NormTwigge

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  • in reply to: Develop an admiral habitat – is it worth it? #61665

    NormTwigge
    Participant

    Hi Rex, great to hear that you are focusing on a program to assist the native species of butterfly. Unfortunately there are several species of parasitoids in New Zealand that hammer our butterflies, many are introduced, either self introduced or introduced as biological controls,
    as P. puparum was to help combat the Cabbage white butterfly. Gathering pupae, as you have found, are often infected and introduces the parasitoids into a breeding environment. The best system is to collect late instar larvae and place them into a parasitoid proof cage or butterfly enclosure with hostplants to complete their cycle. Once emerged the butterflies can be released back to the area, or bred in a butterfly house.
    The MBNZT sells ‘castles’ or enclosures which are ideal for the containment stage, and late instar larvae on a potted nettle plant of even cut leaves in water will pupate readily.
    Also look at other species of native nettles, both the red admiral and yellow admiral butterflies will thrive on any Urtica species.
    Growing larger areas of nettles will also increase the larvae population, but also increase the parasitoid problem.
    The pupae can withstand freezing conditions, so are not at threat from hard frosts.
    All the best for the future, don’t hesitate to ask more questions.

    in reply to: Tachinid flies #61657

    NormTwigge
    Participant

    I am not aware of any reports of tachinid fly parasitism with New Zealand monarch butterflies. Certainly the chalcid wasp Pteromalus puparum is recorded as infecting them occasionally, but not to the extent of yellow admiral and red admiral butterflies.

    in reply to: Setting up a Butterfly House #61396

    NormTwigge
    Participant

    Hi Dragon21, your facility is well situated to source tussock ringlets, red admirals, yellow admirals, and other native butterflies. Be aware that a DOC permit is required to collect Forest ringlets unless you are lucky enough to find any outside of conservation areas, and any that may be bred from these are not permitted by MPI to be released back into the wild. The butterfly house needs an overhead irrigation system to provide regular watering for the hostplants such as Chionochloa, Urtica and other species which grow better in the ground rather than pots. Hanging baskets are notorious for drying out unless regularly watered. Nectar plants in pots can be rotated from a nursery area and into the house as they come into flower, and after flowering be dead headed, fertilized and put back into the nursery area to regenerate.

    Predators of many types are a threat to the stock, as are pathogens, both need to be watched for constantly. A good air flow through the house is necessary, and fine mesh lining is required to prevent predators from entering. At the Te Puna Quarry park butterfly house we have dispensed with artificial nectar as it ferments quickly in the summer, and unless cleaned regularly the dishes also develop mould, so a good supply of both potted and in-ground flower plants handle the requirements. Artificial nectar if fine if the facility is monitored on a daily basis.
    Hope this answers some of your questions, happy to answer any others.

    in reply to: Admirals in Northland #57907

    NormTwigge
    Participant

    Hi Terry,
    Since the introduction of the HWA into the Waikato area in 2015, the butterflies can be seen throughout the gorge, and have been observed at distances of at least 10 kms. in either direction, with reports of ovipositing at these points also, so the spread is slow. Biological controls never eliminate the target, as you know, and the Paper wasps are seen in large numbers around the honeysuckle, a real threat to their existence, as they are to all our NZ butterflies. A female butterfly is capable of producing about 200 eggs, so it would appear enough are getting through to build up numbers. Mind you, so do the wasps build up numbers with the increase in the food supply, so long term its anyone’s guess as to the reduction of the honeysuckle.

    in reply to: Admirals in Northland #57906

    NormTwigge
    Participant

    Although the original release site, a farm in the Karangahake gorge, was kept confidential, the Honshu White admiral can be observed throughout the various trails around the gorge. Now that the breed is established, Landcare research, who introduced the species, has no objection to anyone transferring eggs/larvae to another area that has honeysuckle in order to help control the weed.
    The life cycle takes about 8 weeks. One week for the egg to hatch, 6 weeks for the larval stage, and another week for the pupae to mature.
    Further information on the history of the release can found by googling Landcare Research NZ and Honshu White Admiral.

    in reply to: Admirals in Northland #57881

    NormTwigge
    Participant

    The colony of Honshu White Admirals in the Waikato have consolidated and are spreading their range in both directions from the gorge. Paper wasps are taking their toll of the larvae, but the butterflies seem to be slowly increasing in numbers. As long as roading contractors refrain from spraying the Japanese honeysuckle, which has happened in the past, the HWA’s future looks good.

    in reply to: Admirals in Northland #57832

    NormTwigge
    Participant

    As with the majority of the worlds animal species which are in decline, and even extinction due to human habitation, New Zealand butterflies also are threatened with various problems. Given that a butterfly can find its preferred foodplant on which to oviposit, the egg then becomes food for ants and other insects. Upon emerging, the hatchling then becomes food for ants, spiders, praying mantids, etc. and when larger, the caterpillars (particularly admirals) also run the gauntlet of birds, wasps, parasitoids, and of course the praying mantis. Wasps, mantids, parasitoids and even hedgehogs will consume the pupae, so there is a large mortality rate even before the butterfly stage is reached. Disease in large communities of larvae can take a toll, and scientists estimate that with butterfly species generally, less than 5% of eggs reach the adult butterfly stage.

    Drought periods impact on nettle species in the wild, but with a little care various nettle species can be grown at home. Seeds of Urtica ferox, the tree nettle, are obtainable from NZ Seeds, and Urtica dioica, although classed as a weed and is banned in a few districts in New Zealand, is the one I use successfully. Although nettle was once found growing around the outskirts of parks and reserves, which resulted in urban appearances of the Red admiral, it is now rare to find it, but can occasionally be found on back country farms that have been neglected, particularly around water troughs or under shelter belts of trees where stock shelter, as the plants love nitrogen.

    Reproduction of the plant is from the rhizome, which can grow up to 1.5 m. in a season and send up new growth along the length, or from seed.

    The Red admiral is a forest butterfly, occasionally appearing in gardens seeking nectar plants and hostplants, whereas the Yellow admiral is more an urban or garden species, the numbers of which are thought to be boosted by Australian migrants windborne across the Tasman. Like Monarchs, some form of protection is needed both for the plants and the caterpillars. Nettles need a good feed of nitrogen occasionally, some shade, and moist soil to thrive. Covering the plants with curtaining or mosquito netting also protects the caterpillars, or even better containment such as a castle. Like pets, a little care is required for best results.

    Research has been carried out on the NZ Red admiral:

    https://researcharchive.lincoln.ac.nz/handle/10182/1763

    Further information on parasitic wasps in relation to the admirals can be sourced by googling – Echthromorpha intricatoria – and Pteromalus puparum.

    in reply to: Beetle to control the weed moth plant #56098

    NormTwigge
    Participant

    Out of all the milkweed species I would be surprised if the Moth plant was the only one the beetle targeted.

    in reply to: Black Death #55965

    NormTwigge
    Participant

    Milton has been used for years by international butterfly breeders for viral and bacterial control, and sterilising both plants and equipment. Used at full strength ( 1 tablet per 2 litres water) for sterilising equipment and also plants, it has the advantage of not being corrosive like chlorine. At half strength it can be used to spray both plants and caterpillars. But bear in mind that while this will sanitise the plant leaves, it will not cure the disease that any larvae already have, and can still pass on the disease, and once infected there is no cure.

    in reply to: Forest Ringlet and Honshu White Admiral #55032

    NormTwigge
    Participant

    Hi Terry, the Honshu White Admiral has settled in to the Waikato area where it was first released, and although it does not appear to have spread out much, possibly owing to the vast amount of Japanese Honeysuckle in the area, it appears to have consolidated its stronghold. The species was released on Waiheke Island but failed to consolidate, and a second release was made. The Wellington area has been marked for a release, and others areas following.

    How successful they will prove to be as a control for the honeysuckle is yet to be established, when one looks back at the Cinnabar moth introduced into New Zealand in the early 1930’s as a biological control for ragwort, which is still prevalent here, or Pteromalus puparum and Apantales (now Cotesia) glomeratus wasps also introduced in the 1930’s to try and reduce the Cabbage White butterfly numbers. We still have large numbers of the white butterfly, but unfortunately both species of wasp have gone on to infect some of our endemic lepidoptera. However the authorities have said that biological controls may help rather than eradicate.

    The Forest Ringlet is still a subject of differing opinions, and while the Dept. of Conservation classifies the species as “serious decline”, in the past 18 months there have been numerous sightings in areas never before reported, Little Barrier Island being one. Volunteer workers on the Island had seen them over the previous few years without realising what they were, and only when someone recognised the species did it become news. As more and more people, and particularly trampers, become familiar with the appearance of the species, the more sightings are recorded. Steve Wheatley, the British conservationist who headed the recent update on research data of the Forest Ringlet, concluded in his Review document that there was insufficient statistical evidence to determine stability either way. My interest is still paramount, with Ruapehu forays being a learning experience, and now continuing in two areas with confirmed sightings within one and a half hours drive from my home.

    in reply to: Transferring eggs and caterpillars to new milkweed plants #55011

    NormTwigge
    Participant

    Easiest way for eggs is to lay the leaf containing the egg onto a secure spot on the plant, or use a pin to attach the piece of leaf onto a plant leaf, preferably near the top of the plant. When the caterpillar hatches it will transfer itself to its own preferred position. With small caterpillars an artist brush can be used to pick up and transfer them, but I prefer to let them transfer themselves by placing the leaf/branch they are on directly onto a fresh plant. The problem with transferring them with a brush is that if the caterpillar is in the process of moulting, moving them at that stage will probably kill them. Only if they are feeding or moving is it safe to do so.

    Handling caterpillars is not recommended as it is possible to transfer contaminants and bacteria to them. which can be fatal.

    in reply to: What is this Red-Orange Thin Waspy Insect #54997

    NormTwigge
    Participant

    It is almost impossible to identify an insect based on a brief description, so if possible the best way is to take a photograph, include it with the post to the forum, and it will usually be identified by someone. Most people these days carry a cell phone, so a photo should not be too difficult. The correct ID saves people killing off a native insect that may or may not be threatening a non-native such as a monarch caterpillar. Our native praying mantis appears to be on the decline, being displaced by the South African mantis. While I will quickly dispose of a S.A. mantis in my butterfly house or on a swan plant, I prefer to relocate the native variety, for while they may consume the odd monarch caterpillar, they also help to eradicate other pests such as flies, wasps, White butterfly caterpillars etc.

    The “Red-Orange Thin Waspy insect” may possibly have been a golden hunter wasp, which paralyses spiders and places them on its eggs in cells, ready to provide fresh food for the soon to hatch grubs. So they are not a threat to caterpillars. A quotation from a scientist is worth considering – ” Who gives a person the right to decide what animal lives and what dies”.

    in reply to: How to recognize species? #52529

    NormTwigge
    Participant

    Hi all, if you see an unusual butterfly in your garden, do your best to get a photo of it with your cell phone or camera, and send it to the website. Then it can be identified by us. Descriptions sent in from a previously sighted butterfly can often be misleading if it relies on memory.

    in reply to: Monarch caterpillars #52440

    NormTwigge
    Participant

    If the green caterpillars are eating the flowers, they are a species of moth caterpillar which only browse on the flowers, and not the leaves.
    The disappearance of the smaller monarch caterpillars sounds very much like a paper wasp problem. If the caterpillars are very small, as in 1st instar size, it could also be ants taking them.


    NormTwigge
    Participant

    Many species of caterpillar are reluctant to change diet after establishing feeding habits, but it is worth a try. If you are transferring to Ragwort, I would suggest using a young plant rather than mature one, as it could depend on which way the transfer is.
    Good luck, and keep us informed as to the outcome.

    in reply to: Urtica australis flower/seed/pollination #51594

    NormTwigge
    Participant

    Urtica australis is monoecious as you say, meaning the plant bears both male and female flowers. Pollination is primarily by the wind, or air flow, so don’t sleeve the plant yet, and leave it in an airy place. It will be reasonably obvious when the seeds set, they will be a brownish coloured seed as opposed to the flowers. At that stage it can be sleeved if desired, but I used to just cut of the seeding stem just before the seed was ripe, and place in a jar to finally ripen.

    in reply to: Caterpillars vomiting red and dying #50759

    NormTwigge
    Participant

    The colour of the vomit may vary with different chemicals. The plants may have been exposed to overspray, and if it was a systemic spray, which is absorbed into the plant, no amount of washing will remove the toxicity.

    in reply to: Terry's Admiral Project in Britain update? #50757

    NormTwigge
    Participant

    Hi Terry, regarding the lantana bushes, they will propagate easily from cuttings and only take about 6 weeks to form a root system. Much quicker than waiting for seed, I do it often to keep up a supply of nectar plants.

    in reply to: Wellington Overwintering Sites #50756

    NormTwigge
    Participant

    The butterflies may have congregated on another tree. I have observed a macrocarpa tree overwintering monarchs for several years, until one year there were only a handful. But half a kilometre away, where I had not observed any before, was a good number overwintering. While an tree may overwinter monarchs for many years, there is no guarantee they will keep returning permanently to the same tree.

    in reply to: over wintering chrysalids #50511

    NormTwigge
    Participant

    Monarchs only overwinter as adults, not as chrysalides, so your best bet would be to keep them in warm, bright conditions inside, and when they emerge condition them to outside conditions and then release them.

    in reply to: Oe (Ophryocystis elektroscirrha) #50212

    NormTwigge
    Participant

    As Jacqui points out, Oe is a natural occurrence in monarchs, and indications are that it co-evolved with the monarchs.

    “OE infects monarchs in all three North American populations. The eastern migratory monarchs have the lowest infection rate. Less than 8% of these butterflies are heavily infected with OE. More monarchs have OE west of the Rocky Mountains. About 30% of the western migratory population is heavily infected with OE. The highest rate of OE in North America occurs in the nonmigratory monarchs of South Florida. More than 70% of these monarchs have OE infections. The infection rates for monarch populations in North America have been constant for many decades”. (source University of Georgia)

    In Southern Florida, where the monarchs are nonmigratory, the milkweeds grow all year round, so perhaps this is a reason for the high infection rate. So does it follow that monarchs in the frost free north of New Zealand have greater Oe problems than those in the south?
    “How come Oe isn’t a significant problem here? I have never seen any major outbreaks of Oe.”
    Looking back on various postings on the forum would suggest that maybe it is problem, albeit a minor one, given that being a much smaller country than U.S.A, we have proportionately less monarchs.
    Food for thought.

    in reply to: Caterpillar with 3 lots of antennae #50019

    NormTwigge
    Participant

    Monarch caterpillars with more than the 4 antennae are usually genetic mutations, as are caterpillars that are sometimes the “wrong” combination of colours. Several years ago a member posted photographs of several monarch caterpillars they had reared which had a variety of multiple antennae similar to this one posted.
    Isolate the caterpillar and rear it through to adult, it would be interesting to see if the adult butterfly differs from normal.

    in reply to: What are these flys that kill my chrysalis? #49981

    NormTwigge
    Participant

    Hi MistySpills, Your photos were forwarded to me, but are a little hard to see for positive ID. But together with your description, I would be reasonably sure they are
    the Chalcid wasp Pteromalus puparum, which you can google to check. If they were on the “J” caterpillars and the newly formed chrysalis, it would verify them. The wasp will wait on or near a “J” caterpillar until it sheds its skin, and while the chrysalis is nice and soft the wasp will inject eggs into it. A female wasp is capable of injecting 100 plus eggs, and 120 wasps have been recorded emerging from one chrysalis , but once the pupal case hardens it is safe from the wasp. If your chrysalides have not produced a butterfly after a good two weeks, and are appearing an odd colour, it’s a sign they could be infected. The wasp grubs residing inside can withstand freezing temperatures for several days, so seal the chrysalis in a plastic bag and dispose of it rather than freeze them, as once the adult wasps emerge they will immediately mate and look for more prey.

    in reply to: nettles #49081

    NormTwigge
    Participant

    Hi Barry, if the admirals have settled on your nettles it would be a fair bet they have left eggs, but difficult to see. Much smaller than monarch eggs, and green. If you use a magnifying glass you may spot them, sometimes on a stinging hair or on the underside of the leaf. Once the eggs hatch the tiny larvae are at the mercy of hungry ants, praying mantids, wasps, and when larger the birds love them also.

    in reply to: WASP and Yellow Admiral #48903

    NormTwigge
    Participant

    The most humane way to dispose of any insect is the quickest way. My method is to place said insect on a flat surface and quickly bring another flat surface against it with force. Death is instantaneous. It may seem crude or cruel to some, but how can it be cruel if it is quick. I have never used the freezing method, as there is no proof the insect does not suffer, even briefly. However my method is possibly not for the faint hearted.

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