16 sites 7 year interval Zealand, Funen and Jutland: additional monitoring by counties and municipalities

29 Threats Flow lack of habitat Eastern part (Bornholm, Zealand) Bird predation All areas (heron) western part (heron, cormorant) Habitat quality Western part: silting of spawning grounds, modification of habitats, maintenance of streams

30 Threats Illegal fishing All areas recently proven in Jutland and Funen Access to spawning grounds Diminishing - mostly western part (Jutland) Downstream passage Fish farms, water mills, lakes mostly western part (Jutland)

31 Outcome of releases - taggings

32 Outcome of releases - Gudenå River and river related releases Recapture % Fjord River Mouth River Upper River

33 Outcome of releases various rivers Various rivers Recapture %

34 Outcome of releases sea releases Various sea releases Rec %

35 Research present and recent areas of work Habitats Origin (wild vs hatchery) - Genetics Negotiation of: Weirs Fjords Predators

36 Needs for research Index river: smolt production of stocked and wild trout Spawning escapement Model for sea- and freshwater survival Sea trout biology in the sea (black/grey box) Modelling habitat quality (possibly by RHYHABSIM) Habitat work: natural and regulated rivers; rivers with differing discharge pattern Development of methods to tag small fish Exchange of experience in restoring populations and habitats in rivers Exchange of research knowledge / methods

37 Danish Institute for Fisheries Research