Overview Outline National Research Council Review. Description of StudyMajor Recommendations in ReportSpecific Recommendations for:Sampling DesignStatistical EstimationProgram Management and SupportCommunications and Outreach. National Research Council Review October 2004
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1. Overview of National Research Council Recommendations for Recreational Fisheries Surveys Dave Van Voorhees
NMFS Fisheries Statistics Division
RecFIN Technical Committee Member
PSMFC, Chair of RecFIN Technical Committee
2. Overview Outline National Research Council Review Description of Study
Major Recommendations in Report
Specific Recommendations for:
Program Management and Support
Communications and Outreach
3. National Research Council Review October 2004 – April 2006 Review of current recreational fisheries survey methods supported by NOAA Fisheries Service
Conducted by NRC Ocean Studies Board under contract established and funded by NOAA Fisheries Service
Prospectus (Statement of Task) submitted in August 2004
Ten-member committee formed to conduct review
Five meetings held in 2005:
March 10-11: Washington, DC
May 19-21: San Francisco, CA
July 7-9: New Orleans, LA
September 22-24: New York, NY
October 26-28: Tampa, FL
Report delivered in April 2006
4. National Research Council ReviewGroups Represented at Public Meetings NOAA Fisheries Service:
Other Government Agencies:
Fisheries and Oceans Canada
U.S. Dept. Agriculture
Florida State University
Old Dominion University
Wostmann and Associates
5. National Research Council ReviewGroups Represented at Public Meetings State Agencies:
New York DEC
North Carolina DMF
American Sportfishing Assoc.
Coastal Conservation Assoc.
Recreational Fishing Alliance
National Assoc. Charterboat Operators
Golden Gate Fisherman’s Assoc.
Jersey Coast Angler’s Assoc.
Fishing Rights Alliance
6. National Research Council Review Statement of Task This study will critically review the types of survey methods used to estimate catch per unit effort and effort in recreational fisheries, including state/federal cooperative programs.
The committee will examine representative survey types, but will not evaluate every regional or state survey method currently in use.
The study will consider the match or mismatch between options for collecting recreational fisheries data and alternative approaches for managing recreational fisheries.
7. National Research Council Review Questions Addressed
How suitable are current survey methods for monitoring different types of recreational fishing?
Do current methods provide the statistical quality needed to support current spatiotemporal frames for management?
How should frames of reference for management be limited by choice of survey method, stratification scheme, and/or sample sizes?
How would the survey design need to be modified to match the requirements of the management approach?
Are there alternative methods or changes to current methods that could improve the quality and utility of fishery statistics?
8. National Research Council Review Major Recommendations “This committee’s review has focused primarily on the MRFSS, but many of the component surveys of the MRFSS conducted by state agencies (with various degrees of federal funding) suffer from the same shortcomings as does the central MRFSS.
As a result, many of this committee’s recommendations apply to state surveys as well as to the MRFSS.”
9. National Research Council Review Major Recommendations Set firm deadline linked to sufficient program funding to implement the Report’s recommendations.
Re-design current survey programs to improve:
sampling and estimation procedures,
applicability to various kinds of management decisions, and
usefulness for social and economic analyses.
Provide ongoing technical evaluation and modification to meet emerging management needs.
Achieve much greater degree of standardization among state and federal surveys.
Treat For-Hire sector as “commercial” and establish mandatory requirements for timely reporting.
10. Sampling Design:Survey Frames Develop more complete, accurate, and efficient survey sampling frames
Establish universal angler list frame for future telephone surveys
Re-design/expand site/day list frames for on-site surveys conducted at access points to fishing
Establish universal for-hire vessel list frames for mandatory reporting surveys
11. Sampling Design:Telephone Survey Frames Establish comprehensive, universal angler sampling frame with national coverage
Compile through National registration and/or coordination of State saltwater licensing programs
Must provide appropriate contact information
Must include both state and federal waters anglers
Should be restricted to anglers fishing in marine waters
Must not allow exemptions
Must be stored in automated, frequently updated database
Base future telephone surveys of recreational fishing on this universal angler sampling frame
12. Sampling Design:Telephone Survey Frames If angler list frame not available, use random-digit-dialing household survey frame
only viable option in states without a complete registration of marine recreational anglers
less efficient than angler list frame approach
greater potential for bias
efficiency and possible biases may get worse as usage of cell phones and answering machines continue to increase
13. Sampling Design:Access-Point Survey Frames Re-design/expand site/day sampling frames
Include all fishing sites and access points
Include all different times of day
Use consistent methods for estimating site/day fishing pressures and assigning selection probabilities for sampling
Revise sampling protocols to assure:
Random probability sampling of site/day units
Appropriate on-site sampling of angler, or vessel trips
Improve sampler adherence to protocols
Improved sampler training
More extensive/effective QC monitoring of samplers
14. Sampling Design:For-Hire Sector Treat For-Hire sector as a “commercial” sector
Develop complete list frame of participating for-hire vessels
Establish mandatory reporting requirements:
Census effort and catch through vessel trip reports, or logbooks
Must include all effort
Must include both landed and released catches of fish
Must be timely and verifiable
Compliance must be adequately enforced
Potential to collect more detailed trip information
Verify self-reported data:
Rigorous on-site sampling program to verify effort
On-Site/At-Sea sampling surveys to verify catch
Sampling surveys may be more appropriate where:
For-Hire sector takes small component of catch
Verification and enforcement are problematic
15. Sampling Design:Released Catch Data Conduct additional studies to improve verification and estimation of catch not brought to the dock, especially released catch
On-Site surveys need to distinguish between:
Fish kept/available for inspection (observed)
Fish not available for inspection (unobserved)
Need to independently verify unobserved, self-reported catches
16. Sampling Design:Dual-Frame Surveys Dual-frame surveys should be used wherever possible to reduce sample bias.
Example: dual-frame telephone surveys
Incomplete list frame of licensed anglers (L)
RDD frame of coastal households (H)
Example: dual-frame vessel surveys
List frame of federally permitted vessels (P)
List frame of all known vessels (V)
Example: dual-frame on-site/off-site surveys
Incomplete list frame of fishing access points (AP)
Complete list frame of licensed anglers (L) or RDD frame of coastal households (H)
17. Sampling Design:Panel and Internet Surveys Consider conduct of panel surveys
Improving efficiency of data collection
MRFSS Coastal Household Telephone Survey:
Repeated contacts of known fishing households
Gathering angler or vessel trend data
Angler or vessel diary surveys?
Catch and effort for private vs. public access trips?
Catch and effort for daytime vs. nighttime trips?
Consider use of internet surveys, especially in panel surveys
18. Statistical Estimation:Assumptions and Potential Biases Determine statistical properties of various sampling, data-collection, and data-analysis methods.
Current designs, sampling strategies, and collection methods do not provide adequate information for management and policy decisions.
Unknown biases in estimators arise from reliance on unverified assumptions.
Examine and verify assumptions so that biases can be properly evaluated.
Without evaluation of possible biases, the reliability of final estimates remains unknown.
19. Statistical Estimation:Assumptions about Non-Sampled Units Test assumptions used in expanding estimates over non-sampled segments of angling population
Telephone surveys – are missed anglers different?
MRFSS Coastal Household Survey:
non-residents of coastal zone
coastal zone residents without landline phones
Angler License Directory Surveys:
licensed anglers not providing contact information
Access-Point intercept surveys – are missed trips different?
Private access trips
private docks, private shorelines, private locked marinas
20. Statistical Estimation:Assumptions and Potential Biases Evaluate and verify assumptions so that potential biases can be evaluated.
Examine possible errors of representation
Frame coverage errors
Are random probability samples always obtained?
Are selection probabilities of all sample frame units known?
Do sample means differ among frame units with different probabilities of selection?
21. Statistical Estimation:Assumptions and Potential Biases Analyze potential biases within the current sampling and estimation designs wherever possible using existing data.
Use selection probabilities in estimation process.
Household telephone surveys – household probabilities
Access-point intercept surveys – site/day probabilities
Account for multi-stage cluster sampling designs
Site/day clusters of angler, or vessel, trips
Fishing vessel clusters of angler trips
“Mixed Catch” clusters of angler trips
Vessel and angler clusters of observed fish
Include covariance terms where appropriate when estimating variances of aggregated estimates that are not independent
Aggregations of estimates across modes, areas, or trip types
22. Cluster Sampling
23. Statistical Estimation:Sample Sizes, Stratification, and Timeliness Users want statistics at finer levels of spatial and temporal resolution.
Increase precision at lower levels of resolution.
Increase sample sizes
Optimize sample allocations
Increase timeliness of availability of survey data and statistics to better support timely fishery management decisions.
24. Program Management and Support:Survey Design and Execution Add expertise and personnel needed to continually evaluate and improve survey design and execution
Increase expertise of existing staff through training
Recruit new staff with appropriate expertise
Hire consultants with appropriate expertise as needed
Survey statisticians and managers must collaborate effectively with:
Population scientists – to design data collection protocols and summary statistics that support population assessments
Fishery managers – to design spatiotemporal sampling and estimation schemes that match management frames
25. Program Management and Support:Statistical Support Form research group of statisticians to design new analyses based on developments in sampling theory
Surveys of nighttime fishing and private access fishing?
Explore possible use of model-based or model-assisted “survey regression estimators”
Possible use of business-related or weather-related covariates?
Explore possible use of “small domain” estimation methods that employ indirect “synthetic” or “composite” estimators.
May be possible to “borrow strength from entire sample” to fit regression model relating response variable to covariates and predicting all elements in a given “small domain”.
26. Program Management and Support:Evaluation, Modification, and Coordination Establish ongoing technical evaluation and modification to meet emerging management needs
Providing fluid, continuous review and feedback
Invest significantly in intellectual/technical expertise
Establish and fund Independent Research Group (IRG)?
Continuously evaluate statistical design/adequacy of surveys
Guide necessary modifications or new initiatives
Improve Federal/State coordination to gain National perspective on marine recreational fisheries
Fund separate Survey Office?
Manage and implement surveys
Coordinate state and federal survey efforts
27. Communications and Outreach Improve communications, outreach, and education
Advise, inform, and educate:
Advise on constraints for various possible uses of statistics
Inform about any limitations of raw data or estimated statistics
Educate about sampling designs and data collection processes
Institutionalize outreach and communication
Establish as part of an ongoing program
Develop appropriate communications expertise
Engage angler associations as partners
Involve them in workshops, data collection, and survey design
Encourage participation in survey advisory groups.