Temperature dependent larval occurrence and spat settlement of the invasive brackish water bivalve Mytilopsis leucophaeata (Conrad, 1831) (Dreissenidae) |
| |
| Institution: | 1. Radboud University Nijmegen, Institute for Water and Wetland Research, Department of Animal Ecology and Ecophysiology, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands;2. Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands;3. Royal Netherlands Institute for Sea Research NIOZ, Korringaweg 7, 4401 NT Yerseke, The Netherlands;1. Mohammed V-Agdal University, LRIT Associated Unit to the CNRST-URAC no. 29, Rabat, Morocco;2. INRIA Bordeaux Sud-Ouest (GEOSTAT Team), Talence, France;3. Royal Centre for Remote Sensing (CRTS), Rabat, Morocco |
| |
| Abstract: | Mytilopsis leucophaeata, an invasive bivalve species, causes fouling problems by settling on submerged constructions and in cooling water circuits in brackish water. To predict spat fall we studied the larval occurrence and settlement of this species in the brackish Noordzeekanaal canal in the Netherlands for several years (1989–1992), while measuring water temperature, salinity and chlorophyll a levels. Larvae were collected monthly by means of a plankton net drawn across the whole width of the canal. Settled spat were collected from PVC panels exposed for one month. Larvae first appeared in May or June, and reached maximum numbers in June or July, before disappearing in October, November or even December. The larval period started at a water temperature of 14 °C, reached maximum numbers at 19–23 °C and ended when it fell below 9 °C. No larvae were observed anymore until the temperature rose to 14 °C in the spring of the next year. Spat fall (June–November) was related to the water temperature in April. If the water temperature in April was lower than 12.5 °C, spat fall started in July, while if temperature was already higher in April, it started a month earlier. The spat fall period started at 15 °C, with maximum numbers at 20–24 °C, and ended when the water temperature dropped below 5 °C. Redundancy analysis (RDA) demonstrated a strong relationship between larval and spat densities and water temperature. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
