Can the existence of Zoos be justifiable nowadays

Is there any jus¬ti¬fi¬ca¬tion for keep¬ing ani¬mals, liv¬ing beings, in strict cap¬tiv¬ity? A question that cre¬ates debate right at the moment of pos¬ing it. Many peo¬ple have strong feel¬ings against keep¬ing ani¬mals in cap¬tiv¬ity, and would like to ban the con¬cept of “Zoos”. Oth¬ers don’t give it any atten¬tion as long as they are enter¬tained when vis-it¬ing the Zoo.
The mis¬sion of well-respected Zoos, those accred¬ited as mem¬bers of the global zoo¬log¬i¬cal asso¬ci¬a¬tion (WAZA) and/or regional asso-ci¬a¬tions such as EAZA, AZA and ZAA, offi¬cially addresses con-ser¬va¬tion, research, edu¬ca¬tion and recre¬ation. The first two with regard to ecosys¬tems and (endan¬gered) ani¬mal species, and the lat-ter two aim¬ing at the Zoos’ vis¬i¬tors.
Since recre¬ation means for the aver¬age vis¬i¬tor that he wants to have a good time when vis¬it¬ing the Zoo, this is a problem that Zoos have to deal with. To get the mes¬sage across about the peril sit¬u¬a-tion of Planet Earth, the need for bet¬ter pro¬tec¬tion of ecosys¬tems and sav¬ing endan¬gered species, together with bet¬ter under¬stand¬ing of these ecosys¬tems and species, edu¬ca¬tion is the per¬fect instru-ment of course.
For chil¬dren the recre¬ational part (enter¬tain¬ment) can sup¬port the more seri¬ous aspects of the Zoos’ mis¬sion. In other words, learn¬ing can be made fun. And many Zoos have suc¬ceeded in devel¬op¬ing entertainment/education pro¬grammes for chil¬dren that incor¬po-rates the seri¬ous mes¬sage there is to tell. Whether or not this mes¬sage is going to stay after the visit to the Zoo is under debate.
Many Zoos have estab¬lished excel¬lent ways to attract children’s atten¬tion, includ¬ing edu¬ca¬tion pro¬grammes for the young. But what about the adults, the par¬ents and grand-parents that want to be edu¬cated beyond the basic infor¬ma¬tion their children are pro¬vided with. Not all adults set¬tle for some of those colour¬ful car¬toon¬ish Zoo web¬sites or infor¬ma¬tion leaflets, nor