The battles that burrowing owls and gopher tortoises are facing on FAU’s preserve
Stepping away from the hustle and bustle of everyday student life, surrounding Florida Atlantic’s Boca Raton campus holds a glimpse of nature. Behind the football stadium on the Tortuga trail and surrounding dorms is a 95-acre preserve dedicated to the conservation of the university’s mascot, the burrowing owl and gopher tortoises.
Both species are on the state of Florida’s designated threatened species list per the Florida Fish and Wildlife Conservation Commission (FWC). This means they are native to the state and have experienced a rapid decline in their numbers, but not to the level of being endangered.
In 1971, the Audubon Society, a non-profit organization for the conservation of birds, dedicated FAU’s preserve as an owl sanctuary, and to this day has continued to thrive as the university expands.
Florida Atlantic has produced and maintained owl habitats to support their nesting and breeding. The Boca campus is home to one of the largest populations of burrowing owls in its region and the owls have chosen the area because of its suitability for their habitat, explained FAU spokesperson Joshua Glanzer in an Oct. 2 email to the University Press.
“Their presence dates back decades and FAU has taken specific conservation measures to ensure their protection,” wrote Glanzer.
FAU works with Miller Legg, a consulting firm that offers environmental services such as visiting the Boca Raton campus bi-annually to conduct a protected species assessment to maintain the preserve.
In January, Miller Legg conducted its first assessment of the year by using foot traffic to ensure no destruction occurred to the preserve. This was the 29th assessment performed since January 2016 and took place over the course of one week.
Miller Legg workers saw 74 gopher tortoises and reviewed 423 burrows. They determined that 275 burrows were active, 41 inactive, 76 abandoned and 31 no longer considered burrows from the firm’s last assessment in September 2023.
During the January assessment, there were 22 burrowing owls directly sighted and 53 burrows with signs of occupancy, including 21 new ones from 2023. The burrows are dug between six and 10 feet into the ground and owls place their nests at the end.
Joshua Scholl, a biological sciences professor at FAU, conducts research focused on plants and their growth in different ecosystems and works with the gopher tortoises on campus.
“I attend the conservation committee meetings, which happen pretty regularly. I think right now, they’re scheduling them about every three to four months. Then during those meetings, we meet with Miller, [the] consulting company,” said Scholl.
During the meetings, the committee discusses new actions that need to be taken to keep up maintenance of the preserve with Miller Legg. In their last meeting this year, which occurs every three to four months, Scholl shared that they are preparing to conduct a mechanical clearing.
“They’re getting ready to do another mechanical clearing in the preserve, and that’s just meant to, ideally, simulate a fire — which is natural and helps to reduce the vegetation cover in an area. But we can’t have fires here because we’re right next to the airport,” said Scholl. “So the alternative is to mechanically clear some of the area, to open up the canopy[which is] just better for the tortoise.”
Scholl explained that regular fire maintenance ensures the gopher tortoises thrive. Fires produce a drier environment and help to control the canopy coverage in the habitat, like preventing overgrown vines and trees.
FAU utilizes different management techniques, such as controlled mowing of the grasses, to ensure that the preserve keeps the open and grassy environments that owls prefer.
“Optimal burrowing owl habitat includes areas with short or sparse vegetation, which allows them to easily spot predators and hunt for prey. They avoid dense vegetation or areas with tall grass, which can obstruct their vision and make it harder for them to detect threats,” wrote Glanzer.
The FWC describes burrowing owls as “pint-sized” birds, as they grow to a maximum height of nine inches and a wingspan of 21 inches. They’re adorned with white spots on their feathers and bright yellow eyes, which peak out to predators from the low grasslands that they call home.
Both the owls and gopher tortoises thrive in elevated dry lands and the main issue they are facing is habitat destruction.
“One of the problems with tortoises is that they love upland habitats and humans do too. We don’t like to build houses in the swamp. We like upland, dry habitats to build structures on,” said Scholl. “There’s this conflict between we need more space to build and that space is also occupied by these species that are dwindling.”
But habitat destruction isn’t the only danger that the two species are battling; they also have to deal with external predators.
Gopher tortoises are put in harm’s way by diseases and the local coyotes, “especially for the juvenile and hatchlings,” Scholl explains. He suspects that adult tortoises are able to resist the predation of a coyote, and in his four years at FAU there have been no attacks recorded.
The tortoises’ soft shells leave them at risk of predation from the raccoons that are scattered across FAU’s Boca campus.
Another species in South Florida is iguanas, an invasive species that arrived to the United States as stowaways on boats. Over 1.14 million iguanas were imported to the U.S. in 1995 as a result of the booming pet industry. When people realized that iguanas don’t make ideal pets, they began to discard them in the wild, which led to the spread of their population.
Iguanas can be spotted all across FAU’s campus and there’s an abundance of them present in the part of the preserve behind FAU’s football stadium.
South Florida native Daniel Say has witnessed the impact that iguanas are having on native species. He founded his Florida Iguana Specialist company five years ago, the business has blossomed out of Boca Raton and he serves the community to combat the invasion of iguanas.
Just like the tortoises and owls, iguanas too share a love for digging holes which presents an issue for the state-designated threatened species. Say explains how iguanas dig holes to lay a nest and sometimes they’ll build a fake one to serve as a decoy for other animals.
“They’ll definitely take an opportunity where they find a hole and go in there…They dig further in past where the normal place of the owl would place their eggs and I feel like as soon as they get in there, they’re definitely damaging the nest and the eggs,” said Say.
Even though iguanas are primarily herbivores, they’ve been known to eat eggs of native species. Say believes that is another issue the preserve species could be facing.
According to Scholl, a graduate student in the biology department is working on researching iguana consumption of gopher tortoises.
In Scholl’s classes, they go to the preserve to “explore plant characteristics and traits.” When they go out, they think of the plants and organisms that make up the biological community of the preserve. The information is taken in and can be used to form conclusions about the gopher tortoises having a proper food supply.
“They seem to be most enjoying the grass, grassy pasture out there next to lot five, because there’s ample foraging, so ample food for them…They’re pretty general in their diet, so they’ll eat just about anything they can access from cacti to fruits to grass,” said Scholl.
Through class efforts and external sources, Florida Atlantic is taking the appropriate steps to maintain the preserve. By monitoring the numbers of burrows and food levels, they are fostering growth for the threatened species.
Megan Bruinsma is the Sports Editor for the University Press. For more information regarding this or other stories email her at mbruinsma2022@fau.edu or DM her on Instagram @megan_bruinsma or Twitter(X) @MeganBruinsma.