Ectoparasite diversity and infection burden on two sympatric bat species, Myotis lucifugus and M. septentrionalis (Chiroptera: Vespertilionidae)

Parasites are an abundant and diverse group of organisms that are often
excluded from biodiversity surveys, limiting our understanding of
host-parasite relationships and parasite diversity. Parasites are
dependent on their hosts for survival and parasite populations are at risk
if their host populations decline. The aim of our study was to quantify
and compare the ectoparasite communities of two sympatric Atlantic
Canadian bat species, Myotis lucifugus and M. septentrionalis.
Ectoparasites were collected from bats captured for research throughout
Atlantic Canada between 1999 and 2017 during the active season (May to
October). Ectoparasites were identified based on morphological
characteristics. The prevalence and mean intensity of infection was
calculated for each ectoparasite species per collection region and based
on host age class and sex. Generalized linear mixed models were used to
assess host differences in infection by the two most abundant
ectoparasites. Both bat species hosted ectoparasite communities dominated
by the mite Spinturnix americanus and the flea Myodopsylla insignis with
other ectoparasites being rarely encountered. Despite being the most
common ectoparasites of both bat species, our results suggest that
infections of these ectoparasites vary between them with M. insignis
prevalence being greater on M. lucifugus and S. americanus prevalence
being greater on M. septentrionalis. We suggest these differences in
infection burden are related to the social and roosting behaviours of
these hosts and the life history of the ectoparasites. Monitoring
parasites concurrently with focal species is important for capturing this
aspect of biodiversity and for understanding how host-parasite dynamics
may be disrupted if hosts undergo drastic demographic changes.