期刊
MARINE ECOLOGY PROGRESS SERIES
卷 504, 期 -, 页码 287-300出版社
INTER-RESEARCH
DOI: 10.3354/meps10758
关键词
Ontogeny; Critical swimming speed; U-crit; Sardina pilchardus; Nucleic acid derived indices; RNA/DNA; Foraging
资金
- Project VITAL (Vital rates of pelagic fish larvae) [PTDC/MAR/111304/2009]
- Portuguese Foundation for Science and Technology (FCT) [SFRH/BPD/38332/2007, SFRH/BPD/68673/2010]
- European Regional Development Fund (ERDF) through the COMPETE Operational Competitiveness Programme
- FCT [PEst-C/MAR/LA0015/2011]
- Faculty of Sciences of the University of Lisbon
- Oceanario de Lisboa
- University of Algarve
The ontogeny of swimming behaviour in sardine Sardina pilchardus larvae was studied, from hatching to 75 days post-hatch (dph), by measuring the critical swimming speed (U-crit) and observing locomotory behaviour. In addition, the effect of larval nutritional condition on U-crit at the onset of their swimming abilities (20 to 25 dph) was evaluated by rearing larvae under 4 different feeding treatments. Diets consisted of different concentrations of dinoflagellates, rotifers and the copepod Acartia grani, and a wild plankton assemblage. Recently hatched larvae were mostly inactive, but from 2 dph onwards larvae started to swim freely in the rearing tank, and time spent swimming increased throughout ontogeny. Larvae younger than 20 dph (i.e. < 7.90 mm TL) could not swim for the entire adjustment period at the minimum current speed, but thereafter Ucrit increased significantly with larval age and length, reaching a maximum of 9.47 cm s(-1) at 19.10 mm TL and 55 dph. Growth, survival and the nutritional condition of sardine larvae, assessed by the RNA residual index, were significantly higher for larvae reared with the high-concentration diet, contrary to the other derived nucleic acids indices (RNA/DNA and DNA/DW), which showed no differences between diets. Despite differences in the survival and growth rates of sardine larvae, Ucrit at the onset of swimming did not differ significantly among diets, but was significantly related to larval nutritional condition as assessed by the RNA residual index. Overall, our results show that early larval stages of sardines have poor swimming ability and probably rely on food patches in the wild to survive; however, close to metamorphosis (especially from 45 dph onwards), larvae spend most of the time swimming and are capable of resisting the mean current speeds of their natural environment, which may strongly enhance chances for survival.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据