Data/hora: 01/06/2024 02:43:20

Provedor de dados: | Ocean Docs: e-repository of  publications
País: | Belgium

Título:

Patrones de utilización de la laguna Mar Chiquita (Buenos Aires, Argentina) y área costera adyacente por parte de los primeros estadios ontogénicos de peces

Patterns of use of the Mar Chiquita lagoon (Buenos Aires, Argentina) and adjacent coastal area by fish early life stages

Autores: | Bruno, Daniel O.
Data: | 2014-12-19
Ano: | 2014
Palavras-chave: | Brackishwater fish; Fish larvae; Juveniles; Recruitment; Life cycle; Environmental factors; Abundance; Brackishwater environment; Coastal lagoons; Brevoortia aurea; Gobiosoma parri; Platanichthys platana; Ramnogaster arcuata; Odontesthes argentinensis; Engraulidae; Brackishwater environment.
Resumo: | The role of the Mar Chiquita lagoon and its adjacent coastal area as nursery ground for fish larvae and juveniles and the factors which regulate their recruitment process, was evaluated. To do so, we analyzed the fish early life stages composition and spatio-temporal variation over the marine-estuarine gradient of the lagoon and its relationship with environmental factors; the diel variation of these stages in the immediate area at the mouth of the lagoon; and the source of the organic carbon which feed them on the mouth of the lagoon and adjacent coastal area, by using stable isotope analysis. The richness and mean density of larvae were higher at the offshore area than at the lagoon. Inside the lagoon the dominant species in larval stage was Brevoortia aurea, while in the offshore zone Gobiosoma parri and the Engraulidae Family were dominant. The composition of juvenile stages showed a temporal variation, being Platanichthys platana, Ramnogaster arcuata and Odontesthes argentinensis the first to colonize the lagoon. Although possibly the first two species are represented by both juveniles and adults stages. The low values of abundance and diversity collected at the surf zone suggest that this environment is only used as a transient route between the sea and the lagoon. The highest abundances of both stages were associated with onshore winds, whilst there was no clear pattern in relation to tides. Variations in the composition of fish between light and dark periods were evident, with higher abundances during the first hours of the night, coinciding with the decline of the seabreeze phenomenon. According to isotopic labels, the main source of organic matter that supports larval and juvenile fish outside the lagoon is the macro-detritus derived from terrestrial and marsh plants present in the lagoon. Similar ~d15N values between larval and juvenile fishes suggest that both stages share the resource of food. Finally, we propose a conceptual framework to the lagoon recruitment mediated by environmental factors which rule the entry and exit of water and also discussed the role of small lagoons in the life histories of coastal fishes.
Tipo: | Theses and Dissertations
Idioma: | Espanhol
Identificador: | http://hdl.handle.net/1834/5819

Editor:

Facultad de Ciencias Exactas y Naturales

Mar del Plata (Argentina)

Formato: | 198
Fonte: | http://creativecommons.org/licenses/by-nc/3.0/