MRIP UPDATE: Improving Recreational Catch Estimation New England Fishery Management Council Recreational Advisory Panel - November 1, 2011 Paul Perra NOAA Fisheries Service Gloucester, MA.
Marine Recreational Information Program (MRIP) 2
Agenda – Totally Focused to Provide the Best Information 3
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. 4
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. 5
How Data Are Used Collecting Fishery Data management decisions are based on a Assessing Quality continuous cycle. Making Fishery Data is Regulations Health Critical Our goal is to ensure fisheries remain productive – now and for Setting Catch generations to Targets come. 6
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. 7
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. 8
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 9
The Effect of BIAS Precise, but Precise and inaccurate accurate 10
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 11
What’s Changing Matching Sampling Designs What We’ve Done in What We’re Fixing Changes to New Changes to New the Past Catch Estimation Shoreside Sampling Design Design We assumed our Shoreside sampling The new estimation N/A. A multi-stage shoreside sampling design was not truly method is appropriate cluster sample design was random and random, but rather a for a multi-stage will still be used. therefore multi-stage cluster cluster sample. Our We will emphasize representative of the design. designs for sampling getting complete whole population of anglers and counts of anglers and anglers. estimating catch are boats at sites now matched. sampled. 12
What’s Changing Measuring Catch per Trip What We’ve Done in What We’re Fixing Changes to New Changes to New the Past Catch Estimation Shoreside Sampling Design Design We assumed that We’re testing the The new estimation We will sample sites catch sampled during assumption that non- method is weighted during 4 specified peak times could peak catch differs to account for catch six-hour blocks. accurately estimate significantly from during all periods of Sampling during both catch across an peak period catch. the day. peak and non-peak entire 24-hour period. times will enable us to more accurately estimate catch 13 across a whole day
What’s Changing More Representative Sampling of Modes What We’ve Done in What We’re Fixing Changes to New Changes to New the Past Catch Estimation Shoreside Sampling Design Design Samplers’ site The selection probability Data collected for Samplers will only assignments were of the site for the “alternate mode” trips collect data for the mode for which the site selected based on the alternate modes sampled at primary was selected. pressure rating by sampled cannot be assigned sites will not mode, day type and determined. Therefore, be used in new month. However, it is not possible to estimates. samplers had discretion weight the estimate to to sample alternate account for the true mode trips that they selection probability. observed occurring at 14 the assigned site
What’s Changing More Representative Sampling of Sites What We’ve Done in What We’re Fixing Changes to New Changes to New the Past Catch Estimation Shoreside Sampling Design Design Site assignments were The selection Selection probabilities of Samplers will conduct based on PPS sampling probabilities of the the alternate sites have interviews at a specific based on the pressure alternate sites were not been estimated (model- cluster of sites in a specific rating by mode, day type known. Therefore, the based method), and the randomized order for the and month. However, estimates were not estimates have been re- full time period, ensuring samplers were allowed weighted properly to weighted to account for more structured sampling to move to an alternate account for the alternate them. and less sampler site of their choice after 2 site selection discretion. hours if there was little or probabilities. no activity at the assigned site. 15
Anatomy of an Estimate Removing potential bias affects both the point estimate and its associated measure of Point Estimates precision , expressed Precision either as the Percent Standard Error (PSE) or graphically as the Confidence Interval. 16
Do the new numbers “Trump“ the old numbers” ? 17
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. 18
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. 19
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 20
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 21
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. 22
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. 23
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. 24
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 25
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