Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia

In the 1980s, the Pacific oyster Magallana gigas (Thunberg, 1783) was deliberately introduced in the southern region of the Province of Buenos Aires (Bahía Anegada, BA), Argentina. In 2004, its presence expanded 80 km south of the Río Negro estuary along the coast of El Cóndor (EC). Although oyster...

Full description

Saved in:
Bibliographic Details
Main Authors: Leandro A. Hünicken, Raúl González, Dennis Landete, Maité A. Barrena, Juan F. Saad, Maite A. Narvarte
Format: Article
Language:English
Published: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP) 2025-01-01
Series:Marine and Fishery Sciences
Subjects:
Online Access:https://ojs.inidep.edu.ar/index.php/mafis/article/view/323
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841536602502856704
author Leandro A. Hünicken
Raúl González
Dennis Landete
Maité A. Barrena
Juan F. Saad
Maite A. Narvarte
author_facet Leandro A. Hünicken
Raúl González
Dennis Landete
Maité A. Barrena
Juan F. Saad
Maite A. Narvarte
author_sort Leandro A. Hünicken
collection DOAJ
description In the 1980s, the Pacific oyster Magallana gigas (Thunberg, 1783) was deliberately introduced in the southern region of the Province of Buenos Aires (Bahía Anegada, BA), Argentina. In 2004, its presence expanded 80 km south of the Río Negro estuary along the coast of El Cóndor (EC). Although oysters have demonstrated dispersal capability, there is limited data as regards the EC population since 2011. This research focusses on the present M. gigas population encompassing distribution, abundance, and size structure along a 180-km coastal line from EC to San Antonio Este (SAE). Subsequently, we compared these data with those for the BA population. The presence of M. gigas in the Province of Río Negro was detected in four sites: three of them near the Río Negro estuary (EC, Piedras Verdes PV, and El Pescadero); and the last one in San Antonio Bay. Estimated average abundances near the estuary were lower (range 1.8 10-3 ± 0.6 10-3 and 9 10-2 ± 3.4 10-2 ind. m-2) than BA (105 ± 2 ind. m-2). Presence in SAE was only limited to one site and three adults M. gigas. The BA oyster population exhibited a multimodal distribution, with a significant number of recruits, whereas the PV site displayed a trimodal structure dominated by large specimens. In EC, owing to the limited number of individuals, modal components were less discernible, but small oysters predominated. The current abundance of M. gigas in EC was considerably lower than that in 2011, indicating a population decline. Despite this, the presence of juvenile oysters suggests recent recruitment, emphasizing species resilience. These results show that M. gigas faces challenges when attempting to establish itself in this specific region. Studying the underlying causes would help to understand the factors that limit the expansion of a species considered to be a global invader.
format Article
id doaj-art-e8372a2439eb466e9a6131112b403750
institution Kabale University
issn 2683-7951
language English
publishDate 2025-01-01
publisher Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP)
record_format Article
series Marine and Fishery Sciences
spelling doaj-art-e8372a2439eb466e9a6131112b4037502025-01-14T14:46:48ZengInstituto Nacional de Investigación y Desarrollo Pesquero (INIDEP)Marine and Fishery Sciences2683-79512025-01-0138210.47193/mafis.3822025010105Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern PatagoniaLeandro A. Hünicken0Raúl González1Dennis Landete2Maité A. Barrena3Juan F. Saad4Maite A. Narvarte5Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, ArgentinaCentro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, Argentina - Escuela Superior de Ciencias Marinas, Universidad Nacional del Comahue, San Martín 224, R8520BNF - San Antonio Oeste, ArgentinaCentro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, ArgentinaCentro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, Argentina - Escuela Superior de Ciencias Marinas, Universidad Nacional del Comahue, San Martín 224, R8520BNF - San Antonio Oeste, ArgentinaCentro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, Argentina - Escuela Superior de Ciencias Marinas, Universidad Nacional del Comahue, San Martín 224, R8520BNF - San Antonio Oeste, ArgentinaCentro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos “Almirante Storni”, Güemes 1030, R8520CXV - San Antonio Oeste, Argentina - Escuela Superior de Ciencias Marinas, Universidad Nacional del Comahue, San Martín 224, R8520BNF - San Antonio Oeste, Argentina In the 1980s, the Pacific oyster Magallana gigas (Thunberg, 1783) was deliberately introduced in the southern region of the Province of Buenos Aires (Bahía Anegada, BA), Argentina. In 2004, its presence expanded 80 km south of the Río Negro estuary along the coast of El Cóndor (EC). Although oysters have demonstrated dispersal capability, there is limited data as regards the EC population since 2011. This research focusses on the present M. gigas population encompassing distribution, abundance, and size structure along a 180-km coastal line from EC to San Antonio Este (SAE). Subsequently, we compared these data with those for the BA population. The presence of M. gigas in the Province of Río Negro was detected in four sites: three of them near the Río Negro estuary (EC, Piedras Verdes PV, and El Pescadero); and the last one in San Antonio Bay. Estimated average abundances near the estuary were lower (range 1.8 10-3 ± 0.6 10-3 and 9 10-2 ± 3.4 10-2 ind. m-2) than BA (105 ± 2 ind. m-2). Presence in SAE was only limited to one site and three adults M. gigas. The BA oyster population exhibited a multimodal distribution, with a significant number of recruits, whereas the PV site displayed a trimodal structure dominated by large specimens. In EC, owing to the limited number of individuals, modal components were less discernible, but small oysters predominated. The current abundance of M. gigas in EC was considerably lower than that in 2011, indicating a population decline. Despite this, the presence of juvenile oysters suggests recent recruitment, emphasizing species resilience. These results show that M. gigas faces challenges when attempting to establish itself in this specific region. Studying the underlying causes would help to understand the factors that limit the expansion of a species considered to be a global invader. https://ojs.inidep.edu.ar/index.php/mafis/article/view/323Invasive speciespopulation dynamicsintertidalecosystem engineerrecruitment
spellingShingle Leandro A. Hünicken
Raúl González
Dennis Landete
Maité A. Barrena
Juan F. Saad
Maite A. Narvarte
Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
Marine and Fishery Sciences
Invasive species
population dynamics
intertidal
ecosystem engineer
recruitment
title Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
title_full Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
title_fullStr Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
title_full_unstemmed Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
title_short Distribution, abundance, and size structure of the Pacific cupped oyster Magallana gigas in northern Patagonia
title_sort distribution abundance and size structure of the pacific cupped oyster magallana gigas in northern patagonia
topic Invasive species
population dynamics
intertidal
ecosystem engineer
recruitment
url https://ojs.inidep.edu.ar/index.php/mafis/article/view/323
work_keys_str_mv AT leandroahunicken distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia
AT raulgonzalez distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia
AT dennislandete distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia
AT maiteabarrena distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia
AT juanfsaad distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia
AT maiteanarvarte distributionabundanceandsizestructureofthepacificcuppedoystermagallanagigasinnorthernpatagonia