Yesterday I was out driving around a sleeping baby before the two of us took a walk around the OSU wetlands, and I noticed a good number of Common Nighthawks (some in small flocks; maybe family groups??) over the neighborhoods between the Scioto and Olentangy rivers, and over the OSU Wetlands. I saw a total of 22 over about a 2 hour period and all were flying north: 6:30-7:15pm: 1 singelton and one group of 3 seen while driving around. 7:15-7:35pm: 10 over the OSU Wetlands in 2 groups; the first group of 6 flew over around 7:15 and then a second group of 4 flew over 5 minutes later, also heading north up the river valley. 7:45-8:25pm: 7 over the OSU Wetland in 2 groups; 1 high over the river around 8:10pm and a second group of 6 at 8:25pm high over the wetlands. When I returned home (north of Kenny Rd. and Ackerman) at 8:30pm another singleton was seen flying north over our neighborhood. The fact that all 22 of these birds were very deliberately heading north was a bit unexpected. Perhaps there's a staging ground somewhere up north? Maybe near one of the reservoirs north of Columbus (Delaware or Alum Creek)? In any case, it looks like they're starting to aggregate in preparation for their long trip to some (relatively unknown) wintering location in or beyond the Amazon basin. If we can figure out where Black Swifts spend the winter, it'll only be a matter of time before someone straps geolocators on a few CONIs too. :-) Here is some of the Birds of North America species account for Common Nighthawk relevant to fall migration: *Timing And Routes Of Migration: Fall* *U.S. and Canada*. Because fall transients commonly travel in flocks, they are more easily detected than spring transients. Rare fall migrant in extreme se. Alaska (Armstrong 1995). Mean fall departure from Okanagan, BC, 18 Sep (range 29 Aug–30 Sep, n = 16; Cannings et al. 1987). In Oregon, fall migration begins late July, peaks early September, with stragglers through early October (Gilligan et al. 1994). In California, transients noted most frequently after mid-August, but rare after mid-September, with stragglers recorded as late as mid-October (Small 1994). Transients recorded in Arizona deserts mid-August (Bryant and Bryant 1945). Southerly flights observed 23 Jul in Saskatoon, Saskatchewan (SK) (Wedgwood 1973). Transients noted in S. Dakota primarily mid-August with latest records during first week October (S. Dakota Ornithol. Union 1991). In Missouri, fall migration peaks late August or early September with stragglers late September to mid- or late Octber (Robbins and Easterla 1992). Transients peak in Massachusetts late August to early September with stragglers through late October; most observed in Connecticut River Valley with counts decreasing toward coast (Veit and Petersen 1993). Transients recorded in Cape May, NJ, from first week August through third week October with peak during first half September; transients virtually absent from barrier islands off coast (Sibley 1993). In Florida, fall migration detected from mid-July through October, with stragglers recorded through late November (Stevenson and Anderson 1994). ... *South America.* Information sketchy for this area. Species rarely observed at any season west of Andes or in ne. South America from Trinidad and Tobago (ffrench 1991), Guyana, Surinam, and French Guiana through ne. Brazil (R. Ridgely pers. comm.), although single specimens have been collected from Curaçao (22 Oct 1955) and Bonaire (2 Oct 1982) in the Netherlands Antilles off the ]northern coast of n. South America. Southbound transient “nighthawks” (which may include Antillean Nighthawk) are irregular in Netherlands Antilles (Voous 1983). Available records indicate that transients pass through Colombia (late Aug–late Nov; Hilty and Brown 1986) and Venezuela (Meyer de Schauensee and Phelps 1978) and then east of Andes through w. Amazonia to reach their primary “wintering” grounds, probably reversing this path during their northward flight. Transients observed at Manaus, n.-central Brazil, 5 Oct–8 Dec (Stotz et al. 1992); Fuerte Olimpo, Paraguay, by 27 Oct (Hayes et al. 1990); and in Rio Grande do Sul, se. Brazil, by Oct (Tampson 1987). ... *Migratory Behavior: Fall Departures* In U.S., more likely to form large flocks during fall migration than during spring. In Ontario, groups of up to 550 individuals (Ewins 1993), with 706 individuals flying over Toronto in 45 min on 31 Aug 1944 (Parker 1983). Up to 1,000 individuals observed in Manitoba and in Vancouver, BC (de Graff 1978), Michigan (Brewer et al. 1991), Wisconsin (Tessen 1987), Texas (Gross 1940), Arizona (Bryant and Bryant 1945), and New York (Bull 1985); 16,496 individuals observed in Minnesota on 16 Aug 1986 (Tessen 1987). Local flocks gather with traveling migrants, forming large horizontal rectangle of birds, 8–10 birds wide and 15–20 birds long; migratory flight rapid, unison wingbeats, with no apparent leader (Rust 1947). Engage in group flight several days before migration: close formation, 2.4–3.1 m apart horizontally and vertically (Rust 1947). During migration may fly close to the ground, apparently foraging on insects (Gross 1940), but probably feed on insects at higher altitudes as well. Good birding, Paul Hurtado Columbus, OH ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. 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