A diamond-shaped bottom-dwelling ray species, the southern stingray is common in shallow temperate and tropical coastal waters in the Atlantic Ocean. The southern stingray burrows in sand and seagrass to dig up prey items, in turn stirring up sediments and other small animals. This ‘bioturbation’ not only frees up prey items for other species – feeding southern stingrays are often accompanied by small fish such as bar jacks – but also create microhabitats for small invertebrates, and oxygenate the seabed sediments. Because of their important, but often overlooked roles, benthic rays such as southern stingrays are often referred to as ‘ecosystem engineers.’

Bull shark
The bull shark is the most well-known of the shark species that can move easily between salt and freshwater habitats. Their freshwater tolerance puts the