Three young shark taggers run into dangers ranging from poachers to large reptiles while exploring Florida's western coast. Checking out the mazes of mangroves and old shell mounds around Sanibel Island for wild oranges resistant to the citrus greening disease that is threatening the state's cultivated fruits quickly leads Cuban American tween sisters Maribel and Sabina and White Midwestern farm boy Luke into tense encounters with both a tremendous Florida saltwater crocodile tending her batch of hatchlings and a pair of drunken outsiders who turn out to be animal traffickers. Plainly not shy about recycling themes, plot elements, and character types from previous entries, the author also trots in another ghost, some more buried gold, and Capt. Pony, a cranky septuagenarian fishing guide who is accompanied for comic relief by an attack goose (named Carlos, after a former king of the area's Indigenous Calusa people) to supply the young naturalists with snippets of local history. The splashy, suspenseful, and occasionally supernatural climax ends properly with the baddies in the hands of the law and large numbers of captive croc hatchlings and baby turtles rescued. Capt. Pony (whose father came from Cuba) and the girls are repeatedly described as speaking Spanish but the text contains little actual Spanish, and Sabina is described as having "weird, witchy powers" due to her contact with santeras in Cuba. The wildlife and natural settings remain fresh; not so much the characters and plot. (Adventure. 9-12) Copyright (c) Kirkus Reviews, used with permission.