Hi all:
This is a heartfelt plea to all Cobirds members: Please read this, particularly if you submit data to eBird (www.ebird.org).
The widespread ABA-area taxon that we call Fox Sparrow (Passerella iliaca) has diversified into some 17 named subspecies in four groups (Thick-billed [3 subsp.], Slate-colored [4 subsp.], Sooty [7 subsp.], and Red [3 subsp.]) of which member subspecies look and sound more like each other than they do the subspecies in other groups. The form breeding in Colorado and north and west in the Rockies to se. British Columbia is schistacea of the Slate-colored group. It is not all that important to know the individual subspecies, as it is to know the groups, however. Colorado-breeding Slate-colored Fox Sparrows arrive directly on breeding grounds -- with very few migrants at non-breeding locales seen in any given spring -- in April and early May. They depart in September, again with very few being seen at locales where the species does not breed (and any found are probably migrants from farther to the NW) and most having departed the state by October. There are very few good records of Slate-colored Fox Sparrow in Colorado in winter, with the McConnells of No Name (Garfield Co.) hosting a goodly percentage of them.
There are Colorado records for individuals of just one other group, Red Fox Sparrow, which is annual in the state in very small numbers and is considered a review "species" by the Colorado Bird Records Committee (CBRC). While the vast majority of state records for Red Fox Sparrow are from eastern Colorado (particularly the eastern plains), there are two records from the West Slope, one each from Ouray and Delta counties. eBird data for the group, which do not include all accepted Colorado records can be seen at http://ebird.org/ebird/map/foxsp1?neg=true&env.minX=-114.3396295&env.minY=35.73619084934264&env.maxX=-96.7615045&env.maxY=42.17026410859879&zh=true&gp=false&mr=1-12&bmo=1&emo=12&yr=1900-2012&byr=1900&eyr=2012.
In the CBRC archives, 16 of the 23 accepted records of Red Fox Sparrow were probably fall migrants, with "arrival" dates spanning 8 October - 30 November. There are just two unalloyed winter records, a 23 December bird in Yuma County and a 4 February bird in Boulder County. Now, don't yell and wave your arms if you think that I'm overlooking dates and/or records; I'm using the official CBRC accepteds database and if those records about which you wish to scream and moan are not in there, they haven't been documented/accepted. You can always correct that oversight.
Now, onto the plea. As a reviewer of Colorado eBird reports, I see a number of entries using just the species -- Fox Sparrow. Because of the timing of those entries, I can often guess to which group the bird in question belongs. However, recall those winter Slate-colored records. When seeing one of those entries, I then have to write the observer and ask her/him to change the entry to the appropriate group (Slate-colored or Fox). If the observer agrees to do so, then that person has to open the checklist in question, delete the existing entry, and insert a new entry. But, why do we have to go through this? Why not simply enter the sighting to the group level in the first place? Please. Slate-colored and Red Fox Sparrows are, for the most part, easily separable and identifiable in the field. Slate-coloreds lack red in the head and streaking on the back. Red Fox Sparrow sports both. If one sees a bird so poorly that one cannot differentiate the two, then reviewers might wonder how one reached the Fox Sparrow conclusion in the first place.
However, the primary reason for eBird users to enter all Fox Sparrow reports to the subspecies group lies in the future. That is because there is a substantial body of evidence that the four groups represent valid species and a split may well be upcoming. When that happens, the powers-that-be at eBird Central will write an algorithm (or whatever) to elevate those entries that were reported at the group level to species level, thus retaining ones lifelist (and whatever other) ticks and, if one has recorded more than one group, gaining a lifelist tick (or two, or three). Those entries reported just at the current species level will see a devaluation of sorts, as the eBird database will not know to which new species the entry should be assigned, so will be assigned to the default "fox sparrow sp." entry, thus causing a loss of lifelist ticks. Ouch.
Finally, precision is always better than generality, so why not identify the group for any Fox Sparrow reported to Cobirds. I mean, one would not report one's Ross's Goose sighting to Cobirds as "white goose sp."!
Thanks,
Tony Leukering
Villas, NJ
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