EXPERT OPINION

You don’t have to be in the reptile keeping hobby long to hear the dreaded word: impaction. But what do we know about it really?

Impaction, in short, is a blockage in the gastrointestinal tract. You can think of it as severe constipation. It doesn’t take long for lack of bowel movement to cause some pretty serious health issues. Investigations into many captive reptiles that had sadly perished from this condition often revealed that the blockage consisted of ingested substrate.

This put a black mark over the use of loose particle substrate for many people, and this is still the train of thought for many today. It’s no wonder that the use of solid substrates became a highly rated recommendation. This includes things like tiles, reptile carpets, and paper towels.

While these materials can and have certainly done the job, and still have some recommended applications, they just aren’t true to nature. Creating a naturallooking environment in captivity isn’t just nice for us to look at, it’s stimulating for our animals – who are more cognitive in response to their environment than we may have thought. Some studies have found, for example, that: captive geckos benefit from increased behavioural opportunities provided by their enclosures

These behaviours include activities such as digging, burrowing, and foraging for food – all of which a loose substrate provides. Reptiles also seek areas to dig and lay their eggs naturally. Recommendations from a Reptile Enrichment Workshop stated that substrates should be “as close as possible” to the species’ natural substrate, and did not list impaction as a related hazard of this practice

It is suggested that deliberate eating of the substrate by lizards may be caused by under-stimulating environments, or even malnutrition. This brings to light the other factors that go into making an ideal living enclosure to keep reptiles feeling both equally secure and interested.

At the end of the day, we need to look beyond substrate as the sole cause for this condition. Wild reptiles are not dropping dead left and right with blocked intestines. Impaction can be caused by multiple issues surrounding general husbandry, including inadequate heating and lighting for digestion, poor nutrition, and parasites.

Selecting an appropriate loose substrate is also important, which requires sound knowledge on the habitat composition of the species in question and selection of an animal-safe product. A solid substrate does sometimes have its place, for instance quarantined, hatchling or sick reptiles – but for the rest of the time, they will benefit from a more interactive environment that allows them to thrive rather than just survive.