We have some new residents in the Tūhura Otago Community Trust Science Centre – fitting with the theme of our Tropical Forest, we are now home to some tropical fish!
In our aquarium we have two species of tetras – the serpae tetra (Hyphessobrycon eques), and the aptly named black phantom tetra (Hyphessobrycon megalopterus). Originally from the Amazon River in Brazil and Bolivia, these two species are closely related and if you’re lucky, you might even catch them schooling together.
Schooling is the term used for when fish are swimming together in a coordinated manner in the same direction, whereas shoaling refers to fish that stay together in a loose grouping for social reasons. These behaviours are particularly important for fish in the wild, providing benefits such as predator avoidance, improved foraging success and higher chances of finding a mate.
Video: Tetras and a dwarf gourami swimming in the aquarium in the Tūhura Otago Community Trust Science Centre. By Sophie Adams © Otago Museum.
Joining our tetras in the aquarium is a species of gourami, specifically the dwarf gourami (Trichogaster lalius). Otago kids from the 1990s might remember Eric, our giant gourami (Osphronemus goramy), a relative of our dwarf gourami, but much bigger! Native to south Asia, these fish have some interesting adaptations that allow them to survive in shallow, murky, oxygen-poor water. Their pelvic fins are modified to act as feelers, which they use to navigate through their surroundings and find food.
Unlike most fish, gourami have the ability to breathe air with their labyrinth organ, which is an extension of the bones that hold their gills in place. Small blood vessels in this organ take oxygen from the air in a similar manner to how our lungs work. This allows them to survive in environments where there is very little oxygen in the water.
Next time you visit Tūhura, come and check out our new fish which are located in the biozone area, opposite the microscopes. Keep an eye out for any interesting behaviour, such as schooling tetras or our gourami breathing air from the surface of the water!
The Tūhura Otago Community Trust Science Centre is open from 10am to 5pm daily, admission charges apply.
Top image: Tetras swimming in the aquarium in Tūhura. By Sophie Adams © Otago Museum.