Most cited article - PubMed ID 30352825
Altered thermoregulation as a driver of host behaviour in glochidia-parasitised fish
Parasites can change the behaviour of their hosts, but little attention has been given to the relationship between parasite effects on host behaviour and colouration. The correlation between disrupted melanin production and alterations in various physiological and behavioural traits, e.g., aggression, shoaling behaviour, stress responsiveness and sensitivity to brood parasitism, has been reported in albino fish. We hypothesized that parasitism would affect the behaviour of albino and pigmented conspecifics differently. In laboratory conditions, we infested a group of pigmented and a group of albino individuals of European catfish Silurus glanis with glochidia of two Uninoidea species, namely, the native species Anodonta anatina and the invasive species Sinanodonta woodiana, and investigated the effect of parasitization on the boldness and sheltering behaviour of the hosts. The behaviour of albino individuals differed from that of pigmented conspecifics both before and after parasitization. Parasitization with glochidia did not affect sheltering behaviour, but it increased boldness in pigmented individuals, whereas albino individuals did not exhibit any changes in behaviour. Sheltering results were consistent in both binomial and continuous variable analyses, whereas boldness was significant only in the binomial analyses. Our results demonstrate the reduced susceptibility of the albino phenotype to glochidia infestation, together with questions of the choice of analyses.
A simple and low-cost method of monitoring and collecting particulate matter detaching from (or interacting with) aquatic animals is described using a novel device based on an airlift pump principle applied to floating cages. The efficiency of the technique in particle collection is demonstrated using polyethylene microspheres interacting with a cyprinid fish (Carassius carassius) and a temporarily parasitic stage (glochidia) of an endangered freshwater mussel (Margaritifera margaritifera) dropping from experimentally infested host fish (Salmo trutta). The technique enables the monitoring of temporal dynamics of particle detachment and their continuous collection both in the laboratory and in situ, allowing the experimental animals to be kept under natural water quality regimes and reducing the need for handling and transport. The technique can improve the representativeness of current experimental methods used in the fields of environmental parasitology, animal feeding ecology and microplastic pathway studies in aquatic environments. In particular, it makes it accessible to study the physiological compatibility of glochidia and their hosts, which is an essential but understudied autecological feature in mussel conservation programs worldwide. Field placement of the technique can also aid in outreach programs with pay-offs in the increase of scientific literacy of citizens concerning neglected issues such as the importance of fish hosts for the conservation of freshwater mussels.
- Keywords
- Aquatic animals, drop-off, fish, freshwater mussels, glochidia, host–parasite relationships, microparticles, microplastics,
- Publication type
- Journal Article MeSH
