Spring Swallows

By Kathy Oakes

March Madness! For birders, it’s all about the returning migrants. Swallows are some of the earliest arrivals and a sure sign of spring. It is a myth that swallows always return to their breeding areas on the same date. Their arrival may vary by up to two weeks from year-to-year, depending on the advance of warming temperatures. So, the (Cliff) swallows do not reliably return to San Juan Capistrano each year right on March 19 (as tradition would have it). In recent years, the swallows have not returned to Capistrano at all, having abandoned the old mission for more upscale digs at a nearby country club.

Swallows are superb aerialists and feed on flying insects. Though they have small beaks, they have wide mouths, into which they scoop insects from the air while in flight. Swallows may also drink on the wing and even bathe on the wing, splashing briefly into the water before flying off.

​​We have six swallow species in northern Nevada: Barn Swallows, Cliff Swallows, Tree Swallows, Violet-green Swallows, Northern Rough-winged and Bank Swallows.
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Barn Swallows are our only swallow with a deeply forked tail. They have blue-black wings and back, a rufous throat, and orange under parts. They build their mud and saliva cup nests almost exclusively on man-made structures—under bridges, in culverts, or against vertical walls of buildings in sheltered areas. One can usually see them hunting over the Truckee River and over irrigation ditches. 

Barn Swallow

Cliff Swallow

​Cliff Swallows also have dark bluish backs and wings and rufous around the face. However, they are easily distinguished from Barn Swallows by their paler underparts, short square tails, dark throats, and white foreheads. Cliff Swallows also build mud nests, but theirs are elaborate  gourd-shaped structures with a small entrance hole. Cliff Swallows tend to nest in large colonies. An evening stroll under the Arlington Street  Bridge in summer will reward with great views of the colony that usually nests there. 

​Tree Swallows have iridescent blue-green upperparts, white underparts,  and a very slightly forked tail. They nest in natural or man-made cavities near water. I have seen several pairs of Tree Swallows nesting in woodpecker holes in one standing dead tree along the Truckee River. I have also seen them use nest boxes near the ponds at Rancho San Rafael. 

Tree Swallow

Violet-green Swallow

Violet-green Swallows resemble Tree  Swallows, but their white underparts extend above the eye and also well up the sides of their rump, forming two white patches that can be seen in  flight. On perched birds, the wings of  Violet-green Swallows extend beyond the tail, while those of the Tree do not. 

Our other two swallow species,  Northern Rough-winged and Bank  Swallows, nest in holes in vertical banks near water and are less frequently observed. 

So, haul out your binoculars and field guide to a local water body and study our swallows. By fall, you could become an expert at swallow ID. 

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Originally published in the March/April 2011 edition of the Pelican