title: Use of sibling relationship reconstruction to complement traditional monitoring in fisheries management and conservation of brown trout.
abstract: Declining trends in the abundance of many fish urgently call for more efficient and informative monitoring methods that would provide necessary demographic data for the evaluation of existing conservation, restoration, and management actions. We investigated how genetic sibship reconstruction from young-of-the-year brown trout (Salmo trutta L.) juveniles provides valuable, complementary demographic information that allowed us to disentangle the effects of habitat quality and number of breeders on juvenile density. We studied restored (n = 15) and control (n = 15) spawning and nursery habitats in 16 brown trout rivers and streams over 2 consecutive years to evaluate the effectiveness of habitat restoration activities. Similar juvenile densities both in restored and control spawning and nursery grounds were observed. Similarly, no differences in the effective number of breeders, Nb(SA) , were detected between habitats, indicating that brown trout readily used recently restored spawning grounds. Only a weak relationship between the Nb(SA) and juvenile density was observed, suggesting that multiple factors affect juvenile abundance. In some areas, very low estimates of Nb(SA) were found at sites with high juvenile density, indicating that a small number of breeders can produce a high number of progeny in favorable conditions. In other sites, high Nb(SA) estimates were associated with low juvenile density, suggesting low habitat quality or lack of suitable spawning substrate in relation to available breeders. Based on these results, we recommend the incorporation of genetic sibship reconstruction to ongoing and future fish evaluation and monitoring programs to gain novel insights into local demographic and evolutionary processes relevant for fisheries management, habitat restoration, and conservation.
authors.affiliation: Division of Genetics and Physiology, Department of Biology, University of Turku, 20014, Turku, Finland.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Ozerov
authors.affiliation: Department of Aquaculture, Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, 51014, Tartu, Estonia.
authors.forename: Tauno
authors.initials: T
authors.lastname: Jürgenstein
authors.affiliation: Division of Genetics and Physiology, Department of Biology, University of Turku, 20014, Turku, Finland.
authors.forename: Tutku
authors.initials: T
authors.lastname: Aykanat
authors.affiliation: Division of Genetics and Physiology, Department of Biology, University of Turku, 20014, Turku, Finland.|Department of Aquaculture, Institute of Veterinary Medicine and Animal Science, Estonian University of Life Sciences, 51014, Tartu, Estonia.
authors.forename: Anti
authors.initials: A
authors.lastname: Vasemägi
mesh_terms: D000818:Animals; D003247:Conservation of Natural Resources / Q000379:methods*; D017753:Ecosystem; D004957:Estonia; D005260:Female; D005398:Fisheries / Q000379:methods*; D008297:Male; D011156:Population Density; D012098:Reproduction; D045483:Rivers; D035781:Siblings; D014337:Trout / Q000235:genetics / Q000502:physiology*
keywords: Ne; brown trout; densidad juvenil; designación de número de crías producidos por una pareja de padres; effective number of breeders; effective population size; habitat restoration; juvenile density; número efectivo de reproductores; restauración de hábitat; salmonids; salmónidos; sibship assignment; tamaño efectivo de la población; trucha café