Dolphins

Threatened status:

  • All dolphins are a protected species in Australian waters. Some of our dolphins (eg: bottlenose dolphins) are relatively common but other dolphins are unique to Australia and vulnerable to extinction, such as our snubfin dolphin and Australian humpback dolphin.

Location:

  • Dolphins are found throughout Australia’s oceans in our offshore waters, bays and coastal inlets.

Dolphins are playful, intelligent, social animals that live in groups of up to 15 or more.

They play together and work with each other to catch fish and raise their young. Dolphins have developed a remarkable sense of echolocation which they use to communicate and sense the ocean around them, such as sea floor topography, obstacles and other animals. They produce clicks and sounds underwater by moving air between spaces or sinuses in their head.

The skin on a dolphin’s lower jaw is very sensitive, and is useful to investigate objects much the same way as people use our hands. Dolphins are mammals, which means they are warm blooded, air breathing and suckle their young.

15 species of dolphins and one species of porpoise live in Australian waters. They are all protected under the Environment Protection & Biodiversity Conservation Act.

Threats to Dolphins

The biggest threats to dolphins include plastic pollution, industrial coastal development, shark nets and commercial fishing such as gillnets and purse-seine nets.

These types of fishing nets are invisible to dolphins, which become entangled, trapped and drowned. Some dolphins follow fishing trawlers in an effort to catch food, and end up trapped in the trawl nets. Dolphins are also entangled and killed in shark control programs in Queensland and New South Wales.

Dolphins are listed as protected under the Environment Protection and Biodiversity Conservation Act 1999, which prohibits killing, capturing, injuring of interfering with dolphins in Australian waters. As a result of this Act, live dolphins that are incidentally captured due to fishing activity must be released immediately and such interactions must be documented. Dead dolphins must also be recorded in fishery logbooks.

It is increasingly reported that chemicals, plastic waste and bacterial pollution from sewage waste pose harm to Australia’s beloved dolphins.

 

References:

  1. http://www.iucnredlist.org/details/136315/0
  2. http://www.iucnredlist.org/details/82031667/0
  3. http://www.afma.gov.au/portfolio-item/dolphins/
  4. http://www.environment.gov.au/marine/marine-species/cetaceans/whales-dolphins-porpoises
  5. http://www.abc.net.au/news/2017-03-10/bottlenose-dolphins-threatened-by-contaminants-study-finds/8343000
  6. http://www.environment.gov.au/marine/marine-species/cetaceans/whales-dolphins-porpoises