How To Keep Stick Insects

Most stick insects will be happy at a comfortable or warm room temperature. They should be kept in a cage with at least some ventilation, such as netting or perforated zinc, to allow movement of air. Some species are likely to die if they don't have adequate ventilation. By contrast, some easy species will thrive in a medium to large cage with virtually no ventilation, as long as they aren't too humid.

Stick insects need a cage at least twice as tall as the insect is long, this is because when they shed their skin they hang upside down and fall out of their old skin. Some of the very small species can therefore be kept in a cage only 20cm tall. The largest species will need a cage a metre or more tall!

Keep the foodplant in a jar filled with water to keep it fresh, you will need to stuff newspaper or tissue around the stems to prevent the young nymphs crawling into the water and drowning. Old mature leaves are preferred to young leaves, in fact very young leaves will probably not be eaten at all.

There are many species of stick insect, and they all have different foodplant requirements. Fortunately, many species browse on different foodplants, and they commonly transfer from their native foodplants to common British plants such as bramble, rose or privet. If you aren't sure what they feed on, try bramble, hypericum, rose, Eucalyptus gunnii, oak and fern. They will almost certainly feed on one of these. In winter, Holm Oak (Evergreen Oak), can be used as a substitute for deciduous oaks.

I keep stick insect eggs at room temperature on damp paper towel in sealed plastic boxes to prevent them drying out. Make sure that you don't leave them in the sun or they will be killed by the build-up of heat. They hatch in about 4 - 7 months, a few may take longer. You can use perlite, vermiculite, sand, tissue or similar instead of paper towel, but remember to keep them damp and don't let them dry out. They need to be slightly damp not wet. They can be kept slightly warmer than room temperature to speed up hatching, but remember that they will be more prone to drying out, which could kill them.

When they first hatch the nymphs can be very small and some species are very agile and good at escaping from any small holes in the cage. They should be kept humid and given a daily spray with water. Some species should not be sprayed, this will be mentioned in the species texts.

Humidity is required more when the insects are shedding their skin. If it is too dry, the insect may not be able to release from its old skin, and may be found stuck. It may also get stuck if it falls from its perch, and will be found at the bottom of the cage, half out of its skin. If this happens, spray it with water and place it hanging upside down on some netting or paper towel that it can grip onto, and keep it humid or regularly sprayed. With luck it may be able to continue shedding. Trying to 'help it out' of its old skin is not recommended, as stick insects are liable to drop off their legs in response to being handled roughly.

They shed their skins several times before they become adult. When adult, they will soon become ready to lay eggs. Some species are parthenogenetic, that is, the females do not need to mate for the eggs to hatch. However, unfertilised eggs will hatch into females only. Most species do have males and females though.

The eggs can be left at the bottom of the cage as long as they remain damp. If vermiculite is used at the bottom of the cage, it can be a good incubation material. However, it is probably best to remove the eggs and place them in plastic boxes to incubate them.

On the following pages are a number of species that I keep in cages in my garden shed in the UK. The shed is heated to room temperature during the colder months of the year.

Going away on holiday

One of the things that I like about stick insects is that in many cases you can go away on holiday for a week without having to find someone to look after them. By careful consideration of their needs, you can give them plenty of food and perhaps slight adjustments to their conditions to allow them to cope.

The day before I go away I refresh the foodplants and give them a good spray with water. Give them plenty of food, but take account of the fact that more leaves will mean they use up the water faster. If the water container runs dry, the leaves will be dead within a day. I use jam jars of various sizes to hold the water, when going away I may swap to a much bigger jar.

If they need lots of humidity, I put polythene over the cages to keep humidity up above what it would normally be. I would also make the cages a bit wetter than normal just before going away.

You will need to check on the requirements of the individual species, as some may prefer to be too dry than too wet. In these cases you may risk them not being able to shed their skins, but this may be better than dying of disease through excess humidity.

Unfortunately I find that Eucalyptus will not last more than 3 or 4 days in water, the leaves begin to dry out. With these, it is better to find someone to add some fresh leaves every 4 days or so. Also remember that Eucalyptus drinks vast amounts of water. You may be able to find alternative foodplants to Eucalyptus, for example some species will also eat oak or Holm oak in winter.

By contrast, species that feed on privet or laurel can be left for about two weeks if needs be, as long as you make sure the water container is big enough, and that there is enough food so that they won't run out.

If eggs are expected to hatch, I put a leaf of the foodplant in each plastic box. If you are not sure when they are going to hatch, put a leaf in just in case. In the humid environment of a plastic box, a leaf not in water will last fairly well, especially if the leaf stalk is sitting on the damp substrate.