Re:[cayugabirds-l] Swan count for CBC
Last night I made of a Google map of the swan flock information reported to the listserv. I updated the trajectories and markers this morning adding some deductive/speculative text. Cayuga Bird Club 2013 CBC Swan flock map (click markers to read text – if you have a Google acct and log in you can add information to the map) The evidence suggests some flocks were double and even triple counted, but as Ken pointed out there are still some things that don’t add up. Two pieces of information that would help complete the picture would be more description on the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s group. I don’t have that flock on the map and it doesn’t seem like it could have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were plausibly the same flock. Also, any swan flock information from section V (Sandy’s section) would be useful in determining whether the 40 seen there were unique flocks or flocks that had already been counted. Anyone else who saw swan flocks on January 1st, please have a look at the map and see if your information matches or suggests additional unique flocks. As of now there is a fairly solid case for a minimum of 163 southbound swans on count day. This presumes that swan flocks that exited the city of Ithaca in southbound flight didn’t return. Bill E -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/cayugabirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
Re: Re:[cayugabirds-l] Swan count for CBC
Last night I made of a Google map of the swan flock information reported to the listserv. I updated the trajectories and markers this morning adding some deductive/speculative text. Cayuga Bird Club 2013 CBC Swan flock map (click markers to read text – if you have a Google acct and log in you can add information to the map) The evidence suggests some flocks were double and even triple counted, but as Ken pointed out there are still some things that don’t add up. Two pieces of information that would help complete the picture would be more description on the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s group. I don’t have that flock on the map and it doesn’t seem like it could have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were plausibly the same flock. Also, any swan flock information from section V (Sandy’s section) would be useful in determining whether the 40 seen there were unique flocks or flocks that had already been counted. Anyone else who saw swan flocks on January 1st, please have a look at the map and see if your information matches or suggests additional unique flocks. As of now there is fairly solid case for a minimum of 163 southbound swans on count day. This presumes that swan flocks that exited the city of Ithaca in southbound flight didn’t return. Bill E -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/cayugabirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
RE: [cayugabirds-l] Swan count for CBC
This discussion has been interesting to “watch” as it has unfolded. I certainly understand the desire folks have to make the counts as accurate as possible. Still, I wonder how all this adjusting of the numbers after-the-fact for just one species, and for just one year, influences the utility of the data for comparative purposes from year to year. Given the year-to-year variability of the weather and its uncertain influence on both long-distance migration (e.g., of swans) and local movements (from and to feeders), I wonder if it simply makes the most sense to keep doing things the way they always have been done -- recognizing and even accepting that various species will be more or less likely to be affected in any given year with respect to whether they are double or triple counted, or undercounted. If the purpose of the count (at least one of the major purposes) is to be able to examine long-term trends, then it seems that consistency of methodology from year-to-year should trump our noble attempts to improve within-year accuracy. How far do Chickadees and other feeder birds move around on cold, blustery days like we had on January 1st? The 6 feeder watchers in my neighborhood probably all had the same individual birds visit their feeders. Seems rather endless to try to figure out how to deal with all the uncertainty in the data collection. I know the inquisitive scientist within me loves the challenge of trying to reduce that uncertainty, but a reduction in this kind of uncertainty probably will not enhance the utility of the data for its intended purpose. Besides, the discoverer within me loves being out in horrible conditions just seeing what I can find, recognize, and learn. I suppose it’s probably the same - to a lesser or greater degree- for everyone who looked for birds on the First. Have fun, Jody Jody W. Enck, PhD Human Dimensions of Natural Resources Cornell Lab of Ornithology From: Bill Evans Sent: January 4, 2013 10:05 AM To: CAYUGABIRDS-L Subject: Re:[cayugabirds-l] Swan count for CBC Last night I made of a Google map of the swan flock information reported to the listserv. I updated the trajectories and markers this morning adding some deductive/speculative text. Cayuga Bird Club 2013 CBC Swan flock maphttp://maps.google.com/maps/ms?ie=UTFmsa=0msid=208086491899212349523.0004d26dc6966e4c7c382 (click markers to read text – if you have a Google acct and log in you can add information to the map) The evidence suggests some flocks were double and even triple counted, but as Ken pointed out there are still some things that don’t add up. Two pieces of information that would help complete the picture would be more description on the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s group. I don’t have that flock on the map and it doesn’t seem like it could have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were plausibly the same flock. Also, any swan flock information from section V (Sandy’s section) would be useful in determining whether the 40 seen there were unique flocks or flocks that had already been counted. Anyone else who saw swan flocks on January 1st, please have a look at the map and see if your information matches or suggests additional unique flocks. As of now there is a fairly solid case for a minimum of 163 southbound swans on count day. This presumes that swan flocks that exited the city of Ithaca in southbound flight didn’t return. Bill E -- Cayugabirds-L List Info: Welcome and Basicshttp://www.northeastbirding.com/CayugabirdsWELCOME Rules and Informationhttp://www.northeastbirding.com/CayugabirdsRULES Subscribe, Configuration and Leavehttp://www.northeastbirding.com/CayugabirdsSubscribeConfigurationLeave.htm Archives: The Mail Archivehttp://www.mail-archive.com/cayugabirds-l%40cornell.edu/maillist.html Surfbirdshttp://www.surfbirds.com/birdingmail/Group/Cayugabirds BirdingOnThe.Nethttp://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBirdhttp://ebird.org/content/ebird/! -- -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/cayugabirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
Re: [cayugabirds-l] Swan count for CBC
Thanks, Jody, for a really excellent post! Birds have a bad habit of flying! This leads to their having a propensity for being in two or more places nearly at once. Behind the old NCR building on 96B, we flushed a Red-tail. A few minutes later we saw another gliding overhead in the opposite direction. A few minutes after that there was one flying back and forth over the trees to the south. We surmised it was the same bird and only counted/reported the one. In the same spot, at one end of the parking lot we observed 2 Yellow-rumps. Later, a hundred yards to the north, we observed another. I may (likely) have been one of the first two, but I thought it looked like a third and counted it that way. All 3 responded to the chickadee/screech owl mobbing call recording, so certainly there is a good chance that one of the earlier Y-rs flew to the new area to see what was going on. The counters ultimately make choices about how many of what they are seeing, and the factors which dictate these choices seem to me to be as variable (and ephemeral) as those which determine which flock of Tundras was seen and how many times. And since some of those swans were counted in area VI, why wouldn't I, as area coordinator, want to have them in the sector total? I mean, it kind of beats sitting there at the lab during the compilation and saying NONE to every other species enumerated! Yes, I know that NONE is totally valid data, but still, we are not machines, we are human beings. (and we want birds!) Asher On Fri, Jan 4, 2013 at 11:37 AM, Jody W Enck j...@cornell.edu wrote: This discussion has been interesting to “watch” as it has unfolded. I certainly understand the desire folks have to make the counts as accurate as possible. Still, I wonder how all this adjusting of the numbers after-the-fact for just one species, and for just one year, influences the utility of the data for comparative purposes from year to year. Given the year-to-year variability of the weather and its uncertain influence on both long-distance migration (e.g., of swans) and local movements (from and to feeders), I wonder if it simply makes the most sense to keep doing things the way they always have been done -- recognizing and even accepting that various species will be more or less likely to be affected in any given year with respect to whether they are double or triple counted, or undercounted. If the purpose of the count (at least one of the major purposes) is to be able to examine long-term trends, then it seems that consistency of methodology from year-to-year should trump our noble attempts to improve within-year accuracy. How far do Chickadees and other feeder birds move around on cold, blustery days like we had on January 1st? The 6 feeder watchers in my neighborhood probably all had the same individual birds visit their feeders. Seems rather endless to try to figure out how to deal with all the uncertainty in the data collection. I know the inquisitive scientist within me loves the challenge of trying to reduce that uncertainty, but a reduction in this kind of uncertainty probably will not enhance the utility of the data for its intended purpose. Besides, the discoverer within me loves being out in horrible conditions just seeing what I can find, recognize, and learn. I suppose it’s probably the same - to a lesser or greater degree- for everyone who looked for birds on the First. Have fun, Jody Jody W. Enck, PhD Human Dimensions of Natural Resources Cornell Lab of Ornithology *From:* Bill Evans *Sent:* January 4, 2013 10:05 AM *To:* CAYUGABIRDS-L *Subject:* Re:[cayugabirds-l] Swan count for CBC Last night I made of a Google map of the swan flock information reported to the listserv. I updated the trajectories and markers this morning adding some deductive/speculative text. Cayuga Bird Club 2013 CBC Swan flock maphttp://maps.google.com/maps/ms?ie=UTFmsa=0msid=208086491899212349523.0004d26dc6966e4c7c382(click markers to read text – if you have a Google acct and log in you can add information to the map) The evidence suggests some flocks were double and even triple counted, but as Ken pointed out there are still some things that don’t add up. Two pieces of information that would help complete the picture would be more description on the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s group. I don’t have that flock on the map and it doesn’t seem like it could have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were plausibly the same flock. Also, any swan flock information from section V (Sandy’s section) would be useful in determining whether the 40 seen there were unique flocks or flocks that had already been counted. Anyone else who saw swan flocks on January 1st, please have a look at the map and see if your information matches or suggests additional unique flocks. As of now there is a fairly solid case for a minimum
Re: [cayugabirds-l] Swan count for CBC
Jody, The concept of avoiding double counting is implied in the nature of the CBC, and there is a spectrum in the level of attentiveness in avoiding double counting for different species, different locations, and by different birding parties. The key idea amidst all the variables, as you note, is maintaining the utility of the data for long-term interpretation of changes, and this involves consistency of monitoring (even if it is rough around the edges). Of course there is no realistic means for preventing double-counting of chickadees in a neighborhood with multiple feeders, but every year there is a concerted effort not to double count waterfowl at Stewart Park -- the highest tallies are typically taken instead of adding each observer’s sightings, or as I recall, one person is designated to count geese, gulls etc. on the lake. Swans have only been documented on (I believe) 6 Ithaca CBCs in the past 100+ years, all in the last two decades. Whatever count total is used, this year is our record high count. I don’t recall any years like this one when we had multiple flocks in passage, so the previous count totals were likely highly accurate and not subject to being double-counted. However, the evidence suggests that a section-added count of ~400 is a 100% overestimate. Using the section-added total would likely be a gross deviation from the status quo with regard to the accuracy of past swan counts on our CBC. Like the coordinated effort at Stewart Park to prevent multiple waterfowl counts, the swan tally could be corrected with a bit of coordination in observations this year and foresight in future years (i.e., noting flock size, location, trajectory, and time). So, while I generally agree with the importance of maintaining the status quo in counting procedures, I don’t agree with projecting the status quo of a section-added count (i.e., for chickadees) on swans. Asher, section counts would not be denied their birds. As one can see from the map, section counts in fact help ascertain the accuracy of the migration tally. Bill E The evidence suggests some flocks were double and even triple counted, but as Ken pointed out there are still some things that don’t add up. Two pieces of information that would he -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/cayugabirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
