Sanibel researcher seeks answers to questions about rare bird
In a world of hyper-examination, it’s hard to imagine wildlife that biologists know little about.
But in Sanibel’s own back yard lives the Mangrove Cuckoo, an elusive bird about the size of a bluejay that nestles deep in south Florida’s mangrove forests. The bird’s froggy vocals and distinct features thrill birders and biologists snatching the occasional glimpse of its bandit-masked face and long tail feathers.
Because it’s difficult to observe and because the population is diminished, the Mangrove Cuckoo has acquired a fabled status, said Rachel Mullin, a wildlife biologist documenting the bird in Sanibel, helping in a habitat plan to ensure its survivability.
Mullin is assigned to the J.N. “Ding” Darling National Wildlife Refuge, where it’s estimated some 30 Mangrove Cuckoo birds make home, or at least use as a stopover. One cuckoo Mullin tracks by radio has ventured from Sanibel into Estero Bay, ending up in Charlotte County and back to Bokeelia in Pine Island a few days later. The stationary bird requires no less than 65 acres to survive. The average bluejay, on the other hand, uses about five acres to nest and socialize, Mullin said.
Mullin works with Ecostudies Institute, a west coast research and wildlife advocacy group started in 2001. She has worked at the Darling Refuge tracking the cuckoo since 2012. Her contract with the US Fish & Wildlife Service ends next spring. US Fish & Wildlife oversees the refuge established in 1945. There are some 230 species of birds in the 6,500-acre refuge. Mullin is recognized as a top expert in the field, asked to speak at science conferences and birder workshops. She will co-author a final report in 2015.
An obvious oddity to her work is the bird’s name, she said. Ding Darling regulars have good-naturedly called Mullin the cuckoo lady, she said, traveling the preserve in her Toyota truck armed with a tracking antenna.
“At first I was like ‘whoa, whoa,'” said Mullin, 32, a California native. “And then it was funny.”
Ecostudies and other naturalist groups have tracked the three species of cuckoo in south Florida for about 15 years. Mullin said there has been a nearly 90 percent drop in the number of birds tracked in the last couple of years, “obviously causing concern,” she said. Development, pollution and other causes are listed as threats. Birds have been studied in federal wildlife preserves looping south and along the Everglades. Her study in the Ding refuge will include habitat and other recommendations to help the cuckoo flourish into the next decades, she said.
But for the immediate future, Mullin will continue to arise before the sun, shroud herself in a bug-proof body suit, climb into a kayak, and begin her search for the Mangrove Cuckoo in its mosquito/no-see-um-infested preserve. Occasionally she will hear the bird bleat in its throaty caw that sounds like frogs with laryngitis. She has observed cuckoos dine on frogs and other critters. Their nests are primitive, mostly impenetrable. Male and female cuckoos look the same.
Once a cuckoo has been centralized, Mullin will radio Ding volunteers assisting in a trapping. The group assembles a structure like the foul-ball netting behind a batter’s box; tall as the mangrove trees and several yards wide. Mullin lures the birds from their mangrove sanctuary with an IPhone held to a speaker. The sound is another cuckoo calling. Occasionally one of the birds will launch into the netting. The ensnared birds are particularly feisty, she said. She fits a leg band and a fanny-pack transmitter on the bird’s body that allows her to track it for 115 days. She spends hours in a small plane tracking the birds’ flight. The information is vital in building a portfolio of recommendations that ultimately get presented to the US Fish & Wildlife experts overseeing Darling and other federal preserves, she said. This year Mullin has affixed 13 of the $100 transmitters on cuckoo birds. She got just six in 2012.
Mullin’s work is about the down and dirty; crawling through mangrove, boating backwaters in search of her elusive target. One such episode caused the shredding of protective clothing, a heavy dappling of mud. She happened to emerge from the undergrowth as a tour bus of Ding visitors passed.
“I was a disaster,” she said. “I thought to myself, ‘you’re a very gross person.’ It was awfuland funny.”
A side note to her work involves hobbyists. An English birder studying her research on the web journeyed to Sanibel to trundle along on a scouting mission. The man ended the day bear hugging Mullin, so pleased that she had given the opportunity to observe the rare bird.
“(You) work so hard to find them,” she said of the netting effort. “Your heart stops” holding one. “It’s a great achievementbecause you’re going to get results.”
Track Mullin and other Florida research at the Ecostudies Institute Facebook page, or at ecoinst.org.