How to Stop Madagascan Hissing Cockroaches Escaping

Petroleum jelly is the standard answer to a climbing cockroach, and on a Madagascan hisser it is the answer most likely to slide down the wall and stop working. These animals want a heat mat running all year, and warmth is what makes petroleum jelly flow. A band that has crept down the tub is thinner at the top and narrower overall, and either failure is enough. The dependable fix is not a better barrier. It is a lid that physically closes, with ventilation you have covered yourself, and a barrier kept only as insurance for the minutes the lid is off.

Why they can walk up smooth plastic

A hisser's foot carries three systems. Four friction pads, the euplantulae, run along the tarsus and grip when the animal pushes. A triangular adhesive pad, the arolium, sits at the tip and does the work when it pulls. Two claws hook anything with texture. Van Casteren and Codd tested the species on ten surfaces in 2010, measuring the force needed to lift an animal off each one. The strongest pull-off came on acrylic scored or hatched at one centimetre spacing and on oak, where the claws could catch an edge while the pads stayed flat. The weakest came on smooth acrylic, on acrylic abraded with sandpaper and on solid Teflon, none of which separated statistically. Glass came next, ahead of the abraded surfaces and Teflon, though not separable from smooth acrylic.

Be clear what that measures. Lifting an animal off tests the arolium, the pulling system; climbing a wall is mostly the euplantulae working in shear, and nobody has run that test. It is the best evidence there is, not direct evidence about climbing.

Two things still follow. Fine scratches do not help them, so roughing up the walls achieves nothing and a scuffed second-hand tub is no worse than a new one. What helps them is structure at the scale of a claw: moulded ribs, an embossed logo, the ledge under a rim, a proud bead of sealant, a thermostat probe cable coming in over the edge. Look at your enclosure with that in mind and the ladder is usually obvious.

The lid does most of the work

Barriers get the attention and the lid decides the outcome. Hissers are wingless at every stage, so everything that leaves a tub walks.

Snap-fit tubs of the Braplast type clip onto the rim the whole way round and arrive unventilated, so every opening is one you cut and cover yourself. Gasketed clip boxes shut beautifully and then need a ventilation window cut through them, which puts you back where you started: a gasket is worth what covers the hole, no more. Loose-lidded boxes and glass tanks with a screen top are the weak designs, so check the corners and anywhere the lid rides up over a moulded handle.

Bond the covering instead of taping it: tape adhesives lose their grip in a warm humid box and lift at one edge. Aluminium or stainless insect mesh bedded into aquarium silicone and tooled flush lasts, screw-in vents make the grille part of the fitting, and vent plugs close an opening down without covering it. Size the aperture for a first instar nymph, not an adult. How much airflow to give is a separate question, covered in the guide to ventilation and humidity.

The lid-off minutes are the obvious exposure. Feed and mist with the tub standing inside a larger empty box, so anything that gets out lands where you can reach it.

What each barrier actually does

Petroleum jelly

It does not work by being slippery. It works because a thick, mobile layer cannot transmit force: the foot presses, the material shears sideways, nothing happens. Depth is the whole mechanism, so a thin smear is not a weak barrier, it is no barrier. In its favour it is in every chemist and harmless to handle. Against it, the band collects substrate, frass and shed skins until it is a textured surface with footholds in it, which with loose leaf litter happens fast.

Oils

Baby oil, mineral oil and cooking oil are the weakest options here. They run off a vertical wall quickly. Betz and colleagues replaced the natural foot secretion of this species with oily liquids in 2017 and measured adhesive tenacity going up, not down, and on the whole-animal test pure oils produced excessive friction. Neither result is about oil on a wall, but nothing in it points to oil weakening their grip. And oil is an insecticidal mode of action in its own right, since horticultural oils act on the respiratory system by getting into and occluding the spiracles. That is true of any grease, which is why a barrier belongs high on the wall and out of their path.

Silicone grease

The same idea on a different base, asking two things of the material at once: yield under a foot, and hold still for weeks on a warm wall. Food-grade silicone grease is rated across a far wider temperature range than petrolatum, and it is what experienced roach keepers converge on for heated colonies. Nobody has measured a silicone band against an animal this heavy, so it is a better bet on a heated wall, not a proven barrier. It also contaminates plastic, so degrease before bonding anything to that wall later.

PTFE dispersion

Fluon and the ant-keeping equivalents are a waterborne PTFE dispersion, painted on and left to dry into a thin film. It is what insect laboratories and ant keepers reach for, it is dry, and a heat mat does nothing to it. What it does not have is evidence on hissers. The one measurement that touches it put solid Teflon level with plain smooth acrylic, and that was a pull-off test on a sheet, not a dried film in shear, so it neither convicts nor clears it. Add that humidity shortens the film's life and that a hisser enclosure is humid, and it earns a place as a second line. The same caution covers talc in ethanol: published, better than Fluon against small ants, never tested on anything this size.

Heat is what breaks a petroleum jelly band

Hissers are the awkward case for a petroleum jelly barrier: they need a thermostatted mat on one side all year, so one wall never cools. Husbandry numbers are in the hissing cockroach care guide.

The specification figure for petroleum jelly is a drop melting point of 38 to 60°C. That is where the first drop finally falls from a test thermometer, not where the material begins to move. It softens well below it, and a softened band on a vertical wall creeps downwards under its own weight.

Two things then go wrong. The band loses its top edge and narrows as it travels, and a band narrow enough to step over has stopped being a barrier, which on an animal six centimetres long does not take much. And the mass that has moved ends up in a roll along the bottom edge, where every gram is a gram no longer defending the top.

What to do about it:

• Run the mat on a thermostat. An unregulated mat against a tub wall gets hotter than people assume.
• Mount it on one side above substrate level, never underneath, so the animals keep a cool floor to retreat to. The band on that wall is the part that moves first, so check it there.
• Keep the band narrow and high instead of deep. It still has to be thick enough to shear under a foot, but a tall fillet carries more mass and slumps sooner.
• Inspect it monthly, and when it needs redoing wipe the old band off first.

What I would use

In order of return on effort: the lid, then what covers the ventilation, then your handling routine, and only then a barrier. A tub whose lid closes, with bonded mesh or screw-in vents, settles it outright and never needs topping up.

If you want a barrier as well, the property to optimise on a hisser is temperature stability, because the heat is permanent. Food-grade silicone grease is the option that fits, on reasoning and keeper experience and not on measurement. Petroleum jelly is the available fallback and it does work, treated as a consumable: narrow, high on the wall, thick enough to shear, on the coolest side, inspected monthly. PTFE if you would prefer something dry, on the understanding that it is unproven here. Not oil.

Barriers are the part of the system that degrades. A lid does not.

Common questions

Does Vaseline stop hissing cockroaches climbing?

Yes, while it is deep, clean and still where you put it. It works by shearing under the foot instead of gripping, so the layer has to stay thick. A thin, dusty or slumped band stops working, and in a heated tub that happens sooner than most people expect.

Why does my petroleum jelly barrier slide down the tub?

Because it is warm. Petroleum jelly has a drop melting point of 38 to 60°C and softens long before it reaches that, so a band on a heated wall flows downhill. A side-mounted mat without a thermostat is the usual culprit. Move it above substrate level, put it on a stat, or change to food-grade silicone grease, which holds its consistency at heat mat temperatures.

Is silicone grease better than Vaseline for hissers?

On temperature, yes: it is rated across a far wider range and will not slump while the mat is on, and keepers with heated colonies tend to prefer it for exactly that reason. On whether it stops a hisser better, nobody has tested it, so treat it as the more reliable version of the same idea and not as a guarantee.

Is it a problem if one escapes in the UK?

They are legal to keep with no licence, and a hisser loose in a British house dies; it does not establish. Even so, in England and Wales section 14(1) of the Wildlife and Countryside Act 1981 makes it an offence to release or allow to escape into the wild an animal of a kind not ordinarily resident in, and not a regular visitor to, Great Britain in a wild state, with a defence at section 14(3) for anyone who can prove they took all reasonable steps and exercised all due diligence. Scotland and Northern Ireland have their own versions. Sealing the tub is part of taking those steps.

If you are still choosing an animal, the guide to the best pet cockroaches for beginners covers which species climb: adult domino cockroaches manage it and their nymphs cannot. The rest sits in cockroaches for sale, and tubs, vents and substrate are in the accessories section.