Whales - the Mysticetes (baleen whales) are believed to have diverged from the Archaeoceti during the late Eocene, about 25-35 MYA. Baleen whales possess plates which are of the
structure of hair which are used to sieve prey from the water during feeding and also have a paired blowhole instead of the single blowhole of the Odontocetes (toothed whales or
dolphins). Baleen whales are divided into four families containing right whales (Balaenidae), pygmy right whales (Neobalaenidae), gray whales (Eschirichtidae) and rorquals
(Balaenopteridae). All rorquals including the humpback whale have up to 100 throat grooves or pleats that reach from underneath the lower jaw to past the flippers. Mysticetes
represent the largest animals on earth. Their main food source is krill that occurs in large abundance in the polar regions. For breeding and feeding baleen whales travel large
distances often far away from the coastlines. However, some species like the humpback whales use coastal waters for their migration, breeding and socializing. There are six baleen
whale species that could be seen off south-east Queensland waters, the humpback whales (, the blue whale (Balaenoptera musculus), southern right whales (Eubalaena australis, fin
whales (Balaenoptera physalus), antarctic minke whales (Balaenoptera bonaerensis), dwarf minke whales (Balaenoptera acutorostrata subspecies).
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Dolphins - the Odontocetes (toothed whales), a group that also diverged from the Archaeoceti about 25-35 MYA. Odontocetes are generally described having a single blowhole, a fatty
tissue lump (Melon) forming the forehead which is thought to be used in focusing sound in echolocation and an asymmetrical skull with the right side being more developed than the left
side. Odontocetes are comprised of eight families containing sperm whales, beaked whales, river dolphins, narwhal/beluga, the ‘true’ dolphins including killer whales pilot whales and
porpoises (Bannister 2008). Approximately 21 dolphin species are found along the coastline of Australia, all of which are protected under the Environmental Protection and Biodiversity
Conservation Act 1999.Coastal waters are utilised by dolphins in a variety of ways including foraging, protection from predators, resting, and social activities (Filby et al. 2013;
Watson-Capps & Mann 2005). There are seven species of dolphins in the Gold Coast area, the Indo-Pacific humpbacked dolphin (Sousa ), Indo-Pacific bottlenose dolphin (Tursiops
aduncus), offshore bottle-nose dolphin (Tursiops truncatus), pantropical spotted dolphin (Stenella attenuata), long-snouted spinner dolphin (Stenella longirostris), common dolphin
(Delphinis delphis), and the orca (Orcinus orca).
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