Many people who walk through the Great Barrier Reef section of Sydney Aquarium have already heard of the symbiotic relationship the “Clownfish” has with the anemone.

The Clownfish picks off any small invertebrates as food that could potential harm the anemone and provides nutrients to the anemone by depositing fecal matter within the anemone. Any normal fish would most likely be stung, but the Clownfish is covered by a mucus membrane that the anemone does not recognize as food, it therefore provides a safe-haven for the Clownfish, protecting it from surrounding predators.

What we might not know is that all Clownfish are born as males, and can later change their sex to female. Generally a group of Clownfish will consist of a “harem”, one large reproductive female and one smaller reproductive male surrounded by even smaller non-reproductive males. If the female dies the reproductive male will change sex and become the female leaving the role of the reproductive, mature male to be taken up by the largest non-reproductive male in the group. A rather, unusual but very successful life strategy, that can be seen here at Sydney Aquarium.

So the answer to the question; Is Nemo a girl or a boy? It would most likely be that Nemo is a boy as he is a juvenile Percula Clownfish (Amphiprion percula). But he has the potential to join a small group of Percula Clownfish and take on the role as the girl or reproductive female.

If you were Nemo what would you do? Remain a boy or become a girl? Next time you make your way down to Sydney Aquarium have a look at our Tropical Marine displays that are home to a variety of different Clownfish, see if you can pick the female from the males.

🙂

The platypus (Ornithorhynchus anatinus) is a very unique animal found only in inland water bodies of eastern Australia.

It is one of three monotremes (egg-laying mammals), the other two being the long-beaked and short-beaked echidnas. With distinctive mammalian traits such as warm bloodedness, the habit of suckling its young with milk and the presence of fur, it also has reptilian traits such as laying eggs. Other interesting features of this amazing animal are its adaptations to its specialised mode of life; the duck-like bill, dorsal nostrils, paddle-like tail and webbed feet.

At Sydney Aquarium, we have 3 female platypus. Their names are Jackie, Nayda and Zoe. Each animal has its own unique behavioural traits. Jackie is recognised for her somersaults, Nayda lounges around inside the pots of plants and Zoe likes a good game of hide and seek. On the underside of their bill is their own unique pattern which stays with them for life, similar to that of a human finger print. These individual traits are all used as forms of identification for the aquarists who look after the animals every day.

The platypus are fed a variety of insect larvae, worms and crustaceans, eating up to a third of their body weight in a day. This would equate to approximately 20 kilos of food/day for an averaged size human. The animals are weighed once/week to monitor any changes in body condition. Handling allows for future veterinary procedures, if required. This ongoing conditioning results in a less stressed animal whenever any handling is required.

Platypus are notoriously secretive, which can make viewing of the platypus difficult in a captive situation. However it is important for all captive animals to have areas for foraging and hiding, similar to that of their natural environment. This assists in the balance of group dynamics by way of providing feeding and resting areas for each animal. Here at the aquarium, our girls have adapted well to their home and as a result can be viewed throughout the day, allowing people a sneak peak at one of Australia’s most secretive and unusual creatures.

Stay tuned for more blogs coming soon!