I wasn't there so don't know.  What I do know is that despite six decades of TNR, the UK stray & feral cat population has nearly doubled--from 4.1 million in 1965 to 9.1 million today.  TNR is a complete and utter failure.  It doesn't reduce unconfined feral cat populations anywhere.  That's why three decades-old feral cat colonies are commonplace in CA, OR, FL, HI, NJ, NY, DC and many other parts of the lower '48.  I want to keep the same thing from happening here.  I don't want native Alaskan wildlife replaced with a bunch of filthy cats.