Snake parasitism in an urban old-growth forest

Abstract

Urban-associated changes can have immediate or long-term consequences on animal populations. Such changes may be assessed through parasite prevalence and abundance in wildlife hosts, as urbanization can influence parasitism and disease transmission in wildlife. Snakes are widespread and diverse vertebrates that often persist in urban environments; however, parasitism of snakes in urban environments has yet to be studied, leaving the roles of snakes in parasite transmission uncharacterized. Field ecology, microscopy, molecular techniques, and geographic information science (GIS) were integrated to characterize parasitism of snakes in an urban old-growth forest park. The species, sex, mass, length, location, and prevalence of ecto-, hemo-, and fecal parasites were determined for 34 snakes of 6 species. Ectoparasites (mite), hemoparasites (Hepatozoon spp.), and fecal parasites (Entamoeba spp., Trichomonas spp., Strongloides spp., and an unidentified helminth) were detected in snakes and 64.7 % of snakes were infected by at least one of these parasites. Parasite infections were generally not related to the sex, age, or body condition of snakes. The locations of infected snakes were used to produce risk maps indicating where parasite prevalence is predicted to be greatest. The analysis of these maps indicated that snakes with fecal parasites were closer than non-infected snakes to the edge of the forest. This study confirms that snakes may be important parasite hosts or reservoirs in parasite transmission pathways in urban environments and it provides an integrative multidisciplinary approach that may be used to monitor parasitism dynamics in other urban wildlife areas.

Morphological and molecular identification of ticks infesting Boa constrictor (Squamata, Boidae) in Manaus (Central Brazilian Amazon)

“…In this region there are hundreds of rainforest fragments measuring 1 to 600 ha very close to urban areas. This combination of environments favors the parasitism of snakes by ticks (BENTES, 2013), which may be related to local parasitism dynamics (DAVIS et al, 2012). Despite this fact, only one earlier study has reported specimens of A. dissimile parasitizing a Boa constrictor captured in 1975 in an "INPA secondary forest" (ADIS, 1981).…”

Survey ofHepatozoon(Apicomplexa, Hepatozoidae) Blood Parasites in Small Mammals and Snakes from the Huyck Preserve, New York

“…Both species can also host Hepatozoon eurytopis Telford (Telford 2010). Davis et al (2012) did not report Hepatozoon in these species, although only two individuals of each were sampled, while prevalence was 48% in Agkristrodon contortrix. (L.) (Copperhead Snake; n = 25), all from urban woodland in Tennessee.…”

Dehydration enhances cellular and humoral immunity in a mesic snake community

“…Concurrently, we also checked for ectoparasites (ticks or mites), which were rarely observed (<7% of snakes). Thus, hemoparasites were used as a proxy for parasite burden because hemoparasites are common in snakes (Davis et al, 2012; Telford, 2009), can influence fitness‐related traits in snakes (Madsen, Ujvari, & Olsson, 2005; but see Brown, Shilton, & Shine, 2006), and can be determined in a minimally invasive fashion (i.e., via blood smears: see Section 2.3 below). We subcutaneously implanted each snake with a passive integrated transponder (12 mm) for future identification and returned each snake to its site of capture within 18 hr.…”