Rocking the reds: Red admirals eclose

July 2026

Red admiral sunning itself on the last of the autumn leaves

I am rubbish at raising red admiral butterflies. There are other butterfly enthusiasts quietly raising hundreds of admirals as part of the Moth and Butterflies of New Zealand Trust (MBNZT) Red Admiral Project. I am celebrating that I have managed to raise a handful to adulthood. If you don't believe me, read last year's posts on raising reds.

I already had yellow admiral eggs on my nettles when I fostered some red admiral early instar caterpillars a few months ago. I only have two of the giant caterpillar castles that hold my big tubs of nettle, so I also filled my plant cage with nettles, which is designed to keep butterflies out, not in, and hoped for the best. The worst parasitic wasps are tiny and deadly and they take advantage of the smallest gap.

Admiral caterpillars eat A LOT so a big tub of nettle does not actually go far. In addition, admiral butterflies seem to be more generous with their egg laying than monarchs and it is every admiral caterpillar for itself. Obviously in the wild they would be thinned by a number of predators and I am aware that when I put eggs of any butterfly into captivity, I am increasing the number of genetically similar butterflies in an area.

Yellow admiral in the late afternoon sun

However, the red caterpillars and butterflies seem to cull themselves. Spiders' webs, drowning in standing water, flying directly at a hungry blackbird. The list goes on. I've also had the inevitable South African mantis trapped in the plant cage with them again and a native Cream-spotted Ichneumon wasp Echthromorpha intricatoria infected a few chrysalis. The latter is one of the natural predators for our native admirals - it is not a stinging wasp, but it does love admiral pupae for its young above all else. It has an important role keeping everything in balance, but unfortunately for the admirals, they have got more than their natural predators after them.

Cream-spotted Ichneumon wasp Echthromorpha intricatoria

The yellow admirals have had a higher success rate. I have three more admiral chrysalis in the plant cage awaiting a bit more sun, but otherwise my final tally for this season is 83 yellow admirals released and 52 reds, 10 of which were these late fostered ones.

I've now trimmed and fed my nettles with chicken and sheep pellets ready for next season. The Chatham Island X nettles are already responding with lush new growth, so the next admirals will have a good start.