Download or read book Estimating Persistence of Fished Populations with Limited Data written by Michael Robert O'Farrell and published by . This book was released on 2005 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book QUANTITATIVE APPROACHES FOR THE ANALYSIS OF MORTALITY IN MARINE FISH POPULATIONS written by Hugues Pascal Benoît and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fisheries science has historically focused on recruitment variability and fishery landings as key drivers of dynamics in populations exposed to fishing. However, comprehending the persistence of these populations and successfully managing fishing impacts on them depends on understanding the magnitude, dynamics and causes of mortality from all sources. In this thesis, I develop a series of approaches for the analysis or estimation of discard and natural mortality, two key sources of mortality that have often previously been overlooked. In chapters two and three I present methods for estimating indicators of discard mortality (DM). These approaches provide simple and cost-effective means to evaluate the influence of factors affecting DM and case-specific risks posed by DM, and to improve formal DM estimates in directed studies. In chapters four and five, I present a case study for the estimation of fishing mortality for principally discarded species, skates in the southern Gulf of St. Lawrence (sGSL; Atlantic Canada). Estimating fishing mortality for these species of conservation concern poses several challenges, including catch reporting that is not disaggregated to species and that is somewhat sparse. I derive and apply a method to disaggregate the catches and an integrated approach, based in part on the methods from chapter two, to estimating landed and discarded catch amounts and DM rates. In chapter six, I develop and validate a model for data from DM experiments that is generalizable to estimate different components of mortality, including jointly estimating discard and natural mortality. Finally in chapter 7, I develop a simulation model to evaluate whether predation by a top predator is a scientifically defensible explanation for elevated natural mortality in three fish species of conservation concern in the sGSL. This approach is presented as a means of evaluating the possible consequences of predation in the absence of reliable estimates of predator diets. Together, the methods developed in this thesis represent new tools for the estimation of mortality components and for the attribution of their likely drivers. In turn, these tools should help inform management actions aimed at mitigating mortality or sustainably managing populations and communities in light of existing mortality.
Download or read book General Technical Report INT written by and published by . This book was released on 1993 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fishery Bulletin written by and published by . This book was released on 1992 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Dynamics for Conservation written by Louis W. Botsford and published by Oxford University Press. This book was released on 2019-09-26 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The management and conservation of natural populations relies heavily on concepts and results generated from models of population dynamics. Yet this is the first book to present a unified and coherent explanation of the underlying theory. This novel text begins with a consideration of what makes a good state variable, progressing from the simplest models (those with a single variable such as abundance or biomass) to more complex models with other key variables of population structure (including age, size, life history stage, and space). Throughout the book, attention is paid to concepts such as population variability, population stability, population viability/persistence, and harvest yield. Later chapters address specific applications to conservation such as recovery planning for species at risk, fishery management, and the spatial management of marine resources. Population Dynamics for Conservation is suitable for graduate-level students. It will also be valuable to academic and applied researchers in population biology. This overview of population dynamic theory can serve to further their population research, as well as to improve their understanding of population management.
Download or read book Contribution to the Methodology of Estimating Fish Populations in Warmwater Streams written by Peter E. Zurbuch and published by . This book was released on 1957 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimation of Age Structure of Fish Populations from Length frequency Data written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A probability model is presented to determine the age structure of a fish population from length-frequency data. It is shown that when the age-length key is available, maximum-likelihood estimates of the age structure can be obtained. When the key is not available, approximate estimates of the age structure can be obtained. The model is used for determination of the age structure of populations of channel catfish and white crappie. Practical applications of the model to impact assessment are discussed.
Download or read book The Progressive Fish culturist written by and published by . This book was released on 1980 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Progressive Fish Culturist written by U.S. Fish and Wildlife Service and published by . This book was released on 1981 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Climate Change and Northern Fish Populations written by National Research Council Canada and published by NRC Research Press. This book was released on 1995 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt: These documents summarize some of the recent studies of the relationships among climate, the aquatic environment, and the dynamics of fish populations. The studies are mostly from the North Pacific ocean, but there are reports of investigations from the North Atlatic Ocean and from fresh water. Various papers include numerous examples of the relationships between fish abundance trends and the environment.
Download or read book Size based assessment of data limited inland fish stocks Review and applications written by Shephard, S., Valbo-Jorgensen, J., Abadía, J., Baigún, C., Doria, C.R.C., Fabré, N.N., Isaac, V.J., Ngor, P.B., Ruffino, M.L., Funge-Smith, S.J. and published by Food & Agriculture Org.. This book was released on with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Assessment of data-limited fish stocks is a rapidly evolving topic in marine fisheries, and is supported by an increasing focus on the socio-economic and ecological importance of small-scale fisheries. The challenges in such systems can be compounded in inland fisheries, which are often complex, spatially dispersed and difficult to monitor. This publication reviews the application of empirical indicators and simple size-based models usually used in marine fisheries, but also applicable in inland systems. It presents case study applications for important fisheries in the Amazon River (Brazil), Tonlé Sap River (Cambodia), Paraná River (Argentina) and Lago Bayano (Panama). These studies consider issues including spatial separation of life-history stages, strong modality in population size structure, and fishing gear selectivity. Local scientific experts interpreted trends in stock state. Empirical indicators showed strong decline in size structure and relative abundance for one of the four assessed Tonlé Sap stocks. The length-based spawning potential ratio model suggested that two of the three assessed Amazon Goliath catfish stocks, and the sábalo stock in the Paraná River, were below sustainable spawning potential ratio reference points. The Lago Bayano tilapia stock appeared healthy. The review concludes that data-limited assessment methods developed for marine stocks may provide guidance for the sustainable management of important target species in inland fisheries. The methods tested are probably less applicable in non-selective fisheries where small species are preferred, or in river fisheries with extreme dependence on flood pulses. Important considerations are species life history and spatial distribution, environmental variability, and fishery sampling strategy.
Download or read book Computation and Interpretation of Biological Statistics of Fish Populations written by William Edwin Ricker and published by . This book was released on 1978 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Methods in Using Mark recapture Data for Population Estimation written by and published by . This book was released on 1967 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spatial Capture Recapture written by J. Andrew Royle and published by Academic Press. This book was released on 2013-08-27 with total page 609 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spatial Capture-Recapture provides a comprehensive how-to manual with detailed examples of spatial capture-recapture models based on current technology and knowledge. Spatial Capture-Recapture provides you with an extensive step-by-step analysis of many data sets using different software implementations. The authors' approach is practical – it embraces Bayesian and classical inference strategies to give the reader different options to get the job done. In addition, Spatial Capture-Recapture provides data sets, sample code and computing scripts in an R package. - Comprehensive reference on revolutionary new methods in ecology makes this the first and only book on the topic - Every methodological element has a detailed worked example with a code template, allowing you to learn by example - Includes an R package that contains all computer code and data sets on companion website
Download or read book Demographic and Habitat Requirements for Conservation of Bull Trout written by Bruce E. Rieman and published by . This book was released on 1993 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Boise National Forest N F Boise River Wildlife Recovery Project Boise County Elmore County written by and published by . This book was released on 1995 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Risk Evaluation and Biological Reference Points for Fisheries Management written by National Research Council Canada and published by NRC Research Press. This book was released on 1993 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers presented: 1) Reference points for fisheries management: the western Canadian experience; 2) Reference points for fisheries management: the eastern Canadian experience; 3) Reference points for fisheries management: the ICES experience; 4) Spawning stock biomass per recruit in fisheries management: foundation and current use; 5) The development of a management procedure for the South African anchovy resource; 6) How much spawning per recruit is enough?; 7) The behaviour of Flow, Fmed and Fhigh in response to variation in parameters used for their estimation; 8) The Barents Sea capelin stock collapse: a lesson to learn; 9) Variance estimates for fisheries assessment: their importance and how best to evaluate them; 10) Evaluating the accuracy of projected catch estimates from sequential population analysis and trawl survey abundance estimates; 11) Bootstrap estimates of ADAPT parameters, their projection in risk analysis and their retrospective patterns; 12) Analytical estimates of reliability for the projected yield from commercial fisheries; 13) Risk evaluation of the 10% harvest rate procedure for capelin in NAFO Division 3L; 14) Using jackknife and Monte Carlo simulation techniques to evaluate forecast models for Atlantic salmon; 15) Monte Carlo evaluation of risks for biological reference points used in New Zealand fishery assessments; 16) A comparison of event free risk analysis to Ricker spawner-recruit simulation: an example with Atlantic menhaden; 17) Choosing a management strategy for stock rebuilding when control is uncertain; 18) Risks and uncertainties in the management of a single-cohort squid fishery: the Falkland Islands Illex fishery as an example; 19) Risks of over- and under-fishing new resources; 20) Estimation of density-dependent natural mortality in British Columbia herring stocks through SSPA and its impact on sustainable harvesting strategies; 21) The comparative performance of production-model and ad hoc tuned VPA based feedback-control management procedures for the stock of Cape hake off the west coast of Africa; 22) A proposal for a threshold stock size and maximum fishing mortality rate; 23) Biological reference points for Canadian Atlantic gadoid stocks; 24) Stochastic locally-optimal harvesting; 25) ITQ based fisheries management; 26) Bioeconomic methods for determining TACs; 27) Management strategies: fixed or variable catch quotas; 28) Bioeconomic impacts of TAC adjustment strategies: a model applied to northern cod; 29) Experimental management programs for two rockfish stocks off British Columbia; 30)A brief overview of the experimental approach to reducing uncertainty in fisheries management; 31) Fisheries management organizations: a study of uncertainty.
