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Comprehensive overview of commercial & recreational blue crab fishing in New Jersey, including harvest trends, licensing, and survey data. The survey aims to estimate fishing effort, harvest, and gear usage in the state's portion of Delaware Bay.
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Survey of New Jersey’s Recreational Blue Crab Fishery in Delaware Bay By Brandon W. Muffley* New Jersey Division of Fish & Wildlife Marine Fisheries Administration & Lynette Lurig New Jersey Division of Science, Research and Technology
New Jersey’s Blue Crab Fisheries Commercial Fishery (State Wide): • 5.37 million pounds – 10 year average harvest (97-06) • 2002 highest with 6.41 million pounds • 2003 lowest with 4.1 million pounds • $ 5.7 million dockside economic value • Type of fishery: • Crab Pot and Dredge fisheries Pot Fishery – 87%, Dredge Fishery 13% • 1995 all crab fisheries became limited entry • Pot limits (DE Bay – 600; Coast – 400) • 643 commercial crab licenses issued – 5 year average * Licenses not necessarily indicative of participation * Many (nearly half) of all licenses are not active
NJ’s Commercial Fishery in DE Bay • Total crab harvest (hard and peeler) has averaged 3.1 million pounds (10 year) • Crab Pot harvest has averaged 2.9 million lbs with no trend • Crab Dredge harvest has averaged 148,000 lbs and has increased • Overall, DE Bay accounts for approx. 58% of NJ’s total crab harvest • DE Bay accounts for 63% of the total Crab Pot harvest • DE Bay accounts for 21% of the Dredge harvest • Average ‘active’ licensees in DE Bay fishery - 156 - 112 pots, 44 dredge • Only 58% of the licenses are active
Recreational Fishery Background • Recreational crabbing occurs in all of NJ’s estuaries • (DE Bay, Coastal bays, Sandy Hook and Raritan Bay) • Recreational harvest is believed to equal or • exceed commercial harvest • Series of surveys conducted in the 1970’s concluded: • More effort expended in catching crabs than any other species • 75% of the states residents took at least one crabbing trip • Average harvest was 6 – 12 crabs each • Information only on residents - non-residents make up a substantial • portion of the effort, particularly in summer months in coastal bays • Numerous recreational crabbing techniques: commercial style pots, • collapsible traps, baited/hand lines and dip nets and • more!!
Recreational Fishery Cont. NJ’s Recreational Blue Crab Fishery Data Collection (or lack there of): *Recreational Crab Pot License: - Initiated in 1985 - Allows one to set 2 commercial style pots per license - Various seasonal and area closures - Often used without a license – especially by summer visitors - Possible measure of effort * No licenses required for any other gear type (some exceptions) * No other data is collected or has been collected since the surveys from the 1970’s
Why This Survey? Developed a comprehensive state-wide blue crab monitoring/assessment program including commercial, recreational, fishery independent aspects (under unlimited resources – in terms of funding and staff) – What would give us the biggest bang: Influencing Factors: One year or short term funding Evidence/perception of its importance and impact No reliable or recent estimates – no data collected since 70’s! Immediate application to DE Bay joint (DE/NJ) stock assessment Have other blue crab data collected from region – trawl survey
Survey Goals/Objectives Overall Goal: Initiate the first-ever statewide monitoring program to sample NJ’s recreational blue crab fishery Specific 2005 Survey Objectives: 1. Estimate the monthly fishing effort and harvest by gear within NJ’s portion of DE Bay 2. Characterize the size and sex structure of the recreational harvest 3. Use the 2005 results to improve/modify future sampling program surveys Accomplished through a randomized sampling methodology collected by Telephone and Dockside Intercept Interviews focusing only on the recreational blue crab fishery (similar to the MRFSS survey for finfish species)
Courtesy of ORC Macro Survey Design - Telephone • 1. Target Area – Tri county area of Salem, Cumberland and Cape May • - considered residents for this survey (other NJ counties considered non-residents) • - most cost effective – more targeted calls • 2. Fielding Period – June through November – asked about previous month of activity • Data Collected - # of Recreational Crabbers, # of Trips/Month, Harvest/Month, • Gear Type and Access location • Population Covered – Telephone households – crabbing and non-crabbing • Population Not Covered – Non-telephone households and non-resident crabbers • 6. Stratification – County population and • Monthly • 7. Assignments – Mix of day and evening, • Weekend and Weekday
Courtesy of ORC Macro Telephone Survey continued • Data obtained from the Telephone portion of the survey is used to estimate • Total # of Recreational Crabbing Trips by Tri-County Residents • Completed Interview Target – 2,250 Interviews (allocated regionally and seasonally) • * 2,273 actual completed interviews • * Nearly 16,000 calls were attempted to reach the Target • * Of the completed calls – 103, 4.5%, were positive calls (i.e. crabber interviewed) • Collapsed Response Categories: • * Ideally would obtain effort by each gear type for each location, during each • month and for each county – but limited by sample size • * Collapsed Categories are the smallest sub-unit used to • classify crabbing activity • Gear Type– Crab Pot, Collapsible Trap, All Others • Mode – Land (Pier, Jetty, Bank, Beach etc.), • Boat (Private, Rental) • Season – Early (May-June), Peak (July-Aug), • Late (Sep-Oct) • County – Salem, Cumberland, Cape May • and Tri-County
Courtesy of ORC Macro Survey Design – Intercept • Target Area – Tri county area of Salem, Cumberland • and Cape May • 2. Fielding Period – May through October • Data Collected – # of Crabs caught/harvested, • Biological (count, size, sex), # of Trips, • Gear Type, Residency and Telephone Status • 4. Population Covered – Recreational Crabbers visiting predetermined sites • 5. Population Not Covered – Recreational Crabbers visiting sites not on list • Stratification – Expected Activity, Day Type (weekday/weekend), and Monthly • 7. Assignments – Allocated to Weekdays and Weekends
Intercept Survey Cont. • Data obtained from the Intercept portion of the survey is used to estimate • Average Catch and Harvest Per Crabbing Trip • Crabber eligibility requirements: • * Must be a recreational crabber, or angler who incidentally caught crabs • * At least 1/3 done with their crabbing trip • * Five years of age or older • Completed Interview Target – 850 Intercepts (allocated seasonally & by • crabbing activity) • * Completed 831 interviews – little activity in May and early June • * 230 interviews of boaters, 601 interviews of land crabbing – bridge/bank • * Over 3,200 individual length and sex measurements recorded • Also collected information on crab consumption and eating preferences
Results – Participation • Residential Participation (Tri-County only): • 9.4% of resident households, nearly 11,000, participated in crabbing in 2005 • * Cape May county residents participated most, with 10.7% of households • * 90% of households crabbed together, ave. of 2.3 crabbers per household • * Average monthly participation, 3.5% - peak in August, 8.7%, followed by • September • Overall Participation, Residents and Non: • Tri-county residents accounted for 38.9% of all crabbing activity • * Residential participation peaked in Sept-Oct, 46.9% of all participants • * Non-resident participation also peaked in August, followed by July • New Jersey residents accounted for nearly 82% of all crabbers interviewed • * PA accounted for 16% - crabbers from as • far away as CO, FL, GA, MN and NC • were also interviewed • Ave. # of crabbers each month, resident and non, • – 24,000 individuals!!
Results - Effort • Residential, Tri-County, Effort: • Residents took an estimated 65,000 crabbing trips during season • Cumberland County residents accounted for 55% of all trips • Residents accounted for 44% of the effort (higher than participation) • 2/3 of activity occurred in July & August (approx. 44,000 trips) • No significant differences among gear types used • 56% of trips were shore mode (i.e. bank, pier, overpass etc.), 44% boat mode • Overall Effort, Residents and Non: • 202,000 total recreational crabbing trips • Peak effort occurred in July & August – 69% of all trips • Boat mode trips accounted for 64% of all trips • Non-residents accounted for the majority of boat mode trips – 78% • Shore mode trips equal between resident and non
Results – Catch and Harvest • Recreational Catch Estimates: • 4.17 million crabs caught !! – 66% of catch occurred in July and August • Approx. CPUE was 19 crabs per trip • 54% of catch thrown back, 46% of catch was harvested • Boat mode more productive than shore – average catch 23 vs. 17, respectively • Residents accounted for 30% of catch • Catch by gear types: 40% by collapsible traps, 8% pots, all other 52% • Recreational Harvest Estimates: • 1.92 million crabs harvested!! • Equivalent to approx. 21% of the commercial harvest during same time • Average harvest per trip was about 9 crabs per individual • Boat mode accounted for 74% of harvest (high non-resident component) • Residents accounted for 30% of harvest as well
Results - Biological • Harvest By Sex: • Nearly 75% of the harvest was comprised of males • Harvest sex ratio of 2.93 : 1 males to females • Commercial harvest (statewide) has approx. the same sex ratio • 79% of the female harvest was mature • Harvest By Size: • Average size of females harvest – 139mm (5.5 inches) • Mature female size – 142mm (5.6 inches) • Immature female size – 128mm (5.0 inches) • Average size of males harvested – 135mm (5.3 inches) • These sizes are very consistent with the average size of • harvestable sized crabs in NJ DE Bay trawl survey
Implications/Application • DE Bay Blue Crab Stock Assessment • * Currently no estimate for NJ • * Assumed equivalent to DE estimates, approx. 1.5% of commercial pot harvest • * With these results, stock size estimates are likely to increase (i.e. past • assessments under-estimating stock size) • * Effects on exploitation or fishing mortality of DE Bay stock ? • Fishery-Dependent Size and Sex Data • * Only data NJ has from the fishery on the size/sex/maturity composition of the • harvest • * Comparison/relationships between commercial and recreational fisheries • Baseline for Future Studies in DE Bay • * Starting point or reference for future work in DE Bay • * Potential need to begin more monitoring/surveying the recreational fishery • Pilot/Test Survey for Future Refinement • * Learning from the results (or our mistakes) • * Ex. – reallocation of sampling (interviews, survey area, biological) for 2006 • survey
Future Research & Plans • Southern Atlantic Coastal Bays Survey – 2006 season • * Sampling Area – Cape May Pt. (Jarvis Sound) through Great Bay • * All data collection complete, analysis underway • * Based on 2005 survey in DE Bay – re-allocated target telephone and • intercept interviews more emphasis on telephone calls • Northern Atlantic Coastal Bays Survey– 2007 season? • * Sampling Area – Little Egg Harbor through Sandy Hook • * Specifics (interview targets, intercept locations, etc) of survey not • developed yet • * Funding source not secure • Volunteer Recreational Crab Pot Report • * Started for the 2005 recreational crabbing season • * Provided to everyone who obtains a non-commercial crab pot license • * Information collected: • > Fishing location • > # of crabs caught and kept • > Soak Time and # of pots fished • > Any misc. info or comments – sex ratios, presence of sponge crabs etc.
Acknowledgements ORC Macro Heather Driscoll Nicole Comanducci Randy ZuWallack NJ Marine Fisheries Administration Tom McCloy Paul Scarlett Linda Barry Jeff Brust NJ Marine Law Enforcement Lt. Carl Yunghans C.O. Craig James C.O. Jeremy Trembley National Marine Fisheries Service Rob Andrews Funding through