There are thousands of species of stick (and leaf) insects in the world and they all come under the scientific heading PHASMIDA or phasmids in plain english.
Most come from the warm jungle areas of the world, some from the warm dry areas but few live in colder (& often wet) climates like northern Europe & Canada.
Whether you keep them as food for your reptile, mantid etc. or as your family pets, they have their own particular fascination for all, with their ability to blend into the brush and foliage being most prominent.
The stick insect, the brushwood insect, the leaf insect - they are all well adapted to survival. Some have wings, some have lost the ability to fly and some have even lost and then re-evolved their wings.
+ > Ova >= Hatch => Hatchling Nymphs >+
| | ^
| v |
| +>= Shed skin =>+ More Nymph Stages >+
| +> Adult >=Mates and/or Lays =>+
Ova "hatching" may take from as little as 6 weeks to many months. In a few species ova may take more than a year to hatch and some, which require low temperatures (near or at freezing point of water) to mature, may hatch from the same batch over many years. Most species take 2-5 months to hatch. If they don't hatch when you expect, or not all hatch at first, then don't throw them away too hastily, as some ova have a very large spread in hatching, even years apart.
Nymph "skin shedding" may take from 1 week to 3 months depending on the species and the stage (called "instar") they are at.
Adults usually mature within a week or two after the last skin change. And will normally mate readily if both males and females are present. You should be able to observe them mating, the male (smaller of the two) will climb on top of the female and their tails will link together. They will remain together like this for some hours or days.
In many species, fertilisation of the ova by a male is not necessary for the ova to develop and hatch. This is called parthenogen(et)ic reproduction and stick insects specialise in it. In some species, fertile males are rarely, if ever, seen.
Adults should survive at least a month and depending on the species for 4-8 months and some over a year. In some species (eg Phylliums), males will only survive long enough to mate but the female of these species will survive for months.
You will find a great number of methods suggested. Some work, some not so much. A lot depends on the species. The simplest good solution is to lay them on a bed (1-3cm, 0.5-1" deep is ideal) of washed & sterilised fine sand, in disposable plastic food trays or in a hatchery box. You can keep the sand just moist or very moist according to the species. You may like to drill a few 1.5mm holes in the lid for the drier species.
If you get mold it is an indicator that the species does not like the level of moisture you are giving them. Dry them off (leave the lid off), gently wipe away the mold, then place on fresh sand and lower the moisture level. Often it is only necessary to damp the sand in the corner of the container and not the ova themselves. Sometimes only one or two ova go moldy, invariably they were damaged, the solution is to keep them slightly drier. Frass (droppings) and stray vegetation will encourage mold, remove as neccessary.
This "sand box" method works much better than "kitchen paper towel" method, which tends to mold easily and dries out too fast. Spray periodically according to the species and the box seal. You may find that with some trays need no breather holes, because the lids fit more loosely. Cyclical damp and then dry periods of a few days is ideal for some species. A few species must never be allowed to dry.
Hatchlings may have their eggshell attached to them or their legs. Spray with water and after a minute or two crush the eggshell if they still don't pull free. Use a toothpick to carefully assist. Be careful, as some species will throw their legs if you pull on them.
Most species may require young/softer foodplant leaves (excepting perhaps Phylliums on bramble - use wild/miniature rose) and they may not always take the expected adult foodplant. So be prepared to go out to fetch the softer leaves and offer a selection of foodplants if necessary. Always seek advice if you run into problems.
Difficult to start feeding hatchlings will nearly always start feeding if they are in with adults or at least larger feedng nymphs of their own kind. Cutting/shredding leaves rarely substitutes for this. And be aware some species (even as nymphs) will attack another species nymphs (the first sign is missing legs/antennae - may also be a sign of overcrowding), so putting them in with another feeding species to get them to feed, may also bring its own hazards.
Shedding Nymph Skin
The skin is their exoskeleton and they are able to shed their skin best if they are moist, well fed and free from disease. Many, which fail to shed skins successfully, do so because they are too dry, were starved or got diseased.
If you have to, you may assist with your toothpick and water spray. Be careful and be aware that even if they lose part of a limb they may be able to regenerate them completely if they are young enough. It usually takes 2 or 3 skin changes to achieve this, but nothing will save a limbless nymph because starvation is inevitable.
Stick insects are normally herbivores.
Most will eat the leaves of Bramble (Blackberry), Rose, Oak, Hawthorn and Raspberry. Many will eat Ivy, Privet, Rhododendron, Eucalyptus and Hypericum. Some eat palms, grasses and more exotic houseplants, even lettuce.
Beware of shop bought plants as they often contain (systemic) insecticides which will kill your insects within a few days or weeks.
Cut watered foodplant is a common feeding method. Just remember to block the small nymphs from drowning in the water. Kitchen towel wrapped round the foodplant stems, wetted and jammed into the top of a bottle of water is ideal. You could try watered oasis/sand in a jar/cup. Whatever method you use, they will all need more frequent topping up with water in the summer time.
Mating and ova laying
Generally, there are no special requirments for mating, but some will not mate unless they have the correct conditions for laying the ova (eggs).
Whilst some lay their ova anywhere on foodplant stems and curling leaves or just drop them to the floor, others will only lay ova in deep/damp peat or sand, even your oasis.
Housing and Cages
You can purchase specially made net/glass/perspex cages/terrariums. A simple plastic fish tank with grilled lid will do for many species. For most species, cages should have a height of at least twice (better 3x) the length of the stick insect, when fully stretched out as it will need room to shed its skin and you will need to keep an eye on its growth and upgrade its cage as required, or start out with a cage height of 3x the given length of the adult stick insect. Those species which do not hang to shed their skin, will need unobstructed room on the floor of the cage of at least 2 times the body length of the insect, so that it can walk clear of the its old skin. Whatever you use, be aware that there is a great deal of variation of humidity and temperature required across the species range. But as previously stated, most are hot/warm jungle species.
Some keepers prefer using potted plants instead of watered foodplant, with automated heating, humidity regulation, spraying and breeze generation installed. Terrariums with synthetic plants, water feeders and bark/drift roots make a fine home and display for these wonderful creatures.
You will find nearly everything you need down your local reptile/aquaria pet shops.
On the cheaper low tech end, most species of stick insect do not need heated cages and are happy with watered foodplant.
A temperature of 18-23'C depending on species is fine. A usual domestic house temperature will often suffice provided extremes are avoided.
In some species more or less frequent spraying with water is advisible, though for many a correct air humidity and 24hr access to a wetted sponge/paper tissue is the best. Some species will die if sprayed but may still drink. Others may lose limbs due to rot or just die if too humid. Lack of humidity is indicated by bad skin shedding and a shrivelled appearance.
Generally, follow the habitat and weather patterns of the places where a particular species is found to be indigenous. On the whole, be a little cooler and a little drier with access to water on a sponge/paper tissue and they should be fine.
"Ghost like" phasmids, which are nocturnal jungle floor dwellers, will generally thrive in low-light, high humidty conditions with leaf litter (use kitchen towel if need be) or bark to hide under during the day.
Many species can be handled easily, without damage to themselves or their handler. But some give off chemical poisons/irritants/foul smelling fluids and others are positively nasty with many/huge spines and even large worrysome hooks on their feet.
If it worries you to pick them up, then its better you don't. For if you panic, then you could fatally damage your prize specimen. The same is particularly true for children. Even if you use a stick to perch them on, always remember, many of them can run very fast. If in doubt wear a leather glove.
Always keep other pets well away from them, unless they are the pet's food.
Treatment of Waste
Unless the stick insect is indigenous to the area you live then you should take some precautions not to accidently release the species into the wild in your locality. In most countries it is illegal to accidently or deliberately release non-indigenous insects in to the wild. Some basic precautions will ensure you comply.
Any possibly ova (egg)/nymph/adult containing material such as frass, peat, sand or plant material, should be treated to kill off any insects within.
1. For ova containing material either freeze, burn or microwave well. For the ova of some species, freezing may not work. So it is advisable to microwave/burn.
To microwave - place material in a disposable microwaveable food tray with the lid on. Heat it until (1-8 minutes depending on amount of material ad power of microwave) the material has boiled. 1 minutes at 1000watts for about 20gms of dryer frass material as a guide. After its been microwaved let it cool and then flush down the drain (preferred) or place in a composter.
Soaking overnight in undiluted strong bleach will kill stray ova. This can be used for containers/oasis/bark etc.
2. For nymph/adult containing plant material. Then its advisable to burn it. If this is not possible then polythene bag it and seal these bags. Then seal all the bags in a large bin bag for at least a month preferably two. Keep animals/humans away sop the bags remain sealed for the duration. Then dispose of the contents on a composter.
PSG Culture List
This is a list of Phasmid Study Group culture lists many species known to be/have been under culture. It lists just under 300 more commonly available species
For each species, it gives the PSG number, the name, the locale, sizes, foodplants and other useful information.
The list is available online, so do a search for "Phasmid Study Group", "PSG phasmid" and "Ed Baker" .