That job is usually performed by the American Humane Association's Film and Television Unit - they're the ones who allow films to use the disclaimer "No animals were harmed in the making of this motioin picture". Rules include "precautions should be taken to minimize the number of bugs flying into the lights." when insects are being filmed! Read
http://www.slate.com/id/2117565/ for more info.
Most of the other jobs that PETA credits itself for are much better performed by the SPCA and it's equivalents outside the US. They regulate animal cruelty and prosecute law-breakers.
This then leaves PETA as a half-arsed lobby group who's only milieux is self-aggrandising publicity stunts of questionable morality.