Maybe for the future, they could notify selected licenses in advance at the time of purchase. Then a monthly email reminder to fill it out for the previous month while it's still fresh?
Yeah, DFO's Internet Recreational Effort and Catch (iREC) survey assigns you a calendar month to complete for: May for me this year.
Perhaps ISEA might get higher participation/larger sample size and more accurate data if the survey was for a month, not a year, and not so onerous to complete.
Then again, I'm sure smart people designed the ISEA survey, and my statistics expertise is limited to an undergrad class or two!