Contents > Butterflies > Resident > Admirals > Yellow Admiral
Vanessa itea (was Bassaris itea)
Distribution & Status
Widespread Found nationwide where it has a supply of it's foodplants. It is known to be a migratory species, so the native population possibly has a boost with migrants from Australia. It has had a population drop off again despite the slight increase in the 1970's and 80's due to reduced numbers of Nettles (Urtica spp) and since the introduction of the parasites (Ichneumon's and the wasp Pteromalus Puparum) to control the White Butterfly. However, the majority are probably lost to the self-introduced Australian Wasp, Echthromorpha intricatoria. Not present in the Chatham Islands.
Scientific Classification More info
Australian Admiral (Aust)Description
A native butterfly that also occurs in Australia, Norfolk Island and Loyalty Island. The Maori name means Yellow Cloak. This is a long-lived butterfly with individuals known to live over a year. Has larger numbers in years when Painted Lady's are recorded in New Zealand as both species are strong migrants and vagrants. Also, there is no sub-species in it's range, which suggests that migration is common throughout the range. Attracting Yellow Admirals to your garden is fairly easy, just grow some nettles and plant a few nectar plants. They are the next easiest to raise after the Monarch, but beware, like Monarch larvae, they have big stomachs and will stripe a plant bare in days.Ovum In English
Usually laid in pairs or trios, but rarely singularly on the foodplant near the tip of the stem where the growth is fresh. Fairly often on the side of one of the stinging hairs and occasionally laid adjacent to the foodplant. Initially pale green, turning to green in colour and dome-shaped with 8 to 10 vertical ribs. Slightly longer in height then width. They hatch in about 8 to 10 days. There are reports that say the shell is eaten by the newly hatched larva for it's first meal and others that say the larva eats a small hole near the top so it can get out, but will leave the rest of the shell behind.Larvae In English
Upon hatching it's a pale grey, but changes to shades of brown, grey-green or yellow after a few days. They are known to change colour when moulting to provide better camouflage with their immediate environment and lighting conditions. It has a hairy head with pale lateral and dorsal stripes along the body which is covered in setae. The larvae live about 4-6 weeks in warmer months and way longer in winter. They have 5 instars. In the first instar it eats fresh tender leaves from underneath. Then from the second instar it lives individually in a silken tent which it makes by attaching silken strands to curl the leaf slightly which it is presently eating until there's not much of the leaf left, at which point it moves onto another leaf and repeats the process. The colour changing and leaf-curling is for camouflage and protection from the elements and predators. However to us human's and probably some other predators their 'tents' can be a give-away to their presence in the last 2 instars as they will chew part-way through the stem of the leaf to let it droop, before starting to eat the leaf from the tip. This is to stop the plant 'bleeding' sap and making feeding easier. They also are more likely to feed in the open in the last 2 instars. They generally eat the leaves of the foodplants only. Before pupating, they spend up to 2 days head-down in a 'J' position on a leaf with their anal prolegs attached to a silken pad. Grows up to 40mm when fully grown.
The Admiral caterpillars can be hard to tell apart, the two easiest ways in the field is that the Yellow Admiral has a broader pale patch of colour on abdominal segments 4 and 6 then the Red Admiral. The second being that Yellow Admirals are rarely recorded on Nettle Tree (Ongaonga) (Urtica ferox) in the wild, however they will feed on it in a captive environment. An expert can also notice that the ratios of the setae compared to their bases are different in each species. The Pupae are equally hard to tell apart, but the Yellow Admiral is generally stouter and darker then the Red Admiral.Pupa In English
Shades of grey, brown, grey-brown with the odd gold spot, they sometimes have a more golden yellow colouration, but this usually indicates the presence of the parasite Echthromorpha intricatoria. The variation in colouration provides camouflage with their immediate environment and lighting conditions. The shape is angular, with a roughened surface. They are approx 20mm in length. They are attached head down by cremaster to some nearby sheltered spot. Pupation lasts between 10-18 days in summer and 25+ in winter. The wing colours show through in the last couple of days before emerging.Imago In English
The imago has a 45-55mm wingspan. They have a broad yellow band on both sides of front wings. There is a Albino variation that has white bands and paler brown on the remaining parts of the wings. They have a strong and darting flight that sometimes can be direct, however it is not as strong as the Red Admiral. It is a sun worshipper and will align itself with the sun preferring to rest in a head-down position with wings open. It is often encountered sunbathing on walls, rocks, fences etc and can be seen feeding on sap from tree bark, berries, fruit juices, nectar plants like Buddleia and Hebe with Red Admirals. Over winter, Yellow Admirals go into a quiescence, so can be seen on warm winter days on winter flowers. Come spring they are not as common as Red Admirals due to half the population surviving winter as larvae which appear as imagos in late October. If they feel threatened, they will slowly open and close its wings without changing position. Males are territorial and will investigate any other butterfly in the hope of it being a suitable female, especially in the late afternoon when there is more freshly emerged females flying.Habitat
A open country and garden butterfly that is seen in most types of habitat since it's foodplants grow in most habitats from the foothills to city gardens. Often seen sunning itself on rocks and paths, especially in the afternoon.Food Plants
It will feed on any of the Nettle species (Urtica spp), but prefers the softer leaved varieties like Small and Scrub Nettle (Urtica urens and Urtica incisa). It will eat the introduced Perennial Nettle (Urtica dioica). It has being recorded on New Zealand pellitory (Parietaria debilis), a stingless plant of the Nettle family.Lifecycle