Search results for "BLACKBIRDS"
showing 6 items of 6 documents
Host dispersal shapes the population structure of a tick-borne bacterial pathogen
2020
Birds are hosts for several zoonotic pathogens. Because of their high mobility, especially of longdistance migrants, birds can disperse these pathogens, affecting their distribution and phylogeography. We focused on Borrelia burgdorferi sensu lato, which includes the causative agents of Lyme borreliosis, as an example for tick-borne pathogens, to address the role of birds as propagation hosts of zoonotic agents at a large geographical scale. We collected ticks from passerine birds in 11 European countries. B. burgdorferi s.l. prevalence in Ixodes spp. was 37% and increased with latitude. The fieldfare Turdus pilaris and the blackbird T. merula carried ticks with the highest Borrelia prevale…
Social information use about novel aposematic prey is not influenced by a predator’s previous experience with toxins
2019
Aposematism is an effective antipredator strategy. However, the initial evolution and maintenance of aposematism are paradoxical because conspicuous prey are vulnerable to attack by naive predators. Consequently, the evolution of aposematic signal mimicry is also difficult to explain. The cost of conspicuousness can be reduced if predators learn about novel aposematic prey by observing another predator's response to that same prey. On the other hand, observing positive foraging events might also inform predators about the presence of undefended mimics, accelerating predation on both mimics and their defended models. It is currently unknown, however, how personal and social information combi…
Social transmission in the wild can reduce predation pressure on novel prey signals
2021
Funder: Suomen Kulttuurirahasto (Finnish Cultural Foundation); doi: https://doi.org/10.13039/501100003125
Caution on the assessment of intestinal parasitic load in studying parasite-mediated sexual selection: the case of Blackbirds coccidiosis.
2009
6 pages; International audience; The parasite-mediated sexual selection (PMSS) theory has led to an increasing number of experimental studies essentially focussed on blood parasites. Currently, more research is being carried out on intestinal parasites in relationship to this theory. Before testing the theory with gastrointestinal parasites, it is important: (i) to determine an optimal research methodology to obtain an accurate assessment of parasite burden and (ii) to have information about life-history traits of the parasite to interpret data appropriately. In this study, we present data on oocyst output of Isosporaturdi in the faeces of blackbirds (Turdus merula) that illustrate the impo…
Circadian variation in shedding of the oocysts of Isospora turdi (Apicomplexa) in blackbirds (Turdus merula): an adaptative trait against desiccation…
2009
5 pages; International audience; Many parasite species spend part of their life cycle in the external environment waiting for a new host. Emergence of parasites often occurs once a day, which may help to minimise mortality in an inhospitable environment and increase transition rates. Many intestinal parasites in birds are released in faeces only in the late afternoon. However, the adaptative significance of this pattern is unclear. One hypothesis is that a particular time of emergence may prevent parasite desiccation and therefore increase the parasite's life expectancy in the external environment. We tested this hypothesis experimentally using the blackbird (Turdus merula) infected with Is…
Sex-ratio of Skylark Alauda arvensis broods in relation to timing of breeding.
2006
4 pages; International audience; Capsule Earlier broods tend to be more male biased than later broods.