CU Boulder undergraduate joins an innovative effort to rescue dying coral reef and bring it back from the brink of extinction

In 2014, the northernmost tip of the Florida coral reef tract began to turn white.

These corals were infected by Stony Coral Tissue Loss Disease (SCTLD), which destroys the species’ soft tissue. To date, the infection has killed several million Caribbean corals and is regarded one of the deadliest recorded coral-disease epidemics.

To stave off the reef’s extinction, a group of government agencies developed a plan to remove healthy coral specimens untouched by SCTLD and move them to land-based “arks.” Broomfield’s Butterfly Pavilion was asked to become one of these arks, holding some of the rescued corals because the staff had experience working with invertebrate species that do not have skeletal backbones.

Ty Engelke, who is an undergraduate at the University of Colorado Boulder, discovered what became called the Florida Reef Tract Rescue Project while watching a video blog about the effort.

“It was beyond exciting to know that there were these immaculate Caribbean corals right there (in Broomfield),” says Engelke, who is majoring in molecular, cellular and developmental biology. “I went and saw them in person and thought, ‘I need to find a way to be a part of this.’”

Engelke is a hobby aquarist who keeps large aquariums of fish. He hoped his experience would translate into a strong application for a competitive aquarist internship at the Butterfly Pavilion. At the time of his application, though, he did not have enough background with saltwater species and his first application was turned down.

“I was dejected because it was something I really wanted,” says Engelke. “In the grand scheme of things, it wasn’t something I was ready for.”

To strengthen his application, Engelke took courses in marine ecology, oceanography and limnology in fall 2020 and spring 2021. He also began keeping marine invertebrates and saltwater tanks. In summer 2021, he reapplied and earned the opportunity to volunteer with the Florida Reef Tract Rescue Project.

Getting to know corals with personalities

The project has one bio-secure display “tank” that holds around 250 gallons of water. Nineteen colonies of variously sized corals have nametags that describe the species and their place of origin—information that is registered with the Association of Zoos and Aquariums and Florida Fish and Wildlife Conservation Commission.

Engelke’s primary job is to clean filtration systems and the tank, ensuring the tank is working properly and tests water parameters in the lab. His favorite responsibility, though, is feeding the corals.

“Corals are animals and have personalities,” says Engelke. “You can have two corals who are the same species and are sitting next to each other, and one will eat a lot more than the other on some days and some days it won’t. It’s been fun over these last months to get to know them. I definitely have my favorites.”

The team has experienced success in the corals adapting to their new environments, but it was not always clear they would thrive in captivity. Engelke described one instance in which a coral was struggling, but it was not immediately clear why.

“One of the biggest challenges in caring for Caribbean Stony Coral is the lack of information about their requirements in captivity,” notes Engelke. “Not seeing progress and the coral doing well was a big test of patience for the better part of a month.”

Engelke’s supervisor, Sara Stevens, the Butterfly Pavilion’s aquatics manager, asked the team to step back and allow the environment to settle. The choice paid off, and the coral grew stronger.

“I learned patience and diligence vicariously from Sara—to be on the ball all the time,” says Engelke. “Now, all of the corals are much happier.”

Deepening his interest through flexible graduation requirements

At CU Boulder, Engelke has sought to learn more about marine biology alongside his major coursework in molecular, cellular and developmental biology. The College of Arts and Sciences requires undergraduates to complete 75 of their 120 credits outside of their major department, meaning Engelke could pursue his interests without fighting for placement in upper-division electives.

“The openness of the major allowed me to study marine life, oceanography and atmosphere studies while focusing on cell biology,” notes Engelke. “No one caused a big fuss, I felt welcome, and I didn’t have prerequisite hoops to jump through before taking upper division classes. It was nice to learn about something that I, really, just liked.”

Engelke plans to continue volunteering with the Butterfly Pavilion and is excited to meet challenges as his experiences with corals grows.

The Butterfly Pavilion committed to housing the corals for three years without funding, beginning in 2019. Because the corals continue to thrive, the pavilion is finalizing the installation of a new tank. Engelke anticipates that the requirements of caring for coral will rapidly change, and he will need to continue to build his expertise to keep up.

“It’s so cool to see what grand, combined effort has gone into this. There are so many people doing such amazing work,” says Engelke. “I'm honestly honored to be part of it.”