Just saw two Cliff Swallow this morning at Wellington SWA--hanging in there ... the majority disappeared probably a month ago. Our local Barn Swallows (3-6) were last seen about ten days ago.
Thanks Gary Lefko, Nunn http://coloradobirder.ning.com/ Mobile: http://coloradobirder.ning.com/m On Thursday, September 26, 2013 10:29:57 AM UTC-6, Dave Leatherman wrote: > > So, is it just me or does it seem like Barn Swallows have been the last > swallow species standing for much longer this late summer-autumn than > usual? > > In the way of example, in the northwest corner of Grandview Cemetery in > Fort Collins there is a bridge over a ditch that hosts nesting by both > Cliff and Barn Swallows. It appears to me the Cliff Swallows were > single-brooded this year and the Barns did their normal double nesting. > Last Cliff was seen there, or anywhere else for that matter, on 4 August. > Birder's Handbook by Erlich et al says Cliff Swallows "usually have 1 > brood, sometimes 2-3." I guess the weather this year, particularly the > late spring storms and a resultant late start to nesting, determined 2013 > as a single brood year for the Cliffs. I just don't recall a year when for > essentially all of August and September if one sees a swallow, one could > assume the overwhelming possibility was Barn. Given the explosion of > aerial insects of late, it seems ironic that a major group (excepting Barn) > of insect-eaters is no where to be seen. The analogy that comes to mind > are sports fans who leave the game early, only to hear during their drive > home that the home team pulled off a record-setting comeback. Just what is > the environmental clue that dominates the decision of a species to refrain > from, or go for, an additional brood? Ditto for migration south. Is it > day-length, nighttime temps, an assessment of available food resources now > and into the near future, something else? > > I'd be interested in the observations of others about Cliff, or any other > swallow species for that matter, departing earlier this year compared to a > "normal" year, if there is such a thing in CO? > > Dave Leatherman > Fort Collins > -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/0c2d7607-c545-49c8-8c83-6c1a6a2ed988%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
