My idea is of a statue of a shark that when it comes into contact with blood it enters a feeding frenzy state that lasts for 10 minutes. When it enters the state, the statue will attack any organism that comes into a certain radius of it. If the organism gets away, the statue will pursue it until either the organism is dead or it's been 10 minutes since the start of the feeding frenzy state. If the statue is able to catch the organism, then the statue will kill it and the 10 minute countdown will start again. This cycle will continue until the statue is eventually unable to catch its prey within a 10 minute time span.
Idea is based on the photo below: