1 - With the potential for more than one person visiting a priorty block, I assume it’s always best to submit a complete checklist, but what about the need to voucher a species if someone has already submitted one?
It is definitely best to do complete checklist, for both e-Butterfly, and for you birders, eBird. There is so much more that can be done with complete checklists when we are analyzing data. And, the best thing you can do for e-Butterfly checklisting, not just for the atlas, is to photo-voucher as much as you can for each checklist. Photo-vouchers are something that anyone can use to verify things now and decades from now. This instills confidence for users of the data far into the future. Even for common species it is great to have a quick photo voucher. I know, it can be onerous sometimes, but I personally really try to photo-voucher for each and every checklist I do. And I am not talking about amazing macro photos here, just plain ordinary photos, sometimes even blurry are fine, that allow another person to also ID your observation.
2 - Where on the e-butterfly record does one enter the Block ID? - in notes? I know that GPS locations are generated when establishing a location. Is that enough?
Indeed, that is enough. You do not have to put the block name anyplace. Each checklsit you do in eButterfly has a latitude and longitude and that is all that is needed. Now, if you want to put the block name in the checklist notes, or any other information for yourself, that is fine.
- . Is there a preferred protocol for adding weather info in surveys, such as temperature, sky conditions, and wind? I’ve just been adding this info as “Remarks” to my checklists.
There is no protocol for recording weather. I sometimes add notes about it in the checklists comments, but it will likely go unused when a data scientist is using tens of thousands of records. What will likely happen in that case, is they would use weather data from NOAA if needed. Collecting weather data for this kind of work is fraught with user problems.