Welcome to my web page on the
Indian Walking Stick Insect
(Carausius morosus)
The perfect insect pet

I have found walking sticks to be facinating insects. They are colourful, easy to keep, and useful for teaching both students and the general public about insects, science, and nature.

I first put up this page back in September, 1997 and have had many people visit. Their comments and questions have inspired me in 2001 to improve and expand this page to serve a wider audience. These pages describe the information that I have obtained about the care and maintenance of my Walking Sticks over the last few years. Recently (2008), it is clear that this species has become a serious pest in Southern California and I have modified this site to advertise this concern. Please see the warnings below and don't let your pets escape in to the wild.

I have confined this site to one walking stick, the Indian Walking Stick Insect (Species: Carausius morosus) . There are many other species of walking sticks and information about them can be found at other sites listed in the "References" link.

Warning: Don't let these insects escape into the wild and cause ecological damage as a feral population. This is a real possibility with this species! Be careful and responsible. If you have them, DON'T let them escape! (See the warning section for more details.) As with any pet, always be responsible and if you keep them make sure that they don't escape.

Please use the links on the left to navigate through this site.

Since Sept 29 '97 you are visitor number .


Warning: Walking Sticks can escape and become ecological pests

The escape of this species into the wild has caused ecological problems in Southern California and Britain.

The Southern California problem

The presence of the Indian walking stick in the wild in Southern California, specifically San Diego, is a concrete example of the damage that can be done by feral walking stick insects. They have been in southern California since before 2001 and have been expanding their range over the years (see links below).

As an example, the Members of the Ocean Beach Community Garden, San Diego, have been having difficulty with feral walking stick insects and have asked me to post the following message:

WARNING • Stick Insects can also be Pests!  Just as with any Pet... it is very important that you are responsible for it so please read below.
Non-native Stick insects should never be released into the wild due to the risk that they could reproduce and cause damage to an ecosystem where they are not normally found - non native species are considered plant pests. This includes making sure any eggs are disposed of as well, by crushing, boiling, or burning, as no special care is needed for many species' eggs to hatch. If you are in the United States or Canada, tropical species such as the Indian Walking sticks are considered plant pest and a permit (United Stated Department of Agriculture or Canadian Food Inspection Agency) is required to import them (and be granted only to secure instutions. In other areas, check with the appropriate government agency about legality (e.g. a Department of Agriculture or similar agency)

This is a unfortunate example of the damage that can be done by feral walking stick insects. Here is a photo from the San Diego area that shows a number of walking sticks an the level of the infestation.

I count 44 insects; how many do you count?
(Photo taken by Judy Swink, San Diego, and obtained from Ruth Hoffman, Ocean Beach Community Gardens; used with permission. )
WalkingStickOnIvy Here is another example of the damage that can be done by feral walking stick insects. The photo was taken with a flash after 10 PM in early January, in an ivy bed adjacent to the front steps of a house. The insects clearly prefer the ivy over the neighboring bushes and lilies.

I count over 60 insects; how many do you count?
(Photo taken by Judy Swink, San Diego; used with permission. )

Also see the following links:


The Indian walking stick can also be found in the wild in Britain (http://www.uksafari.com/stickinsects.htm). Supposedly it is legal to keep them as a pet in Britain (http://www.petbugs.com/caresheets/C-morosus.html) and one can buy them from British pet suppliers (http://www.crafts-flowers.co.uk/page7.html). It has been claimed that they cannot overwinter in the British climate (http://phasmid-study-group.org/en/content/Naturalised-British-Stick-Insects-Malcolm-Lee) so they my not be as serious a feral pest as Southern California.


Walking Sticks are insects

Walking Sticks are insects. They have six legs and a chitin exoskeleton. They belong to the Order Orthoptera, which includes not only walking sticks, but also grasshoppers, katydids, crickets, praying mantids, and cockroaches. Walkingsticks belong to the Suborder Phasmatodea, Family Phasmatidea which includes both walkingsticks (which look like sticks) and leaf insects (which look like leaves). I will not deal with leaf insects here but they, too, are interesting insects.

There are several thousand speices of Walking Stick insects and many are kept as pets. The ones I had, and describe here, are Indian Stick Insects (Species: Carausius morosus; Pronounced: Ca-rau-si-us mor-o-sus). They are also called the Laboratory Stick Insect because they are easily kept in the laboratory for research experiments. They range in colour from a dark-brown (almost black) to bright green, with the younger stages usually being browner. Walking Sticks take several months (4-6) to grow from a first instar stage, which is about 1 cm long (1/2 inch), to an adult of about 10 cm (4 inches).




Walking stick insect can be the perfect pets *

Advantages of Walking Stick Pets:

  • They don't smell, which means that you can keep them anywhere in the house without worrying about "stinking-up-the-place" (eg. a child's bedroom).
  • They eat lettuce, which means that you don't have to grow exotic plants just to feed the insects.
  • They can't "infest" your house so you don't have to worry about any "escapees".
  • They teach children to care for life so they can be an ideal first pet for youngsters.
  • They have a life span of about one school year, which makes them ideal for a year-long school class project.
  • They have no wings so they can't fly and escape.
  • They walk relatively slowly and carefully, so they dont't scurry like roaches which tend to give "insecta-phobes" the "willies".
  • They can be handled easily by children without fear of being bitten or squishing them.
  • They don't need daily care. They can be left for several days (up to a week) without care (they don't need a baby-sitter for a weekend trip).
  • They can be used to teach children (and adults) the value of life.

 Dis-advantages of Walking Stick Pets:

  • They breed well if cared for properly.
  • Special Exotic Pet Permits are usually needed in most locations. In North America and probably most countries, these are usually only given for research or special purposes and not for general pet use.
  • * Warning: There can be devastating ecological results if these insects are released into the wild. See the warning above.


Care and Maintenance

The cage size should increase as the insects grow.

Your pets should be kept in a cage or container that is large enough for them to walk around and small enough that they will easily find the food you give them. As they grow up you will have to increase the size of the cage. You can start with a plastic cup (photo on the right) for the hatchlings, move up to a 500 ml jar for the younger stages but will have to move to a 2 litre or larger container for the adults, especially if you have more than one insect. These containers should have good ventilation to permit the insects to "breath" and also to reduce the humidity and thereby inhibit the formation of mold and fungus in the container. I put a layer of dry paper towel on the bottom of the container which allows the easy removal and clean up of the insect's "wastes".

Make sure the container has a stick or other place where the insects can climb up and hang down. They need to hang from such a place in order to shed their skin when they moult. They need to moult several times before becoming an adult.

It is also advantageous for the container to be clear plastic or glass so that you can easily see in and enjoy their activities.


I fed my insects Romaine lettuce (the green part not the white basal stalk) that has been washed under the kitchen tap. I remove any off-colour or damaged portions, too. The lettuce should be changed, along with the bottom paper, every 3-7 days, depending on the amount eaten and the presence of fungus.

They will also eat leaves from raspberries, privet, and many other related plants if given the chance. This is usually only possible during the summer when leaves are plentiful.


The adults can easily be picked up between finger and thumb. The younger instars may be damaged with clumsy handling so it is better to let them climb onto a piece of paper to examine or transfer them. They are nocturnal, meaning that they are most active at night, so you may want to keep their daily light-dark cycles such that they are active when you can observe them. During the day they are usually inactive and still unless they are disturbed.


Life cycle - Breeding, growth, and moulting.

Many walking sticks, including the Indian Walking Stick, are parthenogenetic. The population consists almost exclusively of females. These females are able to lay fertile eggs (without mating or the presence of males) which develop into more females, etc. Their eggs are oval in shape, dark brown, 2-3 mm long, and have a lighter-coloured knob at one end. When they hatch, this knob comes off and the walking stick climbs out. The eggs hatch after 10-12 weeks at room temperature. After they hatch, the egg shell often remains attached. It will fall off after a few days so there is no need to remove it by hand. Hatchlings are about 1 cm long (see photo on the right).

They grow by moulting (shedding of the cast skin. There are about five moults (I'm not sure of the exact number). Each moult allows the skin to increase in size. It is important to have one or more sticks in the cage so that the insects can use them to moult. The moulting process involves them crawling out of their old skin and this can best be done using gravity to help them out. They need somewhere that they can hang from while they moult. The absence of a stick or lid that they can hang from will severely hamper their ability to moult successfully. An unsuccessful moult will kill them.

When they reach adulthood the moulting stops and it remains the same size for several months (the adult lifetime). During adulthood the primary task is laying eggs. One female can lay several hundred eggs in her lifetime of several months.


Where can I get walking sticks?

Pet walking sticks are quite common in Europe, especially the U. K. (I guess it goes along with gardening.) There are several suppliers in England, but as far as I know they will not ship to North America. In any case, importing exotic pets is usually against custom regulations.

I am located in Alberta, Canada and these insects are officially not permitted to be kept with out a federal permit. I'm not sure about the situation in the USA, but the situation is likely similar.

I currently (Januuary '09) don't have any and have not had any for many,many years.

Please see the warning above.


Extra "Interesting Facts" about Carausius

This species of walking stick has been into space!

There are several instances where experiments in space have used walking sticks.

  1. Apollo 17 was the sixth and last Apollo mission to the lunar surface (December 1972).
    It contained Carausius morosus (stick insect) in the Biostack II Experiment set.
    • http://spaceprojects.arc.nasa.gov/Space_Projects/flylab/flight.hist.html
    • Bucker, H. 1974. Life Sci. Space Res. 12: 43-50.
  2. The Apollo-Soyuz mission in July 1975 conductied a series of science experiments.
    BIOSTACK III - Animal - Brine shrimp eggs (Artemia salina), Flour beetle eggs (Tribolium confusum), Grasshopper(??) eggs (Carausius morosus)
    • http://www.apollo-soyuz.net/
  3. In November 1985 the D1 Spacelab mission, using the Biorack, did experiments to examine the effect of cosmic radiation, background radiation and/or low gravity on stick insect eggs (Carausius morosus) at early stages of development.The experiments showed that the larvae from all eggs penetrated by heavy ions under microgravity had shorter life spans and an unusually high rate of deformities.
    (Principal Investigator: H. Buecker, Institute for Flight Medicine, DLR, Cologne, Germany)
    • http://spaceprojects.arc.nasa.gov/Space_Projects/flylab/flight.hist.html
  4. Space Shuttle January 22, 1992
    Flight Number : STS-42, Orbiter : ATLANTIS
    IML-1 Experiment BIORACK SYSTEM
    Expt# 10-D : Embryogenesis and organogenesis of Carausius morosus under Spaceflight conditions
    • http://www.nasda.go.jp/Home/Space_Utilz/e/iml-1_e.html
    • http://science.ksc.nasa.gov/shuttle/missions/sts-42/sts-42-press-kit.txt


Wigglesworth's The Priniciples of Insect Physiology. 6th Edition (1965)

The "facts" below have been taken from Wigglesworth's The Priniciples of Insect Physiology. 6th Edition (1965)(2). They are presented in the order in which they appear in the book. The page number is given along with the original reference in many cases.:

  • Supposedly temperature can be used to affect the sex of the insect. "...the eggs of Carausius (which are normally all female) if incubated at a high temperature show partialy male characters in the offspring: some parts male, some female, and some intermediate." (pp. 87)
    (From Bergerard, J. Biol. Exp. 246 (1958), 189-232 gynandromorphs in Carausius)
  • Like many insects, Carausius can regenerate lost appendages over the course of several moults. Unlike most insects they can purposefully detach an injured limb (called autotomy) at the level of the trochanter. There is a special muscle that breaks off the leg at a joint where there are no muscles running across that specific position. Then internal membranes wall off the break and the epidermis spreads to form a terminal scar and subsequently regeneration begins. (pp. 100-101)
    "Franken-stickie" - What is most original about Carausius is that supposedly it can be decapitated and upon replacement of the head, the epidermis (integument) and gut will grow together again and rejoin the head to the body. Unfortunately the nerve cord will not grow together again.
    (From Malabotti, A. Akand, Anz. Wein, No. 18 1934)
  • For the developmental genetics fans out there: there is homoeosis in Carausius. There is heteromorphous regeneration where the replacement of one lost appendage occurs with one that belongs to another region of the body. The example given is that of an amputated antenna regenerating as a fore limb. See figure #78 in Wigglesworth. (pp. 103)
    (From: Brecher, L. Arch. Mikr. Anat. u. Entww. Mech., 102 (1924) 549-72.)
  • The method of walking (e.g. which legs are used when) changes if one or more legs is lost. Typical there is a two step motion where the fore and rear of one side and the middle on the other side move foreward together; then the opposite move foreward in an alternating pattern. However, if the middle legs are lost then the pattern changes to a four step motion of right front, left rear, left front, right rear. (pp. 171).
  • The integument colour is influenced by neurohormone C1 which was extracted from the nervous system of Periplaneta (cockroach). (pp. 178)
    (From: Gersch, M. et al. Ber. u. d. Hundertjahrfeir d. dtsch. ent. Ges., 1956,146-69 ; Naturwiss., 20 (1957),525-32 ; J. Ins. Physiol., 2 (1958), 281-97 ; Z. Naturforsch., 15b (1960), 319-22 .)
  • Carausius is nocturnal.(pp. 205)
  • Carausius lack colour vision.(pp. 205)
    (From: Schlegtendal, A., Z. verg. Physiol. 20(1934), 545-81.)
  • Carausius shows a diurnal pattern of "thanatosis" or "death feigning" which comes on during daylight. This is the act of becoming volantarily immobilized appears similar to the state of "catalepsy" in man. The walkingsticks usually assume the position with all the legs and antennae fold together to form a stick. While in this state the legs can be moved and will retain their new position in a static or fixed way. Supposedly the legs can be moved into the appropriate way so as to balance it on its head. (A neat parlor trick?) See Fig. 197 on page 277.
    (pp. 277)
  • Carausius blood, which is called haemolymph, is only 1% protein. (pp. 382)
    (From: Florkin, M., Mém. Cour. Acad. Roy. Belg., 16.(1937), 69 pp.
  • The gut pH of Carausius is about 7.0-7.5, which is similar to many insects in being weakly alkaline. (pp.453)
    (From: Castelnuovo, G., Arch. Zool. Ital., 20.(1934), 443-66
  • It appears that Carausius can reabsorb water from its rectal contents. (pp.498)
    (From: Ramsay, J.A. J. Exp. Biol., 31.(1954), 104-13; 183-216;33.(1956), 697-708; 35.(1958),871-91.
    From this I would assume that it is unnecessary to keep Carausius in a humid environment. I have noticed that whenthey are in a humid environment they often will exude liquid from their mouths. This is probably water since it evaporates from the side of the plastic enclosure with very little residue remaining.
  • Carausius body colour can be affected by several environmental factors.
    (2): All from pp. 561 -" The epidermal cells of Carausius contains orange, red, and yellow lipochromes, green 'insectoverdins' and varying amounts of the brown ommochrome pigments ommine and xathommatine--to provide a 'morphological' colour change. (a) And each form, except the green variety, has its own range of colours, brought about by the dispersion or clumping of the brown and orange pigments within the cells--a 'physiological' colour change.(b) Normally the insect is dark at night and pale by day, and this change will continue for several weeks in complete darkness."..."High humidity also causes darkening; dry air causes pallor."(b) "These effects are indirect; they apprently depend on some nervous stimulus reaching a centre in the head and leading to the production of a hormone which causes the pigment movement in the [epidermal] cells." (b)
    "The effect of light on Carausius is excerted solely through the eyes;..."
    "Green is the most effective component of ordinary daylight in inducing the response;...."
    "The 'morphological' colour change in Carausius seems to be brought about by the same stimuli acting over a greater length of time.(b)
    a= (From: Bückmann, D. and Dustmann, J. H. Naturwiss., 49.(1962), 379.
    b= (From: Giersberg, H. Z. vergl. Physiol., 7.(1928), 657-95.
  • Parthenogenesis is the reproductive process that doesn't require mating to produce fertile eggs. (See the LifeCycle section above). This ability is universal among Phasmids (walkingsticks and leaf insects). Carausius is constantly pathanogenetic. If males appear then they are usually intersexes and are not able to copulate sucessfully. (pp. 664)
    (From: Cappe de Baillon, P. C.R. Acad. Sci., 199.(1934), 1069-70; 209.(1939), 527-9.and
    Toumanoff, K. Bull. Soc. Zool. Fr., 53.(1928), 528-44; Bull. Biol. Fr. Belg., 62.(1928), 388-411.
    These intersexes can be produced experimentally by keeping eggs at 30°C during the first third of the developmental period. (pp. 664)
    (From: Bergerard, J C.R. Acad. Sci., 253.(1961), 2149-51; Bull. Biol. Fr. Belg..,95.(1961), 273-300.


Classroom experiments with walking stick insects.

Several experiments can be done by students in the primary or secondary school classroom using walking sticks.The two listed below are "long-term" in that they require minor effort over several months. In the future I hope to find/create some other ones that are more short term.

The effect of environment on stick insect body colour

The colour of adult insects varies from almost black to very light green. This is influenced by the "colour" of their envirnment while they are growing up. This is probably an adaptive feature that helps them blend into their background and avoid detection by predators.

This can be tested/demonstrated by growing two or more groups of insects in different "coloured" environments.


  • Make two or more cages for growing several (more than 5) insects so that they are the same size and shape (two identical cages - except for colour).
  • Make each equivalent cage a different colour by painting the inside. Use non-toxic paints so you don't poison your insects and paint them long before you need to used them so that any "paint vapours" have evaporatated long before the insect are added to the cage. I suggest you start with one cage with a black (or dark brown) colour and another cage that is light green. Make the sides, bottom and lid one colour. Be sure to also make the sticks (for moulting) the same colour as the sides, too.
  • Add newly hatched insects (or young insects) to each cage and grow to adulthood in the coloured cage.
  • While they are growing make sure each cage is treated in the same way. Keep the same feeding, temperature, light/dark cycle.
  • Record your observations on the colour of each insect as it grows. This should permit you to follow any change in colour and determine when in their development the colour "decision" is made.
  • If you can get a set of paint colour sticks with a variety of colours you can make a note of which colour is closest. If you keep track of each "colour group" and record the changes as they take place with each moult.
  • Record and compare the colour of the adults. If you kept all the other environmental factors the same then any difference in body colour between the two "colour groups" should be due to the colour of their environment (e.g. black vs. green).

The effect of cold treatment (freezing) on egg hatching.

The environment can affect how well eggs develop and the frequency of them hatching. In this experiment you can test the effect of cold treatment on the likelyhood of the eggs hatching.


  • Collect eggs from actively laying females.
  • Separate these eggs into two (or more) groups.
  • Leave one group untreated - the control group.
  • Treat each group with a different cold treatment. This can be:
    • brief freezing (1 hour in a freezer at -10°C)
    • intermediate freezing (1-2 days in a freezer at -10°C)
    • long freezing (1-2 weeks in a freezer at -10°C)
  • Return the eggs to room temperature and record the number of eggs that hatch.
  • Compare the hatch rate of the cold treated group to the control (untreated).
  • What conclusions can you draw from your data?

NOTE: Cold treatment is only one of several "environment treatments" that are possible. Think of some more and test them using this experimental system. In the "Interesting Facts" section, see the effect of temperature on the appearance of male insects.

I would love to hear about the results of your experiments or any other experiments you have thought of or done.



Background/Extra Reading:

Much of what I learned about looking after walkingsticks came from the book:
A step-by-step book about STICK INSECTS
by David Alderton (1992, T.F.H. Publications),
which I found at a local, superior quality pet shop.


Other sites:


Other References:

1. D. J. Borror and R. E. White.
Peterson Field Guides - Insects. America north of Mexico.
1970. Houghton Mifflin Co. Boston.

2. V. B. Wigglesworth.
The Principles of Insect Physiology.
6th Edition. 1965.