Health Assessment of Free-Ranging Chelonians in an Urban Section of the Bronx River, New York, Usa

Abstract

The Bronx River in Bronx, New York spans an area of significant human development and has been subject to historic and ongoing industrial contamination. We evaluated the health of free-ranging native common snapping turtles ( Chelydra serpentina) and nonnative invasive red-eared sliders ( Trachemys scripta) in a segment of the Bronx River between May and July 2012. In 18 snapping turtles and nine sliders, complete physical examinations were performed, ectoparasites collected, and blood was analyzed for contaminants (mercury, thallium, cadmium, arsenic, lead, selenium, oxychlordane, alpha-chlordane, dieldrin, dichlorodiphenyldichloroethane [DDD], dichlorodiphenyldichloroethylene [DDE], polychlorinated biphenyls). Complete blood counts and the presence of hemoparasites were determined in 16 snapping turtles and nine sliders. Swabs of the choana and cloaca were screened for ranavirus, adenovirus, herpesvirus, and Mycoplasma spp. by PCR in 39 snapping turtles and 28 sliders. Both turtle species exhibited bioaccumulation of various environmental contaminants, particularly organochlorines and polychlorinated biphenyls. Molecular screening revealed a unique herpesvirus in each species. A Mycoplasma sp. previously isolated from emydid turtles was detected in red-eared sliders while a unique Mycoplasma sp. was identified in common snapping turtles. Ranaviruses and adenoviruses were not detected. Our study established a baseline health assessment to which future data can be compared. Moreover, it served to expand the knowledge and patterns of health markers, environmental contaminants, and microorganisms of free-ranging chelonians.

Herpesviruses in Captive Chelonians in Europe Between 2016 and 2020

“…Glyptemys herpesvirus 1 and glyptemys herpesvirus 2 were both detected in asymptomatic bog and wood turtles (Glyptemys insculpta) (26). Trachemys herpesvirus 1 has been detected in asymptomatic free ranging red-eared sliders (Trachemys scripta elegans) in the United States (27). Emydoidea herpesvirus 1 was detected in free ranging Blanding's turtles (Emydoidea blandingii) in the United States (28), while Emydoidea herpesvirus 2 was detected in a squamous cell carcinoma in the oral cavity of a free ranging Blanding's turtle (29).…”

Plasma complement activation mechanisms differ in ornate (Terrapene ornata ornata) and eastern box turtles (Terrapene carolina carolina)

“…(Adamovicz, unpublished data) and herpesviral antibody presence (Chaffin et al, 2008) have also been identified in wild turtles. While ranavirus (Carstairs et al, 2020;McKenzie et al, 2019), herpesvirus (Aplasca et al, 2019), and Mycoplasma sp. (Aplasca et al, 2019), have been detected in common snapping turtles, clinical disease appears uncommon in this species (Aplasca et al, 2019;Carstairs et al, 2020).…”

“…While ranavirus (Carstairs et al, 2020;McKenzie et al, 2019), herpesvirus (Aplasca et al, 2019), and Mycoplasma sp. (Aplasca et al, 2019), have been detected in common snapping turtles, clinical disease appears uncommon in this species (Aplasca et al, 2019;Carstairs et al, 2020). Eastern box turtles and alligator snapping turtles utilize the lectin pathway of complement activation, while ornate box turtles and common snapping turtles use the alternative pathway; potentially indicating that the alternative pathway stimulates more comprehensive protection against invading pathogens (Baker, Kessler, Darville-Bowleg, et al, 2019).…”

Herpesviruses in Reptiles

“…Recent epidemiological studies have largely relied on molecular methods to identify potential genetic and environmental risk factors associated with reptilian HVs ( 24 , 80 , 138 , 167 – 169 ). Species-specific PCR-based assays targeting specific gene segments of reptilian HVs have been developed and validated ( 78 , 170 ).…”

“…Generally, HVs replicate within host cell nuclei and are able to remain latent in their natural hosts ( 17 , 23 ). So far, reptilian HVs that have been identified and characterised all belong to the subfamily Alphaherpesvirinae ( 17 , 24 – 26 ).…”