The Ant, the Plant, and the Caterpillar
“Hurry Lucida,” the ant pushed the growing caterpillar down the plant. “We must get you back down underground in our nest,” shouted Nathan the ant, “it’s not safe; there are too many predators tonight.”
The Ant, the Plant, and the Caterpillar tells the tale of a very special dependent relationship between Lucida the caterpillar, Nathan the Notoncus ant, and the Sweet Bursaria plant [a symbiotic relationship].
It follows the journey of a protective ant and a pudgy little caterpillar as they form a great friendship while the caterpillar grows to become the delicate little Eltham Copper Butterfly.
The Eltham Copper Butterfly is an endangered insect species found only in small isolated locations in Victoria, Australia. Like many endangered species, it relies on us to protect it and its habitat. Without our efforts to conserve it, in a flutter, it could be gone … forever.
MORE ABOUT THE BUTTERFLY
Eltham Copper Butterflies (ECB) is a small attractive butterfly found only in Victoria, Australia. It has bright copper colouring on the tops of its wings and can only be seen during summer months when it is an adult. The rest of the year, it lives predominantly underground, coming out only at night escorted by ants to feed exclusively on Sweet Bursaria leaves. The Eltham Copper Butterfly is a member of the Blue Butterfly family (Lycaenidae), 79% of which have a symbiotic relationship with an ant. It is a completely dependent (obligate) three-way relationship with two Notoncus ant species and Sweet Bursaria plants (Bursaria spinosa).
The larvae feed exclusively on the Sweet Bursaria plant. The adult ECB lay their eggs on or at the base of Sweet Bursaria plants that host a Notoncus ant colony. Notoncus ants are nocturnal ants that live underground in nests, including at the base of Sweet Bursaria plants. Once hatched, the larvae are guided by Notoncus ants into the ant nest, where they are tended to and guarded. This amazing service is achieved through a mixture of trickery and treats. Trickery in that the larvae of this family of Blue Butterflies are believed to give off chemicals and make sounds that can pacify ant aggression, mimic ant brood hormones, and attract and alert ants if the ECB larvae are alarmed. Treats in that the ants feed from sugary secretions, which are produced from ECB larvae in proportion to how many ants they need to guard them.
These nocturnal ants then lead the larvae out at night to browse on the Sweet Bursaria leaves and defend them from the many nocturnal predators and parasites that see them as a juicy snack. ECB larvae overwinter in the ant nest and are left to graze at night. Larvae pupate in or near the ant nest, with adult butterflies emerging from October to March each year, peaking from November to January. The adults feed on the nectar of flowers, especially Sweet Bursaria flowers, before they lay their eggs at the base of the plant, and the cycle begins again.
The Eltham Copper Butterfly is now endangered because of the loss of bush habitat. This is due to urbanisation, weed invasion, rubbish dumping, trampling on the plants, slashing and clearing of plants and wildfires. Agriculture has also caused the loss of the butterfly habitat. Any loss of species impacts the balance between nature and biodiversity.
To learn more: butterflies.net.au and swifft.net.au
