RUFOUS HUMMINGBIRD (Selasphorus rufus)
When seen well, an adult male of this species is the easiest of the Montana hummingbirds to identify, with a flaming orange-red gorget and a rufous back and tail. In flight, it can be mistaken for a Broad-tailed Hummingbird if the observer is not aware that males of each species produce a distinctive wing trill. Rufous Hummingbirds of both sexes are belligerent bullies at feeders and flower patches, routinely driving off conspecifics, Calliopes, and Black-chins and even chasing larger species such as Anna’s and Broad-tails. The Rufous has the northernmost range of any hummingbird, breeding from 61°N in se. Alaska and s. Yukon south through British Columbia and extreme w. Alberta to s. Oregon, s. Idaho, sw. Montana, and perhaps nw. Wyoming. It winters primarily in Mexico but has become regular in the se. U.S. from Texas to Virginia, where it is the most likely western hummingbird to be seen in winter. A true wanderer, it is the only hummingbird that has been found in every state on the North American continent.
Status and Occurrence: Fairly common breeding resident in the western third of the state east to the Helena Valley. Migrants are well documented as far east as the Pryor Mts. Arrival occurs from late Apr to mid-May and departure from Jul through Aug. The earliest sighting was by Cynthia Hudson at Alberton on 20 Apr 2010, and the latest record was a juvenile male banded by Ned and Gigi Batchelder in the Bitterroot Valley on 6 Oct 2009 (the only Oct record for the state). Like many species of hummers, males precede females in spring and leave before them in summer. Peak movement of southbound adult females and juveniles occurs from late Jul to early Aug (N. and G. Batchelder, pers. comm.). Nesting occurs from mid-May through Jul, later nests sometimes being second attempts by multibrooded females (see below). At Fortine from 1920 to 1973, Weydemeyer (1975) found nests with eggs between 3 and 25 Jun and the earliest hatchlings on 10 Jun; the latter birds would have fledged in late Jun. At various locales from 2004 to 2010, Ned and Gigi Batchelder captured females with oviducal eggs between 5 May and 30 Jun.
Four Rufous Hummingbirds collected near Waterton Lake by Elliott Coues on 19 and 20 Aug 1874 were the state’s first specimens; one is extant (USNM 67651). R. S. Williams took single birds at Columbia Falls on 9 Aug 1894, 31 May and 25 Jul 1895, and 27 May 1896 (MCZ 188342-188345), and A. H. Howell obtained one at Nyack on 22 Jun 1895 (USNM 140335).
Habitat: In Montana, Rufous Hummingbirds commonly occur in early successional habitats following timber harvest but also use riparian shrubs, mixed conifers, openings in mature forests, and postfire habitats (Calder 1993, Hutto and Young 1999). They attend feeders in residential areas adjacent to coniferous forests, especially during migration and after the breeding season. The nest is made of plant down, moss, and spider silk and is covered with lichens and placed in a well-concealed location in a tree or shrub within 5 m of the ground. Like other hummingbirds in Montana, the Rufous feeds mostly on floral nectar and flying insects and also feeds on sap and trapped insects at sap wells made by Red-naped Sapsuckers.
Conservation: Level III Priority and Potential Species of Concern in Montana because numbers are declining in much of its range outside the state, and little is known about productivity and population trends in the state (Casey 2000). BBS data for Montana suggest that numbers increased significantly by 5% per year from 1966-2009, which was the only significant increase among the states and provinces that recorded the species on BBS routes. Owing to low abundance, however, the data had poor credibility. During the same period, numbers decreased significantly by 2.3% per year survey-wide. If these perceived declines are real, the reasons for them are unknown (Calder 1993). Also unknown is whether nesting success in habitats created by timber harvest is similar to that in naturally occurring early successional habitats (Hutto and Young 1999). The global population estimate is 6.5 million birds (Rich et al. 2004).
Historical Notes: Elliott Coues apparently was the first naturalist to see a Rufous Hummingbird in Montana, collecting four of them in Aug 1874 and noting that it was “Found in considerable numbers at our camp on Chief Mountain [= Waterton] Lake, in open flowery spots amongst the windfalls, at an altitude of about 4,200 feet” (1878: 614). McChesney provisionally identified the hummingbirds he saw along the Bighorn R. in 1878 as Rufous on the belief that it was “the sole boreal representative of the family, so far as is now known” (1879: 2390). Bendire noted only that “Mr. R. S. Williams writes me from Columbia Falls, Montana, that he has found the Rufous Hummer in the valley of the upper Missouri River” (1895: 214); the correspondence probably was posted before Williams had first collected the species at Columbia Falls in the summer of 1894.
In the summer of 1900, Silloway (1901a) collected specimens near Bigfork and at McDonald Lake, but their whereabouts are unknown. Later in the 20th century, Saunders (1914b) found the species along the foothills of the Rocky Mountain Front, and DuBois (1938) provided a lengthy description of the events at a nest he observed near West Glacier in 1914.
Contemporary Work: Elinor Jones reported on color variation in Rufous Hummingbirds in the Swan Valley from the late 1980s to the early 1990s. Back color of adult males ranged from totally rufous to a mix of rufous and iridescent green feathers, and individuals that had green back feathers tended to have more rufous ones when caught in subsequent years (Jones 1992a). Almost all males banded as juveniles had fewer green back feathers when recaptured in their second year. Adult females had unique throat patterns consisting of rows of bronze-green flecks laterally and varying numbers and configurations of iridescent red feathers centrally (Jones 1993). The amount of red feathering increased with age, with females adding an average of 1.4 feathers on their throats per year.
At Flathead Lake Biological Station at Yellow Bay in 1995, Charles and Leann Blem examined how sucrose concentration and feeder height affected food intake by Rufous Hummingbirds (Blem et al. 1997). In the first experiment, sucrose concentrations in test vials were 20, 30, and 40%; 30, 40, and 50%; 40, 50, and 60%; and 50, 60, and 70%; vials were presented at heights of 1.25, 1.63, and 2.0 m above ground. In the second experiment, vials filled with 40% sucrose solution were presented at 25-cm intervals from 25 cm to 3 m above ground. In all but trials with the highest concentrations (50-70%), birds preferred vials with the highest sucrose content and those that were placed the highest above ground such that the most-preferred vials were those with the highest sucrose at the highest points. In the second trail, birds consistently consumed the most solution from the highest vials. Thus, sugar concentration was important when solutions contained 60% sucrose or less. When sucrose concentrations were 50% or more, birds showed no preference for concentration but still preferred to feed highest off the ground. Hummingbirds probably avoided feeding close to the ground to reduce the risk of mammalian predation.
In follow-up experiments in 1996 and 1997, the Blems examined the precision with which Rufous Hummingbirds selected among solutions of different sucrose concentration (Blem et al. 2000). When presented with feeders that varied in concentration from 10 to 70% (in increments of 10%), the birds preferred 50% sucrose to higher or lower concentrations. At sucrose concentrations that approximated those in flowers pollinated by hummingbirds (20%), birds could distinguish solutions that differed by only 1% sucrose content. At concentrations above and below 20%, a greater difference between choices was needed for the birds to show significant preferences for sucrose content. The results suggested that Rufous Hummingbirds can discriminate among subtle differences in sucrose concentration when obtaining nectar in the wild.
On 27 Jun 2008, Dale Livezey found a Rufous Hummingbird nest with two eggs about 1 m off the ground in a small Douglas fir along Placid Lake. Later that day he watched the female fly to a second nest about 6 m off the ground in a taller Douglas fir 20 m from the first nest. The second nest contained one large nestling that was within a week of fledging. On 2 Jul, Livezey, Bob Martinka, and Ned Batchelder watched and photographed the female feed the nestling at the high nest and incubate the eggs at the low nest, thus documenting the first case of simultaneous double brooding known for the species (Batchelder et al. 2012). The young from the low nest fledged in early Aug.
Banded Birds: As of 1 Jan 2012, more than 20 Rufous Hummingbirds banded in Montana had been re-encountered in a later year or at a different location than the banding site. A hatching-year female banded near Swan Lake by Elinor Jones on 25 Jul 1988 was caught at Gothic, Colorado, by William Calder on 9 Aug of that year, 1,200 km southeast of the banding site. Calder and Jones (1989) believed that the bird could have covered the distance in one flight, especially if tailwinds had been available. Other significant re-encounters include a hatching-year female banded near Conner by the Batchelders on 10 Aug 2007 and found dead near Cordova, Alaska, on 15 May 2009, and an adult female banded near Hamilton by the Batchelders on 21 May 2010 and recaptured in sw. Texas on 8 Aug 2010, about 2,000 km away.
The Batchelders captured four Rufous Hummingbirds in Montana that had been banded elsewhere. The most amazing of these was a hatching-year female that had been banded in Virginia, well outside the species’ normal range, on 29 Nov 2001 and recaptured near Red Lodge on 1 Aug 2002. The bird was again captured in the same yard in Virginia on 1 Dec 2002, suggesting that Virginia was its regular wintering area. The Batchelders also caught an adult female near Bigfork on 15 May 2004 that had been banded in Arizona on 25 Aug 2002, and another adult female near Victor on 18 Jul 2007 that had been banded in Colorado on 12 Aug 2006. Their last recapture of a foreign bird was at Hamilton on 25 Jul 2007 of an adult female that had been banded on Vancouver I., British Columbia, two months earlier.
Sponsored by Margaret Petty, Stevensville
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