Sanctuary Staff

Sanctuary staff standing at the front rail of R/V MANTA


G.P. Schmahl
Sanctuary Superintendent
(409) 356-0383

G.P. Schmahl has been the manager of Flower Garden Banks National Marine Sanctuary since March 1999. Prior to that he served for eight years as the Lower Keys Regional Manager of Florida Keys National Marine Sanctuary in Key West, Florida.

As sanctuary manager, he is involved with a broad array of Marine Protected Area management issues including research, education and resource protection. Since obtaining a graduate degree in Zoology from the University of Georgia, G.P. has held a variety of positions relating to marine research, coastal management, resource planning and environmental regulation. His primary interest is the ecology and management of coral reefs and associated ecosystems, and he has a specific interest and expertise in the biology and ecology of marine sponges.


Irene Olivares-Arthur
Administrative Program Specialist
(409) 356-0393

Irene Arthur joined the Flower Garden Banks National Marine Sanctuary team in 2001. As the sanctuary's Administrative Program Specialist, she is responsible for providing primary program support in the areas of administration, budgeting, procurement and fiscal planning for the sanctuary.

Irene develops annual budgets, tracks and verifies budget status, prepares periodic status reports, analyzes and manages fiscal year procurement actions and prepares acquisitions for technical contract services. She also manages administrative record-keeping and prepares travel arrangements for sanctuary staff. Irene is a 1988 graduate of Texas A&M University having earned a BS in Psychology and Accounting.


Shelley Du Puy
Education & Outreach Coordinator
(409) 356-0382

Shelley Du Puy joined the Flower Garden Banks National Marine Sanctuary team in 1994. As the sanctuary's Education & Outreach Coordinator, she is responsible for coordinating all education, outreach, public relations and non-research volunteer activities for the sanctuary.

Shelley holds a Bachelor of Science degree in Marine Science from Texas A&M University at Galveston and has over 30 years of experience with NOAA in areas ranging from fisheries data collection to wetlands conservation to environmental education. While working as a Fisheries Biologist, Shelley observed that many people had little or no concept of how activities on land and in coastal areas affected the larger ecosystem. This was the motivating factor in her decision to focus her career on the education aspects of natural resource management.

Kelly Drinnen
Education & Outreach Specialist
(409) 356-0388

Kelly Drinnen joined the Flower Garden Banks National Marine Sanctuary team in August 2004. As Education Specialist, she is responsible for public communications such as the sanctuary website, social media, email lists and informational flyers and brochures. She also conducts workshops and presentations.

Prior to working for the sanctuary, Kelly worked in informal science education at Moody Gardens and Sea World of Florida, as well as two years as a 4th grade teacher in South Houston. Kelly is also part of the sanctuary dive team.


Melissa Mathes Trede
Vessel Operations Coordinator
(409) 356-0395

LTJG Melissa Mathes Trede, a NOAA Corps Officer, joined Flower Garden Banks National Marine Sanctuary in February 2019. Prior to this assignment, she worked at headquarters in Silver Spring, MD for two years with the National Weather Service, in the Undersecretary’s office, and at the Office of Marine and Aviation Operations.

She also served two years aboard NOAA Ship GORDON GUNTER as a junior officer where she earned her officer of the deck qualification and 100 ton Captain’s license. Melissa graduated magna cum laude from Texas A&M at Galveston with a Bachelor’s degree in Marine Biology. The VOC position is a great opportunity to combine her professional experience with her interest in marine sciences and conservation.

Justin Blake (Affiliate)
Captain, R/V MANTA

Justin Blake, a 500-ton master captain and U.S. Coast Guard registered boat builder, joined Flower Garden Banks National Marine Sanctuary in May 2018. Justin has a Bachelor degree from the University of Florida where he also earned his advanced certification in scuba diving. He is a member of several sailboat racing teams and in 2013 finished the Transpacific Yacht Race from Long Beach, California to Honolulu, Hawaii. Born and raised in Florida and living for a decade in Southern California, Justin enjoys many watersports including surfing, kiteboarding & wakeskating. He has invested his entire life in the marine industry and enjoys working to help it be here for future generations to enjoy.


Emma Hickerson
Research Coordinator
(409) 356-0390

Emma was born in Sydney, Australia, and moved to Texas in 1984. She was initially trained as a diver in 1990, and has since logged more than 1250 dives. She has been the Research Coordinator at Flower Garden Banks National Marine Sanctuary since 1997. During this time she has contributed to over 40 scientific publications relating to the marine environment.

Emma served as the Unit Diving Supervisor for the sanctuary until 2017, and supervised over 5000 dives during more than 155 sanctuary research cruises. In 2014, she was inducted into the Women Divers Hall of Fame in recognition of her accomplishments in this arena.

Emma has coordinated and led research utilizing scuba, remotely operated vehicles, and manned submersibles. She is not only passionate about studying the marine environment, but also interpreting science through multimedia, including photography, videography and art.

Raven Blakeway (Affiliate)
Research Specialist
(409) 356-0384

Raven (Walker) Blakeway joined the Flower Garden Banks National Marine Sanctuary staff in 2016. She obtained her B.S. in Marine Sciences and M.S. in Marine Biology at Texas A&M University at Galveston and is currently pursuing her PhD in Marine Biology. Raven has done research in tracking consumer-driven declines in historical marine animal populations of the Chesapeake Bay, but currently works on developing consumer markets for the invasive lionfish in the Caribbean Sea and Gulf of Mexico. As a sanctuary research specialist, she provides support to various research projects, as well as the ongoing long-term monitoring program. She is also a NOAA diver.

John Embesi (Affiliate)
Research Specialist
(409) 356-0385

John Embesi joined the Flower Garden Banks National Marine Sanctuary team in 2009. As a Research Specialist, his responsibilities include continuing the long-term monitoring of the banks within the sanctuary and providing support to the FGBNMS research team and partners on various projects. Prior to joining the FGBNMS team, he spent ten years as a Research Specialist and Diving Safety Officer with the Texas Parks and Wildlife Department Artificial Reef Program.

Michelle Johnston
Research Ecologist
(409) 356-0392

Michelle joined the Flower Garden Banks National Marine Sanctuary team in 2011. As a research ecologist and NOAA science diver, she manages the sanctuary’s long-term coral monitoring project and battles invasive lionfish! Michelle has previously been a scuba dive team member at the Living Seas Aquarium in Florida, a sea turtle field biologist in South Carolina, as well as a marine educator and surf instructor in North Carolina, Australia, the Bahamas and Hawaii.

Michelle's academic studies started at UNCW in marine biology where she rehabilitated sick and injured sea turtles, and continued at the University of South Carolina where she completed her M.S. and Ph.D. in Environmental Health Science researching bacterial pathogens in coastal waters. After graduate school, Michelle was awarded a NOAA Sea Grant Knauss Marine Policy fellowship with NOAA’s Office of National Marine Sanctuaries.

Jimmy MacMillan (Affiliate)
Research Specialist
(409) 356-0389

Jimmy MacMillan began volunteering as a diver with Flower Garden Banks National Marine Sanctuary in 2016 and joined the research team in July 2017 as the water quality specialist. His job duties include maintaining water quality instrumentation, running quarterly water quality cruises, assisting in mooring buoy installations and supporting long-term monitoring and research. Jimmy has over 10 years of experience supporting scientific and engineering projects and specializes in remote and difficult environments. He holds a B.S. in biology from The University of Texas, Austin.

Kelly O'Connell (Affiliate)
Research Specialist
(409) 356-0387

Kelly O'Connell joined the Flower Garden Banks National Marine Sanctuary team in 2018. Though originally from Chicago, she graduated from University of South Florida with a B.S. in biological science where she studied Symbiodinium-associated microbial communities and their role in coral reef resilience. She obtained her master's degree from the University of Miami where she investigated the association of water temperature anomalies with measurements of white plague in Orbicella coral species.

Prior to joining the FGBNMS team, Kelly assisted with long-term monitoring and data management at the National Park Service South Florida Caribbean Network. There she used decades of monitoring data to quantitatively define disease outbreak. After graduate school, Kelly worked as a research technician performing coral and fish surveys with NOAA Southeast Fisheries under the National Coral Reef Monitoring Program in the Florida Keys and the U.S Virgin Islands. As a sanctuary research specialist, she assists with the long-term monitoring of FGBNMS reefs and provides support for data analysis and various other research projects. 

Marissa Nuttall (Affiliate)
Research Specialist
(409) 356-0391

Marissa joined the Flower Garden Banks National Marine Sanctuary research team in 2007. She manages the long-term monitoring program at Stetson Bank, supports mesophotic ecosystem research both within and around the sanctuary, and leads GIS support for research and management activities. Marissa also serves as the Unit Diving Supervisor for the FGBNMS dive unit and has coordinated and led multiple research expeditions utilizing SCUBA and remotely operated vehicles. She is a graduate of Texas A&M University at Galveston and holds a M.Sc. in Marine Biology.

Sanctuary Advisory Council

Leslie Whaylen Clift (Affiliate)
Advisory Council Coordinator
(409) 356-0386

Leslie Whaylen Clift joined the Flower Garden Banks National Marine Sanctuary team in July 2015. As the Sanctuary Advisory Council Coordinator, she serves as the primary contact for the Advisory Council and facilitates all aspects of council-related activities. Leslie also assists with the sanctuary expansion review process. Leslie began diving in the sanctuary in the 1990s, as a volunteer fish surveyor while working for the state of Texas as an Aquatic Scientist. After moving to the Florida Keys, she returned occasionally to FGBNMS to lead and instruct groups of REEF (Reef Environmental Education Foundation) divers and conduct fish assemblage surveys. Leslie returned to Galveston in 2012.