Staff | Research Associates

George D. Gann, Chief Conservation Strategist, Acting Director

A founder of IRC, George is responsible for IRC's core Regional Conservation Models program, and contributes to national and international outreach on behalf of IRC. George has spent the last 40 years working on the conservation of rare plants, the restoration of ecosystems and a host of other conservation and sustainability issues. He has played a leadership role in a number of organizations including IRC, the Society for Ecological Restoration, the Florida Native Plant Society and the Tropical Audubon Society, and has received a number of awards for his conservation work. Originally from South Florida, he attended the University of Colorado Boulder, where he received a B.A. with distinction in International Affairs and Environmental Conservation. He has traveled widely in Latin America, as well as Europe, Asia and Australia. In addition to his other roles, George is currently Acting Director of IRC.

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Cara Abbott, MSc, Education & Outreach Coordinator

Cara joined IRC in the summer of 2015 as the new Education and Outreach Coordinator and served as Program Manager from 2017-2018. She is responsible for organizing and implementing volunteer events, providing educational talks and programs, managing IRC social media, and overseeing administrative and programmatic functions. A native of northern Virginia, Cara graduated with a Bachelor’s Degree in Environmental Biology with Teacher Licensure in 2012. As an undergraduate, she worked as a research assistant for an ongoing study on the federally threatened Peaks of Otter Salamander (Plethodon hubrichti). Cara then moved to South Florida where she earned a Master's Degree in Environmental Science from Florida Atlantic University in the summer of 2015. Her thesis research focused on the effects of sea level rise on the Black needle rush (Juncus roemerianus) grown in a high nutrient environment. Cara also teaches biology courses for a Broward County homeschool enrichment program and volunteers with the Sea Turtle Conservation League of Singer Island.
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J. Carlos Trejo Torres, Ph.D., Senior Botanist

A native of the Mexican Yucatan, Carlos is responsible for IRC’s program in the Yucatan and also plays a primary role in our work in Puerto Rico and elsewhere in the Caribbean. His expertise is in biogeography, plant taxonomy, the study of vegetation types, and the regional history of botanical science. He has a focus on rare, endemic, and poorly known plant species. He is also deeply interested in disseminating botanical knowledge to the public, and the use of native plants in gardening and landscaping. His research and findings have been featured in newspapers, on radio, and in TV programs in Puerto Rico, the Yucatan, and the Canary Islands. Carlos has three degrees in biology - an undergraduate degree from Universidad Autanoma de Yucatan (1993), a Master's degree from the University of Puerto Rico, Rao Piedras (2002), and a Doctorate from the Centro de Investigacian Cientafica de Yucatan (2013).


Samantha Gabriel, Administrative Assistant

Samantha joined IRC as the Administrative Assistant in June of 2017. She found IRC through a temp agency recruiter from Ultimate Staffing and is now a full-time, permanent employee. She is responsible for office administration, uploading new photos of plant species onto the website, updating the formatting of the website, uploading original data sheets for public access, editing reports, and so on. She graduated from Barry University in Miami with a Bachelor's degree in both Psychology and Fine Arts in the Fall of 2015. Although she did not major in the Environmental Sciences, she has a great appreciation for nature and wildlife.

Michelle Smith, Field Biologist

Michelle joined IRC in January of 2018 as a field biologist. She has her Bachelor’s Degree in Biology and Environmental Studies from Florida State University. Michelle gained her botanical experience in the Rocky Mountains of Colorado, the Atlantic Coastal Plain of Georgia and Florida, and in the high-desert, sagebrush-steppes of eastern Oregon. More recently, Michelle has gained experience in north and south-central Florida conducting rare plant and non-native (invasive, exotic) plant surveys, gopher tortoise surveys, and vegetation monitoring surveys. She has contributed county records for a few plants just last year. Michelle’s interests include botany, dendrology, fire ecology, habitat restoration (land management), and photography.

Hans van der Heiden, Crew Leader

Growing up in an environmentally conscious family, Hans developed a deep appreciation for the natural world. As a teenager, he helped his father collect data in the Everglades, worked with aquatic snakes at Jonathan Dickinson State Park, and volunteered at a local community garden. After graduating Broward College with an AA degree, he moved to the Jones Center @ ICHAUWAY for a year. During that time he participated in telemetry, small mammal trapping, and deer surveys. Hans moved back down to South Florida to work as an invasive control crew leader for IRC.

Sandy Koi, MSc, Entomologist

Sandy is IRC's resident Entomologist, whom we share with other like-minded organizations in South Florida. She earned an MSc in Entomology from the University of Florida and has a BSc in Environmental Science and Biology from Nova Southeastern University. Her scientific publications revolve around the object of her thesis, the Atala butterfly (Eumaeus atala), an imperiled South Florida species that she has been studying since 2001. Sandy currently spearheads an assisted relocation project for the Atala butterfly from eruption sites into suitable new sites in southeastern Florida. She actively coordinates butterfly surveys for organizations such as the North American Butterfly Association (NABA), Florida Natural Areas Inventory (FNAI) and IRC. She is a contributing member of the Imperiled Butterfly Working Group (IBWG), under the authority of the Florida Fish and Wildlife Conservation Commission, and a founding member of the Miami Pine Rocklands Coalition, a non-profit dedicated to protecting this globally imperiled ecosystem. Many of her photographs and plant information about South Florida butterfly host and nectar plants grace the national NABA website and she is a frequent speaker at local organizations in Florida, including Butterfly Days at Fairchild Tropical Botanic Garden and the Southern Lepidopterists Society.

Research Associates

Steven E. Green

Steve is an ecologist with Mitigation Resources L.L.C. based in Clermont, Florida where he conducts ecological site assessments and designs, oversees and implements vegetation monitoring programs on mitigation bank sites from South Florida to the Panhandle. Steve joined IRC as a Biologist in the summer of 2005 as a part of IRC's restoration crew for the USFWS Private Stewardship Grant Program, controlling exotic species on privately owned pine rocklands. Steve participated in, or managed a myriad of other IRC projects including long-term rare plant monitoring and surveys in Everglades National Park; status surveys of threatened, endangered and candidate plant species for the USFWS; floristic inventories for Miami-Dade County Environmentally Endangered Lands Program and Lee County Parks, and; exotic plant surveys and mapping for FNAI. Steve moved to Orlando in the fall of 2008 and assumed a new roll for IRC as a Research Associate. In this capacity, Steve has been disseminating the wealth of vascular plant knowledge he has amassed during his time at IRC and has instructed grass identification and invasive plant identification workshops for local CISMAs including the Central Florida CISMA, the Heartland CISMA and the Lake County CISMA.


Kirsten N. Hines, MSc

Kirsten Hines is a writer, photographer and environmental educator. With a master’s degree in biology, she has studied tropical frogs, South Florida plants and animals, and Bahamian iguanas, and is a member of the IUCN Iguana Specialist Group. Kirsten currently is a Research Associate at IRC and is coauthor of our Natives for Your Neighborhood, the online plant conservation resource. Her award-winning photography has appeared in numerous publications, websites, and brochures and is featured in the Birds of Fairchild, and Attracting Birds to South Florida Gardens, which she co-authored. She also is coauthor of Images of America: Key Biscayne. Through her writing and photography, she aims to expose the intricacies of the natural world, to lure readers and viewers into the lives of plants and animals. She attributes her interest in South Florida’s native plants and the re-greening of the urban corridor (both championed in her Attracting Birds to South Florida Gardens book) to her experiences at IRC. More of her work can be seen at

James Johnson, MSc

Growing up on one of Georgia's oldest farms, James developed a deep appreciation and a never-ending curiosity for the natural world. His Grandfather and Father impressed upon him the practice of good stewardship of the land and the conservation of its natural resources, and this wisdom guided him into his current field of work in environmental conservation.

James graduated with honors from Armstrong Atlantic State University (AASU) in Savannah, Georgia with a degree in biology. While at AASU he worked as a biological research assistant on a project aimed at better understanding the metabolic pathways of epiphytic Bromeliads. James then came to South Florida in 2009 to pursue the life of a graduate student at Florida Atlantic University and found himself at home in the environment of the Everglades and the costal landscape.

While at FAU, James was involved in many research endeavors spanning from the peat bogs in northern Alberta, Canada, to the tree islands of the Everglades. He graduated with a master's degree in 2012 after completing a thesis titled Estimating the Vulnerability of Everglades Peat to Combustion. During his time in graduate school, James became became very familiar with the Greater Everglades ecosystem and joined the team at ICR in November 2012 as a field biologist to continue the ongoing conservation efforts in South Florida and beyond. In 2014 James moved back to Georgia to begin a Ph.D. program.

Jimmy Lange

Jimmy graduated with honors from the University of Florida with a Bachelors of Science in Environmental Science. He began his research career studying under the guidance of graduate mentor Jenny Schafer in the Mack Ecosystem Ecology Lab. He went on to join the Plant Ecology Lab at Archbold Biological Station where he assisted on a number of research projects including demography of several rare plant populations, effects of fire frequency on scrub habitat, experimental restoration of scrub habitat on reclaimed pasture, and plant community structure and composition of differing scrub management regimes. He then began work at the Michigan Tech Research Institute where he conducted ground-truthing surveys of Great Lakes wetland plant communities and worked to generate a map of both the current and possible future extent under modeled hydrologic scenarios of Phragmites australis. Jimmy attended graduate school at Florida Atlantic University where he studied combined legacy impacts of invasive species Melaleuca quinquenervia and management practices on plant communities in the northern Everglades. Jimmy joined IRC in 2014 as a field biologist then as a research associate. He is currently a field botanist on the South Florida Conservation Team at Fairchild Tropical Botanic Garden, where he continues to focus on rare plant conservation and habitat management. He also currently serves on the board of directors for the Florida Exotic Pest Plant Council, of which he is the current chair elect.

Sarah Martin

Hailing from the wilds of New Jersey, Sarah received her degree in Environmental Studies and French from Seattle University in 2005. She has also interned and studied at The University of Pennsylvania's Morris Arboretum, studied and worked in Belize and France, worked as a deck hand and environmental educator on a restored oyster schooner, and as a gardener at Seattle University's organic, sustainable campus garden. Before joining IRC, Sarah worked with the Florida Park Service, The Nature Conservancy, the US Fish & Wildlife Service and other agencies in South Florida with a conservation focus. She has worked in a number of regional ecosystems including cypress swamp, scrub, pine flatwoods, maritime hammock, freshwater marsh, coastal strand and the beautiful riverine systems of Florida's first federally designated Wild and Scenic River, the Loxahatchee. Her primary responsibilities revolved around invasive exotic species removal, prescribed fire, installing native plants, water quality testing, species monitoring, volunteer coordination and environmental outreach and education. Sarah joined IRC in late 2010 as the Program Coordinator for our Pine Rockland Initiative and later was in charge of IRC's Ecological Restoration & Management Program. She stepped into a Research Associate position in 2015.

Maha Nusrat

A native of West Palm Beach, Florida, Maha was the Pine Rockland Initiative Coordinator and a crew leader in IRC's Ecological Restoration & Management program. She was inspired from a very young age to be engaged in activities dealing with ecological studies, restoration, and environmental education. In 2011, she moved to Miami to pursue her Bachelor's of Science in Biology at Florida International University. After graduating in 2013 from FIU she became involved in projects studying the pollination biology of flowering plants in the Apocynaceae family and the fragmentation of the pine rocklands on the Miami Rock Ridge. She also interned at the environmental education department at Fairchild Tropical Botanical Garden to help ensure that future generations develop an appreciation for and interest in their natural surroundings. She joined IRC in April 2016 and continues to fuel her passion for ecological restoration projects. In her spare time, she helps her dad with his gardens, rollerblades around town, enjoys the beach, and has fun trying new coffee shops around town. She stepped into a Research Associate position in 2018.

Sonali Saha, Ph.D.

An all-around lover of plants, Sonali is particularly interested in how plant structure and function affects their ecological distribution. She's excited about how this information can be applied to restoration planning to maintain appropriate plant communities in natural landscapes. A native of India, Sonali received her Ph.D. from the University of Illinois. She has worked with a variety of plant taxa in different ecosystems including subtropical deciduous forests of the Indian subcontinent, subtropical forests of Argentina, the Florida scrub ecosystem and most recently, pine rockland habitats in the Everglades. Sonali served for several years as IRC's Everglades Vegetation Biologist, a cooperative post with Everglades National Park. Saha co-authored a report titled Sea level rise and South Florida coastal forests published in the journal Climate Change. She is currently working was a visiting faculty member at the University of Miami and as Adjunct Faculty at Touro College, South.

Christina Stocking

Originally from the farmlands of Missouri, Christina grew up with a deep respect for nature but a yearning for the big city life. At the age of 21, she endeavored on a trip to make the dream of big city living a reality and moved to Miami. After 8 years in the field of accounting, she began to miss her connection to nature and decided to return to school to pursue a Bachelor's of Science in Biology at Florida International University. In 2010, she left accounting for good to fully focus on her new love, botany. Armed with her new found plant knowledge and her reliable accounting skills she was chosen for an internship at Fairchild Tropical Botanic Garden as the Conservation Research/Plant Records Intern in 2011. During the year-long internship she contributed to the floristic and conservation research being conducted here in South Florida and abroad including the Cockpit Country of Jamaica, the Caribbean Basin and Indonesia. She also contributed to the maintenance of plants records for the garden including the integration of the American Orchid Society's orchid collection into Fairchild's Living Collection. After the internship ended and her bachelor's degree completed, Christina started working for the IRC in 2012 helping to maintain the databases the fuel the many floristic inventories that the IRC has to offer. In addition to database management she also assists in floristic and taxonomic research. With a thirst for knowledge she strives for excellence by continuing her education. She is an ISA Certified Arborist and a Florida Master Naturalist.

Craig van der Heiden, Ph.D.

Originally from Zimbabwe in southern Africa, Craig left behind a successful career in ecotourism and entered graduate school at Florida Atlantic University. In 2005, he completed his Masters degree, which focused on modeling the habitat requirements of reintroduced black rhino in the woodland savannas of Malawi. In 2012, he received his Ph.D. in Integrative Biology from FAU for work on the distribution dynamics of crayfish populations in the Florida Everglades. A versatile and experienced manager of multifaceted projects, Craig brought knowledge of business management and complex logistics as well as the science of conservation biology when he joined as Assistant Director of IRC in 2012. In 2013, he was promoted to the role of CEO.

In 2017, Craig took a position as Wildlife Director for the Miccosukee Tribe of Indians, but also remains on as Research Associate at IRC.

Steven W. Woodmansee

A South Florida native, Steve earned a B.S. in Biology from the University of Miami in 1996. Prior to IRC, he worked for two years as a research assistant at Fairchild Tropical Botanic Garden (FTBG). His duties included vascular plant identification, vegetation mapping and monitoring, and rare plant research. He also served as a naturalist at the Deering Estate at Cutler in Miami for three years. While at the University of Miami, he served as a field assistant to Dr. Carol Horvitz, helping conduct post-hurricane vegetation monitoring in Miami-Dade County. In 1997, he joined IRC assisting with the Floristic Inventory of South Florida, the results of which were published as the book Rare Plants of South Florida : Their History, Conservation, and Restoration (Gann, Bradley & Woodmansee 2002). Since then, Steve has participated in many IRC projects and contributed to a number of exciting botanical discoveries, including a significant new population of an endemic cactus in Biscayne National Park (Bradley & Woodmansee 2002). He has also managed several IRC projects including the floristic inventories of conservation areas in Lee, Martin and Monroe counties. He has deposited over 1400 herbarium specimens at FTBG, including additions to the South Florida flora, and many new county records. Since 2000, he has served as co-chair of the Miami-Dade Native Plant Workshop (NPW), a free program which educates the public in plant identification techniques. He has also served in several leadership positions in the Florida Native Plant Society, including President. Steve is now an active nurseryman, focusing on native plants.