Hilda, when you report distance for eBird, you are not supposed to include backtracking. So, it’s not the distance that you walked, but the distance that you covered.
From: <carolinabirds-request...> [mailto:<carolinabirds-request...>] On Behalf Of Hilda Flamholtz (via carolinabirds Mailing List)
Sent: Saturday, April 15, 2017 10:33 AM
To: Christopher Hill
Cc: Kent Fiala; <carolinabirds...>
Subject: Re: eBird reporting
OK - this is good to know. I did a 7 mile Christmas Bird count day that was all walking in one park. I hate to think that it didn't count, but lesson learned. In this park, there is a central loop around Congaree Creek with two tails breaking off the loop. There was some retracing of steps to get it all in but not recounting the same birds on those pieces, of course. (Timmerman Trail in Cayce, SC) We birded from like 7am to 12:30 or 1 in the one park. I think if you put a dot in the center of the park - it is definitely not more than 5 miles diameter.
Should I have just broken it up into 2 time chunks to have less distance in each? Or put 5 miles thinking not so much of how much I walked but more about the total range of the area?
On Fri, Apr 14, 2017 at 3:18 PM, Christopher Hill <Chill...> wrote:
I deleted the specific checklist Kent was responding to, but I will agree with him. When looking for areas of Loggerhead Shrike concentrations in South Carolina, I have been a bit frustrated by ebird lists that had high numbers, but then turned out to be from a 200 mile drive that started or ended in another state! The dot on the map had basically no relationship to the birds counted. That’s an extreme example, but what Kent says is true. Outliers like that get incorporated into maps and other data processing and distort the picture.
On Apr 14, 2017, at 3:05 PM, Kent Fiala <carolinabirds...> wrote:
Traveling counts have proven to be the most effective type of observation for modeling bird populations at large scales. By doing these counts birders often detect a good proportion of the birds in a given habitat. It is critical, however, that your traveling counts not be too long. Our analysts are able to effectively use traveling counts that are ≤5 miles. Most birding that is conducted on foot easily falls within this window, but traveling counts by car can often be longer. Please consider breaking up your long traveling counts into shorter distance ones. It's best if these shorter counts are in a relatively consistent habitat, or does not pass through habitats that are too different. For example, a logical point to break a longer route into segments would be a transition between forest and farmland, as the birds found in these two habitat types are vastly different. Doing so would make information associated with each location — such as vegetation information from satellite images — more informative. Plot your location at the center of the area traveled, not at the start point or end point.