Acronym GenoPopTaille
Category
Fisheries
Title Estimating absolute size of endangered marine populations from genetically identified parent-offpring pairs Programme National Programme
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source National Coordinator Pascal Lorance Coordinator email NA
Coordinator institution
IFREMER - French Research Institute for Exploitation of the Sea (France)
Institutions involved
UBO - University of Western Brittany (France) ,
Start year 2014 End year 2018 Funding (€) € 458,428 Website https://anr.fr/Project-ANR-14-CE02-0006 Summary At ecosystem level, sustainable exploitation of fisheries resources depends not only on the status of populations of target species but also on that of populations of bycatch species, some of which are more sensitive to exploitation than target species. This is the case for a number of ray and shark species whose abundance declined during the 20th century, in certain cases severely. Further, the biology of rays and sharks is still poorly known and traditional fisheries stock assessment methods using fisheries catches and scientific survey data for estimating abundance are expensive or even inapplicable due to the small numbers observed.
Recently a new method based on the genetic identification of parent-offspring pairs has been developed to estimate the absolute size of small populations. The method relies on the principle of capture-mark-recapture which is well tested using physical tags, but using genetic marking of parents and recapture via their offsprings. However, this method is still very little used for marine fisheries resources, with few final results published, because of the costs and technical difficulties of applying of genetic tools at the scale of a whole marine population.
The rapid progress of genomic technics during the last decade now allows for high-throughput sequencing and genotyping of large samples for several hundreds or thousands of genetic tags. The GenoPopTaille project will develop a novel application of these genomic technics to estimate the absolute number of thornback ray, Raja clavata, in the Bay of Biscay based on genetic identification of parent-offspring pairs. The thornback ray was chosen for this project because its total abundance is presumed small enough for the method to be applicable and the sampling of a large number of individuals from catches of commercial fisheries is feasible.
The project GenoPopTaille will first apply RAD sequencing technics to evaluate the genetic structure and gene flow in thornback ray populations from the northeast Atlantic based upon several thousand of SNP (Single Nucleotide Polymorphism) tags. The most informative SNPs for the Bay of Biscay population will then be chosen to be genotyped for a large sample (~7000) of adults and juveniles for a large number (~200) of SNPs. These genetic data will be used to identify parent-offspring pairs. The number of parent-offspring pairs will be used in a population dynamics model for estimating the abundance of spawners, accounting for factors such as individual fecundity and mortality. The feasability of using other parental links (e.g. sibs and half-sibs) for estimating population size will also be evaluated. Further, the use of stranded egg capsules to genetically monitor the abundance of ray populations will be tested using capsules collected by an on-going participative science programme along the French coast.
The challenges taken up by this project are first of all statistical (development population dynamics models and parameter estimation) but also the novel application of genetic tools. The project includes a cost-benefit analysis to evaluate the applicability of the method to other fish populations, in particular declining or endangered species, for which population abundance cannot easily be estimated using other methods.
Keywords
Genomic;
Genetic;
Population dynamic;
Ray;
Marine Region
12
Bay of Biscay North (27.VIIIa)
15
Bay of Biscay Central (27.VIIIb)
2
Marine Region Map
