Multi-year Burmese Python Vital Rate Research Collaborative in the Greater Everglades
USGS researchers will track juvenile Burmese python within Big Cypress National Preserve (BICY) and collect data on snake growth, habitat use, and causes of mortality. Known-fate models will be used to estimate survival and better understand factors that influence survival.
The Science Issue and Relevance: Although much research has been conducted on pythons in southern Florida, estimates of vital rates (e.g., age-specific survival rates, age at maturity, and variation in reproductive output and frequency) are not well described. This information is needed to construct a life table, which can inform python management efforts and the degree of confidence surrounding management scenarios. Vital rates are critical to accurately identifying the best age class to target for specific management objectives, estimating population growth or declines, and understanding the number of individuals that must be removed to ensure population decline. However, obtaining vital rates requires long-term tracking and field data collection.
This project seeks to obtain demographic information on pythons to maximize efficacy of various control efforts. Additionally, the project can explore questions about python movement, habitat use, causes of mortality, and the most effective removal efforts (both temporally and geographically) to cause population declines. Further, python vital rates and improved understanding of python breeding biology (e.g., prevalence of multiple paternity, average number of clutches per year per female, sub-adult dispersal, reproductive cycles of females) will provide the foundational metrics for future genetic biocontrol research on this species.
The project responds to research needs outlined in the DOI Science Plan to develop effective control methods for exotic aquatic vertebrates, for research into the life history of non-native species, and to determine impacts of exotic species on native species on federally managed lands.
Methodology for Addressing the Issue: We will track both opportunistically collected juveniles and juveniles produced by free-ranging radio-telemetered adult females that nest at two sites within Big Cypress National Preserve (BICY). After hatching, snakes will be implanted with radio tags and released at their nest location or point of origin within BICY. The status (live or dead) of each radio-tagged study animal will be determined on a regular basis. We will collect data on snake growth, habitat use, and causes of mortality, and use known-fate models to estimate survival and better understand factors that influence survival.
Future Steps: Results from this research will contribute to a more complete understanding of python biology and ecology and can help inform the development of future genetic biocontrol tools and other innovative management approaches. Genetic biocontrol approaches are relatively novel outside of invertebrate and rodent models. As such, life history data is essential to understand which genetic biocontrol strategy is best suited to an organism, but also to allow for efficient deployment of methods in the target population.
Python Vital Rates
USGS Coordinated Burmese Python Research Strategy for South Florida (FY21 – FY27)
Using Scout Burmese Pythons and Detector Dogs to Protect Endangered Species in the Florida Keys
Applications of Advanced Tracking and Modeling Tools with Burmese Pythons across South Florida's Landscape
Habitat Selection of the Burmese Python in the Florida Everglades
Ecology of and Control Strategies for Invasive Burmese Pythons (Python molurus bivitattus) in the Greater Everglades
USGS researchers will track juvenile Burmese python within Big Cypress National Preserve (BICY) and collect data on snake growth, habitat use, and causes of mortality. Known-fate models will be used to estimate survival and better understand factors that influence survival.
The Science Issue and Relevance: Although much research has been conducted on pythons in southern Florida, estimates of vital rates (e.g., age-specific survival rates, age at maturity, and variation in reproductive output and frequency) are not well described. This information is needed to construct a life table, which can inform python management efforts and the degree of confidence surrounding management scenarios. Vital rates are critical to accurately identifying the best age class to target for specific management objectives, estimating population growth or declines, and understanding the number of individuals that must be removed to ensure population decline. However, obtaining vital rates requires long-term tracking and field data collection.
This project seeks to obtain demographic information on pythons to maximize efficacy of various control efforts. Additionally, the project can explore questions about python movement, habitat use, causes of mortality, and the most effective removal efforts (both temporally and geographically) to cause population declines. Further, python vital rates and improved understanding of python breeding biology (e.g., prevalence of multiple paternity, average number of clutches per year per female, sub-adult dispersal, reproductive cycles of females) will provide the foundational metrics for future genetic biocontrol research on this species.
The project responds to research needs outlined in the DOI Science Plan to develop effective control methods for exotic aquatic vertebrates, for research into the life history of non-native species, and to determine impacts of exotic species on native species on federally managed lands.
Methodology for Addressing the Issue: We will track both opportunistically collected juveniles and juveniles produced by free-ranging radio-telemetered adult females that nest at two sites within Big Cypress National Preserve (BICY). After hatching, snakes will be implanted with radio tags and released at their nest location or point of origin within BICY. The status (live or dead) of each radio-tagged study animal will be determined on a regular basis. We will collect data on snake growth, habitat use, and causes of mortality, and use known-fate models to estimate survival and better understand factors that influence survival.
Future Steps: Results from this research will contribute to a more complete understanding of python biology and ecology and can help inform the development of future genetic biocontrol tools and other innovative management approaches. Genetic biocontrol approaches are relatively novel outside of invertebrate and rodent models. As such, life history data is essential to understand which genetic biocontrol strategy is best suited to an organism, but also to allow for efficient deployment of methods in the target population.