Fledglings take flight: Good news for the nation’s most endangered bird

by Anders Gyllenhaal
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The wildlife managers who bred more than 200 Florida Grasshopper Sparrows in a laboratory setting over the past two years knew they faced a tricky question when it came to releasing the birds into the wild this spring:

A Florida Grasshopper Sparrow about to be released

Would they know how to act like grasshopper sparrows?

Could they sing the sparrow’s unique courting song? Would they know how to hide from hawks? Would they have the instincts to build nests, mate with wild sparrows and raise their young together?

The captive-breeding experiment is the culmination of a decades-long project to revive the most endangered species in the U.S.. Only 30 pairs of the sparrows remained in the wild when the team decided they had no choice but to try producing chicks in captivity, then introducing them back into the wild in hopes they’d multiply.

The answers to all their questions came pouring in over the course of the breeding season that is now coming to a close.

A bundle of newborn sparrows in a hidden nest in the grasslands. Photo by Amanda Adams.

The birds not only mastered the routines of the mating season, they gave birth to a new generation of Florida Grasshopper Sparrows over the summer. ( Forty-two birds were born from captive-bred birds and altogether 64 were born from wild and captive-bred birds.) Almost all have now left the nest and flown off to begin life on their own.

“We’re very happy with what we saw this first season,’’ said Juan Oteyza, the research biologist with the Florida Fish and Wildlife Institute that oversees the project. “It seems to be paying off.’’

Craig Faulhaber, avian conservation coordinator for the state Fish and Wildlife Conservation Commission, said it was hard to tell the captive-bred from the wild sparrows. “They showed all the normal behaviors,” he said. “They bred successfully. They took care of their young. They acted just like wild sparrows.”

Flying Lesson: The project to save the Florida Grasshopper Sparrow has been full of discoveries for researchers. They’ve learned what it takes to breed birds in captivity, protect fragile nests from harm and how to begin to replenished the depleted population. It’s not yet clear if the project will be successful, but already the lessons are proving valuable to help understand the woes of the grassland birds like the sparrow.

Sarah Biesemier (left) and Juan Oteyza, state biologists who oversee the project, arrive at the prairie with a carrying case full of sparrows.

The grasslands 50 miles south of Orlando where the last of the grasshopper sparrows have congregated is one of the most studied patches of bird habitat in the country.

State and federal managers, nonprofit supporters and some of the nation’s leading bird researchers spent hours walking the fields and peering through binoculars at the sparrows on their daily rounds. Every sparrow is known, identified by a combination of colored bands on its legs.

We’ve been following this story for more than a year, as it is one of the innovations scientists are trying in order to save fragile species. Here’s an in-depth package that ran in the Washington Post in May, and here’s a Flying Lessons post on the long term outlook for species like this.  

A Florid Grasshopper Sparrow sings from its perch on the Florida Prairie. Photo by Sara Beisemier.

The rescue mission is important for a litany of reasons.

The Florida Grasshopper Sparrow is the flagship bird of the unique grasslands called the Florida Prairie, 90 percent of which ha disappeared territory as the state has grown. And while the prairie environment is distinct, the troubles with grassland birds are not; no other segment of birds has faced declines that grassland species have across the country.  What researchers learn from the grasshopper sparrows can help other birds. 

A fledgling grasshopper sparrow, looking more like a beak on a tangle of feathers than a bird, makes its way near the nest. Photo by Amanda Adams.

The encouraging report from the breeding season is some of the first good news for the grasshopper sparrow since its sudden and mysterious decline that began nearly two decades ago. Despite the progress on the sparrow population, researchers still don’t know what is causing the near evaporation of the subspecies. 

Reed Bowman, director of Archbold Biological Station’s Avian Ecology Program who has worked on the project since its inception, said the arrival of so many captive-bred birds could help researchers decipher the cause of the declines. Wild birds have continued to decline right up until this breeding season; if the captive population proves to be healthier, that would indicate a biological cause of the decline, such as inbreeding, as opposed to an environmental one.

“Honestly, that would be great news if (captive-bred birds) declined at a lower rate than wild birds,” he said. “We will get some insights.”

A grasshopper sparrow steps warily out of its carrying case.

The breeding results are a reminder of how challenging this rescue mission will be.

Most of the released birds did not survive, which is normal for birds like these. Others didn’t end up breeding the first year out, although they may in later years. So while the total population of grasshopper sparrows on these grasslands about doubled, the total number of breeding pairs — the key calculation for expanding the population — remained about the same for the sparrows at the several site in the area where they’re found. 

The North Florida enclosure where most of the captive-bred birds are raised.

Still, the species is making progress, which in turn is encouraging to the consortium of state and federal agencies, conservation organizations, non-profits and foundations that help fund the project that costs about $1.2 million a year. “This has been a huge positive,” said Bowman. Andrew Walker, president of the Fish and Wildlife Foundation of Florida, a nonprofit organization that helps raise funds for the project, added: “We’re committed to this for the long haul.”

Understanding the inner workings of birds

The sparrow mission comes at a time of expanding knowledge of the inner workings of birds. The breeding success this year suggests that birds develop from a combination of genetic programming and training from parents and peers.

 If you’re interested in learning more about these intricacies of bird life, two exquisite new books are out that explore elements of the topic. One is Jennifer Ackerman’sThe Bird Way: A New Look at how Birds Talk, Work, Play, Parent and Think. Her new book follows up on The Genius of Birds, which made the case for how smart birds are. You can find an excerpt of her new book at the Audubon site here.
 
The second book is Becoming Wild: How Animal Cultures Raise Families, Create Beauty and Achieve Peace, by science writer Carl Safina. The book tells the story through sperm whales, chimpanzees and macaws. While the whole book is fascinating, the middle chapters on macaws are must reads if you interested in what makes birds tick.
 

A male grasshopper sparrow about to be released. About 50 more captive-bred birds will be released in the coming months to continue to bolster the population. Photo by Anders Gyllenhaal.

 
 
 
 

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lizagyllenhaal September 12, 2020 - 6:41 pm

How great that this story has a happy ending — or promising beginning! Thanks for this in-depth look at this tiny bird and the big effort being made on its behalf. It gives one hope!

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