Search results for "tiaiset"

Competition between strains of Borrelia afzelii inside the rodent host and the tick vector

2018

Multiple-strain pathogens often establish mixed infections inside the host that result in competition between strains. In vector-borne pathogens, the competitive ability of strains must be measured in both the vertebrate host and the arthropod vector to understand the outcome of competition. Such studies could reveal the existence of trade-offs in competitive ability between different host types. We used the tick-borne bacteriumBorrelia afzeliito test for competition between strains in the rodent host and the tick vector, and to test for a trade-off in competitive ability between these two host types. Mice were infected via tick bite with either one or two strains, and these mice were subse…

Sympatric Ixodes-tick species: pattern of distribution and pathogen transmission within wild rodent populations

2018

AbstractThe generalist tick Ixodes ricinus is the most important vector for tick-borne pathogens (TBP), including Borrelia burgdorferi sensu lato, in Europe. However, the involvement of other sympatric Ixodes ticks, such as the specialist vole tick I. trianguliceps, in the enzootic circulations of TBP remains unclear. We studied the distribution of I. ricinus and I. trianguliceps in Central Finland and estimated the TBP infection likelihood in the most common rodent host in relation with the abundance of the two tick species. Ixodes trianguliceps was encountered in all 16 study sites whereas I. ricinus was frequently observed only at a quarter of the study sites. The abundance of I. ricinus…

Monitoring of ticks and tick-borne pathogens through a nationwide research station network in Finland.

2020

In 2015 a long-term, nationwide tick and tick-borne pathogen (TBP) monitoring project was started by the Finnish Tick Project and the Finnish Research Station network (RESTAT), with the goal of producing temporally and geographically extensive data regarding exophilic ticks in Finland. In the current study, we present results from the first four years of this collaboration. Ticks were collected by cloth dragging from 11 research stations across Finland in May September 2015-2018 (2012-2018 in Seili). Collected ticks were screened for twelve different pathogens by qPCR: Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, Borrelia burgdorferi sensu stricto, Borrelia miyamotoi, Babesia sp…

Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland

2022

AbstractBackgroundTicks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur:IxodesricinusandIxodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change.MethodsWe used species distribution modelling techniques to predict the distributions ofI.ricinusandI.persulcatus,using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Fin…

Interaction of climate change with effects of conspecific and heterospecific density on reproduction

2020

We studied the relationship between temperature and the coexistence of great tit Parus major and blue tit Cyanistes caeruleus, breeding in 75 study plots across Europe and North Africa. We expected an advance in laying date and a reduction in clutch size during warmer springs as a general response to climate warming and a delay in laying date and a reduction in clutch size during warmer winters due to density-dependent effects. As expected, as spring temperature increases laying date advances and as winter temperature increases clutch size is reduced in both species. Density of great tit affected the relationship between winter temperature and laying date in great and blue tit. Specifically…

Titmice are a better indicator of bird density in Northern European than in Western European forests

2022

Publisher Copyright: © 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. Population sizes of many birds are declining alarmingly and methods for estimating fluctuations in species’ abundances at a large spatial scale are needed. The possibility to derive indicators from the tendency of specific species to co-occur with others has been overlooked. Here, we tested whether the abundance of resident titmice can act as a general ecological indicator of forest bird density in European forests. Titmice species are easily identifiable and have a wide distribution, which makes them potentially useful ecological indicators. Migratory birds often use information on the densit…

Eco-epidemiology of tick- and rodent-borne pathogens in boreal forests

2017

Infectious diseases are amongst the ten major causes of human mortality worldwide, 60% of them being animal-borne. Variations of abiotic and biotic conditions are likely to modify the transmission of parasites and pathogens within reservoir species, and, as a consequence, alter the zoonotic risk for human. My thesis aims at elucidating the dynamics and mechanisms of the maintenance of ticks, tick-borne pathogens (TBPs) and the Puumala hantavirus (PUUV) in the reservoir host, the bank vole (Myodes glareolus, BV). In Northern Europe, tick-borne diseases are growing in importance to human because of the latitudinal expansion of the tick Ixodes ricinus. Field monitoring revealed that I. ricinus…

Seasonality of Ixodes ricinus and Ixodes trianguliceps tick on the bank vole (Myodes glareolus) and on vegetation in Central Finland

2014

Mixed-species flock size affects contact call frequencies of the crested tit, Lophophanes cristatus

2012

Ääntelemällä tapahtuva kommunikointi voi altistaa linnut saalistukselle, koska pedot voivat paikantaa saaliseläimet ääntelyn perusteella. Yksi mahdollinen tapa suojautua saalistajilta on liittyminen parviin. Parveutuminen voi vaikuttaa ääntelyfrekvensseihin lisääntyneen parvensisäisen kommunikointitarpeen kautta, mutta myös koska ääntely suuremmissa parvissa voi olla saalistusriskin suhteen turvallisempaa. Tässä tutkimuksessa tutkin lajienvälisen sekaparven koon vaikutusta töyhtötiaisen pitkän etäisyyden kommunikointiin yleensä, parven sisäiseen kommunikointiin ja parvien väliseen reviirinpuolustuskommunikointiin. Tutkimusmenetelmänä oli töyhtötiaisparvien tarkkailu luonnollisissa olosuhtei…