Variation in anti-parasite behaviour and infection among larval amphibian species

Abstract

Along with immune defences, many animals exhibit effective anti-parasite behaviours such as parasite avoidance and removal that influence their susceptibility to infection. Host ecology and life history influence investment into comparatively fixed defences such as innate immunity but may affect the strength of anti-parasite behaviours as well. We investigated activity levels in five different species of larval amphibian with varying life histories and ecology in control, novel food stimulus, and trematode parasite (Echinoparyphium sp.) threat conditions. There was a significant interaction of species and treatment given that American toad (Bufo americanus), wood frog (Lithobates sylvaticus), and bullfrog (Lithobates catesbeianus) tadpoles generally increased their activity when parasite infectious stages were present while grey tree frogs (Hyla versicolor) and northern leopard frogs (Lithobates pipiens) did not, even though activity was negatively related to infection. In addition, there was considerable variation among species in their susceptibility to parasitism, with infection prevalence ranging from 17% in bullfrog tadpoles to 70% in wood frogs. However, amphibian life history (larval and adult traits) was not related to parasitism or level of anti-parasite behaviour at the species level. Consequently, we suggest that future investigations include more species with a range of life history traits and also consider host ecology, particularly if conspicuous anti-parasite behaviours are more likely in amphibian species that experience a relatively low risk of predation.

Host life history and host–parasite syntopy predict behavioural resistance and tolerance of parasites

“…Additionally, a recent study by Koprivnikar, Refern & Mazier (2014) discovered that pace-of-life did not seem to be as strong of a predictor of behavioural resistance to cercariae as host–parasite syntopy. Tadpoles of the American toad ( Bufo americanus ) and wood frog ( Lithobates sylvaticus ), species with low spatiotemporal overlap with cercariae, exhibited much stronger anti-cercarial responses than tadpoles of grey tree frogs ( Hyla versicolor ) and northern leopard frogs ( Lithobates pipiens ), species with high syntopy with cercariae (Koprivnikar, Refern & Mazier 2014). Wood frogs, however, have similar larval periods and size at metamorphosis and thus have a comparable pace-of-life as the grey tree frogs and northern leopard frogs.…”

“…For example, toad tadpoles that have low syntopy with cercariae avoided cercariae (Rohr et al 2009) and a ranid tadpole species with lower host-parasite syntopy exhibited more anticercarial behaviours than a ranid species with higher host-parasite syntopy (Thiemann & Wassersug 2000). Additionally, a recent study by Koprivnikar, Refern & Mazier (2014) discovered that pace-of-life did not seem to be as strong of a predictor of behavioural resistance to cercariae as host-parasite syntopy. Tadpoles of the American toad (Bufo americanus) and wood frog (Lithobates sylvaticus), species with low spatiotemporal overlap with cercariae, exhibited much stronger anti-cercarial responses than tadpoles of grey tree frogs (Hyla versicolor) and northern leopard frogs (Lithobates pipiens), species with high syntopy with cercariae (Koprivnikar, Refern & Mazier 2014).…”

A review of the role of parasites in the ecology of reptiles and amphibians

“…; Koprivnikar et al . ). Permanent pond breeding frogs that were more likely to encounter trematodes ( Echinostoma spp.)…”

Host community composition and defensive symbionts determine trematode parasite abundance in host communities

“…Amphibians have well‐known behavioral (Koprivnikar et al. , , Daly and Johnson ) and immunological (Belden and Kiesecker , Holland , LaFonte and Johnson ) defenses when confronted with cercariae. However, amphibian species vary in their behavioral and immunological responses and thus their susceptibility to echinostome infection (e.g., Koprivnikar et al.…”

“…However, amphibian species vary in their behavioral and immunological responses and thus their susceptibility to echinostome infection (e.g., Koprivnikar et al. ). Snail species also vary in their susceptibility to infection by echinostome cercariae (Christensen et al.…”