The diversity of hummingbird species in SABO’s ongoing monitoring project on the San Pedro River now goes to eleven! A juvenile female Magnificent Hummingbird, banded last Thursday at Casa de San Pedro B&B, is the latest addition to our study. She’s a giant compared to our usual clientele: bill length 27.3 mm, wing length 67.2 mm, tail length 40 mm, weight 7.3 grams.
Magnificent Hummingbirds are residents of pine-oak forest from central and northern Arizona south into Central America. Though uncommon to fairly common just a few miles away in the Huachuca Mountains, “Mags” are rare spring and fall visitors to the cottonwood-willow habitats of the San Pedro River. One of our regular banding session visitors had the honor of assisting in the release of this young ambassador from the “sky islands.”
In honor of this new species for the study, we tallied the numbers of each hummingbird species banded so far at our two sites on the San Pedro River (San Pedro House August 1995-present and Casa de San Pedro B&B 2011-present, hybrids not included):
|* breeds on the San Pedro River|
Only six banding sessions are left in the 2016 season (three at each of our two sites), and there may be few or no birds still around for the last two sessions, so make plans to join us this weekend or next weekend. See SABO’s Calendar of Events for more information.
Thanks as always to our dedicated volunteers, our hosts Karl and Patrick at Casa de San Pedro and the Friends of the San Pedro River, and SABO’s many members and donors, all of whom make possible the continuation of this landmark study.
It’s been a very busy spring at SABO’s hummingbird banding stations! Our team has been seeing lots of recaptures from previous seasons (including one at least 8 years old!), many females with developing eggs, and various colors of pollen reflecting a good season for natural nectar, but also one bird that’s seen some hard times. Check out the photos below for highlights!
A very rare “pastel” Sandhill Crane is spending the winter at the Arizona Game and Fish Department’s Whitewater Draw Wildlife Area. This handsome mutant was spotted by SABO Director/Naturalist Tom Wood on January 31 during the flock’s midday fly-in and photographed by SABO member Michelle Cook.
Pigment abnormalities of any kind are seldom observed in Sandhill Cranes, affecting fewer than one in 200,000 individuals. This bird, which we’re calling “Pearl,” sports very pale plumage, a condition known as dilution. Both eumelanin, the pigment responsible for blacks, grays, and dull browns, and the red-brown pigment pheomelanin are present but at greatly reduced concentrations, a form of dilution called “pastel.” “Pearl’s” bill and legs are also paler than those of a normal crane, which is typical for dilute birds. On its forehead, some pale orange skin shows through pale beige juvenile feathers. The red skin color of adults is created by carotenoid pigments unaffected by dilution mutations, so “Pearl” should have a normal-looking red forehead if it survives to adulthood.
An odd-colored adult Sandhill Crane that spent the winter of 2003-2004 at Whitewater Draw Wildlife Area, dubbed “Moby” by SABO staff, had mostly white plumage with scattered normal and gray-shaded feathers and normally pigmented eyes, bill, legs, and forehead. A pattern like this is consistent with a common but mysterious condition called “progressive graying.” Affected birds appear normal in their early years of life but acquire white feathers with age, sometimes becoming mostly or entirely white. Extreme cases may ultimately affect the skin, bill, and legs as well. This condition may be related to the human pigment disorder vitiligo or simply represent an avian version of gray hairs.
With rare exceptions, progressive graying is nearly indistinguishable from leucism* (pronounced with a hard “c”), a relatively rare condition characterized by pure white feathers either in patches among normal ones or over the entire body. Affected birds with no normal feathers (total leucism) usually have unpigmented skin, bills, and legs and are distinguished from true albinos only by their normally colored eyes. Partially leucistic birds have patches of pure white feathers among normal ones, often in nearly symmetrical patterns, and skin that may be normal or patchily pigmented. Albinism is an extreme condition in which affected animals produce no melanin pigment at all; though you often see the term used informally, there is really no such thing as “partial” albinism.
The reduced melanin may make “Pearl” more vulnerable to sunburn and feather wear as well as more conspicuous to predators. Nevertheless, we have high hopes that this remarkable bird will survive to winter with us again.
For more on pigment abnormalities in birds, see:
Many thanks to Michelle Cook for documenting this rarity and allowing us to use her photo to illustrate this post! If you are lucky enough to see and photograph “Pearl” and would be willing to allow SABO to use your photos in our education and outreach programs, please contact us.
* “Leucism” has a long history of misuse as a catch-all term for any reduction in pigment.
If you can’t join SABO this winter for a Whitewater Wetlands Walk and/or Sandhill Crane Watch, the Arizona Game and Fish Department has provided the next best thing: a live video feed from the playa lake at Whitewater Draw Wildlife Area!
The feed is best viewed between 6:30 to 8:00 a.m. when Arizona’s largest flock of Sandhill Cranes departs for breakfast in nearby farm fields, between 11:00 a.m. and 2:00 p.m. when the majority of the flock returns, and between 4:00 and 6:00 p.m. when the last stragglers return to the roost for the night. Even when the cranes are not present, you may see some of the ducks, shorebirds, songbirds, and birds of prey that make their winter home at the wildlife area.
Thanks to our colleagues at Arizona Game and Fish for sharing our cranes with birders and wildlife watchers the world over!
(The video above is from SABO’s YouTube channel.)
The Sandhill Cranes are back at Whitewater Draw Wildlife Area and SABO’s winter activities are on the calendar. We’ve fixed a glitch on the website to now allow online registration for our Sunday morning walks at Whitewater followed by crane watching from the viewing platform. Come join us for one of the area’s best wildlife viewing opportunities.
Though it’s the hummingbird most familiar to most Americans, the Ruby-throated is the third rarest of Arizona’s 18 recorded hummingbird species. Despite generations of intense observation by some of America’s most experienced birders and ornithologists, it wasn’t until January 2005 that a possible female Ruby-throated was discovered wintering in the Tucson yard of a professional birding guide. At the request of the host, this bird was banded by SABO Director Sheri Williamson and confirmed by measurements and plumage characteristics as Arizona’s first known Ruby-throated and 18th hummingbird species.
Sightings of an adult male at the Paton feeders in Patagonia in September-October 2007 and September-October 2008 almost certainly represent a single bird. It was a long wait for the fourth record/third individual, another adult male in late September 2015 at the home of another birding guide in the northern Chiricahua Mountains.
Though SABO’s hummingbird banding team is always alert for the possibility of a migrating Ruby-throated among the hundreds of Black-chinneds at our banding stations along the San Pedro River, Arizona’s fifth record/fourth individual, a juvenile male, turned up after the end of this year’s banding season in the Bisbee yard of SABO Directors Tom Wood and Sheri Williamson. This handsome and fierce little bird is now the second member of its species to be banded in Arizona.
It seems likely that Arizona’s scant handful of Ruby-throated Hummingbirds came from the western part of the species range in southern Alberta and extreme eastern British Columbia, but we’re hoping that this newly banded individual will be re-encountered someday somewhere, shedding a bit more light on this familiar yet mysterious bird.
SABO’s ongoing hummingbird research is supported by the generosity of our members and donors. If you’d like to help, we hope you’ll consider making a tax-deductible donation or “adopting” a banded hummingbird for yourself, a family member, friend, or colleague.
Tomorrow (Saturday, October 3) at the San Pedro House will be our final hummingbird banding session for 2015 and the end of SABO’s 20th season of monitoring hummingbirds on the San Pedro River.
The celebration will start at 3 p.m. with a short presentation by SABO Director Tom Wood on what we’ve learned so far, followed by banding from 3:30 to 5:30 and recognition of our volunteers (with cake!) from 5:30 to 6 p.m.
No reservations are required and there is no fee to attend, but donations to help SABO continue the project are gratefully accepted. The San Pedro House is on the San Pedro Riparian National Conservation Area, approximately 7 miles east of Sierra Vista on S.R. 90. The entrance is on the south side of the highway and the west side of the river.
With this week’s surge in migration, we’re rapidly approaching a major milestone in SABO’s 20-year study of the hummingbirds of the San Pedro River: 6000 hummingbirds banded at our main banding station at the San Pedro House.
We expect to reach this milestone at our next banding session, so we invite you to join us at the San Pedro House next Sunday, September 6, from 4 to 6 p.m. to help us celebrate and learn more about what these amazing birds have taught us. You might be the lucky visitor who gets to launch (and/or adopt) #6K!
Migration is finally in full swing! This week’s banding session at Casa De San Pedro B & B was by far the most exciting of the fall migration, with 20 new birds of six species. Highlights included three impossibly tiny Calliopes (a stunning adult male and two juveniles), adult male and juvenile male Broad-tailed, and two adult Black-chinned with “gray hairs,” giving the adult female the appearance of having some junco in her family tree. (Click the photos below to see a larger version.)
Our banding team was fortunate to be able to share the diversity and majesty of these “little big birds” with the B&B’s guests and a few visitors.
Banding session continue through the first weekend in October. The public is always welcome at banding sessions at the San Pedro House; reservations may be required for sessions at Casa de San Pedro. “Adoptions” of banded birds will be available for a $25 contribution to SABO.
SABO’s hummingbird banding team has been busy on the San Pedro River! Over the last four banding sessions (two at each site), we’ve caught 32 “new” (unbanded) birds (25 Black-chinneds, 7 Broad-billeds) and recaptured 8 previously banded birds (all Black-chinneds). Captures at Casa de San Pedro Bed & Breakfast (27) have been running significantly ahead of those at our original site at the San Pedro House (13), and young birds (27) greatly outnumber adults (13).
One recent recapture at the San Pedro House is E64396, named “Anna” by her sponsors. She was banded as an adult in April 2008; at a minimum age of 8 years, she’s among the oldest individuals in our study. This was her seventh recapture in total and her fourth this year! Her abdomen was swollen indicating a developing egg; if the nest is successful, the young should fledge in late August.
Another important recapture at the San Pedro House was P44518, a female Black-chinned banded by our team 27 months earlier and almost 10 miles farther south at Casa de San Pedro. She had an egg in development at the time of her original capture but no sign of breeding on her recapture. Since this was her first recapture, it’s hard to say whether she is now part of the population near the San Pedro House or just a post-breeding visitor.
A celebration marking the 20th year of the San Pedro Hummingbird Project is tentatively scheduled for Saturday,
September 26 October 3. Stay tuned for details! We’re also counting down to our 6000th hummingbird banded at the San Pedro House. With just 48 new birds to go, we expect to reach 6K before the end of the season.
There are only 18 sessions left in the 2015 banding season, 9 at each site. If you’d like to join us, please check the Calendar of Events for upcoming dates. If you’d like to help us keep the project going, please consider making a donation or “adopting” a banded hummingbird for yourself or as a gift. Thank you for your support!