Redlands Bat House
Around the corner from the primate troops at Monkey Jungle, past shade houses, container nurseries and a pot farm perfectly suited for funky old Redland, another very Florida thing has been erected on the former country retreat of a Miami pioneer: the world’s biggest bat house.
And the timing couldn’t be better for one of the most endangered mammals on the planet, the Florida bonneted bat.
If the new bat house at Patch of Heaven succeeds in attracting the trumpet-eared bats — and that’s a big if — it could help rewrite the fate of a species that has lost nearly all its natural habitat and now numbers in the hundreds.
“From all the stuff I’ve read, the bigger your bat house is, the better your chances of getting it inhabited,” said Fred Hubbard, a horticulturist and former high school science teacher who dreamed up the Indonesian-styled structure and planned Patch of Heaven’s elaborate gardens with his partner Roberto Del Cid for owner Bruce Chesney.
Even if it doesn’t work, the bat house could succeed at a larger mission: drawing attention to the plight of the bats and another effort under way by Zoo Miami to craft a rescue plan for bats forced to live in a continually changing urban environment.
“All of South Florida is developing so fast, so for this kind of species the city is the only thing they have. So that’s why it’s so important to understand how they’re adapting,” said Melquisedec Gamba-Rios, a tropical bat expert who started a three-year research project at the zoo last month.
Inspired by the nightly departure of a half-million bats from three bat houses at the University of Florida, the structure includes two stories under its soaring temple roof. A lower level holds roosts for common evening and Brazilian free-tailed bats like the ones inhabiting UF’s bat house for the last quarter-century and accustomed to living in crowded colonies. Upstairs is where the magic could happen: dozens of boxes specially designed for the larger, more solitary bonneted bats.
“According to the [UF] web site, they’re the biggest occupied bat houses in the world,” Hubbard said. “Our bat house is technically bigger. We’re trying to get the wording right on that.”
The bat house is also the first designed to accommodate the bonneted bat on such a grand scale, although the jury is still out on whether it will work.
“I went out there at the time it was just concrete posts and I was like, well, it’s high enough but they’ll need bigger chambers and we don’t know if they’ll co-occupy the space,” said Frank Ridgely, a wildlife veterinarian and head of conservation for the zoo and its bat efforts, who offered Hubbard design advice. “It’s an experiment. We’ll find out.”
Like panthers, key deer and other disappearing animals that once inhabited pine rocklands, bonneted bats were once plentiful in the open-canopied forest that grew across South Florida’s spiny ridge. The big bats’ thinner arms make them the fighter jet of the bat world, able to race at great speeds but less able to turn tight corners, making the airy forest a perfect place to feed on mosquitoes, moths and other bugs. The hollows in the tall pines also made perfect roosts for the high fliers.
But as the pineland disappeared, so did the bats. In 2013, when the U.S. Fish and Wildlife Service added them to the endangered species list, just a few hundred bonneted bats remained. The service was supposed to designate a critical habitat, which could further protect their range, but has yet to complete the process.
Their plight went largely unnoticed until they were discovered foraging over a golf course in Coral Gables in 2014, while, coincidentally, a battle was heating up over plans to build a Walmart-anchored shopping center on the last, biggest tract of privately owned pineland adjacent to the zoo.
The discovery by a Florida International University bat researcher sitting on her back patio near the golf course helped launch a bat squad with Bacardi-sponsored bat-watching parties. With her help, citizen scientists located a rare roost in the cracked barrel tiles of a dilapidated house two blocks from the greens, only the second wild roost ever found.
The work caught the attention of Ridgely, who had been working to restore pinelands around the zoo and studying the animals that live in the rare forest. A few months later, an orphaned baby bonneted bat was found, giving Ridgely an opportunity to study its habits more closely. In the years since, and countless hours of searching for roosts, he’s concluded their survival depends largely on understanding how they’ve adapted to city life.
“All the conflict for the species is happening here in Miami. If they’re out in a natural preserve, that’s fantastic, right? And we want to figure out what they need there. But rapid urbanization is going to take over most of their range,” he said.
Over the last five years, he gradually worked out a rescue plan with the help of Bat Conservation International, a Texas-based nonprofit. Using a recording device because he can’t hear them, he located foraging grounds. (Men and older folks often can’t hear them because the frequency is too high, he said.) He identified areas between Coral Gables and Homestead and located the best places to erect bat boxes with single roosts, and much less elaborate than Hubbard’s grand bat house, on government or other protected land, which required permitting because the bats are federally protected.
The boxes themselves were also a feat: Because so little is known about the bats, the design was based on the only known bat box to ever attract a bonneted bat on the west coast — and that was by mistake. The owner misunderstood instructions for assembling a standard box and made it bigger, Ridgely said. It was the design of this basic box, with bigger chambers for the larger bats, that helped guide the design of Hubbard’s.
“The strategy for [the U.S. Fish and Wildlife Service] for the whole rest of the state is protect the roosts because that’s where they’re going to be during the day, that’s where they’re going to raise their young and that’s where they’re safe. And that’s a great strategy,” he said. “But the urban [bonneted] bats we think are much different. And every bat that’s in a home is at risk every day.”
The boxes sit atop sturdy utility poles about 35 feet high and cost about $5,000 each, compared to the $188,316 spent for the Path of Heaven house. Bat Conservation, the Naples Zoo, U.S. Solar and Florida Power & Light helped pay for the 16 boxes. Bat Conservation staff also suggested hiring a bat biologist and helped persuade FPL to pay for Gamba-Rios’ position.
Among the questions they want to answer is where the bats are foraging. They seem to wind up in the same open spaces to feed, confirmed by Ridgely’s recordings of commuting calls and feeding buzzes. The recordings also suggested the bats may be concentrating west of Brickell, near busy Calle Ocho, where Ridgely rescued another injured bat.
“Do they forage high above the urban area or do they just roost there? It’s crazy,” Ridgely said. “They have a million roost options. That’s not the shortage. They’re adaptable. Maybe there are spots where they go to hunt food that are important open spaces and you know Miami — we just love to fill in open space.”
Existing research also suggests the bats breed year-round, which means rules governing when bats can be removed from buildings might not apply. Gamba-Rios said there are other factors, like streetlights, that might influence the bats’ habits.
The long-term strategy is to find safe spots, so numbers increase, and devise a playbook for bats and people to live together.
“We want people to love this bat. We want them to embrace it and take it as their special neighbor,” Ridgely said. “We don’t want this bat to become the face of don’t do this development. We want to find solutions where you co-exist.”
Of the 16 bat houses, five have so far been occupied, a significant feat so early in the project. The first male — males scout out roosts and then attract harems — arrived just three weeks after the zoo boxes were completed in August. The biggest number are concentrated around the zoo. Coral Gables also paid to erect its own boxes on the Granada golf course, not far from where the FIU researcher first discovered the bonneted bats. The city based its boxes on Ridgely’s design with one exception: It added tiny barrel tiles to its roof.
Whether the Patch of Heaven bat house repeats the success remains to be seen. It could not be better located: Bruce Matheson, whose father purchased the original 70-acre homestead in the 1960s, said the area was once pine rockland, the bat’s native habitat. A bat expert Hubbard contacted also confirmed the presence of bonneted bats near the bat house.
The garden is also near Castellow Hammock park preserve, one of the few remaining stands of the old hardwood hammock where Matheson said his father hunted wild orchids. Matheson lived in a cabin on the property constructed from the hardy Dade pine that covered the back half of the property. At the time, the family kept horses on the property, he said, and used it as a country getaway. Matheson lived in the cabin while he was a student commuting to Miami Dade College’s north campus for 7 a.m. classes.
Chesney has restored much of the hammock and buildings where they can be rented for weddings and other events — the old horse barn now serves as a chocolate bar. But the pinelands were razed to make way for a nursery after Costa Farms purchased the property.
While he’s less enthusiastic about the ornate gardens, Matheson is a fan of the bat efforts.
“I encourage them to do anything that will strike a balance with what nature used to be here in Dade County with what can still be retained,” he said.
In the coming weeks, FIU researchers plan to hang speakers to play bat calls to try to lure bats. Hubbard also has more elaborate plans for the grounds around the bat house, if he can stop workers from the neighboring nursery from herbiciding his fence line.
Behind and beside the house, he plans on planting trees to steer the bats west at sunset when they emerge, over Costa Nursery’s pot grow-houses. If the plan works, he imagines them mimicking the much-admired emergence of the UF bats, which swoop over Lake Alice not far from the campus’s weed science building, although a different kind of weed.
Eventually, once the garden’s nonprofit is up and running and better staffed, he hopes to open the garden to nightly watches that could create a Redland tradition as beloved as Gainesville’s evening flights.
“You gotta go see it,” Hubbard said one morning this month, still clearly delighted by the spectacle. “You sit there and it’s like good gracious, all those bats are coming out there? One bat can eat 1,200 mosquitoes in an hour. They are the best.”