Is husbandry best approached as details or holistically?

You may have noticed a decrease in discussions of piece-meal, basic care requirements — enclosure size, temperatures and humidity levels, substrate options, all kept relatively simple — and an increased focus on various approaches to husbandry that are more holistic, or emphasize enrichment — bioactive approaches are the most notable development here, but the rise of “kits” tailored to specific herps is certainly related.

Hold onto that distinction between simple itemized care and holistic enriched care for a minute; I want to talk about it in a bit of a roundabout way.

A recent research article in the journal Applied Animal Behaviour Science “compared the effects of housing conditions (Standard vs. Enriched) on the behaviour and welfare of captive leopard geckos (Eublepharis macularius).” 

Six leopard geckos were each housed singly for four weeks in each of the following enclosures:

Standard — vivariums contained a small rock hide, a small water bowl that the animals could not submerge in, a newspaper substrate, and a calcium bowl. 

Enriched Non-naturalistic — vivariums had four different hides, including one hanging hide and a moist hide, a large water bowl big enough to submerge in, fake plants (three types), and a calcium bowl. The substrate was a “topsoil” (actually, Arcadia bioactive mix and coco fiber) x sand mixture. 

Enriched Naturalistic — these vivariums were identical to the Non- Naturalistic condition except that they contained live invertebrates to break down the matter (Collembola spp springtails, Trichorina dwarf isopods and Porcellio sp isopods, Mealworms, small and giant lob worms) and real plants (seven species).  This design is exactly what would be called “bioactive” in many hobby groups.

Each were wooden vivariums with sliding glass fronts (L61 x D46 x H46cm; 24 x 18 x 18 inches), with a ceramic heater thermostatically controlled to create a basking spot of 31C (88F), and a 2% UVB lamp running 12 hours per day.  There is no mention of any supplementation aside from the free choice calcium and UVB — that is, there is no note that any Vitamin A was provided, but the geckos were fed exclusively locusts which are one of the few feeder insects with possibly sufficient levels of Vitamin A.  There is no note of whether the plants in the Enriched Naturalistic enclosures were watered; this might be relevant to the RH and substrate moisture levels in the enclosures, which were not noted and apparently not measured.

The researchers found that geckos with a larger water bowl available would soak in it, whereas with a smaller water bowl they would try to soak but be unable to because they didn’t fit in the bowl.  The researchers write that “This suggests that they were highly motivated to perform this behaviour and that thwarting this need would likely compromise welfare.“ It was also noted that the small bowl condition led to more water being drunk.  

In the Enriched enclosures, the geckos used all the elements (rotated between all the hides, for example), though the geckos did not hide, move or eat more or less in any of the enclosure types.
More of the geckos’ time was spent in wall climbing and other escape/boredom behaviors in the Standard enclosures, “possibly due to a lack of stimulation within their home environment.”
But they found that “No significant differences existed between the Non-naturalistic and Naturalistic conditions in any of the behaviours, including enrichment-specific behaviours that could only be exhibited within the Enriched conditions.” That is to say, there was no difference in behaviors between the Naturalistic and Non-naturalistic enclosures.  

At the end of each gecko’s three month experience, each was given a “preference test”, which  “consisted of the animal being given access to three connected vivariums, each replicating one of the housing conditions”. It was found that the geckos spent more time in the Enriched Naturalistic section — roughly 75% of their total time.  This was taken to indicate that the geckos preferred that enclosure design over the others (this is a standard way to discover animals’ preferences; I can’t think of a better way, really).

Those are the facts the researchers reported.  They also drew at least two evaluative conclusions: 
“(W)e recommend keeping leopard geckos in Enriched enclosures of at least 46 cm in height. These should contain a range of shelters/hides, climbing opportunities, and a water bowl sufficiently large to immerse themselves in fully.” 

“The preference test revealed a strong preference for the Naturalistic environment; therefore, naturalistic features (e.g., live plants, live invertebrates) should be incorporated where possible.”
It is worth observing that the study didn’t compare enclosure dimensions, so any recommendation on this topic is not supported by their specific findings.   

One fact that’s obvious is that the Standard enclosure was simply completely inadequate; it did not even contain a moist hide.  That the geckos exhibited escape behaviors from a plainly bad enclosure does not need empirical research to explain.  That geckos with no moist hide would drink more water is not unexpected, and no appeal to a larger water bowl is needed.

The Enriched Non-naturalistic enclosure did have a moist hide, and also wasn’t simply bare bones.  It is not surprising that the geckos behaviors were less troubling in such an enclosure; what is surprising is that the researchers didn’t take this enclosure as the baseline, since it is a pretty basic setup per established practices.

Published accounts of leopard geckos natural history notes that they are most likely to come out of hiding at RH of 70-80%.  This might be taken to suggest that that is the RH that leopard geckos prefer, and would explain the soaking behavior in the larger water bowl in the Enriched enclosure (I have kept scores of leopard geckos and never seen one attempt to soak).  This moisture preference is the obvious reason the study subjects preferred the Enriched Naturalistic enclosures; an enclosure with live plants is, ceteris paribus, going to be more humid than one without.  

Their preference is not necessarily for live plants themselves (which are few and far between in much of their natural habitat).  This preference is certainly not for substrate microfauna, unless of course the geckos were eating some of the larger species; this would be a preference more for a varied diet than supposedly waste-consuming microfauna, which need not be tied to a bioactive methodology.  This finding of leopard geckos’ preference was a very complicated and misleading way to show that leopard geckos appreciate more moisture than they’re often given in captivity.

The point here is not simply to call out a published study of embarrassingly poor design (though it is that).  The point here is that we don’t need research to figure out that leopard geckos shouldn’t be kept in bare boxes, nor do we need any sort of holistic approach like so-called bioactive enclosures to provide for geckos’ — or any herps’ — needs.  We can continue to figure out what specific needs our herps have and provide for those needs without buying a “kit” made of stuff or ideas some marketer is selling.


Khan, Muhammad S. Natural history and biology of hobbyist choice leopard gecko.
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Rickman, Erin L. et al. The impact of enriched housing on the behaviour and welfare of captive leopard geckos (Eublepharis macularius).  Applied Animal Behaviour Science Volume 283, February 2025.