Mutualism: Painted turtle’s remove algae and leeches from snapping turtles. The leeches and algae provide the painted turtle with food while also helping the snapping turtle by getting rid of it’s parasite's. Parasitism: Nematodes are common parasites of painted turtle’s. They harm the painted turtle. These turtles are often found in large groups basking in the sun on a partially submerged log or rock. Basking is needed for survival for these turtles because they are cold-blooded and basking allows them to regulate body temperature. Also while basking the sun helps get rid of parasitic leeches. During the night these turtle rest at the bottom of a pond usually because they are diurnal meaning: active during day. Painted turtle’s also