RUby-throated HUMMINGBIRD (Archilochus colubris)
This species is the only hummingbird that breeds east of the Great Plains and thus is the only one that many residents of the e. U.S. will ever see. Adult males have a ruby throat, black chin strap, and metallic green back and are unlikely to be confused with other species. Adult females and juveniles, however, closely resemble a female Black-chinned Hummingbird and are best told from that species by their slightly shorter bills and pointed outer primaries. Ruby-throated Hummingbirds are well known for migrating across the Gulf of Mexico, the birds taking on fat stores of nearly half their body mass to prepare for the long nonstop flight (Norris et al. 1957, Odum et al. 1961). They have the largest range of any hummingbird in North America, nesting from w. Alberta east across s. Canada to Nova Scotia and south throughout the e. U.S. from the eastern edge of the Great Plains to the Atlantic and Gulf coasts. They winter casually along the Gulf coast from Texas to Florida and regularly from Sinaloa and Veracruz south to Costa Rica.
Status and Occurrence: Casual breeding resident and uncommon migrant with about 50 records, most from Aug and Sep in Phillips, Valley, and Sheridan Cos. Migrants occur annually in late summer and perhaps in spring but are under-reported. The earliest sightings were by Ned and Gigi Batchelder of a male near Red Lodge on 24 May 2001 (MBRC 2001-008; photo) and Robin Wolcott of a male at Westby on 24 May 2007, and the latest were by Chuck Carlson of female-like birds at Fort Peck on 18 Oct 2010 and 10 Oct 2011; the latter bird was well documented by photos. The first reliable reports for the state were from Bowdoin NWR, where the species was observed annually from 1954 to 1957, including a nest found in the summer of 1956, without further details (notes of P. D. Skaar). Ted Nordhagen saw a nest near Westby in the summer of 1973, before he kept detailed records. Several nests subsequently were reported without documentation from the Malta area. The first record from west of the Continental Divide was an adult male seen by Dan Casey near the Spotted Bear Ranger Station on 10 Jun 1988 (MBRC 1991-074). The only other records from west of the divide were birds banded near Hamilton by the Batchelders in 2008 and 2010 (see below). The Batchelders also banded three birds at Red Lodge, well south of the known breeding range, from 2001 to 2003.
The state’s only extant specimen was salvaged by Chuck Carlson at Fort Peck on 31 Aug 1992 (UMZM 17624; not 17924 as in Wright 1996). Ted Nordhagen found a dead bird at Westby on 2 Sep 1995, but it was never placed in the UMZM (see Wright 1996).
Habitat: No specific information for Montana. In most of their range Ruby-throated Hummingbirds breed in deciduous and mixed deciduous-coniferous forests, preferring forest edges rather than interiors. They also frequent orchards, gardens, and wooded parks but are scarce in heavily urbanized areas (Williamson 2001). The nest is made of plant down, spider webbing, and lichen and is placed on a horizontal limb from 1 to 15 m off the ground. The species feeds on nectar and flying insects.
Conservation: Ruby-throated Hummingbirds are not of conservation concern anywhere in their range. The BBS is not well suited to monitoring population trends, but the data indicate weakly supported increases in numbers range-wide. The global population estimate is 7.3 million birds, making this species the most abundant hummingbird north of Mexico (Rich et al. 2004). Claims that feeders delay migration have no scientific support and almost surely are not true (see Robinson et al. 1996).
Historical Notes: Cameron (1907: 390) related several second-hand reports of the species from Custer Co., including a possible nesting pair along the Powder R. in 1888 and a nest at Miles City in about 1900. Saunders (1921) questioned the reports because of the likelihood that the birds were Calliope Hummingbirds.
Contemporary Work: None, aside from banding efforts summarized below.
Banded Birds: From 2001 to 2010, Ned and Gigi Batchelder banded more than 29,000 hummingbirds in Montana. Five were juvenile Ruby-throated Hummingbirds, three near Red Lodge (female on 20 Aug 2001, males on 19 Aug and 9 Sep 2003) and two near Hamilton (male on 25 Aug 2008, female on 4 Sep 2010). None of these birds was re-encountered.
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