The copper-tailed hummingbird (Eupherusa cupreicauda) is a fascinating and uniquely colorful hummingbird species endemic to only a few areas of extreme southern Arizona and southwestern New Mexico in the United States. This medium-sized hummingbird gets its name from the striking metallic reddish-copper color of the male’s tail feathers. The rest of the male’s plumage is primarily a bright iridescent green above and gray below. The female copper-tailed hummingbird lacks the coppery tail and is Instead more gray-green overall with a pale gray underside.
This endemic hummingbird’s extremely limited range and specific habitat preferences make it one of the most threatened bird species in North America. The copper-tailed hummingbird has been declining in recent decades and was petitioned for listing under the Endangered Species Act in 2014 due to threats from climate change, grazing, development, wildfires, and invasive species. However, the United States Fish and Wildlife Service found that listing was not warranted at that time. Still, the copper-tailed hummingbird remains highly vulnerable due to its restricted range and habitat requirements. Maintaining its limited habitat will be crucial for the survival of this uniquely North American hummingbird species.
Physical Description
The copper-tailed hummingbird is a medium-sized hummingbird, measuring 3.5-4.25 inches long with a wingspan of 4.3-4.7 inches and weighing around 3-5 grams. As mentioned above, the adult male has brilliant metallic reddish-copper tail feathers, an iridescent green back and crown, and gray underparts. The adult female lacks the coppery tail and is instead more uniformly grayish-green above with more uniformly pale gray underparts.
Both sexes have relatively short, straight dark bills adapted for feeding on nectar from flowers. Their tongues are specially adapted to lap up nectar, with forked tips allowing them to efficiently collect this high-energy food source. Copper-tailed hummingbirds have very high metabolisms and must feed frequently throughout the day from hundreds of flowers to power their beating wings which allow them to hover in place and fly swiftly forwards, backwards, and upside down.
Like all hummingbirds, the copper-tailed hummingbird has remarkably specialized flight abilities thanks to unique adaptations like rotating wrist bones that allow their wings to beat 55-75 times per second. This specialized anatomy also lets them take off instantly, fly midair backwards or upside down, and engage in elaborate courtship displays. The copper-tailed hummingbird’s wings make a distinctive metallic buzzing sound in flight. Despite their small size, these athletic birds are uniquely adapted for life on the wing.
Range and Habitat
The copper-tailed hummingbird is found only in the Madrean Sky Islands region of southeastern Arizona and southwestern New Mexico in the United States. This includes southern and eastern parts of Arizona’s Santa Cruz County as well as adjacent sections of southwestern New Mexico.
Within this limited range, the copper-tailed hummingbird inhabits streamside canyons and woodlands in higher elevation sky island mountain ranges between 4000-7000 feet in elevation. Their breeding habitat centers around major drainages including the Upper San Pedro River and Aravaipa Creek in Arizona. They are also found in similar streamside woodland habitat in isolated mountain ranges like the Huachuca, Santa Rita, Chiricahua, and Patagonia Mountains.
This endemic hummingbird depends on relatively lush streamside vegetation in semi-arid canyons, relying on the mix of flowering plants, tree cover, and running water sources these habitats provide. Within these scattered sky island canyons, the birds prefer areas with sycamores, oaks, willows, and other large trees that provide shade along with scrubby vegetation and natural flowering plants near seasonal creeks and streams. Unfortunately, this extremely localized habitat makes up only a tiny fraction of the American Southwest.
Diet and Feeding
Like all hummingbirds, the copper-tailed hummingbird primarily feeds on nectar from colorful, tubular flowers adapted to pollination by hummingbirds. Their slender bills and extendable tongues allow them to drink the nectar providing a high-energy food source. While feeding, they may also inadvertently pollinate the flowers. Favorite nectar sources include red flowers like penstemons, paintbrush, and coral honeysuckle, along with other regional flowers adapted to hummingbird pollination.
These hummingbirds have such fast metabolisms that they must visit hundreds of flowers each day. They feed every 10-15 minutes visiting a continual circuit of dozens of flowers. If not enough flowers are available, they may starve. The copper-tailed hummingbird’s specialized feeding behaviors are a co-evolved relationship with regional flowers. This coevolution demonstrates the interconnectedness and interdependence of plant and animal species.
In addition to nectar, copper-tailed hummingbirds will eat small insects for essential added protein. They may hawk flying insects in midair or glean them from vegetation. Preferred prey includes small bees, wasps, flies, spiders, aphids, and caterpillars. The birds use their slender bills to grab the tiny insects out of the air or vegetation in an acrobatic manner.
By balancing their diet between high-energy nectar and protein-rich insects, the copper-tailed hummingbird can survive in their harsh Southwestern habitat despite challenges finding food and water in the arid climate. Their unique adaptations allow them to exploit food sources unavailable to other larger desert species.
Life Cycle and Reproduction
The copper-tailed hummingbird breeding season aligns with availability of spring and summer flowers blooming in their montane habitat, generally from March to August. Females build tiny cup-shaped nests out of plant down, spider webs, and lichens on horizontal branches high in trees.
Males perform elaborate aerial courtship displays to attract mated pairs, flying in U-shaped or figure-eight patterns while singing a squeaky song ending in a sharp twitter. If a female is receptive, she will allow the displaying male to mate with her.
Females then lay two tiny white eggs about the size of a coffee bean in their delicate nests and incubate them for 14-19 days. The tiny chicks hatch blind and mostly featherless but develop quickly under the care of their mothers. They fledge from the nest in another 20-26 days, an exceptionally short nesting period compared to other birds. The rapid maturation allows the vulnerable young hummingbirds to escape risky nest sites faster.
The mother continues feeding the fledged young as they learn to fly and forage on their own. Within a couple months the young reach adult plumage and independence. Copper-tailed hummingbirds may raise two or even three broods per season. Their high reproductive rate is necessary to offset hazards the tiny birds face.
The copper-tailed hummingbird is solitary and territorial. Males establish breeding territories surrounding prime nectar sources to attract mates. They aggressively chase other males or even larger birds from their feeding areas. Nesting females may also chase away other hummingbirds. They defend an area around the nest tree from incursion.
Though solitary and territorial at nest sites, copper-tailed hummingbirds may congregate in optimal habitats when abundant flowers are available. Overall, these feisty hummingbirds exhibit specialized behaviors reflecting their tiny size and challenging breeding ecology.
Migration Patterns
Most copper-tailed hummingbirds migrate south to the state of Sonora in northwestern Mexico for the winter, likely because these lower elevations remain warmer and may provide more food resources. Banding programs show the birds leave southern Arizona in late August and September to migrate south across the Mexico border toward their wintering grounds.
They return again to southern Arizona as early as late February but primarily arrive in March and April as flowers begin blooming again in the Sky Island regions. Some birds may overwinter in southern Arizona if food resources allow. Overall the copper-tailed hummingbird exhibits a partial migration pattern, traveling relatively short distances compared to long-distance migrant species.
During migration they must cross significant barriers including the Sonoran and Chihuahuan Deserts. Like other hummingbirds, they fly alone usually at night and can lose up to half their body weight during migration as they burn through stored energy reserves. Given their already tiny size, long-distance migration is an exceptionally strenuous process. They also face hazards including predation, starvation, bad weather, communication towers, and more. Their survival depends on finding sufficient stopover habitats along their migratory routes.
Conservation Status and Threats
Unfortunately, the copper-tailed hummingbird’s severely restricted breeding range and habitat makes it highly vulnerable to extinction risk. Partners in Flight estimate there are only about 5000 breeding adults left. In 2014 this led to a petition for the copper-tailed hummingbird to be listed under the Endangered Species Act due to significant ongoing threats. However, the United States Fish and Wildlife Service found endangered status was not yet warranted since some breeding populations remain stable. The copper-tailed hummingbird is considered a Bird of Conservation Concern by the USFWS and remains extremely high risk.
Major threats include climate change, drought, development, grazing, habitat loss and degradation, invasive species, and wildfires. Rising regional temperatures and drying trends reduce flowering and nesting habitat. Groundwater pumping and human consumption deplete limited water sources these birds rely on in streamside habitats. Development for homes, roads, and ranching infrastructure damages their specialized habitat.
Overgrazing by cattle degrades vegetation and soils along riparian areas. Invasive species like tamarisk outcompete native vegetation. Catastrophic wildfires incinerate critical habitat faster than the ecosystem can recover in the hotter, drier conditions. Loss of migratory stopover habitat in Mexico also threatens their survival. Intensive threats across their range make successful conservation action urgent.
Conservation Solutions
To protect the beautiful copper-tailed hummingbird, several forms of conservation action are urgently needed:
– Habitat protection – Conservation easements, land acquisition, and habitat restoration projects focused in key strongholds like the Upper San Pedro River and Chiricahua Mountains.
– Riparian restoration – Replanting native vegetation and enhancing habitat along riparian zones. Removal of excessive groundwater pumping and livestock overgrazing.
– Wildfire management – Strategic fuel reduction and ecological burning to restore natural fire regimes and enhance ecosystem resilience against megafires.
– Development controls – Limiting new homes and infrastructure near sensitive habitats. Stronger environmental regulations.
– International cooperation – Habitat conservation across the US-Mexico border along migration routes and in winter range.
– Invasive species control – Removal and management of tamarisk and other habitat-altering invaders.
– Climate change mitigation – Broader efforts to control emissions and limit impacts of accelerating climate shifts which amplify other threats.
– Continued monitoring – Tracking population trends and habitat quality over time to target conservation actions.
By taking intensive management actions guided by research, government agencies, conservation groups, and local partners can ensure the unique copper-tailed hummingbird continues brightness Southwestern canyons with its metallic buzzing and brilliant plumage far into the future. This endemic species is a keystone of these arid region ecosystems.
Conclusion
The copper-tailed hummingbird is an incredibly unique and thrilling bird species. Its metallic plumage and dramatic canyon habitat make it a treasure of the Southwestern United States. However, this endemic bird needs urgent support to maintain its limited breeding and migratory habitats in the face of intensive ongoing threats. Targeted conservation efforts focused on enhancing habitat quality, controlling invasive species, improving wildfire regimes, limiting climate change, and restoring hydrological processes can help ensure the copper-tailed hummingbird remains a vibrant part of the ecology of the Sky Island region. With intensive management guided by science, this diminutive species can continue charming its way into the hearts of bird lovers and inspiring awe at its toughness and resilience against challenging odds. The copper-tailed hummingbird is a threatened gem representing the distinctive biodiversity of the American Southwest.