We can always use more data, especially from new contributors -- members and non-members alike. We need data both for the more populated areas and for the "empty squares" for which we have no data at all -- Ontario is a big place! And data on rare species is nice, but so is data for the common species. Lots of data is required to document where each species is found in Ontario and, for each area, the flight period and number of broods per year. Records for past years are also welcome.
If you are putting butterfly records on iNaturalist.ca or e-butterfly.org, your are already contributing data to the atlas; every year we download this data and include it in the atlas. To avoid duplicates in the atlas, use only one of these two sites, or check with us about a safe way to do both.
iNaturalist includes an Ontario Butterfly Atlas project; contributing to that makes your Ontario butterfly observations more easily viewed by others, and others are more likely to add identifications to your observations.
You can also send us a spreadsheet of your data -- but, where it hard to be sure of the species, uploading one or more photos to the two butterfly-record websites is useful.
For spreadsheets, each record should include the following data: species name; observation date (year, month, day); observer(s); county, region or district (see list here); location (in words, and preferably also the lat-long); adults (the number, or comments like “a few”, “several”, “many”); immatures (e.g., 2 caterpillars); and record type (specimen, photo, sight). Begin by using the Basic Spreadsheet and instructions. Experienced users may wish to use the Advanced Spreadsheet and instructions.