Spatial ecology of invasive Burmese pythons in southwestern Florida

Abstract

Understanding the spatial ecology of an invasive species is critical for designing effective control programs. Determining and quantifying home range estimates and habitat associations can streamline targeted removal efforts for wide-ranging, cryptic animals. The Burmese python (Python bivittatus) is a large-bodied constrictor snake with an established and expanding invasive population in southern Florida. This apex predator has severely impacted native wildlife across the Greater Everglades ecosystem. However, limited ecological information exists on this invasive species at the landscape level. Here, we present results from a study using radiotelemetry to quantify movements and habitat use patterns of 25 adult Burmese pythons in southwestern Florida, USA, for average periods of 814 d (range: 288-1809). Our objective was to quantify home range size, movement rates, and second-and third-order habitat selection. Mean annual home range size was 7.5 km 2 AE 2.9 km 2 (95% kernel density estimate), and pythons moved at a maximum mean daily rate of 0.52 km/d. Burmese pythons selected agriculture, freshwater wetland, saline wetland, and upland land cover classes but avoided open water and urban land cover classes. Nest site selection was highest for pythons at an elevation of 1.7 m with nesting hotspots concentrated on the borders of urban and agricultural areas or in sandy forested upland habitats. A broader understanding of the spatial utilization of Burmese pythons will enhance the utility of emerging control strategies across their invaded range.

Clutch may predict growth of hatchling Burmese pythons better than food availability or sex

“…There were 71 fertile eggs (19.4 kg) in C1 that all hatched, and there were 61 fertile eggs (12.5 kg) in C2, 50 of which hatched. The females that laid the clutches were part of a long-term radio-telemetry study examining adult Burmese python spatial ecology ( Bartoszek et al, 2021 ). After laying eggs, the C1 female weighed 54.5 kg and was approximately 4.9 m total length, and the C2 female weighed 29.5 kg and was approximately 4.3 m total length.…”

“…In 2015, we had the rare opportunity to obtain several large clutches of eggs laid in the wild by free-ranging Burmese pythons that were a byproduct of a long-term radio-telemetry study examining their spatial ecology in southwestern Florida, USA ( Bartoszek et al, 2021 ). We used the hatchlings from these clutches to conduct an experiment in captivity to determine if food availability, clutch, and sex might influence their growth patterns.…”

Burmese pythons in Florida: A synthesis of biology, impacts, and management tools

“…During this time, adult python gonadal resurgence is observed in both sexes and is generally correlated with body size and weight, peaking in females with developing follicles (Currylow et al 2022b). Breeding aggregations of up to eight individual pythons have been documented in lowland forests (tree islands) that are slightly elevated above the surrounding wetland habitat in ENP (Smith et al 2016), and mating season activity has been associated with elevated habitats such as xeric scrub and oak hammocks in southwestern Florida (Bartoszek et al 2021b). Courtship of female Burmese pythons by males may be facilitated by the presence of external sexually dimorphic cloacal spurs which are remnants of the pelvic girdle and capable of movement.…”

Spatial ecology to strengthen invasive snake management on islands

“…Information on the biology and ecology of invasive predators can be crucial (Courchamp et al, 2003;IUCN, 2018), but particularly home range, activity patterns, or habitat use (Bartoszek et al, 2021;Rouco et al, 2017) can contribute to design more effective trapping strategies (Bengsen et al, 2016;Genovesi, 2000). This information becomes even more relevant in species di cult to manage like snakes (Avery et al, 2014;Boback et al, 2020), which show extremely low detectability, secretive behavior, cryptic coloration, sporadic activity patterns, or use inaccessible habitats (Parker & Plummer, 1987;Turner, 1977).…”

“…This information becomes even more relevant in species di cult to manage like snakes (Avery et al, 2014;Boback et al, 2020), which show extremely low detectability, secretive behavior, cryptic coloration, sporadic activity patterns, or use inaccessible habitats (Parker & Plummer, 1987;Turner, 1977). As invasive snakes are being increasingly recognized as a major threat to biodiversity in numerous islands worldwide (Kraus, 2015;Wiles et al, 2003), gaining knowledge on their spatial ecology is key to optimize control actions (Bartoszek et al, 2021;Mullin & Seigel, 2009;Tobin et al, 1999). However, this information remains unknown or poorly studied in most of the world's invasive snakes.…”