| 英文摘要 |
Jellyfish was relatively diverse in the northeastern waters off Taiwan, particularly in Chinshan and Yehliu waters. In all, ＞20 species and ＞500 specimens of jellyfish were obtained, and shall be a “hot spot”. Aequorea spp and Pelagia noctiluca were the 2 predominant species. While in the western coastal waters, less jellyfish species were found, but occasionally bloomed in warm and dry season, such as Aurelia aurita, Acromitus flagellatus, and Catostylus townsendi; particularly the bloom of C. townsendi in this summer that might decrease ca. 5~30% of fishery catch. As for the cause of jellyfish bloom, climate warming possibly is the main point, but it might be also due to the slower water current, many bays, pollution and over-fishing in this area. The cubomedusa, Carybdea rastoni, usually bloom in Chengon coastal waters in summer and closely related to local climate and water current. The catch of cubomedusa more or less contributes the economic benefit for local fishery when other fishery harvest is lower in summer. In additions, we also focused on a lab experiment to see the influence of temperature and light on the growth of moon-jelly’s polys, and found that polys incubated in 30 ℃ had faster strobilating rate and ephyrae releasing rate, but with higher mortality; while in 20 ℃, the polys showed higher survival rate but had lower growing and releasing rate. Our results suggested that 25 ℃ and dark environment should be the optimal condition for the reproduction of asexual generation. |
