Wow! They put little ultra-light back packs on four Black Swifts to try to find out where the birds winter. The amazing thing is, this technology required the researchers to RECAPTURE the birds to get the data - and they DID! They got 3 of the birds back! They must have been ecstatic!
If you delve further into the other links in the article above, you will come across the stat that there are only 210 known nesting sites, and half of those are in Colorado.
Black Swift Population Estimate
British Columbia may be the actual stronghold of the Black Swift's nesting range, though. Population estimates based on Breeding Bird Surveys from the 1990s indicate BC had 70% of the breeding Swifts.* Some believe that number to be higher, at up to 81%.
*"The population size estimates in this database correspond to those presented in the Partners in Flight North American Landbird Conservation Plan (Rich et al. 2004) and The Association of Fish and Wildlife Agencies Partners in Flight Landbird Reports (Rosenberg 2004). These estimates were derived from Breeding Bird Survey data from the 1990’s, and thus reflect average population sizes during that decade."
Black Swift population estimate
World = 30,000
Northern Rockies (bio-geographic zone) = 22,000
British Columbia (political zone) = 21,000
More about their nesting habitat
They nest behind waterfalls. The best time to detect them is just after dusk as they return from a day of insect hawking. Oh, and it helps to have a pair of night vision goggles.
Ok. Just stake yourself out at the base of a roaring, misty waterfall, preferably one in some narrow cleft up on the side of a steep mountain somewhere, and wait. Be sure you know how to find your way out in the dark, or maybe curl up in a wet sleeping bag until the sun comes around again.
Here is an article about a major survey effort of nesting sites done in 2003 in the "Pacific Northwest".
My Swift Experiences
I have seen Black Swift in my home "county" and other places. I have seen the large flocks zipping around way up high in front of an impending storm front; the Blacks up above the Vaux’s. Freaky in that light. They are so beautiful to watch! But mostly I get just a brief glimpse, and I do suspect they nest around here. I really should get off my butt and check out the local waterfall AND go up valley to add the White-throated Swift to my life list!
The best magical swift encounter
My most memorable experience with Swifts was seeing the Andean Swifts circling over Huayna Picchu, adjacent to Macchu Picchu, in Peru in early 1979.
To get to the top of Huayna Picchu at 2,720 m (8,920 ft) first you cross the narrow ridge edged by a drop of hundreds of feet down to the Urubamba River. Then you haul yourself up hundreds of rough-hewn steps cut into the rocks by the Inca. Then hike up to the tippy top of Huayna. Once there, dizzy from the exertion and altitude, you can scramble onto the top of the large boulder at the very apex of the mountain, plunk your butt down, hang on for dear life and enjoy the view.
There, surrounded on 3 sides by the Urubamba River way down in its gorge, and the fantastic ruins of Macchu Picchu laid out in front, you may catch a glimpse of the Andean Swift – as I did, as they whipped by meters from my head. It was magical. They were so fast, they barely registered in my consciousness. As fast as jet fighters, they were, and in their own element. The beauty of all existence crystalized on Earth for a moment.
(The climb down through the long small cave guided by the little local boys was pretty fantastic, too! But that is another story.)
eBird would be a good place to report your swift sightings. If you have evidence of breeding, don't forget to note that in your comments.
Good luck little Swifts! Happy hawking and enjoy your holiday in Brazil!