Hi Kim,

there are some examples from Florida recreational fisheries. These are some examples: Black Drum, Snook, Red Drum, Permit, Spotted Seatrout. (see pdf here: http://www.sebastianinletdistrict.com/pdf/2014FWCRegulations.pdf)

Best regards,

Alex

Fisheries on White Sturgeon in the Columbia River are managed on a slot size restriction to allow juveniles to reach a desirable size and to protect older fish once they become capable of reproduction. Examples from Washington State fishing regulations below (http://wdfw.wa.gov/publications/01818/wdfw01818.pdf). Also have seasonal closures for retention that are set to avoid spawning timing in some cases.

Below Bonneville Dam - no size restriction

STURGEON May 1-Aug. 31: CLOSED to fishing for STURGEON from Bonneville Dam downstream 9 miles to a line crossing the Columbia from Navigation Marker 82 on the Oregon shore westerly to the boundary marker on the Washington shore upstream of Fir Point. STURGEON fishing is CLOSED on the Washington mainland shore from Bonneville Dam downstream to a boundary marker about 4,000' downstream from the fish ladder at the new Bonneville Dam Powerhouse south to the downstream end of Cascade Island and across to the Oregon angling boundary on Bradford Island (about 850' downstream from fish ladder). From Bonneville Dam to a line from the Hamilton Island boat ramp to an Oregon boundary marker on Robins Island: 1) it is unlawful to fish for STURGEON except with hand-casted lines from shore; 2) it is also unlawful to use a floating device to set lines for STURGEON.

From Bonneville Dam to The Dalles Dam

STURGEON Jan. 1 opens to retention, and closes when the winter quota is met (refer to the WDFW website wdfw.wa.gov). Min. size 38" fork length. Max. size 54" fork length. Daily limit 1.

Catch-and-release allowed when closed to retention. Check the WDFW website

wdfw.wa.gov for 2016 and 2017 summer STURGEON retention seasons.

From The Dalles Dam to McNary Dam

STURGEON May 1-July 31: CLOSED to fishing for STURGEON from John Day Dam downstream 2.4 miles to the west end of the grain silo at Rufus, Oregon. May 1-July 31: CLOSED to fishing for STURGEON from McNary Dam downstream 1.5 miles to Hwy. 82 (Hwy. 395) Bridge.

STURGEON Jan. 1 opens to retention, and closes when annual quotas are met (refer to the WDFW website wdfw.wa.gov). Min. size 43" fork length. Max. size 54" fork length. Daily limit 1. Catch-and-release allowed when closed to retention.

from McNary Dam to Priest Rapids Dam

STURGEON Feb. 1-July 31 Min. size 43" fork length. Max. size 54" fork length. Daily limit 1.

STURGEON Aug. 1-Jan. 31 Catch-and-release. to use a floating device to set lines for STURGEON. STURGEON Year-round Catch-and-release.

Above Priest Rapids Dam

Catch and release only

E.g., the recreational fishery for halibut in Canada (British Columbia): The maximum overall length for halibut is 133 cm. http://notices.dfo-mpo.gc.ca/fns-sap/index-eng.cfm?pg=view_notice&DOC_ID=193452&ID=all

Thank you very much, Alexandre, Steven and Vladimir  - these were all new examples to me. Attached is a recent publication on the effects of harvet slot limits on pike-populations in Finland.

Best,

Kim

good project.

Please refer ICLARM.

Many angling clubs in Germany manage predatory fish now with harbvest slots. Also, the fishing law of Hamburg recently replaced minimum length with harvest slots, mainly thinking of zander.

Argyrosomus japonicus in South Africa and Argysosomus inodorus in Namibia are semi slot regulated. There is a limit of five Argyrosumus spp individuals per day in certain areas of South Africa, but only one over 1100 cm TL. (see attached brochure). This is due to species mis-identification between A. japonicus and A. inodorus with A. japonicus maturing at larger sizes and being of higher conservation concern. Similarly in Namibia there is confusion between A. inodorus and A. coronus with the later species attaining a larger size, their limit is 10 Argyrosomus spp per day over 40 cm TL, but only two over 70 cm TL. The Namibian regulation was not intended to protect A. coronus but rather protect larger spawning A. inodorus stock (declared about 20 years ago). A. coronus has only recently entered the Namibian fishery due to southerly distributional shifts but marginally benefits from this maximum size limit given that it matures at a size > 100 cm TL.

Pacific halibut ( Hippoglossus stenolepis ) is managed by harvest slots in Alaska.

Many species for example in the US state of Florida such as red drum (Sciaenops ocellatus), snook (Centropomus undecimalis), speckled trout (Cynoscion nebulosus), Barracuda (Sphyraena barracuda) or permit (Trachinotus falcatus) are managed with a harvest slot.

The slots can vary from year to year according to results from recruitment monitoring.

See: https://myfwc.com/media/20441/quickchart.pdf

Ilegal fishing has a significant role to decrease the commercial fish population.

Wisconsin has managed walleye and black bass with no harvest slot limits for some time. We're also testing a Max length limit on smallmouth bass to improve size structure right now.

In Pakistan slot harvest is also being managed by mesh size of fishing nets during fish catching operations in freshwater catches. Close seasons are also being observed for protection of species by imposing complete ban on certain fish species catches during breeding seasons. however other environmental issues such as pollution, water flows, displacements etc. are affecting the fish compositions & population more severely.

Hi Kim

Our department recently reviewed current size limits in Western Australia. This report might be useful to you http://www.fish.wa.gov.au/Documents/management_papers/fmp280.pdf

One example - a maximum size limit for a large epinephelid was proposed to be removed, as such fish are often susceptible to post-release mortality (e.g. from barotrauma). The size limit essentially defeated its own purpose!

Pike in Ireland are managed with a maximum size limit of 50cm: http://www.fishinginireland.info/regulations.htm. The intention is to protect Big Fat Fecund Female Fish (BOFFS), as almost all of the largest individuals are female. This regulation has caused considerable controversy among anglers, due to the belief that these large fish may prey heavily on wild brown trout. Recent evidence suggests that invasive non-native roach are actually the dominant prey Article Shifts in diet of an apex predator following the colonisatio...

Harvesting size should be agreed with experts in order to regulate the time and the net type to control the fishing.

From an invertebrate perspective...

West US coast Dungeness (Metacarcinus magister) and rock crab (Cancer productus) are managed via minimum size with females being illegal to possess. On the east coast, jonah crab (Cancer borealis have just been changed in the past few years to minimum size. The most valuable fishery in the US, American lobster (Homarus americanus) in almost all US waters is managed with a slot limit (with special rules designed to protect egg-bearing females). As I understand it, across the border in Canada, there is only a minimum legal size for lobster.

Fish stock should be manged by fishing regulation and protect nursery ground from pollution and illigal fishing.

At least naturally occurring brown trout over 45 cm in Finland should be released if caught in a pond or stream without migration connection to a lake or the sea. https://www.eraluvat.fi/en/fishing/fisheries-management/minimum-catch-sizes-and-protection-periods.html

Regulation should be issued to protect fish from illegal fishing and pollution.

European Lobster (Homarus gammarus) fisheries are managed using slot fisheries in both the Republic of Ireland (ROI)and Scotland (SCO). The ROI operates a min of 87mm to max of 127mm carapace length. SCO operates a minmum of 87/90mm-145mm carapace length across the mainland and the western isles. The slot fishery changes in the northern isles (orkney & Shetland) with a minimum of 90mm and maximum of 156mm. The implementation of the slot sizes in both ROI and SCO hinges on technical measures being the primary method of fishery regulation, with limited regulation in most cases on input controls such as effort. In the case of the slot fishery in orkney and known biological information the maximum size is too large to convey any additional benefit to the current minimum landings size in regards to egg per recruit modelling https://www.researchgate.net/publication/332080099_Components_of_Individual_spawning_potential_of_European_lobster_Homarus_gammarus_L_in_Orkney_Scotland

Hi Kim, in 2014 the Victorian State Government (Australia) introduced a slot limit to meet conservation and fishery objectives for our iconic large freshwater fish species, the Murray cod. I have attached a discussion paper and video (https://www.youtube.com/watch?v=t3QJ4X1uBXA) we used to help communicate the proposed change to recreational fishers. Hope this helps, Cheers, Taylor