Sunday, February 21, 2016

Update on Colorado and Wyoming filters

It has been more than long enough for another post on this venue, and I apologize for that for myself and the rest of the two states' eBird reviewers.  Personally, long work days and many other writing commitments can be blamed.  Of course, if I didn't go birding, I'd have more time to write about birding.

As I alluded in a previous post, eBird is interested in pursuing more and better habitat-based filter regions, rather than the current system of using geopolitical boundaries to define them.  As part and parcel of that interest, Don Jones (a member of the Wyoming review team) will be putting together a proposal for such for Wyoming as part of his undergraduate work (as the Brits would say) at university.  I have spent some time in designing such a system for Colorado, and have nearly completed a first-draft version for eastern Colorado.  Though Colorado's plains may seem to be easier to deal with in this regard than is the rest of the state, the reverse is actually true.  The extreme topography gradients in western Colorado actually preclude making small, tight filter regions (one would need 100s of the things!), so fairly large filter regions will still be the easiest way to treat that part of the state.  In eastern Colorado, however, there are numerous large reservoirs that attract a very different avifauna compared to most of the rest of the area.  In addition, the large urban area with their de rigeur tree canopy also make for very different bird habitat than found on the rest of the plains.  My current map has 26 regions defined from east of the Front Range-Wet Mountains-Sangre de Cristos Mountains line, where there are currently 20 regions, eight of which extend well up into the mountains.  eBird is not yet ready to greatly expand the number of "arbitrary polygons" used as filter-region boundaries, but when they are ready, Colorado and Wyoming will be ready, too.

Since February 2015, I have split Cheyenne and Kiowa counties out of the former Southeast Region into their own regions, bringing us to 39 current Colorado eBird filter regions, and with the Southeast Region no longer named such, as the remaining multi-county region is now titled Bent and Prowers.  I had plans to split those last two counties, but have decided to spend the necessary time on designing arbitrary polygons, instead, which will (hopefully soon) negate any effort to make individual filters specific to Bent and Prowers counties.

Finally, I continue to fine tune existing filters, which may cause some to many data that may have resided comfortably in eBird for years to suddenly get flagged.  Please do not be alarmed when you receive a request from one of us regarding a sighting from last year or from five years ago.  This is a normal process, one that is greatly aided by the great increase in amount of eBird data available to analyze how filters might be made more precise.  That is, thanks to you, eBird becomes stronger and stronger in its ability to define geographic and temporal bird occurrence in Colorado and Wyoming and the rest of the world.