Pink shrimp (Pandalus jordani) in the USA exclusive economic zone excl. Alaska, Demersal otter trawl

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1 Pink shrimp (Pandalus jordani) in the USA exclusive economic zone excl. Alaska, Demersal otter trawl Content last updated 19th Oct 2015 Pink shrimp (Pandalus jordani) in the USA exclusive economic zone excl. Alaska, Demersal otter trawl Stock: Pink shrimp (Pandalus jordani) in the USA exclusive economic zone excl. Alaska Management: Pacific Fisheries Management Council and the National Marine Fisheries Service, USA Overview Pink shrimp (Pandalus jordani) are found in waters from southeast Alaska to California at depths of 37 to 460 meters. High densities of pink shrimp occur in well-defined areas, known as shrimp beds, over green mud or mud-sand substrates. As a protandric hermaphrodite, pink shrimp typically mature first as a male but change sex at an age of around 1 to 2 years old and complete the remainder of their live cycle as a female. Females usually begin to reproduce at two years of age in September and October, and the peak hatching period occurs during late March and early April. Some females may survive to repeat the mating process in succeeding years. Natural mortality is most pronounced immediately following hatching, and most pink shrimp do not live past 4 years of age. Newly hatched shrimp spend two to three months as pelagic larvae, and developing juveniles occupy successively deeper depths as they grow. This species undergoes diel vertical migration by inhabiting deeper waters near the seabed during the day and ascending in the water column during the night to feed. They feed on smaller planktonic animals, such as euphausiids and copepods; and they are mainly preyed on by finfish, sea birds and marine mammals. This species can reach a maximum total length of 14 cm (Devitt et al., 2007). Catches of pink shrimp in the USA exclusive economic zone (California to Washington) reached a record high of around tons in Pink shrimp are taken in a demersal otter trawl fishery for mixed shrimp species off the West Coast of the USA that mainly operates in Washington, Oregon and northern California. Most catches of pink shrimp are taken in Oregon with around sixty licenced vessels participating in the fishery. Vessels operating in the fishery are typically less than 100 feet in length and use a double rigged system of box trawls fitted with mandatory bycatch reduction devices. The fishing season runs from the 1 st of April to the 31 st of October, and most commercial catches are taken in the daytime at depths between 90 and 180 meters. The fishery targets pink shrimp between one and two years of age and is strongly influenced by fluctuations in recruitment. No formal assessment has been conducted and no reference points for long-sustainability have been defined for this data-limited stock. Management of this stock is by technical measures and no Total Allowable Catch (TAC) has been allocated (Devitt et al., 2007; Fisheries of United States, 2014; Hannah and Jones, 2015). Devitt, S., Parsons, D., Pedersen, M. and Wilen, J The Oregon Pink (Ocean) shrimp trawl fishery. Public certification report. Contract Number: Oregon Ocean Shrimp. Version: Final Report Version pp. Fisheries of the United States Current Fishery Statistics No National Marine Fisheries Service Office of Science and Technology, pp. Hannah, R. W. and Jones, S th Annual Pink Shrimp Review. Newport, OR: Oregon Department of Fish and Wildlife. 12 pp. Stock Status less risk more risk The status of the pink shrimpstock in the USA exclusive economic zone (California to Washington) has been scored a low risk. This is because the species has a relatively low maximum vulnerability score of 34/100 (Townsend, 2014) and the most recent review indicates that the proxy for stock abundance has increased since No formal stock assessment is undertaken for this data-limited species. The low vulnerability score epitomises the robust life history characteristics of this species which makes it resilient to fishing activities (e.g. early maturation (<5 years), short life cycle (< 10 years), small maximum size and low on the food chain), and corresponds to the FishBase/SeaLifeBase vulnerability score that ranges between 0 and 35 (Townsend, 2014). A risk score was derived for this stock by assuming a worst case scenario and selecting a maximum vulnerability score of 34/100 weighted by the increasing population trend. Management less risk more risk The management of pink shrimp in the USA exclusive economic zone (California to Washington) has been scored a very low risk. This is because management decisions are informed by an annual stock review based on commercial catch data, a comprehensive regulatory framework has been established and controls adequately protect the stock from overexploitation. Regulations are enforced and independently verified using several surveillance measures. Bycatch less risk more risk The bycatch impact of the demersal otter trawl fishery for pink shrimp in the USA exclusive economic zone (California to Washington) has been scored a moderate risk. This is because bycatch in the demersal otter trawl fleet is estimated to be low (maximum of <6% of total catch weight) and all vessels in the fishery have taken steps to reduce bycatch levels using bycatch reduction devices. A substantial research effort has focused on developing bycatch reduction devices, such as, fitting artificial (LED) lights on demersal otter trawls to reduce groundfish bycatch. Habitat less risk more risk The habitat impact of the demersal otter trawl fishery for pink shrimp in the USA exclusive economic zone (California to Washington) has been scored a moderate risk. Although demersal otter trawls interact with the seabed, all vessels in the fishery have taken steps to reduce their habitat impact by using appropriate gear

2 technology and 51 discrete areas have been closed to trawling to protect vulnerable marine habitats. Outlook Current risk status Outlook Reason Stock Low Improving The status of the stock is likely to improve in the future given that this species has a low maximum vulnerability score of 34/100 and the most recent review indicates that the proxy for stock abundance has increased since Management Very low Stable The management of this stock is likely to remain stable in the future given that the stock review is updated annually and control measures are in place to adequately protect the stock from overexploitation. Regulations are enforced and independently verified using several surveillance measures. Bycatch Moderate Stable The bycatch impact of the fishery is likely to remain stable in the future. Bycatch levels in this fishery are low (maximum of <6% of total catch weight) and all vessels have taken steps to reduce the absolute quantity of bycatch using bycatch reduction devices. Gear modifications are continuously under development to further reduce bycatch levels. Habitat Moderate Stable The habitat impact of the fishery is likely to remain stable in the future. All vessels in the fishery have taken steps to reduce the footprint of the gear on the seabed by using appropriate gear technology and 51 discrete areas have been closed to trawling to protect vulnerable marine habitats in the region. Type Current Risk Status Outlook Reason Stock Management Bycatch Habitat

3 Stock Status Details less risk more risk Time-trends A demersal otter trawl fishery for pink shrimp has been in operation in Oregon, California and Washington since Landings have been highly variable over time, characterised by distinct peaks and troughs due to recruitment fluctuations (Figure 1). Pink shrimp landings steadily increased from a low in 1957 to reach a peak in 1978, and then decreased sharply until Similar peaks and troughs occurred throughout the 1990s and 2000s. Most landings of pink shrimp (66%) originate from waters off Oregon. Annual landings in Oregon ranged from around tons during periods of high biomass to tons when shrimp abundance is low (Hannah and Jones, 2015). Landings varied from to tons in Washington between 2007 and In California, landings ranged from 290 to tons between 2007 and Total annual landings from the three states combined increased from tons for the period to tons for the period Pink shrimp landings reached a record high of around tons in 2014 (Fisheries of United States, 2014). Commercial catch per unit effort (CPUE) fluctuated around average between 1968 and 1978, followed by periods of oscillation throughout the 1980s, 1990s and early 2000s (Figure 2). CPUE has increased since 2005, reaching the highest levels on record from 2009 onwards. The increase in CPUE indicates that stock abundance has increased to a record high over the last decade. Consequently, the stock has been harvested sustainably and remains highly resilient to fishing activities and natural disturbance events. Figure 1. Oregon pink shrimp landings (millions of pounds) Includes all pink shrimp landed into Oregon ports (Hannah and Jones, 2015). Figure 2. Catch per unit of effort (CPUE = lbs/sre hour) for vessels landing pink shrimp into Stock structure and recruitment Oregon between 1968 and 2014 (Hannah and Jones, 2015). For assessment and management purposes, the pink shrimp population inhabiting the USA exclusive economic zone (California to Washington) is considered by the Department of Fish and Wildlife to be a single stock. No genetically distinct sub-populations of pink shrimp have been identified off the coasts of California, Oregon, Washington and British Columbia (Collier and Hannah, 2001). Adults from different shrimp beds rarely intermix, but the planktonic larvae undoubtedly intermingle given the lack of genetically distinct sub-populations in the region. Pink shrimp recruitment is highly variable over time and strongly influenced by environmental conditions within a particular fishing area. Strong year-classes were evident in 1984, 1999 and An exceptionally large recruitment event in 2013 resulted in an increase in landings in 2014 (Hannah and Jones, 2014; 2015). Data gaps and research priorities For this stock, the main research priority is to continue examining shrimp population dynamics. Commercial fisheries data should be used to estimate total catch-at-age and effort by area. In addition, a re-evaluation of the fishery s long-term effects on shrimp population structure should be completed. More information on how recent increases in shrimp density have influenced growth rates, age composition and sex change ratios is required (Hannah and Jones, 2015). Research focusing on the use of artificial (LED) lights on trawls to reduce finfish bycatch should be ongoing. Feedback from fishers on how the lights are best installed, maintained and utilised is required (Hannah and Jones, 2015). A better understanding of the effects of the demersal otter trawl fishery on the ecosystem is needed. A camera system should be developed to improve knowledge of the ecosystem effects of fishing (Hannah and Jones, 2015). Collier, P.C. and Hannah, R.W Ocean shrimp. In: California s living marine resources: a status report. California Department of Fish and Game, pp Fisheries of the United States Current Fishery Statistics No National Marine Fisheries Service Office of Science and Technology, pp. Hannah, R.W. andjones, S.A Effects of climate and fishing on recruitment of ocean shrimp (Pandalus jordani): an update of recruitment models through Fish Division. Oregon Department of Fish and Wildlife. Information Reports: pp. Hannah, R. W. and Jones, S th Annual Pink Shrimp Review. Newport, OR: Oregon Department of Fish and Wildlife. 12 pp. Townsend S., Coonstripe shrimp, Dock shrimp, Pink shrimp, Northern shrimp, Sidestripe shrimp, Spot prawn, Ridgeback shrimp. Pandalus hypsinotus, Pandalus danae, Pandalus jordani, Pandalus borealis, Pandalus dispar, Pandalus platyceros, Sicyonia ingentis. Alaska, California, Washington, Bottom Trawl, Trap. Monterey Bay Aquarium, Seafood Watch Report. 77 pp.

4 Management Details less risk more risk Monitoring Pink shrimp in the USA exclusive economic zone (California to Washington) is reviewed annually by the Department of Fish and Wildlife/Game in each respective state (Oregon, California and Washington) to estimate commercial catch-at-age, fishing effort, market prices and recruitment. The stock assessment is based on a time-series of commercial catches including sex and size compositions as well as an index of recruitment derived from commercial catch rates. A formal stock assessment has not been undertaken and the annual stock review is based on fishery-dependent data. No reference points for long-term sustainability have been defined for this data-limited stock (Hannah and Jones, 2014; 2015). Standardised research surveys were undertaken in California in the early-1980s to obtain fishery-independent data. However, the research surveys were expensive to undertake and ran into a number of operational problems. Extreme variability in shrimp catches, some of which was attributed to the vertical distribution of the species, limited the usefulness of abundance/biomass estimates from the surveys (Devitt et al., 2007; Frimodig et al., 2009; Hannah and Jones, 2015). Control The fisheries for pink shrimp in the USA exclusive economic zone (California to Washington) are managed by the Pacific Fisheries Management Council (PFMC) and the National Marine Fisheries Service (NMFS) primarily through technical measures set to achieve long-term sustainability targets (Magnuson-Stevens Act, 1996). A draft management plan for pink shrimp in waters off California, Oregon, and Washington was developed by the PFMC in 1981, but not formally adopted. In 2004, management authority over the California fishery was granted to the Fish and Game Commission. Pink shrimp are mainly taken in a demersal otter trawl fishery for mixed shrimp species that operates on the west coast of the USA. The current review indicates that controls have been effective in increasing stock abundance since No annual total allowable catch has been set for this data-limited stock (Hannah and Jones, 2015). Major harvest control measures for pink shrimp in the USA exclusive economic zone (California to Washington) include mandatory commercial fishing vessel licensing, a limited entry shrimp fishing permitting system (currently 138 permits), a 7-month fishing season, a closed fishing season which avoids the reproductive period of the shrimp stock, a minimum catch rate of 350 pounds-per-hour to protect shrimp when the population was at a low level and a maximum shrimp count per pound (<160) to control of average shrimp size in catches. No trawling is allowed within California state waters (0-3 miles) (Devitt et al., 2007; Frimodig et al., 2009; Hannah and Jones, 2015). Harvesting of pink shrimp in the USA exclusive economic zone (California to Washington) is also controlled through gear restrictions. Demersal otter trawls are only permitted to operate in the fishery with a minimum mesh size of 1-3/8 to decrease catches of undersized shrimp. In addition, the use of groundfish bycatch reduction devices such as a Nordmøre separator grate, a soft-panel excluder and a fisheye excluder has been mandatory since In 2015, the NFMS proposed the following groundfish limits: a groundfish trip limit of 1500 lb/trip that does not exceed 500 lb/day; the weight of groundfish landed may not exceed the weight of shrimp landed; Canary Rockfish, Thornyheads and Yelloweye Rockfish are prohibited species; a 300 lb/month lingcod catch limit with a minimum landings size of 24, Sablefish; a 2000 lb/month sablefish catch limit, limited entry groundfish vessels possessing pink shrimp permits and harvesting pink shrimp must stay within the daily/monthly limits established for the shrimp fishery and include any fish catch taken while shrimping toward their species limits for the limited entry groundfish fishery (Devitt et al., 2007; Frimodig et al., 2009; Hannah and Jones, 2015). The PFMC has designated several Essential Fish Habitat (EFH) areas off the Oregon coast as no-trawl zones. The areas are set aside to protect vulnerable marine habitats. Shrimpers are cautioned not to trawl within these areas (Hannah and Jones, 2015). Surveillance Fisheries on pink shrimp inthe USA exclusive economic zone (California to Washington)are carried out by the USA and surveillance activities to record compliance with national fishery control measures are primarily the responsibility of the states of Oregon, California and Washington. Surveillance activities on fisheries for pink shrimp inthe USA exclusive economic zone (California to Washington)include the use of electronic vessel monitoring systems (VMS) on each vessel; direct observation by patrol vessels and aerial patrols; inspections of vessels, gear, catches at sea and onshore; daily reporting of position and catch and submission of vessel fishing log books; verification of logbook data against sales documents; electronic databases containing the inspection and surveillance reports of their officials as well as records of infringements. Vessels must declare before leaving for their first shrimp trip of the season and file a declaration report before fishing in any Rockfish Conservation Area (RCA). Compliance with rules is monitored mainly onshore by the State Police, by the State staff responsible for fisheries management (e.g. the Oregon Department of Fish and Wildlife) and by fish processing plants. A federally sponsored at-sea observer program (WCGOP) was implemented in in the pink shrimp fishery in 2002 (Devitt et al., 2007; Hannah and Jones, 2015). Devitt, S., Parsons, D., Pedersen, M. and Wilen, J The Oregon Pink (Ocean) shrimp trawl fishery. Public certification report. Contract Number: Oregon Ocean Shrimp. Version: Final Report Version pp. Frimodig, A.J., Horeczko, M.C., Prall, M.W., Mason, T.J., Owens, B.C. and Wertz, S.P Review of the California trawl fishery for Pacific Ocean Shrimp, Pandalus jordani, from 1992 to Marine Fisheries Review 71: Hannah, R. W. and Jones, S The population dynamics of Oregon Ocean Shrimp (Pandalus jordani) and recommendations for management using target and limit reference points or suitable proxies. Fish division. Oregon Department of Fish and Wildlife. Information Reports: , 24 pp. Hannah, R. W. and Jones, S th Annual Pink Shrimp Review. Newport, OR: Oregon Department of Fish and Wildlife. 12 pp.

5 Bycatch Details less risk more risk Targeting and behaviour Demersal otter trawls that catch pink shrimp in the USA exclusive economic zone (California to Washington)are towed by a single boat as a single or multiple rig. In this region, demersal otter trawls must have a minimum mesh size of 1-3/8 to decrease catches of undersized shrimp and be fitted with mandatory groundfish bycatch reduction devices. Nordmøre separator grates minimise groundfish bycatch by directing groundfish upwards towards an exit window in the upper panel while shrimp pass through the grate and are retained in the catch. Other established groundfish bycatch reduction devices include soft-panel excluders and fisheye excluders. A substantial research effort has focused on modifying trawl gear to reduce bycatch levels. For example, fitting artificial (LED) lights to otter trawls has been found to be an effective method of reducing groundfish bycatch in recent trials (Hannah and Jones, 2015). Otter trawls can be rigged with different types of ground gear depending on seabed topography and the species targeted (Løkkeborg, 2005). When targeting pink shrimp, ground gear such as bobbins or rubber discs are fitted to the ground rope to enable operation on rougher seabed types. The ground gear is linked to the leading lower edge of the net by vertical toggle chains. The use of the chains is intended to allow the trawl to be towed clear of the bottom to minimise seabed contact and further reduce groundfish bycatch. Evidence of bycatch levels in the demersal otter trawl fishery for pink shrimp in the USA exclusive economic zone (California to Washington) Bycatch of non-target species has been drastically reduced in the demersal otter trawl fishery since the mandatory implementation of bycatch reduction devices in Discards were estimated to be less than 1% of total catch weight between 2007 and 2010 in Oregon (Parsons et al., 2013). Total discards were estimated to be less than 6% of total catch weight between 2008 and 2011 in California (Anon., 2013). No quantitative information on discards was available for the fishery operating off Washington. Bycatch levels are monitored by the North Pacific Groundfish and Halibut Fisheries Observer Program. Most of the discards in the demersal otter trawl fishery were comprised of other shrimp species. Nevertheless, bycatches of finfish can occasionally occur with Pacific hake (Merluccius productus), slender sole (Lyopsetta exilis) and rex sole (Errex zachirusb) most frequently discarded. The average bycatch level is dependent on the bar spacing of the bycatch reduction device and ranges between 1 and 6% of the total catch weight. The demersal otter trawl fishery in the USA exclusive economic zone has the lowest discard rate among world shrimp fisheries (Frimodig, 2008). Mitigation measures Bycatch reduction devices were introduced into the demersal otter trawl fishery operating off the west coast of the USA in 2000 to reduce bycatch levels. The use of a Nordmore separator grate onboard demersal otter trawls with specified bar spacing of 32 mm is mandatory. Other bycatch reduction devices used in the fishery include soft-panel excluders and fisheye excluders. Limits have been imposed on bycatches levels of non-target species and landing some species has been prohibited. A minimum mesh size of 1-3/8 has been established in the demersal otter trawl fishery to control bycatch of small non-target shrimp (Hannah and Jones, 2015). Research focusing on gear modifications to reduce finfish bycatch is ongoing. For example, fitting artificial (LED) lights onto otter trawls has proven effective in reducing bycatches of eulachon smelt (Thaleichthes pacificus), which remains listed as threatened under the Endangered Species Act (Hannah and Jones, 2015). In 2015, the NFMS proposed the following groundfish limits: a groundfish trip limit of 1500 lb/trip that does not exceed 500 lb/day; the weight of groundfish landed may not exceed the weight of shrimp landed; Canary Rockfish, Thornyheads and Yelloweye Rockfish are prohibited species; a 300 lb/month lingcod catch limit with a minimum landings size of 24, Sablefish; a 2000 lb/month sablefish catch limit, limited entry groundfish vessels possessing pink shrimp permits and harvesting pink shrimp must stay within the daily/monthly limits established for the shrimp fishery and include any fish catch taken while shrimping toward their species limits for the limited entry groundfish fishery (Hannah and Jones, 2015). Anon Frimodig, A Informational report: Bycatch Reduction Devices used in the pink shrimp trawl fishery. Report to the California Fish and Game Commission. California Department of Fish and Game, Marine Region, State Fisheries Evaluation Project. 12 pp. Hannah, R. W., Jones, S th Annual Pink Shrimp Review. Newport, OR: Oregon Department of Fish and Wildlife. 12 pp. Løkkeborg, S Impacts of trawling and scallop dredging on benthic habitats and communities. FAO Fisheries Technical Paper 472. Food and Agriculture Organisation of the United Nations,Rome, 58 pp. Parsons, D., Pedersen, M., Hanna, S. and Park, A The final report and determination of the Oregon Pink Shrimp (Pandalus jordani) Trawl Fishery, 226 pp.

6 Habitat Details less risk more risk Demersal otter trawls can impact seabed habitat by modifying bottom topography and disturbing biogenic features. Trawl doors have the most pronounced impacts on seabed habitats by creating scouring marks and furrows up to 20 cm deep (Løkkeborg, 2005). Otter trawling has been shown to modify macroinvertebrate abundance and diversity in this region. Densities of sea whips (Halipteris spp.), corals and invertebrates are lower at heavily trawled sites. Nevertheless, more extensive and repeated visual surveys of areas with different levels of historical trawling are needed to further clarify the impact of trawls on seabed habitat and the potential for ecosystem recovery (Hannah et al., 2009; 2014). Mitigation measures The Pacific Fishery Management Council closed 51 discrete areas on the U.S. west coast to demersal otter trawling in June 2006 to protect vulnerable marine habitats (Hannah et al., 2014). Two types of closures have been established in the region: areas where demersal otter trawling is prohibited and areas where all bottom-contacting gears are prohibited. The areas are seasonally fixed and not modified by inseason or biennial changes in management actions (NOAA, 2015). Hannah, R.W., Jones, S.A., Miller, W., Knight, J.S Effects of trawling for ocean shrimp (Pandalus jordani) on macroinvertebrate abundance and diversity at four sites near Nehalem Bank, Oregon. Fishery Bulletin, 108: Hannah, R.W., Jones, S.A., Kupillas, S., Miller, W A comparison of 2007 and 2013 macroinvertebrate surveys of mud habitats at Nehalem Bank, Oregon: changes in areas with continued trawling and those closed to trawling in Fish division. Oregon Department of Fish and Wildlife. Information Reports: , 30 pp. Løkkeborg, S Impacts of trawling and scallop dredging on benthic habitats and communities. FAO Fisheries Technical Paper 472. Food and Agriculture Organisation of the United Nations,Rome, 58 pp. NOAA Small entity compliance guide: Pacific coast groundfish essential fish habitat conservation area closures and gear prohibitions. Available at: All content 2018 Seafish. Origin Way, Europarc, Grimsby, DN37 9TZ. This page created on 17th August 2018 at 09:43pm.