MRIP UPDATE: Improving Recreational Catch Estimation New England - - PowerPoint PPT Presentation

MRIP UPDATE: Improving Recreational Catch Estimation

New England Fishery Management Council Recreational Advisory Panel - November 1, 2011 Paul Perra NOAA Fisheries Service Gloucester, MA.

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Marine Recreational Information Program (MRIP)

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Agenda – Totally Focused to Provide the Best Information

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Topics Covered

• Catch estimation overview and context
• Why a new catch estimation method has

been a top MRIP priority.

• What to expect from the new estimates.
• What else we’re doing to improve

estimates.

• Partnering with the States for

implementation

• What’s the timeline.

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Estimating Recreational Fishing Catch and Effort

NOAA Fisheries provides two estimates of recreational fishing activity:

• Catch, or the number, species and size of fish caught.
• Generally determined through shore-side intercepts.
• Effort, or the number of fishing trips taken during a

particular reporting period.

• Generally determined through telephone surveys.

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How Data Are Used

Collecting Data Assessing Fishery Health Setting Catch Targets Making Regulations Fishery management decisions are based on a continuous cycle. Our goal is to ensure fisheries remain productive – now and for generations to come. Quality Data is Critical

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The Marine Recreational Information Program - Moving Into a New Era of Data Collection

Created in 2007 to address:

• Recommendations of the

National Research Council’s Review of Recreational Fisheries Survey Methods.

• New requirements of the 2006

Magnuson-Stevens Act.

• Stakeholder confidence in

catch and effort estimates.

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NRC Findings on Catch Estimation Method

• Estimation process is not matched to how we gather data.
• Shore-side sampling methods emphasize maximizing

angler intercepts at the expense of statistical rigor.

• These two factors inserted potential for bias into the point

estimates and their precision.

NRC recommended we fix both the way we estimate catch and the way we gather data.

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Our Top Priority

The potential for bias was the NRC’s chief concern about MRFSS

potential for bias is the result of unaccounted for factors or untested assumptions

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The Effect of BIAS

Precise, but inaccurate Precise and accurate

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The Statistical Team

• Dr. Jay Breidt, Colorado State University
• Dr. Jean Opsomer, Colorado State University
• Dr. Han-lin Lai, NOAA Fisheries
• Dr. Dave Van Voorhees, NOAA Fisheries

John Foster, NOAA Fisheries

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What’s Changing Matching Sampling Designs

What We’ve Done in the Past What We’re Fixing Changes to New Catch Estimation Design Changes to New Shoreside Sampling Design We assumed our shoreside sampling was random and therefore representative of the whole population of anglers. Shoreside sampling design was not truly random, but rather a multi-stage cluster design. The new estimation method is appropriate for a multi-stage cluster sample. Our designs for sampling anglers and estimating catch are now matched. N/A. A multi-stage cluster sample design will still be used. We will emphasize getting complete counts of anglers and boats at sites sampled.

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What We’ve Done in the Past What We’re Fixing Changes to New Catch Estimation Design Changes to New Shoreside Sampling Design We assumed that catch sampled during peak times could accurately estimate catch across an entire 24-hour period. We’re testing the assumption that non- peak catch differs significantly from peak period catch. The new estimation method is weighted to account for catch during all periods of the day. We will sample sites during 4 specified six-hour blocks. Sampling during both peak and non-peak times will enable us to more accurately estimate catch across a whole day

What’s Changing Measuring Catch per Trip

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What We’ve Done in the Past What We’re Fixing Changes to New Catch Estimation Design Changes to New Shoreside Sampling Design

Samplers’ site assignments were selected based on the pressure rating by mode, day type and

• month. However,

samplers had discretion to sample alternate mode trips that they

• bserved occurring at

the assigned site The selection probability

• f the site for the

alternate modes sampled cannot be

• determined. Therefore,

it is not possible to weight the estimate to account for the true selection probability. Data collected for “alternate mode” trips sampled at primary assigned sites will not be used in new estimates. Samplers will only collect data for the mode for which the site was selected.

What’s Changing

More Representative Sampling of Modes

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What We’ve Done in the Past What We’re Fixing Changes to New Catch Estimation Design Changes to New Shoreside Sampling Design

Site assignments were based on PPS sampling based on the pressure rating by mode, day type and month. However, samplers were allowed to move to an alternate site of their choice after 2 hours if there was little or no activity at the assigned site. The selection probabilities of the alternate sites were not

• known. Therefore, the

estimates were not weighted properly to account for the alternate site selection probabilities. Selection probabilities of the alternate sites have been estimated (model- based method), and the estimates have been re- weighted to account for them. Samplers will conduct interviews at a specific cluster of sites in a specific randomized order for the full time period, ensuring more structured sampling and less sampler discretion.

What’s Changing

More Representative Sampling of Sites

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Removing potential bias affects both the point estimate and its associated measure of precision, expressed either as the Percent Standard Error (PSE) or graphically as the Confidence Interval.

Point Estimates

Precision

Anatomy of an Estimate

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Do the new numbers “Trump“ the old numbers” ?

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Potential Impact of Changes

Changes in catch estimates can affect:

• Stock assessment results
• Is the stock overfished? What’s the biomass?
• Management actions
• What’s the appropriate catch limit? Are we

under or over the catch limit?

Where there are significant changes in the estimates, revisions to fishing regulations may be necessary.

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What’s Next

• Complete the new MRIP catch estimates for 2004 to

2011 and release the updated estimates.

• 2011Nov/Dec In-House Review – January 2012 Release
• Ongoing QA/QC review of method, coding and

programming, legacy data.

• Parallel evaluation of estimates produced by new vs. old

methodology.

• Strategy for updating management to synchronize with

improved estimates.

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What’s Next-2

• Improvements to the design of the Access Point Angler

Intercept Survey (Angler Intercept Survey or APAIS).

• Reducing sampler discretion.
• Enhancing statistical precision.
• Improvements to effort estimates.
• Dual-frame mail/phone surveys
• Use of National Saltwater Angler Registry.
• Enhancing precision through increased sampling.
• Evaluating trade-offs of resource allocation.
• Meeting requirements for ACLs and AMs

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What’s Next- Specific for NER

• Dual frame sampling
• Review of data back to 2004
• Option of electronic reporting for

party/charter

• Sampling of night fishing
• Better estimates
• Recreational fishing forums and

workshops

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Angler Intercept Survey Improvements

• NMFS will plan for implementation of new Angler

Intercept Survey design over the next 8 months

• Key tasks:
• Finalize design elements, i.e. size/definition of sites;

site pressure groupings;

• Update site register with pressures for all time blocks;
• New Procurement;
• Determine sample size.

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Angler Intercept Survey Improvements-2

• State support needed:
• States participate in updating site register (ACCSP Rec

Tech call, Wave Meeting);

• Consider increasing state partner participation in data

collection.

• NMFS actions needed:
• Workshop (web-based?) this fall/winter to identify and

develop strategies to respond to challenges to states, including discussion of sample size issues;

• Funding to support incremental costs of new design.

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Improving Effort Estimates

• Effort is the number of angler trips that occur during a

given time period.

• Under MRFSS, effort estimates relied primarily on

telephone surveys conducted through random-digit dialing of coastal households.

• Potential issues include:
• Calls to households with no fishermen.
• No calls to non-coastal households with fishermen.
• No surveys of households without land lines.
• Response rates and recall issues associated with telephone surveys.

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Improving Effort Estimates-2

Accounting for possible under-estimates of effort by testing:

• Phone surveys (angler license directory only)
• Phone surveys (random digit dialing + license directory)
• Mail surveys (postal service addresses +

license directory)

National Saltwater Angler Registry

• Federal registration started January 1, 2010

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Improving Effort Estimates-3

MOAs in place with all Atlantic states. Each state has provided initial data. Next steps:

• Data evaluation (ongoing)
• Data improvement plans per MOAs
• Second round of grants this winter

Mixed mode dual frame survey expanded pilot in South Atlantic beginning Wave 6 2011; then coastwide expansion in 2012, consistent with pilot results and peer review of methodology

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Other Upcoming MRIP Activities

• For-hire survey: Gulf pilot and beyond
• Timeliness Workshop: improving capability for

in-season management

• Private Access undercoverage bias study
• Angler self-reporting programs workshop
• Large Pelagics Survey

expansions/improvements

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Implementation Timing

• Revised MRIP estimates for 2004 to 2010 and

preliminary 2011 Waves in 2012

• Expanded pilot of “mixed mode” dual frame effort

survey in South Atlantic region beginning Wave 6, 2011.

• Implementation of new shore-side intercept design

for Atlantic coast -TBA.

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Key Takeaw ays

• 1. The new estimation methods will yield more accurate

numbers with a known level of precision.

• Estimates can be made more precise through committing the resources to

increased sample sizes.

• 4. We will be working closely with state partners and the

recreational fishing industry as we proceed with implementation

• 2. This exhaustively researched, peer-reviewed

methodology is a fundamental improvement that allows for a range of future enhancements.

• 3. Additional changes are underway to improve sampling

methodology and address effort issues.

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MRIP Questions

You will soon be able to query the new estimates using the comparison tool at www.CountMyFish.noaa.gov. NMFS contact for detailed MRIP questions is: gordon.colvin@noaa.gov or (301) 427-8118

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MRFSS Estimation “The Old Way”

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MRIP Weighted Estimation “The New Way”

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