Using Scout Burmese Pythons and Detector Dogs to Protect Endangered Species in the Florida Keys

Science Center Objects

WARC researchers are addressing an urgent need to identify specific habitat use of pythons on Key Largo, FL.

The Science Issue and Relevance: Over 60 pythons have been captured in Key Largo since 2007. Necropsies of these show evidence of Key Largo wood rat (KLWR) depredation, and it is possible they also prey upon other listed species such as the Key Largo cotton mouse (KLCM) and American crocodile. The threat that pythons pose to native wildlife in the upper Keys, combined with pressures from  other non-native species (e.g., feral cats) could be disastrous for the KLWR.

Invasive Burmese Python

Invasive Burmese python in the Greater Everglades (credit: Brian Smith, USGS)

Pythons can completely alter the food web within ecosystems. Pythons are cryptic and in the absence of substantial data documenting habitat use on Key Largo, it’s difficult to differentiate what habitats are being utilized (and to what degree). Scout python work (i.e., using pythons to locate other pythons; see Smith et al. 2016) can help shed light on the presence (or absence) of breeding females within the study site, and the selection of breeding sites. Given the relatively small size of the conservation lands on North Key Largo, Scout python work could allow us to identify high-density python locations and inform future removal efforts to slow both population growth and spread of pythons across the Florida Keys.

This project will address an urgent need to identify specific habitat use of pythons on Key Largo (including Crocodile Lake National Wildlife Refuge, Dagny Johnson Botanical State Park, and John Pennekamp Coral Reef State Park). This information is needed to focus removal efforts for pythons and prevent the extinction of the KLWR and KLCM. Python numbers in Key Largo are not thought to be as high as in other parts of South Florida, so there is an opportunity to get ahead of this problem before long lasting ecological damage is caused. Because of its location within the Florida Keys, reduction of the python threat in Key Largo would benefit wildlife in areas further south in the Middle and Lower Keys where pythons have not been established.  Several federally endangered species such as the key deer, Lower Keys marsh rabbit, and silver rice rat, as well as many at-risk species that would all be extremely vulnerable to python predation inhabit these Keys. This project has the potential to place “a line in the sand” to help reduce population spread and protect biological resources in the lower keys. The Recovery Plans for KLWR, KLCM, American crocodile, key deer, Lower Keys marsh rabbit, and silver rice rat all have species-level recovery actions that seek to reduce or eliminate mortality from non-native predators, such as pythons.

North Key Largo study site

Study area on North Key Largo, including grid of hexagonal cells used to monitor endangered Key Largo woodrat (Public domain.)

Methodology for Addressing the Issue:  Pythons will be captured during routine searches or opportunistically in Key Largo. Captured pythons (>7 ft.) of breeding size will have a very-high-frequency (VHF) radio tag and an accelerometer internally implanted. Each instrumented python would be located via VHF telemetry two or more times per week. Individual pythons will be followed closely during mating season (November through March) to find mating groups and remove other pythons from the population. A python detector dog “Percy” was purchased with a grant from the Ocean Reef Community Association. Percy has been successful finding wild pythons in the Everglades and will be used to survey areas for the presence of pythons, including core occupied habitat for the KLWR/KLCM, areas adjacent to scout pythons, nesting areas for American crocodiles and areas with recent python sightings. Given the relatively small size of the conservation lands on Key Largo, detection dogs and scout python work could allow us to identify high-density python areas and inform future removal efforts to slow both population growth and spread of pythons across the Florida Keys.  These efforts are important for the control of invasive constrictor species, island conservation, and endangered species recovery worldwide.

Future Steps: Future efforts could include the continued use of Scout pythons, telemetry, and detection dogs to track pythons and their impacts on native wildlife and habitat use. GPS technology will continue to play an increasing role, allowing us to refine our understanding of python spatial distribution throughout the Florida Keys. These efforts will provide a better understanding of the biology and ecological impact of invasive pythons and provide insight into ways to exploit their biology to control their population.