Hatchery-produced sandfish (Holothuria scabra) show altered genetic diversity in New Caledonia

Type Article
Date 2022-08
Language English
Author(s) Riquet FlorentineORCID1, 2, Fauvelot Cécile1, 2, Fey Pauline1, Grulois Daphné1, Leopold Marc1, 3
Affiliation(s) 1 : UMR ENTROPIE (IRD, University of La Reunion, CNRS, University of New Caledonia, Ifremer), 98800 Noumea, New Caledonia
2 : UMR LOV (Sorbonne University, CNRS), 06230 Villefranche-sur-Mer, France
3 : UMR ENTROPIE (IRD, University of La Reunion, CNRS, University of New Caledonia, Ifremer), 97400 Saint-Denis, La Reunion c/o IUEM, 29280 Plouzané, france
Source Fisheries Research (0165-7836) (Elsevier BV), 2022-08 , Vol. 252 , P. 106343 (10p.)
DOI 10.1016/j.fishres.2022.106343
WOS© Times Cited 4
Keyword(s) Genetic outcome, Reseeding, Stock structure, Sea cucumber, Sustainable fishery
Abstract

Facing an alarming continuing decline of wild sea cucumber resources, management strategies were developed over the past three decades to sustainably promote development, maintenance, or regeneration of wild sea cucumber fisheries. In New Caledonia (South Pacific), dedicated management efforts via restocking and sea ranching programs were implemented to cope with the overharvesting of the sandfish Holothuria scabra and the recent loss of known populations. In order to investigate genetic implications of a major H. scabra restocking program, we assessed the genetic diversity and structure of wild stocks and hatchery-produced sandfish and compared the genetic outcomes of consecutive spawning and juvenile production events. For this, 1,358 sandfish collected at four sites along the northwestern coasts of New Caledonia, as well as during five different restocking events in the Tiabet Bay, were genotyped using nine polymorphic microsatellite markers. We found that wild H. scabra populations from the northwestern coast of New Caledonia likely belonged to one panmictic population with high level of gene flow observed along the study scale. Further, this panmictic population displayed an effective size of breeders large enough to ensure the feasibility of appropriate breeding programs for restocking. In contrast, hatchery-produced samples did suffer from an important reduction in the effective population size: the effective population sizes were so small that genetic drift was detectable over one generation, with the presence of inbred individuals, as well as more related dyads than in wild populations. All these results suggest that dedicated efforts in hatcheries are further needed to maintain genetic diversity of hatchery-produced individuals in order to unbalance any negative impact during this artificial selection.

Full Text
File Pages Size Access
10 1 MB Access on demand
Author's final draft 25 940 KB Open access
Top of the page