From their iNat profile: This account is being used for identifying and annotating - I do not plan to add many observations to this account.
I think that indicates it is a second account specifically for the purposes of the project.
I think I must be extremely confused about projects, though. Are project members unable to dialogue on a project page itself? I.e is that the need for a thread on the forum specific to project members only?
(Asking it here because I am not a member of the project and the most recent thread is clear about whom they wish to use the thread and for what.)