Feeling fly!

The Butterfly House at Melbourne Zoo is turning 40. Here, we chat with the Zoo’s invertebrates co-ordinator, Melvin Nathan, ahead of the birthday celebrations.

There’ll be flutters of excitement at Melbourne Zoo this December as its Butterfly House turns 40. The guest list is nothing short of spectacular, with the zoo hosting 400 to 600 butterflies at any one time. Originally proposed by Alfred Dunbavin Butcher, a former zoo director, the Butterfly House allows visitors to be immersed in a tropical wonderland – featuring meadow areas, understorey, overstorey and a central creek – that provides the habitat needs of the different species.

Invertebrates co-ordinator at Melbourne Zoo, Melvin Nathan — Image credit: Jo Howell

Melbourne Zoo's Butterfly House — Image credit: Zoos Victoria

To learn more about what goes on behind the scenes at the Butterfly House, we spoke with invertebrates co-ordinator Melvin Nathan.

Q. What does caring for the Butterfly House involve?

It’s quite an operation! We are one of the few zoos in the world that breeds butterflies, and we breed anywhere between 12 and 15 species at a time. We have host plants in the Butterfly House, each selected for a specific species to lay its eggs on. After about seven days the plant will be filled with eggs, and we transport that plant into a caterpillar rearing glasshouse where we hatch the eggs and feed the hungry caterpillars for about 3–5 weeks. After that, the caterpillars shed their skin and become chrysalises, where they undergo metamorphosis. This can take anywhere between 1–6 weeks depending on the species. We transfer the chrysalises into our Puparium to hang, and once they complete metamorphosis they emerge in the Butterfly House – and the life cycle continues.

Caterpillar in the Butterfly House — Image credit: Jo Howell

What’s it like working so closely with butterflies?

It’s incredibly enjoyable and rewarding. You can watch them grow up right before your eyes in such a short time. It makes you really appreciate the wonders of the animal kingdom – their mouthparts and diet change completely from eating plants to sipping nectar, and then they grow wings and fly!

Q. As the Butterfly House approaches its 40th year, how have you seen it evolve?

Over my time here at the zoo, I’ve been lucky enough to be part of several projects that have transformed the Butterfly House. One of the first was developing our Puparium. We replaced the old cupboard where pupae were displayed behind the scenes, with a purpose-built space inside the Butterfly House itself. It’s designed to provide the ideal climate and space for butterflies to safely emerge, and it allows visitors to learn about the butterfly life cycle and see which chrysalis turns into which butterfly.

Melvin Nathan checking on the chrysalis in the Puparium – image credit: Jo Howell

I was also part of the team that developed the golden-rayed blue butterfly interpretation area within the Butterfly House, which even displays the endangered species’ host plant.

But the biggest project so far has been this year’s major upgrade of the Butterfly House. We built a new waterfall that provides basking spots and mud-puddling areas for butterflies, expanded the bridge to 2.3m, and replaced the 40-year-old HVAC system with a brand-new one to help keep the temperature optimal so our butterflies can thrive.

Waterfall in the Butterfly House — Image credit: Zoos Victoria

Q. Do you have a favourite butterfly — and why that one in particular?

Yes, I do, the blue tiger (Tirumala hamata). We breed this species here at the zoo and the reason I like them is because of how resilient they are. They are quite tough and can fly long distances. In the wild, they go through an overwintering cycle where they gather in huge clusters on trees to survive the cooler months. They barely feed during this time. They are also a spectacular looking butterfly.

Blue tiger butterfly (Tirumala hamata) – image credit: iStock

Q. Can you explain the role butterflies play in the ecosystem?

They’re pollinators, just like bees, wasps, beetles, flies, mosquitoes, moths, and even some birds, rodents, and marsupials. These animals are the reason we have beautiful flowers and delicious fruits and vegetables. They’re also one of the foundations of the food chain, providing food for many other animals.

Q. How can we attract butterflies to our gardens?

Gardeners can plant nectar-rich flowers and native host plants that provide food, shelter, and breeding spaces for local wildlife. Avoiding pesticides and creating sunny, sheltered spots where butterflies can bask and rest also helps enormously. What’s great is that by attracting butterflies and other insects, you’re actually creating your own mini ecosystem. The presence of pollinators and native invertebrates brings in birds, lizards, and other wildlife, helping to establish a natural biocontrol cycle that keeps pest numbers in check.