This is a rly easy achievement.
Use one of the 1997 skins (works with every 1997 skins) build a group of 5 stegosaurus and put them in a paddock with 1 feeder. Wait until the feeder is nearly empty. Create a save game file if something will go wrong at this point. Then send 1 ranger to refill it and follow him with a 2nd ranger jeep and stay in a short distance to him during he refills the feeder.
During the refill the stegosaurus will get mad and some of them will roam around panical. Some seconds later one of them will attack the refilling jeep.
Shoot a photo when the stegosaurus swings his tail to hit the jeep and the achivo will pop some seconds later. (note: at the photo must be the hint "stegosaurus attacking a jeep").
Good luck with this