Requested in writing via their web site to be placed on their Do Not Call list; have been called four times since. Filed a complaint at https://complaints.donotcall.gov/complaint/complaintcheck.aspx.
 Dec 12th, 2010
Fourteen calls from this number, all hang-ups with no message until I started blocking it. We did join the San Diego Zoo last year, which seems to have been a bad idea, since their telemarketers seems quite persistent.
 Dec 09th, 2010
This call is indeed associated with the San Diego Zoo. If you call them the person who answers will repeat the info they typically leave on your answering machine (i.e. this is the San Diego Zoo donor services group) and they ask how they can help you. I said please remove me from your call list. They asked for the number and removed me from the list. The whole call took about 30 seconds, they did not try to sell me anything, and now (hopefully) I will no longer get a call EVERY day. I can't tell you if the removal worked for sure because I just took care of this 5 minutes ago. I guess I will find out if I get a call tomorrow.
 Mar 27th, 2010
I presume they are calling because I used to have a membership in the Zoological Society of San Diego. If they want to call endlessly, I'm more than happy to not answer and let them waste their time.
 Apr 08th, 2009
Same as below. The ID said 'San Diego Zoo', but since it was 323 area code, I didn't answer. No message was left.
 Dec 02nd, 2007
Caller ID said "San Diego Zoo", but may have been a spoof: 323 are code is in Los Angeles, not San Diego.

Did not answer, I let machine take call, but they hung up with no message.

Reported to www.donotcall.gov
 Dec 01st, 2007
they called again and started a speel about how a non profit can call so I started a retort that starts with a well the f---- you. Since they claim they can call (at dinner) I can *67 and call back
 Nov 28th, 2007