I'm late to this discussion, but here's some more impressions of this bird in westish Arapahoe Co....
In early-March 2016, I moved to west Centennial (Arapahoe) from the Cap Hill neighborhood of Denver. Immediately, I was struck by the relative absence of House Sparrows.
In Denver, they seemed the default small bird around neighborhoods, with House Finches a close second. This was my impression, at least; I haven't looked at checklists to support it, however. At Denver Botanic Gardens, where I spent most of my birding time, House Sparrows seemed slightly scarcer and around in small numbers than House Finches.
In Centennial, I was thrilled that, initially, I didn't see House Sparrows in my yard. About two weeks after moving in, I saw my first. I see them sporadically around my yard – though certainly more often than I report them. But they're by no means a daily sight.
Around Centennial, I regularly see a flock of House Sparrows at deKoevend Park, where there's a particular bush, near a residential feeder, that's usually filled with 15-20 House Sparrows. A few are sometimes near the Goodson Recreation Center and the pedestrian bridge that crosses the Big Dry Creek behind the Rec Center's Parking lot. A pair is often at the top of the hill beyond that pedestrian bridge.
In around 150 trips or so to Marjorie Perry Nature Preserve, I've never seen a House Sparrow. I'm not the only one: there are only two eBird reports of this bird at the preserve and my understanding is that those reports are of birds in the residential neighborhood surrounding the preserve, not the preserve itself.
House Sparrows are around west Centennial. I might get some along the Big Dry Creek Trail or Willow Springs Open Space. But if I were doing a "big day" in my home birding circle, I could miss them unless I made a special trip to that single bush in deKoevend.
More compelling than my impressions, though, is what eBird data says. Assuming I haven't made any mistakes in compiling this data (though I may have…don't quote me on this), here's eleven years of eBird data for Arapahoe County, summarized so as to show the percent of all checklists that include House Sparrows and the average count of House Sparrows on those checklists that include the bird. This is 25,000+ checklists worth of data.
The table shows that, over the past ten years, House Sparrows were reported most frequently about five years ago. But, when seen, they seemed to show in higher numbers a decade ago. This year, House Sparrows are reported less frequently than at any point over the past decade (though perhaps these numbers increase as spring, summer, and fall birding come on?). And relatively few are seen when the bird is in fact reported.
Keep this in mind: I just summed and averaged numbers. A more careful analysis would take into account all sorts of other things – effort, distance covered, the fact that eBird use has changed dramatically over time, etc. And this is not nearly as sophisticated an analysis as Doug Eddy did for Colorado Springs with the CBC data.
| HOSP | Percent of Checklists that Include HOSP | Average Count (When Present) |
| 2008 | 11.2 | 8.9 |
| 2009 | 15.7 | 9.2 |
| 2010 | 12.1 | 7.3 |
| 2011 | 16.4 | 5.9 |
| 2012 | 15.2 | 7.2 |
| 2013 | 20.4 | 6.8 |
| 2014 | 18.7 | 5.3 |
| 2015 | 16.8 | 6.2 |
| 2016 | 12.8 | 5.4 |
| 2017 | 13.2 | 5.3 |
| 2018 | 8.4 | 4.9 |
- Jared Del Rosso
Centennial, CO
On Monday, April 9, 2018 at 11:48:40 AM UTC-6, ouzels wrote:
Denver Audubon just received a call from a woman in Lafayette with a unique subject: where have the House Sparrows gone?
She says she used to have as many as 80, but now she sees only a pair or two, sproadically. They check out her yard and continue on somewhere else. Have any of you experienced a diminishing numbers of House Sparrows?
Hugh Kingery
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