霊長類絶滅危惧種における寄生虫群集構造の改変

抄録

Understanding the interplay between hosts and parasites is critical because infectious diseases can contribute to declines of endangered species. Parasites are a major part of ecological communities, but because they rely on small, discrete habitats (i.e. their hosts), they are also increasingly threatened by habitat loss and fragmentation. A comparative study using the Global Mammal Parasite Database (GMPD) – a web repository of studies reporting primate-parasite associations – reported in 2007 that threatened primates have less-rich parasite communities. We replicated that study using the recently-released version 2 of the GMPD, published in 2017. Specifically, we predicted a lower diversity and narrower distribution of parasites in threatened hosts, i.e. hosts that represent shrinking and fragmented parasite habitat, particularly in parasites with limited host range (i.e. host specialists). Focusing on helminth and protozoan parasite records in the GMPD and using phylogenetic comparative analyses in a Bayesian mixed-modeling framework, we found weak evidence that parasite richness was lower in threatened primates, but stronger evidence that generalist parasites have disproportionately higher prevalence than specialists in these hosts. Since generalist parasites are also more likely than specialists to negatively impact their hosts, this may represent an additional challenge for endangered species to cope with. We conclude that host endangerment may alter parasite community structure in ways that can put primates at further risk of disease.