I was down by the beach in La Jolla a couple weekends ago and signed up for their mailing list, partly because I believe in what they're doing (keeping public property and open space accessible for everyone), partly in retaliation for the seal vigilante who was also standing there and gave me a pretty smug comment when I decided not to sign up on his list. (As it turns out, given the attitude they project, "seal vigilante" is to be a pretty apt description. I've been a Sierra Club member in the past but I don't support or even really understanding what the vigilantes are doing.)
Bottom line, harbor seals are not even close to endangered, they're not even truly native to San Diego and the Children's Pool was set aside specifically...for children! My cousin is a San Diego native and learned to swim there, and now he can't do the same for his own sons. To preserve it for families now and for future generations, visit Friends of the Childrens Pool and sign up for their email list.