Diel vertical movements, and effects of infection by the cestode Schistocephalus solidus on daytime proximity of three-spined sticklebacks Gasterosteus aculeatus to the surface of a large Alaskan lake

Abstract

We conducted a field study in Iliamna Lake, Alaska, to test the hypothesis that proximity of three-spined sticklebacks Gasterosteus aculeatus to the lake's surface during the daytime varies with macroparasitic cestode parasite Schistocephalus solidus infection in a manner consistent with enhanced vulnerability to avian predators. Extensive sampling in the lake and likelihood-based modeling revealed that sticklebacks displayed a diel vertical migration, being closer to the surface at night than during the evening and early morning. Additional sampling, also coupled with a likelihood-based modeling approach, showed that fish caught at the surface of the lake during the day were more often parasitized (76 vs. 65%), more heavily parasitized (26.8 vs. 22.7% of their body mass), and had larger individual parasites (0.24 vs. 0.20 g) than those caught at night. Parasite infection was related, non-linearly, to fish size, which also differed between day and night sampling at the surface. We performed statistical competitions among nested hierarchies of models that accounted for this effect of length. The most likely models indicated that fish captured during the day had greater parasite prevalence, higher parasite burdens, and larger parasites than did fish captured at night. Proximity to the surface during the day in this very clear lake would likely increase the vulnerability of sticklebacks to predation from birds, enabling completion of the parasite's lifecycle.

Can the behaviour of threespine stickleback parasitized with Schistocephalus solidus be replicated by manipulating host physiology?

“…They also recover more quickly after a frightening stimulus and forage at a higher rate, even under the risk of predation (Milinski, 1985;Giles, 1987;Godin and Sproul, 1988;Tierney et al, 1993;Ness and Foster, 1999). Moreover, S. solidus-infected sticklebacks spend more time near the water surface, being overrepresented in surface trawls (Quinn et al, 2012). These behavioural modifications (Table 1) in the intermediate fish host can be used to test predictions that stem from each hypothesis about their cause (host response, side effect or direct manipulation).…”

Spatial and temporal patterns of vertical distribution for three planktivorous fishes in Lake Washington

“…There is less information on DVM by three‐spine sticklebacks than by sockeye salmon, but DVM was reported in the Baltic Sea by Jurvelius et al. (1996) and Iliamna Lake, Alaska, by Quinn et al. (2012).…”

“…There is less information on DVM by three-spine sticklebacks than by sockeye salmon, but DVM was reported in the Baltic Sea by Jurvelius et al (1996) and Iliamna Lake, Alaska, by Quinn et al (2012). In Alaska, significant numbers of sticklebacks were caught at the surface during the day, and their vertical shift in distribution was relatively subtle.…”

Diel vertical migration of freshwater fishes – proximate triggers, ultimate causes and research perspectives

“…Infection by cestodes increased the proximity of three‐spined sticklebacks ( Gasterosteus aculeatus L.) to the surface of a lake during daytime, whereas most of uninfected fish performed DVM. The modified DVM patterns of infected fish thus increased the vulnerability to predation by birds, enabling the completion of the parasite’s life cycle (Quinn et al. , 2012).…”