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Jillian M Josimovich, M.Sc. (Former Employee)

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USGS Biological Science Technician Michelle Collier holds an invasive Argentine Tegu lizard.

Mentoring the next generation: USGS, NPS, and University of Florida Cooperative Research Unit Invasive Reptile Intern Program

Invasive reptiles like the Burmese python ( Python bivittatus ) and black and white tegu lizard ( Tupinambis merianae ) are exerting tremendous harm on Everglades ecosystems, but these problematic species present an excellent opportunity to engage the next generation in science. Since entering into an agreement with Everglades National Park in late 2013, the Invasive Species Science Branch of the...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
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Mentoring the next generation: USGS, NPS, and University of Florida Cooperative Research Unit Invasive Reptile Intern Program

Invasive reptiles like the Burmese python ( Python bivittatus ) and black and white tegu lizard ( Tupinambis merianae ) are exerting tremendous harm on Everglades ecosystems, but these problematic species present an excellent opportunity to engage the next generation in science. Since entering into an agreement with Everglades National Park in late 2013, the Invasive Species Science Branch of the...
Learn More
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Everglades National Park

USGS Everglades Research Office - Florida

The Daniel Beard Center in Everglades National Park provides the base for most of the field work done on the control of invasive reptiles by USGS Fort Collins Science Center staff. The team works in Everglades National Park, Big Cypress National Preserve, Crocodile Lake National Wildlife Refuge, and other parts of the Greater Everglades Ecosystem focusing on, among other species of concern...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Land Management Research Program, Fort Collins Science Center
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USGS Everglades Research Office - Florida

The Daniel Beard Center in Everglades National Park provides the base for most of the field work done on the control of invasive reptiles by USGS Fort Collins Science Center staff. The team works in Everglades National Park, Big Cypress National Preserve, Crocodile Lake National Wildlife Refuge, and other parts of the Greater Everglades Ecosystem focusing on, among other species of concern...
Learn More
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USGS intern Jillian Josimovich displays a recently captured Burmese python, an invasive species in Everglades National Park.

Cruising to Improve the Detection of Burmese Pythons in Everglades National Park

It is not uncommon to see researchers cruising around Everglades National Park (ENP) on what has been a routine basis for the past ten months. Every evening, interns pack into a Chevy Volt for their shift assisting the U.S. Geological Survey in conducting Burmese Python (Python molurus bivittatus) nighttime surveillance through observational surveys. This effort to detect non-native snakes, namely...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
link

Cruising to Improve the Detection of Burmese Pythons in Everglades National Park

It is not uncommon to see researchers cruising around Everglades National Park (ENP) on what has been a routine basis for the past ten months. Every evening, interns pack into a Chevy Volt for their shift assisting the U.S. Geological Survey in conducting Burmese Python (Python molurus bivittatus) nighttime surveillance through observational surveys. This effort to detect non-native snakes, namely...
Learn More

Diet of invasive Burmese Pythons (Python molorus bivittatus) in southern Florida, 1995-2020

Digestive tract contents were identified to provide an account of Burmese python diet. Diet contents came from 1716 pythons collected by cooperators during 1995-2020 from public and private lands across southern Florida, primarily within the Greater Everglades Ecosystem. Burmese pythons consumed 76 species of fauna across three taxonomic classes (Aves, Mammalia, and Reptilia). 
By
Fort Collins Science Center

Size distribution and reproductive data of the invasive Burmese python (Python molurus bivittatus) in the Greater Everglades Ecosystem, Florida, USA, 1995-2021

This dataset contains morphometric information from Burmese pythons collected from an invasive population in southern Florida between 1995-2021. Scientists from the U.S. Geological Survey and the National Park Service curated this dataset as a repository for records of Burmese pythons found on or nearby federal lands in southern Florida, including Everglades National Park, Big Cypress National Pre
By
Fort Collins Science Center

Hatchling Growth Experiment Dataset from Invasive Burmese Pythons Captured in 2015 in Southern Florida

This dataset contains information about 58 hatchling Burmese pythons collected in 2015 from an invasive population in southern Florida. These hatchlings were used in an experiment that assessed the effects of food availability, clutch, and sex on their growth in captivity. The hatchlings were collected as eggs from the nests of two wild pythons, assigned to High or Low feeding treatments, and thei
By
Fort Collins Science Center
Burmese python hatchling
Burmese python hatchling
Burmese python hatchling
Burmese python hatchling

Burmese python hatchling

Burmese python hatchling

Non-native Burmese pythons have established a breeding population in South Florida and are one of the most concerning invasive species in Everglades National Park. This photograph is of a Burmese python hatchling

By
Ecosystems, Fort Collins Science Center, Communications and Publishing
Burmese python hatchling

Burmese python hatchling

Burmese python hatchling

Non-native Burmese pythons have established a breeding population in South Florida and are one of the most concerning invasive species in Everglades National Park. This photograph is of a Burmese python hatchling

By
Ecosystems, Fort Collins Science Center, Communications and Publishing

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

Burmese pythons (Python molurus bivittatus) are native to southeastern Asia, however, there is an established invasive population inhabiting much of southern Florida throughout the Greater Everglades Ecosystem. Pythons have severely impacted native species and ecosystems in Florida and represent one of the most intractable invasive-species management issues across the globe. The difficulty stems f
Authors
Jacquelyn C. Guzy, Bryan G. Falk, Brian J. Smith, John David Willson, Robert Reed, Nicholas Aumen, Michael L. Avery, Ian A. Bartoszek, Earl Campbell, Michael Cherkiss, Natalie M. Claunch, Andrea Faye Currylow, Tylan Dean, Jeremy Dixon, Richard M. Engeman, Sarah Funck, Rebekah Gibble, Kodiak C. Hengstebeck, John S. Humphrey, Margaret Hunter, Jillian Josimovich, Jennifer Ketterlin Eckles, Michael Kirkland, Frank J. Mazzotti, Robert A. McCleery, Melissa A. Miller, Matthew F. McCollister, M. Rockwell Parker, Shannon E. Pittman, Michael R. Rochford, Christina Romagosa, Art Roybal, Ray W. Snow, McKayla M. Spencer, Hardin Waddle, Amy A. Yackel Adams, Kristen Hart
By
Ecosystems Mission Area, Fort Collins Science Center, Pacific Island Ecosystems Research Center, Wetland and Aquatic Research Center

Egg retention in wild-caught Python bivittatus in the Greater Everglades Ecosystem, Florida, USA

Retention of eggs in oviducts beyond the normal oviposition period is a common problem for captive reptiles, but the occurrence of egg retention in wild populations is largely unknown. The Burmese python (Python [molurus] bivittatus; Kühl 1820) is an oviparous snake native to south-eastern Asia that is now established in southern Florida. From 2011–2019, invasive Burmese pythons were opportunistic
Authors
Gretchen Erika Anderson, Frank N. Ridgley, Jillian Maureen Josimovich, Robert Reed, Bryan G. Falk, Amy A. Yackel Adams, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Face-off: Novel depredation and nest defense behaviors between an invasive and a native predator in the Greater Everglades Ecosystem, Florida, USA

We describe several photo-documented novel interactions between intraguild predators in southern Florida—the native bobcat (Lynx rufus) and the invasive Burmese python (Python bivittatus). Over several days we documented a bobcat's depredation of an unguarded python nest and subsequent python nest defense behavior following the return of both animals to the nest. This is the first documentation of
Authors
Andrea Faye Currylow, Matthew F. McCollister, Gretchen Erika Anderson, Jillian Maureen Josimovich, Austin Lee Fitzgerald, Christina M. Romagosa, Amy A. Yackel Adams
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Agkistrodon conanti (Florida Cottonmouth) and Python bivittatus (Burmese Python). Diet and Predation

Python bivittatus is established in the Greater Everglades Ecosystem in southern Florida, USA. Documented predators on pythons in Florida include Alligator mississippiensis (American Alligator; Snow et al. 2006. Herpetol. Rev. 37:81–81), Drymarchon couperi (Gulf Coast Indigo Snake; Andreadis et al. 2018. Herpetol. Rev. 49:341–342), Lynx rufus (Bobcat; McCollister et al. 2021. Southeast. Nat. 20:N5
Authors
Ian A. Bartoszek, Gretchen Erika Anderson, Ian Easterling, Jillian Maureen Josimovich, Alex Furst, Frank N. Ridgley, Austin Lee Fitzgerald, Amy A. Yackel Adams, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

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

Identifying which environmental and genetic factors affect growth pattern phenotypes can help biologists predict how organisms distribute finite energy resources in response to varying environmental conditions and physiological states. This information may be useful for monitoring and managing populations of cryptic, endangered, and invasive species. Consequently, we assessed the effects of food a
Authors
Jillian Maureen Josimovich, Bryan G. Falk, Alejandro Grajal-Puche, Emma B. Hanslowe, Ian A. Bartoszek, Robert Reed, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Identifying negative sentiment polarity in the Judas technique

In the context of conservation science and management, the Judas technique refers to outfitting an animal (a Judas animal) with a radio transmitter or other identifier so that its movements can be tracked to locate conspecifics. Although this term is commonly used, some consider it offensive due to historical associations of the word Judas with anti-Semitic sentiments. Thus, the term has a negativ
Authors
Austin Lee Fitzgerald, Jillian Maureen Josimovich, Charlotte J. Robinson, Robert Reed, Andrea Faye Currylow
By
Ecosystems Mission Area, Fort Collins Science Center

Native mammalian predators can depredate adult Burmese Pythons in Florida

Invasive predators are of conservation concern because they contribute to species declines and extinctions worldwide. Interactions of native fauna and invasive predators can be complex, but understanding these relationships can guide management and restoration. Observations of these interactions are especially important for invaders with low detectability like Python bivittatus (Burmese Python) wh
Authors
Matthew F. McCollister, Jillian Maureen Josimovich, Austin Lee Fitzgerald, Deborah K. Jansen, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Using enclosed Y-mazes to assess chemosensory behavior in reptiles

Reptiles utilize a variety of environmental cues to inform and drive animal behavior such as chemical scent trails produced by food or conspecifics. Decrypting the scent-trailing behavior of vertebrates, particularly invasive species, enables the discovery of cues that induce exploratory behavior and can aid in the development of valuable basic and applied biological tools. However, pinpointing be
Authors
M. Rockwell Parker, Andrea Faye Currylow, Eric A. Tillman, Charlotte J. Robinson, Jillian Maureen Josimovich, Isabella M.G. Bukovich, Lauren A. Nazarian, Melia G. Nafus, Bryan M. Kluever, Amy A. Yackel Adams
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
Next Generation of Women in Science

Next Generation of Women in Science

As part of International Day of Women and Girls in Science, Fort Collins Science Center scientists volunteered to pass along personal and professional...

Read Article

Science and Products

link
USGS Biological Science Technician Michelle Collier holds an invasive Argentine Tegu lizard.

Mentoring the next generation: USGS, NPS, and University of Florida Cooperative Research Unit Invasive Reptile Intern Program

Invasive reptiles like the Burmese python ( Python bivittatus ) and black and white tegu lizard ( Tupinambis merianae ) are exerting tremendous harm on Everglades ecosystems, but these problematic species present an excellent opportunity to engage the next generation in science. Since entering into an agreement with Everglades National Park in late 2013, the Invasive Species Science Branch of the...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
link

Mentoring the next generation: USGS, NPS, and University of Florida Cooperative Research Unit Invasive Reptile Intern Program

Invasive reptiles like the Burmese python ( Python bivittatus ) and black and white tegu lizard ( Tupinambis merianae ) are exerting tremendous harm on Everglades ecosystems, but these problematic species present an excellent opportunity to engage the next generation in science. Since entering into an agreement with Everglades National Park in late 2013, the Invasive Species Science Branch of the...
Learn More
link
Everglades National Park

USGS Everglades Research Office - Florida

The Daniel Beard Center in Everglades National Park provides the base for most of the field work done on the control of invasive reptiles by USGS Fort Collins Science Center staff. The team works in Everglades National Park, Big Cypress National Preserve, Crocodile Lake National Wildlife Refuge, and other parts of the Greater Everglades Ecosystem focusing on, among other species of concern...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Land Management Research Program, Fort Collins Science Center
link

USGS Everglades Research Office - Florida

The Daniel Beard Center in Everglades National Park provides the base for most of the field work done on the control of invasive reptiles by USGS Fort Collins Science Center staff. The team works in Everglades National Park, Big Cypress National Preserve, Crocodile Lake National Wildlife Refuge, and other parts of the Greater Everglades Ecosystem focusing on, among other species of concern...
Learn More
link
USGS intern Jillian Josimovich displays a recently captured Burmese python, an invasive species in Everglades National Park.

Cruising to Improve the Detection of Burmese Pythons in Everglades National Park

It is not uncommon to see researchers cruising around Everglades National Park (ENP) on what has been a routine basis for the past ten months. Every evening, interns pack into a Chevy Volt for their shift assisting the U.S. Geological Survey in conducting Burmese Python (Python molurus bivittatus) nighttime surveillance through observational surveys. This effort to detect non-native snakes, namely...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
link

Cruising to Improve the Detection of Burmese Pythons in Everglades National Park

It is not uncommon to see researchers cruising around Everglades National Park (ENP) on what has been a routine basis for the past ten months. Every evening, interns pack into a Chevy Volt for their shift assisting the U.S. Geological Survey in conducting Burmese Python (Python molurus bivittatus) nighttime surveillance through observational surveys. This effort to detect non-native snakes, namely...
Learn More

Diet of invasive Burmese Pythons (Python molorus bivittatus) in southern Florida, 1995-2020

Digestive tract contents were identified to provide an account of Burmese python diet. Diet contents came from 1716 pythons collected by cooperators during 1995-2020 from public and private lands across southern Florida, primarily within the Greater Everglades Ecosystem. Burmese pythons consumed 76 species of fauna across three taxonomic classes (Aves, Mammalia, and Reptilia). 
By
Fort Collins Science Center

Size distribution and reproductive data of the invasive Burmese python (Python molurus bivittatus) in the Greater Everglades Ecosystem, Florida, USA, 1995-2021

This dataset contains morphometric information from Burmese pythons collected from an invasive population in southern Florida between 1995-2021. Scientists from the U.S. Geological Survey and the National Park Service curated this dataset as a repository for records of Burmese pythons found on or nearby federal lands in southern Florida, including Everglades National Park, Big Cypress National Pre
By
Fort Collins Science Center

Hatchling Growth Experiment Dataset from Invasive Burmese Pythons Captured in 2015 in Southern Florida

This dataset contains information about 58 hatchling Burmese pythons collected in 2015 from an invasive population in southern Florida. These hatchlings were used in an experiment that assessed the effects of food availability, clutch, and sex on their growth in captivity. The hatchlings were collected as eggs from the nests of two wild pythons, assigned to High or Low feeding treatments, and thei
By
Fort Collins Science Center
Burmese python hatchling
Burmese python hatchling
Burmese python hatchling
Burmese python hatchling

Burmese python hatchling

Burmese python hatchling

Non-native Burmese pythons have established a breeding population in South Florida and are one of the most concerning invasive species in Everglades National Park. This photograph is of a Burmese python hatchling

By
Ecosystems, Fort Collins Science Center, Communications and Publishing
Burmese python hatchling

Burmese python hatchling

Burmese python hatchling

Non-native Burmese pythons have established a breeding population in South Florida and are one of the most concerning invasive species in Everglades National Park. This photograph is of a Burmese python hatchling

By
Ecosystems, Fort Collins Science Center, Communications and Publishing

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

Burmese pythons (Python molurus bivittatus) are native to southeastern Asia, however, there is an established invasive population inhabiting much of southern Florida throughout the Greater Everglades Ecosystem. Pythons have severely impacted native species and ecosystems in Florida and represent one of the most intractable invasive-species management issues across the globe. The difficulty stems f
Authors
Jacquelyn C. Guzy, Bryan G. Falk, Brian J. Smith, John David Willson, Robert Reed, Nicholas Aumen, Michael L. Avery, Ian A. Bartoszek, Earl Campbell, Michael Cherkiss, Natalie M. Claunch, Andrea Faye Currylow, Tylan Dean, Jeremy Dixon, Richard M. Engeman, Sarah Funck, Rebekah Gibble, Kodiak C. Hengstebeck, John S. Humphrey, Margaret Hunter, Jillian Josimovich, Jennifer Ketterlin Eckles, Michael Kirkland, Frank J. Mazzotti, Robert A. McCleery, Melissa A. Miller, Matthew F. McCollister, M. Rockwell Parker, Shannon E. Pittman, Michael R. Rochford, Christina Romagosa, Art Roybal, Ray W. Snow, McKayla M. Spencer, Hardin Waddle, Amy A. Yackel Adams, Kristen Hart
By
Ecosystems Mission Area, Fort Collins Science Center, Pacific Island Ecosystems Research Center, Wetland and Aquatic Research Center

Egg retention in wild-caught Python bivittatus in the Greater Everglades Ecosystem, Florida, USA

Retention of eggs in oviducts beyond the normal oviposition period is a common problem for captive reptiles, but the occurrence of egg retention in wild populations is largely unknown. The Burmese python (Python [molurus] bivittatus; Kühl 1820) is an oviparous snake native to south-eastern Asia that is now established in southern Florida. From 2011–2019, invasive Burmese pythons were opportunistic
Authors
Gretchen Erika Anderson, Frank N. Ridgley, Jillian Maureen Josimovich, Robert Reed, Bryan G. Falk, Amy A. Yackel Adams, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Face-off: Novel depredation and nest defense behaviors between an invasive and a native predator in the Greater Everglades Ecosystem, Florida, USA

We describe several photo-documented novel interactions between intraguild predators in southern Florida—the native bobcat (Lynx rufus) and the invasive Burmese python (Python bivittatus). Over several days we documented a bobcat's depredation of an unguarded python nest and subsequent python nest defense behavior following the return of both animals to the nest. This is the first documentation of
Authors
Andrea Faye Currylow, Matthew F. McCollister, Gretchen Erika Anderson, Jillian Maureen Josimovich, Austin Lee Fitzgerald, Christina M. Romagosa, Amy A. Yackel Adams
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Agkistrodon conanti (Florida Cottonmouth) and Python bivittatus (Burmese Python). Diet and Predation

Python bivittatus is established in the Greater Everglades Ecosystem in southern Florida, USA. Documented predators on pythons in Florida include Alligator mississippiensis (American Alligator; Snow et al. 2006. Herpetol. Rev. 37:81–81), Drymarchon couperi (Gulf Coast Indigo Snake; Andreadis et al. 2018. Herpetol. Rev. 49:341–342), Lynx rufus (Bobcat; McCollister et al. 2021. Southeast. Nat. 20:N5
Authors
Ian A. Bartoszek, Gretchen Erika Anderson, Ian Easterling, Jillian Maureen Josimovich, Alex Furst, Frank N. Ridgley, Austin Lee Fitzgerald, Amy A. Yackel Adams, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

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

Identifying which environmental and genetic factors affect growth pattern phenotypes can help biologists predict how organisms distribute finite energy resources in response to varying environmental conditions and physiological states. This information may be useful for monitoring and managing populations of cryptic, endangered, and invasive species. Consequently, we assessed the effects of food a
Authors
Jillian Maureen Josimovich, Bryan G. Falk, Alejandro Grajal-Puche, Emma B. Hanslowe, Ian A. Bartoszek, Robert Reed, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Identifying negative sentiment polarity in the Judas technique

In the context of conservation science and management, the Judas technique refers to outfitting an animal (a Judas animal) with a radio transmitter or other identifier so that its movements can be tracked to locate conspecifics. Although this term is commonly used, some consider it offensive due to historical associations of the word Judas with anti-Semitic sentiments. Thus, the term has a negativ
Authors
Austin Lee Fitzgerald, Jillian Maureen Josimovich, Charlotte J. Robinson, Robert Reed, Andrea Faye Currylow
By
Ecosystems Mission Area, Fort Collins Science Center

Native mammalian predators can depredate adult Burmese Pythons in Florida

Invasive predators are of conservation concern because they contribute to species declines and extinctions worldwide. Interactions of native fauna and invasive predators can be complex, but understanding these relationships can guide management and restoration. Observations of these interactions are especially important for invaders with low detectability like Python bivittatus (Burmese Python) wh
Authors
Matthew F. McCollister, Jillian Maureen Josimovich, Austin Lee Fitzgerald, Deborah K. Jansen, Andrea Faye Currylow
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center

Using enclosed Y-mazes to assess chemosensory behavior in reptiles

Reptiles utilize a variety of environmental cues to inform and drive animal behavior such as chemical scent trails produced by food or conspecifics. Decrypting the scent-trailing behavior of vertebrates, particularly invasive species, enables the discovery of cues that induce exploratory behavior and can aid in the development of valuable basic and applied biological tools. However, pinpointing be
Authors
M. Rockwell Parker, Andrea Faye Currylow, Eric A. Tillman, Charlotte J. Robinson, Jillian Maureen Josimovich, Isabella M.G. Bukovich, Lauren A. Nazarian, Melia G. Nafus, Bryan M. Kluever, Amy A. Yackel Adams
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
Next Generation of Women in Science

Next Generation of Women in Science

As part of International Day of Women and Girls in Science, Fort Collins Science Center scientists volunteered to pass along personal and professional...

Read Article
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