How should governments regulate parks, hiking trails etc during this pandemic?
By ensuring that everyone gets out of the house and spends their days using them, as much as possible, if they're at all able.

And by trusting people to follow the rules https://www.theglobeandmail.com/opinion/article-we-learn-to-fight-this-thing-together-by-keeping-parks-open/

Here's a great thread by sociologist @zeynep, whose essay on this subject I quote and link here, on the strong scientific evidence that authorities should maximize park access (incl. hiking, picnicking, sports etc) as a way of controlling a pandemic https://twitter.com/zeynep/status/1247551321164709889?s=20

And follow my long "daily pandemic walks in Berlin" thread to see full-to-the-brim parks functioning as infection-control successes. Over this 4-day weekend, the parks were jammed to the brim. Today, Berlin authorities announced they saw no infractions https://twitter.com/DougSaunders/status/1249634362640998401?s=20