Responsibilities

• Ph.D. student supervised by Prof. Dr. Pablo E. Penchaszadeh, Dr. Marcela Pascual, Prof. Dr. Wolf E. Arntz, Prof. Dr. Sigrid Schiel and Dr. Jürgen Laudien.

Research Interest

• Ecology, genetics and reproduction of Donax and Mesodesma
• Comparative ecosystem research
• Ecology of upwelling areas

Abstract

• Population dynamics, feeding ecology, and larval biology of the surf clam, Donax hanleyanus.
• Exposed intertidal sandy beaches are often dominated by bivalves of the family Donacidae (super family Tellinacea), constituted by the genera Donax, Egeria and Iphigeni. On a worldwide basis, Donacidae form by far the largest group inhabiting such highly dynamic environments. The surf clam Donax hanleyanus, also known as “berberecho”, can be found along the Atlantic coast of South America, from Rio de Janeiro (Brazil) to northern Argentina. Along the coast of the Buenos Aires Province (Argentina), D. hanleyanus is abundant from San Clemente to Punta Mogotes, south of Mar del Plata. The beaches represent the southernmost habitats of a Donax species in the south western Atlantic. D. hanleyanus has a maximum adult size of 42 mm and rarely lives longer than 3 years. In order to study the gametogenic cycle, recruitment patterns, growth, production, and mortality, monthly sampling has been and will continuously be carried out in Santa Teresita, Villa Gesell and Faro Querandi. Growth analyses based on cohort analysis are presently carried out. For microgrowth analysis fluorescent stains (Alizarine, Calcein, Strontium chloride) will be used. To estimate the economically optimal bivalve and food densities in aquaculture systems, nutrition experiments with the algae Isochrysis galbana, Chaetoceros sp. and Tetraselmis sp. are currently carried out. For the observation of the embryonic and larval development under controlled conditions, induction of spawning is necessary by thermal shocks and injection of Serotonin.

Keywords

• Donax hanleyanus, berberecho, population dynamics, feeding ecology, larval biology, aquaculture, spawning, stimulation, Serotonin, fluorescent stains