Adult blue marlin have few predators apart from killer whales, sharks, and humans. No dead whale sharks were found. Conservation Hall; Sea Cliffs; Sharks, Rays & Turtles; and Ocean Wonders&colon; Sharks. Elephant seals are prey for orcas and great white sharks. They display aggression towards sharks and smaller dolphin species. Whale carcasses comprise an important part of the diet of white sharks. Shortfin mako sharks travel long distances to seek prey or mates. The average size of adult whale sharks is estimated at and . It was one of the largest gatherings of whale sharks recorded. Marine life includes orcas and great white sharks. Many fish inhabited the Carboniferous seas; predominantly Elasmobranchs (sharks and their relatives). Hammerheads, the requiem sharks (such as the bull and blue sharks), and smoothhounds are viviparous. No DNA samples were found for large animals such as catfish, Greenland sharks, or plesiosaurs. Spiracles are reduced or missing in active pelagic sharks. Weights of particularly large female tiger sharks can exceed .