Growth in a Modular Colonial Marine Invertebrate

• Published in: Estuarine, coastal and shelf science Vol. 47; no. 4; pp. 459 - 470
• Main Authors: Coma, R., Ribes, M., Zabala, M., Gili, J.-M.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01.10.1998; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Demecology; Fundamental and applied biological sciences. Psychology; Gorgonacea; gorgonian; growth rates; Mediterranean Sea; modular colonial growth; Paramuricea clavata; production; production/biomass; Protozoa. Invertebrata; size; turnover time; Mediterranean Sea; West Mediterranean; Europe; Spain; MED, Spain, Gerona, Medes Is; production/biomass; growth rates; size; production; Mediterranean Sea; modular colonial growth; gorgonian; turnover time; Marine environment; Biometrics; Secondary productivity; Growth rate; Seasonal variation; Turnover; Colony; Biomass; Invertebrata; Island; Interannual variation
• ISSN: 0272-7714; 1096-0015
• DOI: 10.1006/ecss.1998.0375

Growth rate, temporal variability and secondary production were quantified for the Mediterranean gorgonianParamuricea clavataoff Medes Islands, NW Mediterranean. Fifty-four colonies ranging in size between 5 and 860cm in total length (3–55cm maximum height) were monitored photographically for 2 years. Growth varied between and within years. Primary branches accounted for 91% of production, though their growth rates were highly variable (on average 23% of branches displayed zero growth). The gross growth rate of primary branches in colonies <20cm was higher (0·8cm year−1) than that of colonies >20cm (0·5cm years−1). On average, net growth of primary branches (0·4cm year−1) was approximately 60% of positive growth. There was a significant size-specific negative growth effect in which smaller colonies displayed higher rates of loss. Mean growth in colony height was 1·8cm year−1(range: 0·2–6·4cm year−1). Based on growth rate data, the largest colonies in the population (55cm) were around 31 years old. On average, net production for all colonies was 75% of gross production. Gross production was 4·4g AFDW m−2year−1, the production/biomass value was 0·11, and the turnover time was 9 years. Growth rate and its variation with colony size are discussed within the framework of the life history traits of the species.