Arizonans Are Helping a Desert Warbler Expand Its Housing Options
A DIY nest box program run by Tucson 探花精选 provides new living quarters for Lucy's Warblers. The key, though, is to land the perfect shape.
The echo through the Tanque Verde Wash in Tucson鈥檚 east side. It鈥檚 mid-April, and the birds have just migrated from Northern Mexico to breed and raise their families in the dripping Arizona canyonlands. This morning, there are at least two of the small, gray-plumed males singing and flying from branch to branch on the cottonwood trees. Their partners are nearby as well, maybe tucked inside the nest boxes recently installed by the .
Olya Phillips, the chapter鈥檚 citizen science coordinator, is here to document the number of nesting Lucy鈥檚 and keep track of the eggs they鈥檝e laid. The team鈥檚 research on the birds has been ongoing for five years, focusing on how human-made habitat might benefit the local population. In the past, Lucy鈥檚 Warblers were largely ignored, Phillips says, largely because they were thought to be a desert-only species. But when Tucson 探花精选 heard stories of them popping up in peoples鈥 yards, the staff decided to launch the first-ever nest box program for the bird.
Since 2014, Tucson 探花精选 has enlisted dozens of elementary school kids and other volunteers every spring to build and install the contraptions around Arizona. The aim isn鈥檛 to reverse decline, but rather to prop up the birds long before they land in crisis. Part of that includes rolling survey data into a larger conservation strategy for the warblers. 鈥淲e鈥檙e in the heart of their breeding range. There should be a plan so that we can help them in the future,鈥 Phillips says.
Lucy鈥檚 are one of just two U.S. warbler species that lay their eggs in cavities (the other is the eastern Prothonotary). They typically hole up in mature mesquite trees across the Sonoran Desert. But as the region鈥檚 water table declines, the trees are dying. What鈥檚 more, wood harvesters cut mesquite down, and because young trees encroach on grasslands and other grazing areas, so does the state.鈥淭he one thing that Lucy鈥檚 need is being aggressively fought in many areas,鈥 says Jonathan Horst, Tucson 探花精选鈥檚 conservation and research director.
Fewer nesting trees might mean fewer warblers in the future. To keep the local population from slumping, Horst and Tucson 探花精选 did something that no one else had succeeded at: They devised a nest box that would bring the picky species to urban yards or conservation areas like the Tanque Verde Wash.
The process involved a lot of trial and error, Phillips says. In the first year, the team mimicked classic nest-box blueprints, but none of the rectangular residences attracted Lucy鈥檚 Warblers. They then used measurements from natural cavities to land on with an entrance on each side, allowing for better ventilation in scorching summer conditions. The new design made all the difference.
Last year volunteers set up 1,400 boxes across half the length of the state, from as far north as the Tonto National Monument to as far south as Nogales. After testing the triangular layout against four other shapes, the team discovered that the occupancy rate hit 75 pecent. They also counted close to 200 Lucy鈥檚 fledglings from all the boxes.
Perhaps some of the most enthusiastic builders are the fourth-grade students of Manzo Elementary School, located in Tucson鈥檚 historic Barrio Hollywood neighborhood. On a sunny afternoon, six of them sit around a picnic table, attentively listening to Phillips and Horst鈥檚 directions on how to assemble the boxes and gleaning fun facts about the warblers.
鈥淭he more opportunities we can give kids to be exposed to nature and understand natural processes鈥in this case bird nesting鈥the better the overall education is,鈥 says Blue Baldwin, an educator at Manzo. 鈥淚f we want students who care about the Earth and the environment, they need to understand both.鈥
For Horst, it鈥檚 especially important to reach out to kids to establish a community that can support long-term stewardship efforts. He remembers the impression the Eastern Bluebird boxes on his grandparents鈥 farm in Virginia had on him growing up. Though his family didn鈥檛 know it at the time, the foot-tall nesting condos, hosted in yards throughout the species鈥 range, would propel its comeback in the 1970s and 鈥80s. That, to Horst, was proof that conservation starts at home. Someday for a new generation of Arizonans, Lucy鈥檚 Warblers might set the same example.
Correction: Arizonian was updated to Arizonan, the more accepted term, throughout the story.
This story originally ran in the Summer 2019 issue as 鈥淲e Love Lucy鈥檚 Warbler鈥s.鈥 To receive our print magazine, become a member by .