On November 28, 2025 an unusual bird accidentally entered a building at the Fish Hatchery just west of Fredericton. Staff carefully caught and released what they thought was a Cliff Swallow. Fortunately they quickly photographed it before release. It didn't take long before an experienced birder recognized this visitor as something unusual. It was later confirmed as a CAVE SWALLOW (Petrochelidon fulva).
Cave Swallows are very rare fall visitors to our area, usually along the coast. They look very much like Cliff Swallows so are often overlooked. Following is a comparison of the two species.
This description assumes the reader knows what a Cliff Swallow looks like. The Cave Swallow is slightly smaller than the Cliff Swallow. It appears to have a shorter head and a more rounded body. Its colour looks more washed out. Its forehead and throat patch are reversed in colour from that of the Cliff Swallow. In the Cave Swallow the forehead patch is dark cinnamon (or at least not white) and the throat is buffy. In the Cliff Swallos the forehead patch is white and the throat is dark cinnamon. The rump patch in the Cave Swallow is slightly darker than that of the Cliff Swallow, more cinnamon coloured. This makes the rump patch less contrasting in the Cave Swallow than in the Cliff Swallow. In summary, remember the Cave Swallow is dark forehead/light throat vs. the Cliff Swallow with light forehead/dark throat.
In the photo above note the dark forehead patch and the light throat.
The Cave Swallow's normal range is far from here. It breeds in SE New Mexico, south and central Texas and in the extreme south of Florida. It is a year-round resident of northern Mexico, the Yucatan peninsula, and some of the West Indies. It winters in the tropics. Its preferred habitat is open country near caves and cliffs.
Cave Swallows are similar to Cliff Swallows in their nests, made of clay pellets and mud and lined with grass and feathers. The nest is cup shaped and plastered to the side of a cave, sinkhole or a bridge or sometimes a building. Three to five white eggs marked with brown are incubated 15 to 18 days by both adults. Like Cliff Swallows, Cave Swallows have an affinity for concrete and the abundance of concrete abutments, girders and beams in our bridges and buildings make good nesting sites. This has undoubtedly led to the increase in the population of the Cave Swallow in recent years. One of the largest colonies nests in Carlsbad Cavern in New Mexico where they enjoy the dark cavernous habitat.
Cave Swallows feed on insects while on the wing. They often feed with flocks of other swallows and prefer to feed high up. They glide a lot and their flight is a bit more fluttery than that of the Cliff Swallow. The song of this species is like that of the Barn Swallow but more muffled.
The Texas subspecies of the Cave Swallow is noted for its wandering behaviour, especially along the Atlantic seaboard. It is likely the one that periodically appears here. It also wanders to the eastern Great Lakes. Also, it rarely has been know to appear in Atlantic Canada in the spring.
So, if you see an out-of-season swallow here you must first look carefully at the shape and the pale rump and you will first think it is a Cliff Swallow. Then notice the washed-out colour and watch for the key features, the forehead patch and the throat. Cave Swallow = dark cinnamon forehead (or at least not white) + pale throat.
The population of the Cave Swallow was rated as Least Concern in 2000. It is estimated to be about 9 million individuals.
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