Host community heterogeneity and the expression of host specificity in avian haemosporidia in the Western Cape, South Africa

AbstractSimilar patterns of parasite prevalence in animal communities may be driven by a range of different mechanisms. The influences of host heterogeneity and host–parasite interactions in host community assemblages are poorly understood. We sampled birds at 27 wetlands in South Africa to compare four hypotheses explaining how host community heterogeneity influences host specificity in avian haemosporidia communities: the host-neutral hypothesis, the super-spreader hypothesis, the host specialist hypothesis and the heterogeneity hypothesis. A total of 289 birds (29%) were infected with Plasmodium, Haemoproteus and/or Leucocytozoon lineages. Leucocytozoon was the most diverse and generalist parasite genus, and Plasmodium the most conservative. The host-neutral and host specialist hypotheses received the most support in explaining prevalence by lineage (Leucocytozoon) and genus (Plasmodium and Haemoproteus), respectively. We observed that haemosporidian prevalence was potentially amplified or reduced with variation in host and/or parasitic taxonomic levels of analysis. Our results show that Leucocytozoon host abundance and diversity was influential to parasite prevalence at varying taxonomic levels, particularly within heterogeneous host communities. Furthermore, we note that prevalent mechanisms of infection can potentially act as distinct roots for shaping communities of avian haemosporidia.

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Host-parasite interaction explains variation in prevalence of avian haemosporidians at the community level

10.1101/432260 ◽

2018 ◽

Author(s):

L. Garcia-Longoria ◽

A. Marzal ◽

F. de Lope ◽

L. Z. Garamszegi

Keyword(s):

Host Species ◽

Bird Species ◽

Ecological Factors ◽

Bird Community ◽

Parasite Prevalence ◽

Host Community ◽

Dual Nature ◽

Host Parasite Interactions ◽

Avian Haemosporidians ◽

Host Parasite

ABSTRACTParasites are a selective force that shape host community structure and dynamics, but host communities can also influence parasitism. Understanding the dual nature from host-parasite interactions can be facilitated by quantifying the variation in parasite prevalence (i.e. the proportion of infected host individuals in a population) among host species and then comparing that variation to other ecological factors that are known to also shape host communities. Avian haemosporidian parasites (e.g. Plasmodium and Haemoproteus) are abundant and widespread representing an excellent model for the study of host-parasite interactions. Several geographic and environmental factors have been suggested to determine prevalence of avian haemosporidians in bird communities. However, much remains to be known regarding whether host and parasite traits, represented by phylogenetic distances among species and degree of specialization in host-parasite relationships, can influence parasite prevalence. The aims of this study were to analyze factors affecting prevalence in a bird community and to test whether the degree of parasite specialization on their hosts is determined by host traits. Our statistical analyses suggest that prevalence is mainly determined by the interaction between host species and parasite lineages where tolerance and/or susceptibility to parasites plays an essential role. Additionally, we found that although some of the parasite lineages infected a low number of bird species, the species they infected were distantly related and therefore the parasites themselves should not be considered typical host specialists. Prevalence was higher for generalist than for specialist parasites in some, but not all, host species. These results suggest that prevalence mainly results from the interaction between host immune defences and parasite exploitation strategies wherein the result of an association between particular parasite lineages and particular host species is idiosyncratic.

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Analysis of large new South African dataset using two host-specificity indices shows generalism in both adult and larval ticks of mammals

Parasitology ◽

10.1017/s0031182015001730 ◽

2015 ◽

Vol 143 (3) ◽

pp. 366-373 ◽

Cited By ~ 9

Author(s):

MARCELA P. A. ESPINAZE ◽

ELÉONORE HELLARD ◽

IVAN G. HORAK ◽

GRAEME S. CUMMING

Keyword(s):

Host Specificity ◽

South African ◽

New South ◽

Life Stage ◽

Host Preferences ◽

Infestation Intensity ◽

Host Parasite Interactions ◽

Host Phylogeny ◽

Pathogen Control ◽

Host Parasite

SUMMARYTicks and tick-borne pathogens can have considerable impacts on the health of livestock, wildlife and people. Knowledge of tick–host preferences is necessary for both tick and pathogen control. Ticks were historically considered as specialist parasites, but the range of sampled host species has been limited, infestation intensity has not been included in prior analyses, and phylogenetic distances between hosts have not been previously considered. We used a large dataset of 35 604 individual collections and two host-specificity indices to assess the specificity of 61 South African tick species, as well as distinctions between adult and juvenile ticks, for 95 mammalian hosts. When accounting for host phylogeny, most adult and juvenile ticks behaved as generalists, with juveniles being significantly more generalist than adults. When we included the intensity of tick infestation, ticks exhibited a wider diversity of specificity in all life stages. Our results show that ticks of mammals in South Africa tend to behave largely as generalists and that adult ticks are more host-specific. More generally, our analysis shows that the incorporation of life-stage differences, infestation intensity and phylogenetic distances between hosts, as well as the use of more than one specificity index, can all contribute to a deeper understanding of host–parasite interactions.

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Louse (Insecta: Phthiraptera) infestations of the Amur Falcon (Falco amurensis) and the Red-footed Falcon

Ornis Hungarica ◽

10.1515/orhu-2015-0005 ◽

2015 ◽

Vol 23 (1) ◽

pp. 58-65 ◽

Cited By ~ 3

Author(s):

Imre Sándor Piross ◽

Péter Fehérvári ◽

Zoltán Vas ◽

Szabolcs Solt ◽

Éva Horváth ◽

...

Keyword(s):

South Africa ◽

Life History ◽

Host Species ◽

Life History Traits ◽

Population Parameters ◽

Model Species ◽

Host Parasite Interactions ◽

Louse Species ◽

Host Parasite ◽

First Time

Abstract Little is known about the louse species harboured by Red-footed and Amur Falcons despite the fact that various life-history traits of these hosts make them good model species to study host-parasite interactions. We collected lice samples from fully grown Amur (n=20) and Red-footed Falcons (n=59), and from nestlings of Red-footed Falcons (n=179) in four countries: Hungary, India, Italy and South Africa. We identified 3 louse species on both host species, namely Degeeriella rufa, Colpocephalum subzerafae and Laembothrion tinnunculi. The latter species has never been found on these hosts. Comparing population parameters of lice between hosts we found significantly higher prevalence levels of D. rufa and C. subzerafae on Amur Falcons. Adult Red-footed Falcons had higher D. rufa prevalence compared to C. subzerafae. For the first time we also show inter-annual shift in prevalence and intensity levels of these species on Red-footed Falcons; in 2012 on adult hosts C. subzerafae had higher intensity levels than D. rufa, however in 2014 D. rufa had significantly higher intensity compared to C. subzerafae. In case of nestlings both louse species had significantly higher preva lence levels than in 2014. The exact causes of such inter-annual shifts are yet to be understood.

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Correction: Host Specificity And Co-Speciation In Avian Haemosporidia In The Western Cape, South Africa

PLoS ONE ◽

10.1371/journal.pone.0129188 ◽

2015 ◽

Vol 10 (5) ◽

pp. e0129188

Author(s):

Sharon Okanga ◽

Graeme S. Cumming ◽

Philip A. R. Hockey ◽

Lisa Nupen ◽

Jeffrey L. Peters

Keyword(s):

South Africa ◽

Host Specificity ◽

Western Cape

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The drivers of avian haemosporidian prevalence in tropical lowland forest of New Guinea in three dimensions

10.22541/au.162497892.21022475/v1 ◽

2021 ◽

Author(s):

Celia Vinagre-Izquierdo ◽

Kasun Bodawatta ◽

Krystof Chmel ◽

Justinn Renelies-Hamilton ◽

Luda Paul ◽

...

Keyword(s):

Forest Cover ◽

Bird Species ◽

New Guinea ◽

Parasite Prevalence ◽

Host Community ◽

Community Level ◽

Three Dimensions ◽

Effect Of Temperature ◽

Tropical Lowland ◽

Host Parasite

Haemosporidians are among the most common parasites in birds and often impact negatively host fitness and consequently can affect entire host populations. It is therefore important to determine what factors influence parasite prevalence, particularly if they are caused by anthropogenic activities. Here we explore the effect of temperature, forest cover, and proximity to anthropogenic disturbance on haemosporidian prevalence and host-parasite networks on a horizontal spatial scale, comparing four fragmented forest patches and five localities within a continuous forest in Papua New Guinea. We find that the majority of Haemosporidian infections are caused by the genus Haemoproteus and that avian-haemosporidian networks are more specialized in continuous forests. At the community level, only forest cover was negatively associated with Haemoproteus infections, while abiotic and anthropogenic effects on parasite prevalence differed between bird species. We further tested if prevalence and host-parasite networks differed between the canopy and the understorey (vertical stratification) and found significantly higher Haemoproteus prevalence levels in the canopy, and the opposite trend for Plasmodium prevalence. This implies that birds experience distinct parasite pressures depending on the stratum they inhabit, likely driven by differences in vector communities. These three-dimensional analyses of avian-haemosporidians at horizontal and vertical scales provides a deeper understanding of the environmental factors driving haemosporidian prevalence in tropical lowland forests of New Guinea. Collectively, our results suggest that the effect of abiotic variables on haemosporidian infections are species specific, and that factors influencing community-level infections are primarily driven by host community composition.

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