“They’re not just mindless eating machines.” That’s what zoo aquarist Gary Stoops hopes guests will learn when they visit the zoo’s five new sharks and observe them swimming alongside the 2,000 pilchards that share their tank.
The Reef in the zoo’s renovated Australian Adventure is now home to four blacktip reef sharks and one zebra shark. Although sharks are predators, they don’t feed constantly (not even in the wild), and they’re generally disinterested in the pilchards that share their 50,000-gallon saltwater tank.
Pilchards are schooling fish, so to the sharks they appear as one large organism. While the sharks sometimes swim through the middle of the school, they usually swim around the large mass of pilchards while navigating the tank.
Stoops refers to the balance between sharks and pilchards as “equilibrium,” but states that the sharks may occasionally try to eat the weakest member of the school. However, aquarists and zoo keepers feed the sharks often, decreasing the likelihood of predatory encounters.
Zoo keeper Kevan Mensch helps feed and train the sharks. According to Mensch, “We’re using operant conditioning to train the sharks to eat at different ends of the tank, so they won’t compete for food.” Zoo keepers also measure and record the amount of food sharks eat to ensure that every animal is consuming enough to stay full.
To date, all three species of fish in the shark tank (blacktip reef shark, zebra shark, and pilchard) are coexisting peacefully. Stop by The Reef in the Australian Adventure to see them up-close!
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