| 要旨トップ | 目次 | 日本生態学会第70回全国大会 (2023年3月、仙台) 講演要旨
ESJ70 Abstract


一般講演(ポスター発表) P2-019  (Poster presentation)

サケ科魚類に寄生する寄生虫3種の共感染パターンの解明:宿主への影響と地理的分布【B】【E】
Elucidating the coinfection patterns of three species of parasites infecting stream salmonid: effects on host condition and geographic distribution【B】【E】

*長谷川稜太(北海道大学環境科学院), 植村洋亮(北海道大学環境科学院), 三浦一輝(北海道立総合研究機構), 小泉逸郎(北海道大学環境科学院)
*Ryota HASEGAWA(Hokkaido Univ.), Yohsuke UEMURA(Hokkaido Univ.), Kazuki MIURA(Hokkaido Research Organization), Itsuro KOIZUMI(Hokkaido Univ.)

Organisms are frequently infected with multiple parasite species. Such coinfecting parasites interact with each other, and these interactions could affect impacts on host fitness and parasite geographic distribution, but field evidence is still limited. Here, we examined a wide-range geographic distribution pattern of three species of ectoparasites (gill infecting freshwater pearl mussel FPM, gill infecting copepod S. edwardsii, mouth infecting copepod Salmincola cf. markewitschi) infecting congeneric stream salmonids (white-spotted charr WSC and Dolly Varden DV). We specifically hypothesized that (1) induced host immunity by FPM infections reduces infection levels of Salmincola spp., (2) host body condition would be strongly reduced when coinfection occur. We captured fish by electrofishing at 75 sites in eastern Hokkaido. Contrary to our initial predictions, FPM were likely to co-occur with Salmincola spp., resulting in higher frequencies of coinfections. Host body condition decreased with S. cf. markewitschi infections, but the effects became larger when coinfected with FPM, especially under higher water temperature. Our results indicate that the costs of coinfections were larger than the infections by a single parasite, and its impacts depend on ambient environments.


日本生態学会