Bar-Sided Forest Skink
The Bar-Sided Forest Skink (Concinnia tenuis) — Sydney's Garden Climber
If you live in one of Sydney's older, more established suburbs — particularly on the Lower and Upper North Shore — and you have noticed a slender, copper-brown lizard scurrying up a brick wall, you have probably seen a Bar-Sided Forest Skink (Concinnia tenuis). They are one of the more agile and arboreal members of Sydney's native skink fauna, and they thrive in the kind of mature suburban gardens that have been around long enough to develop proper structure — old trees, sandstone walls, decent leaf litter and a bit of neglected corner.
These are small, intelligent and inquisitive skinks. They are also one of the few Sydney lizards that will readily make their way into homes. At Urban Reptile Removal we get regular calls from homeowners in suburbs like Roseville, Lindfield, Killara, Pymble, Wahroonga, Mosman and Cremorne who have found a Bar-Sided Forest Skink running across a hallway, basking on a windowsill or watching them from behind a pot plant.
What is the Bar-Sided Forest Skink?
The Bar-Sided Forest Skink (Concinnia tenuis) is a medium-sized native skink common in the wet forests and adjacent suburbs of eastern Australia. Previously placed in the genus Eulamprus, it was reclassified into Concinnia following a major revision of the Australian skink fauna.
Snout-vent length: approximately 85mm
Total length: up to 200mm
Conservation status: IUCN Least Concern
Urban Adaptation Rating: ★★★★★
Activity: Diurnal, most active in spring and summer
Distribution in Sydney: Zones 1 and 3
How to identify a Bar-Sided Forest Skink
The species is named for the most distinctive identification feature — the bar-like markings along the upper sides:
Copper-brown to pale brown base colour
Small black blotches scattered across the back, varying in density between individuals
Narrow dark stripe typically present on the back of the neck
Broad black stripe along the upper sides
Deep pale notches in that black stripe that appear as vertical bars — this is the diagnostic feature
Tail bears numerous irregular, narrow dark bands
Slender, agile build
Long tail relative to body
Slightly flattened body, suited to squeezing into bark crevices and the gaps in brickwork
The bar-sided pattern is unmistakable once you have seen it. The vertical pale notches on the dark flank stripe genuinely do look like bars or rungs, and no other skink in the Sydney region has quite this pattern.
Where do Bar-Sided Forest Skinks live?
The Bar-Sided Forest Skink occupies a niche slightly different from its ground-loving relatives. They are semi-arboreal, spending much of their time off the ground in vertical structures.
Natural habitats:
Wet sclerophyll forest
Rainforest and rainforest margins
Dense woodland
Hollow logs and standing dead timber
Rock crevices and sandstone outcrops
Tree trunks and fallen timber with good bark
Urban habitats:
Established suburban gardens with mature trees, particularly on Sydney's Lower and Upper North Shore
Brick walls of older homes — this is where they really thrive
Sandstone retaining walls
Garden rockeries
Wood-pile habitats in less manicured gardens
Tree hollows in old garden trees
Climbing brickwork — the real story in the North Shore suburbs
The semi-arboreal habit of the Bar-Sided Forest Skink takes on a particular character in Sydney's older suburbs. On the Lower and Upper North Shore, where so many homes are built from double brick, these lizards have found themselves a near-perfect habitat.
Double brick construction creates a small cavity between the inner and outer layers of bricks. For an agile, slightly flattened skink like the Bar-Sided Forest Skink, this gap is highway and shelter rolled into one. The lizards climb the external brickwork easily, slip into the cavity through small gaps in the mortar or around windows, and can move freely up the wall — including from the ground floor to the first floor — through that internal cavity.
This is why the species is so frequently encountered in homes on the North Shore but much less commonly seen elsewhere. The combination of mature gardens, old established sandstone foundations, and double brick construction creates a habitat that suits them so well that they have become a quiet but consistent presence in tens of thousands of homes across the region.
If you find one upstairs in a North Shore house, the most likely explanation is that it has come up through the brick cavity from a ground floor entry point.
When they come inside
Bar-Sided Forest Skinks are one of the few Sydney native lizards that genuinely will enter homes. They are curious, intelligent and small enough to take advantage of gaps that most reptiles cannot. We see them coming inside through:
The brick cavity in double-brick construction
Gaps under and around external doors
Air vents, particularly older brick vent grilles
Gaps where pipework enters external walls
Open windows without screens
Once inside, they tend to head for warm, quiet spots — behind appliances, in laundries, on north-facing windowsills, behind pot plants. They are very rarely a problem. If you find one in your home, the simplest solution is usually to open a door or window and gently encourage it back outside.
Behaviour and agility
The Bar-Sided Forest Skink is known for its speed and agility. They are exceptional climbers, moving easily up tree trunks, sandstone walls and brick. When approached, they typically retreat upward or into a nearby crevice rather than running across open ground.
They prefer dappled sunlight rather than full exposure — basking habits suited to a forest-edge species. Look for them on the sunny side of a tree trunk in mid-morning, or warming themselves on a sandstone wall in the late afternoon as the angle of light comes in through the canopy.
The combination of vertical retreats, dappled basking sites and dense ground cover means they can persist in gardens that have lost most of their other native reptiles. They are one of the more durable urban species.
Diet and lifestyle
Bar-Sided Forest Skinks are opportunistic insectivores. Their diet includes:
Insects of all kinds
Spiders
Small invertebrates from leaf litter
Occasionally soft fruits and plant matter
Carrion when encountered
Their hunting style suits their semi-arboreal habits. They forage along tree trunks, fallen logs and brickwork, picking off invertebrates moving across the surface, and they also drop to the ground to hunt through leaf litter.
Co-existing with Eastern Water Skinks
One of the interesting things about the Bar-Sided Forest Skink is how it shares space with the Eastern Water Skink (Eulamprus quoyii) in urban gardens.
The two species:
Often occur on the same property
Are similar in size
Have overlapping diets
Are both diurnal and most active in warmer months
But they avoid direct competition by using different microhabitats:
Water Skinks stay low — basking on rocks near water, retreating into ponds, hunting on the ground
Forest Skinks go higher — basking on tree trunks and brick walls, sheltering in hollows, bark crevices and brick cavities, hunting up off the ground
This vertical partitioning is part of what makes a mature, structurally complex garden so good for biodiversity. Each species finds its niche, and both can persist on the same suburban block.
Are Bar-Sided Forest Skinks dangerous?
No. The Bar-Sided Forest Skink is completely harmless to humans and pets. They have no venom, no significant defensive bite, and they actively avoid contact. They are too agile to be easily caught, and if handled will struggle, drop their tail and try to escape — none of which can hurt you.
As with all native reptiles, the risk runs the other way. Cats take a major toll on Forest Skinks, particularly those caught moving between cover. Garden pesticides reduce their prey base. And loss of mature trees, hollow logs and untidy garden corners directly reduces the habitat that supports them.
Breeding and reproduction
Bar-Sided Forest Skinks have a reproductive strategy similar to other Concinnia and former Eulamprus species:
Mating: Occurs in late summer
Live-bearing: Females give birth to live young rather than laying eggs
Litter size: Approximately seven offspring
Timing: Young born soon after mating, late summer to early autumn
Independence: Fully independent at birth
The live-bearing strategy is shared with the Eastern Water Skink and is thought to be an adaptation to the cooler, wetter climates these species evolved in. Carrying developing young internally allows the female to control their temperature through her own basking behaviour.
What to do if you find a Bar-Sided Forest Skink at your home
Leave it alone. Bar-Sided Forest Skinks are excellent garden residents — beautiful, harmless, beneficial and a sign that your property has the habitat structure to support a healthy reptile community.
If you find one inside the house, simply open a door or window and gently encourage it toward the exit. They are intelligent enough to find their way out on their own once they have a clear path.
Practical steps to encourage them:
Keep some mature trees with good bark and accessible hollows
Leave fallen logs and untidy corners rather than clearing every garden bed completely
Maintain sandstone walls and rockeries — these are prime habitat
Avoid pesticide use, which reduces their prey base and accumulates in the food chain
Keep cats indoors, particularly at dawn and dusk when skinks are most active
What you should not do:
Do not kill them. They are protected native wildlife.
Do not relocate them. Bar-Sided Forest Skinks are territorial and a relocated animal often does not survive.
Do not assume that "tidying up" the garden helps wildlife. Mature, structurally complex gardens with deadwood and hollows support more native species than sterile manicured spaces.
Summary
The Bar-Sided Forest Skink (Concinnia tenuis) is one of Sydney's quiet success stories — an agile, semi-arboreal native lizard that has adapted brilliantly to the older suburbs of the Lower and Upper North Shore, where mature gardens and double-brick homes provide near-ideal habitat. The cavity in double-brick walls gives them a vertical highway that lets them move freely up and through homes, often turning up on first floors after climbing inside from the ground. Their curious nature means they are one of the few Sydney lizards that will readily come inside — usually harmlessly, and usually departing on their own once you open a door. Their presence is a good sign that your home and garden retain the structure to support a functioning native ecosystem.
Found a reptile you need identified or removed in Sydney? Urban Reptile Removal operates 24/7 across the Greater Sydney region. We are fully licensed and insured, and we can identify and safely manage any reptile you encounter. Call 0418 633 474.
