Avian blood parasites in an endangered columbid:Leucocytozoon marchouxiin the Mauritian Pink PigeonColumba mayeri

Abstract

There is increasing evidence that pathogens can play a significant role in species decline. This study of a complete freeliving species reveals a cost of blood parasitism to an endangered host, the Pink Pigeon Columba mayeri, endemic to Mauritius. We investigated the prevalence and effect of infection of the blood parasite, Leucocytozoon marchouxi, in the free-living Pink Pigeon population. Overall, L. marchouxi infection prevalence detected was 18 . 3%. Juveniles were more likely to be infected than older birds and there was geographical variation in infection prevalence. Survival of birds infected with L. marchouxi was lower than that of uninfected birds to 90 days post-sampling. This study suggests that while common haematozoa are well tolerated in healthy adults, these parasites may have greater pathogenic potential in susceptible juveniles. The study is unusual given its completeness of species sampling (96 %) within a short time-period, the accurate host age data, and its focus on blood parasites in a threatened bird species. Species for which long-term life-history data are available for every individual serve as valuable models for dissecting the contribution of particular pathogens to species decline.

Unravelling causality from correlations: revealing the impacts of endemic ectoparasites on a protected species (tuatara)

“…Few studies of threatened species can explore the effects of endemic parasites through experimental manipulation, thus most are limited to observational datasets to infer the costs of parasites to hosts (Valera et al 2006 ;Bunbury et al 2007Bunbury et al , 2008Zhang et al 2008). Since threatened species are often subjected to numerous sources of stress (Lafferty and Kuris, 1999), negative correlations between infection and body condition could have other causes.…”

Leucocytozoonosis

“…A subsequent study of the same population of Pink Pigeons was conducted in 2003 (Bunbury et al 2007). Pigeons less than 1 year of age had higher prevalences of infection with L. marchouxi (∼45%) compared to older birds (∼10-20%).…”

High prevalence of Leucocytozoon parasites in fresh water breeding gulls

“…Leucocytozoon is a genus that infects numerous species of avian hosts, including the domestic chicken, pigeons, owls and many passerine species (Valkiūnas 2005;Bunbury et al 2007;Ishak et al 2008;Dezfoulian et al 2013;Zhao et al 2014). The parasites have a complex life cycle by having merogony in fixed tissues of vertebrate hosts, sexually differentiated gametocytes in blood cells, and sporogony in simuliid flies or Culicoides midges (Valkiūnas 2005).…”