eBird is designed to take data from single-party birding outings. A single party can consist of any number of participants, as long as you are birding together as a group. So birding with friends is good, but just remember to put the correct number of observers in that field on the data entry form. Problems arise, however, when multi-party counts are aggregated into single checklists that cover very large areas. Multi-party counts should not be entered in eBird. A good example of this is when users enter Christmas Bird Count data. It is not appropriate to enter the CBC totals for the entire count circle into eBird. For starters those data are already gathered and maintained by Audubon, so there's no need for us to do it here. But more importantly it skews the eBird output toward these large multi-party counts, and gives an unrealistic representation of what one (or a single-party) might expect to find in a given day's birding in a region. To add value to the CBC, you can enter your single-party CBC counts into eBird. By doing this you increase the resolution of the CBC data by making it spatially relevant, in the process making those data more appropriate for eBird. This process extends beyond CBCs and applies to all other multi-party counts. Please enter the data into eBird in its complete richness, not in summary form, this way we get better information and so do you!
How do you define a multi-party count?A multi-party count is an effort in which multiple observers or groups of observers are assigned to bird specific territories within a larger geographic area, and then compile and combine their totals at the end. For example, in a typical CBC, birders or groups of birders are assigned territories that do not overlap, and the groups do not interact except to compile/combine numbers at the end. These compiled summary data are not appropriate for eBird, but the individual single party counts are fine.
Single parties should be within voice contact during the birding event (similar to a big day). If someone went to the bathroom and were out of voice contact for a few minutes, that is fine. However, if a group splits up and covers very different areas for a significant percentage of the total checklist, these should be entered as different checklists. If the distance between individuals is so great that you must use radios, phones or handheld devices to communicate with each other, we consider you to be in different parties and these records are best submitted on different checklists.