Interactions between the invasive Burmese python, Python bivittatus Kuhl, and the local mosquito community in Florida, USA

Abstract

The Burmese python, Python bivittatus Kuhl, is a well-established invasive species in the greater Everglades ecosystem of southern Florida, USA. Most research on its ecological impacts focuses on its role as a predator and its trophic interactions with native vertebrate species, particularly mammals. Beyond predation, there is little known about the ecological interactions between P. bivittatus and native faunal communities. It is likely that established populations of P. bivittatus in southern Florida serve as hosts for native mosquito communities. To test this concept, we used mitochondrial cytochrome c oxidase subunit I DNA barcoding to determine the hosts of blood fed mosquitoes collected at a research facility in northern Florida where captive P. bivittatus and Argentine black and white tegu, Salvator merianae (Duméril and Bibron), are maintained in outdoor enclosures, accessible to local mosquitoes. We recovered python DNA from the blood meals of three species of Culex mosquitoes: Culex erraticus (Dyar and Knab), Culex quinquefasciatus Say, and Culex pilosus (Dyar and Knab). Culex erraticus conclusively (P = 0.001; Fisher’s Exact Test) took more blood meals from P. bivittatus than from any other available host. While the majority of mosquito blood meals in our sample were derived from P. bivittatus, only one was derived from S. merianae. These results demonstrate that local mosquitoes will feed on invasive P. bivittatus, a recently introduced host. If these interactions also occur in southern Florida, P. bivittatus may be involved in the transmission networks of mosquito-vectored pathogens. Our results also illustrate the potential of detecting the presence of P. bivittatus in the field through screening mosquito blood meals for their DNA.

Barcoding blood meals: New vertebrate-specific primer sets for assigning taxonomic identities to host DNA from mosquito blood meals

“…Two primers, a vertebrate universal forward primer (Mod_RepCOI_F) and a universal reverse primer (Mod_RepCOI_R), were designed from an existing primer pair (RepCOI_F and RepCOI_R) that was originally created for DNA barcoding Madagascan reptiles [ 24 ] and has been used without modification in blood meal analysis targeting reptilian hosts [ 8 ]. The forward primer sequence and its position were modified to accommodate mosquito-vertebrate nucleotide mismatches toward the 3' end.…”

“…For the barcoding region of the vertebrate cytochrome c oxidase subunit I gene ( COI ), few primers are available that fit the needs of blood meal analysis applications. Those that are available are either specific to certain host classes [ 6 , 7 , 8 ], limiting the ability to detect the full range of hosts, or involve nested amplification reactions [ 9 , 10 ] that require greater resource and effort investment. Similarly, primer sets, mostly vertebrate class-specific, are available for another DNA barcoding marker, cyt b [ 11 – 13 ].…”

Host Associations of Culex (Melanoconion) atratus (Diptera: Culicidae) and Culex (Melanoconion) pilosus from Florida, USA

“…Mosquitoes were removed from the resting shelters each morning of the sampling event between 0900 and 1100 h while using a battery-powered aspirator constructed from a Dustbuster™ (Black & Decker ® , Towson, MD, USA) handheld vacuum modified to hold plastic collection canisters with wire mesh bottoms (BioQuip Products, Rancho Dominguez, CA, USA), as described in Bingham et al [26]. Various methods were used to minimize the escape of resting mosquitoes during collection including using baffles [23,24]. The same aspirators were used to collect mosquitoes from natural resting sites (e.g., root masses of fallen trees, bases of tree trunk, tree cavities, dense vegetation).…”

“…From these, birds (26.0%), humans (20.5%), horses (32.9%), and dogs (20.5%) were identified as hosts. In a recent study, Reeves et al [23] used DNA barcoding to identify five Cx. pilosus blood meals from northern Florida and found four were derived from reptilian hosts and one from an avian host.…”

Interactions between the imperiled West Indian manatee, Trichechus manatus, and mosquitoes (Diptera: Culicidae) in Everglades National Park, Florida, USA

“…Some mosquito species are host specialists of frogs, including ranids that are closely associated with aquatic habitats 4 – 6 , and fishes, e.g., mudskippers, other gobies, and eels 7 , 8 . Crocodilians 9 , 10 , and semi-aquatic snakes and turtles (e.g., Agkistrodon piscivorus , Python bivittatus , and Trachemys scripta ) often serve as hosts for opportunistic mosquitoes 11 – 13 . There is no direct evidence of interactions between mosquitoes and marine mammals in nature, however, mosquito-vectored viruses (e.g., West Nile virus, Eastern equine encephalitis virus, St. Louis encephalitis virus, and Venezuelan equine encephalitis virus) or immunologic evidence of virus infection have been detected in captive orcas 14 , 15 and wild Atlantic bottlenose dolphins 16 .…”