The Red Admiral
Nigel Venters
Introduction
The Red Admiral Vanessa atalanta Family: Nymphalidae
The Red Admiral is potentially a wonderful release butterfly…and much more beautiful than the Painted Lady….The Red Admiral waits as a sleeping giant amongst possible release species….until the first brave release breeders appreciate the additional benefits this species can bring to their business. The Red Admiral is closely related to the Painted Lady butterfly (Vanessa cardui)…and so far breeders seem to have underestimated the Red Admiral's business potential!
A few points worth knowing about the Red Admiral:
- It is very easy to breed!
- There is no valid scientific reason why breeders cannot send Red Admiral livestock to any State within the USA.
- The Red Admiral is a migratory species. It migrates from the warm South each spring ….unlike the Monarch there is no hard evidence of a return journey in the autumn.
- The winter cold kills off nearly ALL the adults, if your climate has frost in the winter…then there is little chance of any wild overwintering adults surviving. Temperature experiments I have done with pupae…have proved that the idea (See Audubon Society: Field Guide to North American Butterflies) This species cannot overwinter as a pupae in a climate that experiences frost. Temperatures even close to freezing always kill the pupae…even though adults may survive.
- So no matter how many Red Admirals you release in any year….it makes no difference to your local population….it always relies on next year’s migrants to repopulate! (This fact is always avoided by the anti release body!)
- This same rule of thumb also applies to the Painted Lady! But I don't hear it used in defence of releases too often either!
So, next time you see a Red Admiral in your garden spare a thought that this beautiful creature will have flown many hundreds of miles to visit you! This magnificent butterfly is one of the world’s great travellers and you may see this anywhere in North America right up to Northern Canada. It also occurs in Mexico, Hawaii, Caribbean Islands and as far South as Guatemala. But this is only the North American story. The Red Admiral also occurs throughout Europe and Asia. Further to the East it is replaced by an almost identical (you’d have to look closely to see any difference!) Vanessa indica, the Indian Red Admiral.
Early European settlers in New Zealand missed seeing the Red Admirals each spring, and to remind them of home and so they took the trouble to establish Red Admirals in their new country. It is still found in New Zealand today where it competes with a smaller native species, the New Zealand Yellow Admiral (Vannessa lutea).
North American records show more records from the western side of the country but the fact remains that this wanderer could turn up anywhere! Unlike the Monarch, this butterfly’s migration north each spring is a one-way process and no southwards migration attempt has ever been observed in the autumn. The Red Admiral is really a sub-tropical species and although adults may try and overwinter in northern locations, most are killed by the winter’s cold. Observations and experiments in Europe show that winter survival is possible only when temperatures do not drop much below 25f (-4C) as an absolute minimum for a short period of time. Numbers fluctuate in the northern part of North America each year depending on how suitable the climatic conditions were in the southern part of it’s overwintering range, and also which direction the prevailing winds are at this time of year. Once it has made it’s journey north it soon settles into a continuos breeding cycle until any larva caught out too late in the year are killed by frost, and only then do the remaining adults try and overwinter. Often the “red” stripe to it’s forewing seems more orangey-red in USA. A deep crimson-red colour is the prevalent color in it’s European range.
Breeding
The Red Admiral is continuously brooded and easy to breed. If you catch a wild female put her into good-sized cage with some Nettles. The female will almost certainly have mated by the time you caught her so do not bother to try and capture a male to add to the cage. You will need to add some larval foodplants from the nettle family (Urticacea). Make sure you provide some shade from direct sunlight and spray the cage regularly with water.
Larval Foodplants
Position these so that the tops of the foodplant are touching the top of the cage. Examples are: stinging nettle (Urtica dioica), wild nettle (U. gracilis), false nettle (Boehmeria cylindrica), Pellitory-of-the-wall (Parietaria judaica also known as P. diffusa). Some books state hops (Humulus species) but I have never found this foodplant to be accepted.
Nectar Plants
The Red Admiral enjoys a wide range of nectar plants. In the spring it especially enjoys feeding on blossom from plum or apple trees. As the season progresses it continually adapts to what ever food is available, enjoying a range of nectar plants but also very keen on fermenting fruit and sap oozing from trees that have been damaged by boring beetle larva. Only the males only will visit animal droppings and even dead animal carcasses. In captivity they love fermenting banana and this is the best food you can give to your captive butterflies.
Ova
The pale green ova will be laid singly on the upper surface of the foodplant, but do watch for ova laid on the netting within the cage. Surprisingly if you leave these eggs, and you don’t expose the cage to full sun, most will hatch and find their way back onto the foodplant by themselves. The eggs usually hatch after about a week, sooner in warmer temperatures.
Larva
When it hatches, the tiny larva immediately spins a small tent out of silk around a tender young leave that it draws together. Over the next three or four weeks it spins more tents of increasing size using a number of leaves. These “places of security” as the sixteenth century English author Moses Harris called them, are very easy to find, as they are often high up on the foodplant. When almost fully grown it abandons its nest and then crawls up to the top of its foodplant and bites it’s way almost through the stem until it collapses on itself. It spins this together and the broken leaf becomes withered and dry, inside the larva finishes off the tender leaves and then pupates. Very occasionally it leaves its larval nest and pupates hanging from the underside a leaf. In the wild many of these lovely butterflies are stung by parasites through the silk of their tents. The final instar larva has two colour forms, black with a yellow horizontal stripe and yellow/amber with a white horizontal stripe; this in no way affects the wing colors of the adult butterfly.
Pupa
The pupa is varied in colour from a lovely pearl color with a “bloom like a plumb” to a dirty brown colour. There are some small metallic golden coloured spots on the abdomen section. It takes about 14 to 21 days to hatch depending on the temperature.
Adults
The adults pair easily in the pairing cage, but do remember to keep them well fed and watered. This butterfly does not like extremely hot dry conditions so mist often when this occurs.
Overwintering
The Red Admiral is a continuously-brooded species that does not fully hibernate. It is able to overwinter as an adult when the temperatures don’t fall below freezing too often. Try and overwinter adults in the fridge. Use a netted plastic sealed box (no airholes) and wake them up every month or so and give them a feed. You can wake them, warm them, feed them and return to the fridge within a few hours. As they are not really true hibernators, you will lose some adults whatever you do, but remember do not try and overwinter the adults too early in the season. You need to wait for the first cool weather of autumn to start before cooling them down in the fridge for the winter.
As a Release Butterfly
The Red Admiral is a powerful and sturdy butterfly that is well able to withstand transportation and release. It flies even more readily than the Painted Lady (Vanessa cardui) when released from boxes for weddings and other events.
Nigel Venters
