HRI Lecture Series - Dr. Fernando Calderon Gutierrez - "Scientific technical diving as a tool to conduct ecological studies on the subterranean estuary of the Yucatan Peninsula"

"Scientific technical diving as a tool to conduct ecological studies on the subterranean estuary of the Yucatan Peninsula"

DR. FERNANDO CALDERON GUTIERREZ
POSTDOCTORAL RESEARCH ASSOCIATE
TEXAS A&M UNIVERSITY-SAN ANTONIO

Subterranean estuaries are characterized by high levels of endemism and extreme conditions. However, few ecological studies have been conducted in these ecosystems due to the necessity of scientific cave diving techniques. For than 10 years ecological studies have been conducted in Cozumel Island and the Caribbean Coast of the Yucatan Peninsula, including biodiversity studies, faunal monitoring, environmental monitoring, and molecular ecology. As a result, we have:

1. Described seven new species of marine sponges,
2. Identified ecological patterns to explain the species richness and density in an anchialine cave,
3. Determined that the subterranean estuary is affected by meteorological events,
4. Detected that cave specialized species are more resilient to mortality events than populations of reef species inhabiting the caves, and
5. Found several cryptic species which have been widely misidentified in the past as a single species.

However, these findings would not have been possible without the use of technical techniques including cave diving, use of rebreathers, and decompression diving; as well as with the collaboration of local and international cave diving instructors, most of them involved in the original exploration and mapping of the caves under study. Collaboration with local and international cave divers has proven to be mutualistic. Researchers benefit from being introduced to caves of significant research interest, and their scientific dive safety is enhanced by the presence of a dedicated safety diver who is familiar with the caves being investigated. Meanwhile, local cave diving instructors have the opportunity to learn about the biological importance and conservation of the caves, providing them with information they can subsequently share with their students and tourist.

Fernando graduated with a B.S. in Marine Biology from Universidad Autónoma de Baja California Sur in La Paz, Mexico, where he also obtained his Master of Science degree. He later obtained his PhD in Marine Biology from Texas A&M University at Galveston. Currently, he is a Postdoctoral Research Associate at Texas A&M University – San Antonio. Fernando has been working on the biodiversity and ecology of aquatic groundwater ecosystems since 2011. His research activities have resulted in eight scientific publications and one book chapter. He has described seven species of cave endemic sponges, has characterized ecological patterns of aquatic groundwater cave community assemblages, and demonstrated how meteorological events can have direct impact to these ecosystems. His research was considered instrumental in the establishment of the first Mexican National Park to protect an underwater cave (El Aerolito). He was recently featured in the journal Nature, as well as the Netflix documentary Alien Worlds, and popular YouTube channels. Fernando is a commission member and Global/Regional Red List evaluator of an IUCN’s specialist group and is an active scientific / working diver for NOAA’s Flower Gardens Bank National Marine Sanctuary in the Gulf of Mexico. Fernando is also an AAUS Scientific Diving Instructor, and technical diver with extensive experience conducting research in open water and overhead environments.