VTechWorks staff will be away for the Independence Day holiday from July 4-7. We will respond to email inquiries on Monday, July 8. Thank you for your patience.
 

The effects of life history strategy and uncertainty on a probability-based approach to managing the risk of overfishing

dc.contributor.authorSusko, Emily Clareen
dc.contributor.committeechairBerkson, James M.en
dc.contributor.committeememberJiao, Yanen
dc.contributor.committeememberConn, Paulen
dc.contributor.committeememberOrth, Donald J.en
dc.contributor.departmentFisheries and Wildlife Sciencesen
dc.date.accessioned2017-04-04T19:50:25Zen
dc.date.adate2012-04-17en
dc.date.available2017-04-04T19:50:25Zen
dc.date.issued2012-02-17en
dc.date.rdate2016-10-18en
dc.date.sdate2012-03-02en
dc.description.abstractRecent U.S. legislation applies a precautionary approach to setting catch regulations in federal fisheries management. A transparent approach to complying with federal guidelines involves calculating the catch recommendation that corresponds to a specified probability, P*, of exceeding the "true" overfishing limit (OFL) located within an estimated distribution. The P* methodology aims to manage the risk of overfishing explicitly, but choice of P* alone does not provide sufficient information on all of the risks associated with a control rule—both the probability of overfishing and the severity of overfishing. Rather, the ramifications of P* choices depend on the amount of uncertainty in the stock assessment and on the life history of the species in question. To evaluate these effects on the risks associated with P* rules, my study simulated fishing three example species under three levels of uncertainty. Trends identified among example species were consistent with predictions from life history. Periodic strategists, which have highly variable recruitment, experienced probabilities of overfishing which exceeded P* and which increased in time. Equilibrium strategists showed more predictable risks of overfishing but may have less capacity to recover from depleted biomass levels. Differences in the size of the OFL distribution—representing differences in levels of uncertainty—led to mixed results depending on whether the distribution was biased or whether uncertainty was fully characterized. Lastly, because OFL distributions are themselves estimates and subject to uncertainty in their shape and size, lower P* values closer to the tails of the estimated distribution produced more variable resulting risks.en
dc.description.degreeMaster of Scienceen
dc.identifier.otheretd-03022012-012029en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-03022012-012029/en
dc.identifier.urihttp://hdl.handle.net/10919/76939en
dc.language.isoen_USen
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectgulf menhadenen
dc.subjectsimulation modelen
dc.subjectlife historyen
dc.subjectsandbar sharken
dc.subjectuncertaintyen
dc.subjectrisken
dc.subjectfisheries managementen
dc.subjectvermilion snapperen
dc.subjectstock assessmenten
dc.titleThe effects of life history strategy and uncertainty on a probability-based approach to managing the risk of overfishingen
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineFisheries and Wildlife Sciencesen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
etd-03022012-012029_Susko_EC_T_2012.pdf
Size:
8.35 MB
Format:
Adobe Portable Document Format

Collections