Source: Angela Bennett
Source: Kellee Knutson
This article contains a somewhat graphic video - you can skip the video and read the article to learn about this news event from February 10, 2014 if you choose.
Blackfish is a documentary about captive killer whales. Here is an article about this documentary which will give you an idea about a current news event relating to the arguments on the topic of zoos (in this case, Sea World).