Monitoring Fishery Catch to Assist Scientific Stock Assessments in Scottish Inshore Fisheries

and

Identifying Catch Composition to Improve Scottish Inshore Fisheries Management using

Technology to Enable Self-Reporting

SeaScope Fisheries Research Ltd.Project Manager – Grant Course

Acknowledgement: Prepared for: Seafish Industry Authority.Comment and review by: Marine Scotland. Funded by: European Fisheries Fund (EFF)

Project Aims

• Recruit and train inshore vessels to self-sample catches for Data Deficient Stocks on Scottish West Coast• Brown Crab

• Lobster

• Velvet Crab

• Scallops

• Nephrops (not a data deficient stock)

• Verify with Electronic Monitoring (EM) equipment

• Carry out subprojects investigating novel approaches for monitoring using technology

Produced by Ali McKnight

Vessel geographic distribution

Electronic monitoring• AMR EM System with control box, cameras (3), GPS, winch rotation

sensor, hydraulic pressure sensor, screen and keyboard

• Archipelago Marine Research v4.5 and v5 units

Equipment setup examples

EM sensor data example – All Haul Positions

Sensor Data – Day View

Video example

• EM systems – 11 vessels for 6 months

• 703 fishing trips undertaken

• 568 provided good quality self-sampled data – 85%

• 6136 strings/tows were self-reported on the valid trips

• Over 180,000 creels were deployed

• 96% of trips provided EM data – majority of losses due to human error

• Video review on 12% of valid trips – 68 trips, 618 strings, 19,002 creels

• 36 At-Sea Observer trips completed• Control and Biological Data (21 trips) – collected over 7400 length and sex

measurements• Weight estimates for retained and discarded catch segments• Data for the 4 Sub-projects (15 trips)

Sampling Summary

Data Comparisons in Report

• Video Review v Self-reported• Retained – count and weight

• Discarded – count and weight

• Sex ratios – count, weight, by eye estimate

• Fishing effort

• Catches per unit effort

• Video Review v At Sea Observer• Pot by Pot Comparisons

• Retained and discarded counts

• Sex ratios

Example of Video Review data - Sex ratio and numbers able to be sexed during video review, for brown crab and velvet crab

4954 368 37611438

5823 460 55101445

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Brown Crab - Discarded Velvet Crab - Discarded Brown Crab - Retained Velvet Crab - Retained

Male Female

76%25% 25%32%Percentage of viewed crabs sexed

Video Review v At-Sea Observere.g. Pot by Pot Comparisons: 763 Creels (overall 1 crab difference in totals 578:579)

Conclusion very similar results so EM video analysis is accurate and able to provide useful catch data.

Technology SubprojectsRFID Tags

• System installed with 2 readers and horns, linked to EM system

RFID PlotsGPS track data overlaid with RFID summary data

Individual pot location plotted using RFID and GPS and summary table of soak time

Next Steps (?) – further develop the integrated system; improve ruggedness and reliability; roll out on larger scale

Data Logger• Cefas datalogger – temperature and depth

DST depth profile

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Max Depth (m) Min Depth (m)

Modified Discard Chute• Chute design

• 3 cameras, a shaded area to eliminate sun glare, and a small hopper (not shown) to allow more automated delivery

Self Sampled Biological Data• Aim – to have fishermen gather verified length and sex data without

undue burden

• Mitutoyo digital callipers fitted with Bluetooth adaptor• Male/female buttons, vibration, length data sent to tablet/phone/laptop,

Excel.

Crab calliper video

Project conclusionsSelf-Sampling

• Fishermen are capable of providing large quantities of good quality data (85% datasheet returns), which could easily be improved

• Self-sampling provides –• good retained catch estimates

• less reliable on discard estimates especially when large quantities

• good effort data for days at sea and strings

• number of creels are usually underestimated

• sex ratio data reliability varied depending on how data was collected

• soak time is unreliable as strings have varied times on same trip

• length data – can be provided efficiently using Bluetooth callipers

Electronic Monitoring

• EM works on smaller inshore vessels and can verify self-reported catch data (96% success but most issues related to install errors not system errors <1%)

• EM sensors and video review provides –• Excellent counts of retained and discarded catches, weights are harder to

obtain

• 100% of collected effort data at location – days at sea/strings/tows deployed

• Excellent creel counts on reviewed trips only (RFID may automate – all hauls)

• Soak time more difficult to obtain than expected (RFID/DST may resolve this)

• Sex ratios obtainable for crabs but not lobsters, discards harder to see and time consuming (modified chute may help)

• Length data obtainable from video review using modified chute (also counts and sex)

Thank you for listening

SeaScope Fisheries Research Ltd.

Acknowledgement: Prepared for: Seafish Industry Authority.Comment and review by: Marine Scotland. Funded by: European Fisheries Fund (EFF)