the leash part is new

Regarding the above question.. Can someone explain the regulations or where I might find them? I sense the greater majority of beach users would favor leashes for all animals. (No, not just those other, bigger dogs than mine).
Are the rules posted on the beach?
Dear tourist: Show me a travel site that doesn't advise leaving your pet at home for it's sake and that of your fellow travelers.

Here is the travel site that is actually made by someone who lives in the travel destination and that does NOT advise tourists to leave their pets at home. Almost every other travel site is made and run by people who do NOT live in the destinations they try to sell vacation packages for. But then again, I'm not trying to sell anything to any of you.

Can't show you the law because (1) it's a book written in Spanish, and (2) the rules are being made up as we go along. First, all pets were banned from all beaches but then most all of the local beachfront restaurant operators (except for one) came out against the law as well as numerous lodging operators and hundreds of concerned locals. So the law at this point, like most laws in Mexico, is not being applied. It was hastily written and incorporated into local regs for political reasons and without any public consultation or input from locals, businesses or tourists.

If you prefer beaches without pets then there's Ixtapa's Playa El Palmar, about as soulless and dull a beach as I've ever seen in my life.