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The barn swallows wintering in southern Africa are from across Eurasia to at least 91°E, [21] and have been recorded as covering up to 11,660 km (7,250 mi) on their annual migration. [22] The nominate European subspecies was the first to have its genome sequenced and published.
The wire-tailed swallow is a member of the genus Hirundo, a cosmopolitan group of "barn swallows". It has two subspecies: [5] H. s. smithii was first described by William Elford Leach and K. D. Koenig in 1818. [6] Known as the African wire-tailed swallow, it is found throughout Africa. [5]
Weight: 11–16 g (0.39–0.56 oz) (to 19.5 g (0.69 oz) before migration) The song is a continuous gravelly twittering when the birds are on the wing and becomes a conversational undertone after they have settled in the roost. The harsh alarm is heard when a passing falcon, crow or other suspected predator requires combined action to drive it away
List of birds of Santa Cruz County, California. The county is in Northern California , located on the California coast, including northern Monterey Bay , and west of the San Francisco Bay and Silicon Valley .
[39] [40] In barn swallows, old mated males and young unmated males benefit from colonial behaviour, whereas females and mated young males likely benefit more from nesting by themselves. [ 41 ] Pairs of mated swallows are monogamous, [ 42 ] and pairs of nonmigratory species often stay near their breeding area all year, though the nest site is ...
The populations in the US and Canada have been found to winter in the southernmost US and further south. While this is true, the populations in Mexico and further south seem to be non-migratory, although local post-breeding movements do occur. This swallow has been found to occur as high as 2,500 m (8,200 ft) in Costa Rica. [1] [5]
Welcome swallows are good indicators of temperature, as the temperature drops lower, the less likely a swallow will be observed in the South. When swallows are around, the temperature usually does not drop below -2/-3 degree Celsius. [7] Migration may occur during non-breeding seasons for larger more reliable food sources.
The bird genus Hirundo is a group of passerines in the family Hirundinidae (swallows and martins). The genus name is Latin for a swallow. [1] These are the typical swallows, including the widespread barn swallow. Many of this group have blue backs, red on the face and sometimes the rump or nape, and whitish or rufous underparts. With fifteen ...