Attack dogs
Having toured an airforce installment, I know attack dogs are terrifying. They were behind metal gates and on detecting unfamiliar scent, immediately threw themselves against it. Repeatedly. Probably painful although it didn't slow them down even remotely. Without locking their dogs behind gates the military would have serious problems anytime new recruits arrived.
The point? When someone produces a film mainly about vicious dogs, featuring dogs as big procrastinators as these it's pretty hard taking such a film seriously. Given how quickly these dogs detected intruders on their island it's unbelievable they waited a day before attacking. It's also unbelievable that one of the opening victims survived hours (as least) even with pseudo-rabid canines chasing him, especially since they'd already caught him at least once.