He is a marine biologist and the owner of a pet store near Lake Victoria. They bring a captured Piranha from the underground sea lake there to him. He identifies the piranha of the lake that has appeared as an extinct Piranha from another era and deduces the piranhas must have survived in the underground lake through cannibalism.
He then gives the extreme serious advice to evacuate all tourists from the lake on the spot since he also knows through the sheriff that there are hundreds out there who have been released by the tremors, which the sheriff follows.
Through the continued analysis of the piranha that was caught he realizes it is a baby piranha, like the rest of them and that the adult ones have still not been seen. He contacts the sheriff and informs her about it.