ホソメコンブに見られる植食性小型巻貝4種による摂餌痕跡(Feeding Traces on the Kelp Laminaria religiosa by Four Species of Small Herbivorous Gastropods)
- 標題
- ホソメコンブに見られる植食性小型巻貝4種による摂餌痕跡(Feeding Traces on the Kelp Laminaria religiosa by Four Species of Small Herbivorous Gastropods)
- 作者
- 中田 和義, 山崎 友資, 水田 浩之, 川井 唯史, 伊藤 博, 五嶋 聖治(Kazuyoshi NAKATA, Tomoyasu YAMAZAKI, Hiroyuki MIZUTA, Tadashi KAWAI, Hiroshi ITO, Seiji GOSHIMA)
- 文件屬性
- 日本研究
- 知識分類
- 水產養殖
- 出版年
- 2006
- 刊名
- 水産増殖
- 卷
- 54
- 期
- 2
- 頁
- P 217-224
- 點閱數
- 4729
摘要
北海道南西部の日本海沿岸で見られる藻場の消失に, 植食性小型巻貝類が及ぼす影響について調べる上で必要となる基礎的知見を得ることを目的に, 研究を実施した。まず, 小型巻貝4種 (クボガイ, コシダカガンガラ, エゾサンショウ, クロタマキビ) によるホソメコンブに対する摂餌痕跡を室内実験で観察した。スチロール樹脂製容器とスライドグラスに着生させたホソメコンブの配偶体をこれら4種の巻貝に摂餌させたところ, すべての巻貝種で配偶体の摂餌が継続的に確認され, 巻貝種間で特徴の異なる摂餌痕跡が観察された。この摂餌痕跡の種間差は, 歯舌の形態と大きさや摂餌様式が巻貝種間で異なることが影響したと考えられた。次に, 野外で採集したホソメコンブの胞子体を観察したところ, 小型巻貝による歯舌の痕跡と思われる形跡が多数観察された。以上から, 植食性小型巻貝がホソメコンブ群落に何らかの影響を与える可能性が示唆された。
To clarify the effects of small herbivorous gastropods on the kelp Laminaria religiosa, we examined feeding traces left on the kelp by gastropods, and the morphology of gastropod radula. We conducted laboratory experiments with four species of the small herbivorous gastropods, Chlorostoma lischkei, Omphalius rusticus rusticus, Homalopoma amussitatum and Littorina sitkana, which frequently occur in habitats of L. religiosa in Hokkaido, Japan, to examine feeding traces left on a sheet of kelp gametophytes settled on styrene chambers or glass slides. In the experiments, all gastropod species fed on the kelp gametophytes both on the styrene chamber and the glass slide. We observed species-specific differences in feeding traces among gastropod species that were considered to be because of differences in the species-specific morphology and size of their radula and differences in feeding patterns. We observed similar traces in adult L. religiosa collected from its natural habitat in Esashi, Hokkaido, to those in our laboratory experiments, suggesting that the four gastropod species used in this study feed on the surface of the adult kelp.
To clarify the effects of small herbivorous gastropods on the kelp Laminaria religiosa, we examined feeding traces left on the kelp by gastropods, and the morphology of gastropod radula. We conducted laboratory experiments with four species of the small herbivorous gastropods, Chlorostoma lischkei, Omphalius rusticus rusticus, Homalopoma amussitatum and Littorina sitkana, which frequently occur in habitats of L. religiosa in Hokkaido, Japan, to examine feeding traces left on a sheet of kelp gametophytes settled on styrene chambers or glass slides. In the experiments, all gastropod species fed on the kelp gametophytes both on the styrene chamber and the glass slide. We observed species-specific differences in feeding traces among gastropod species that were considered to be because of differences in the species-specific morphology and size of their radula and differences in feeding patterns. We observed similar traces in adult L. religiosa collected from its natural habitat in Esashi, Hokkaido, to those in our laboratory experiments, suggesting that the four gastropod species used in this study feed on the surface of the adult kelp.