Once commonplace, now considered barbaric - the tide has changed on the exploitation of wild animals in circuses. The time will come for zoos, too.
It is important to recognize that we are still a long way from reaching the same level of public consensus on zoos that was reached long ago in relation to circuses (consensus in the U.K. at least). We are under no illusions that if we call for a boycott today, the zoos will be forced to shut their doors tomorrow as their car parks remain empty and the visitors stay away. People will continue to visit zoos for years to come while we work hard to win more and more people over to "our side" of the argument.
So, while I am not saying that boycotting zoos will have no impact whatsoever when carried out on an individual level, our calls to stay away from zoos are part of our "long game".
Like ants, we cannot impact long-standing institutions if we act alone but we need to start somewhere. How about we act as individuals and then encourage our friends to do the same? What if those friends tell their families? The status quo doesn't change overnight and so no animals will starve to death as a direct result of you choosing to boycott zoos. But, by boycotting zoos, you immediately become part of the gradual shift in favour of the animals. We've seen it happen with circuses and we can do the same with zoos. We just need to play the long game.