I recommend Scammons Lagoon at Guerro Negro. Avoid the tours; they aren't allowed into the lagoon with the mothers and babies. Instead, drive out to the lagoon and go with one of the ponga drivers. The Mexican government protects the lagoon with very strict policies, and commercial tours, like Eco-Tours, can't come in; they have to stop at the mouth of the lagoon. In the lagoon, you'll see nursing circles (moms getting together so some can rest while others watch the kids--babies don't sleep at all) and maybe swimming school (moms make the babies swim to the mouth of the lagoon each day against the tide to build up their strength for the trip north. Babies are often too tired to get back so they ride on their moms). It's a wonderful experience to be there.
