Question

White perch is a fish that is native to Atlantic coastal regions and is invasive to the Great Lakes. It feeds on native species and is thought to be the cause of the decline of the Great Lakes walleye fish populations. What was most likely its mode of introduction?
produce brought from the eastern states
trapped in a ship's ballast or a water tank
trapped in a cargo crate carrying nonperishable items
luggage brought in an overseas flight

Answer 1

Trapped in a ship's ballast or a water tank.

Ships take on ballast water in coastal areas (carrying small fish, larvae, or eggs) and release it in other ports, a common pathway for aquatic invasive species like white perch.