Do iguanas dig holes? Iguana burrows explained

I get this question a few times a week, usually from someone standing over a fresh hole at the edge of their yard. Do iguanas dig holes? Yes. They are serious diggers. On the canal lots I work in Boca, Delray, and Lake Worth, digging is the damage that costs people real money, not the chewed hibiscus.

An iguana isn't burrowing to annoy you. It digs for two reasons: to nest and to shelter. A female needs loose soil to lay eggs. Both sexes will dig a den to hide from cold, from hawks, and from dogs. Put those instincts next to a warm seawall and a sunny bank, and you get tunnels running straight under things you paid a lot to build.

The part that catches people off guard is how much soil one lizard moves. A single burrow can go several feet back and shift a wheelbarrow's worth of dirt. When that dirt comes out from behind a seawall or under a pool deck, the ground on top loses its support, and that's when you see cracks and slumps.

What does an iguana burrow look like?

Once you've seen a few, they're easy to spot. The opening is usually a wide, flattened oval or a half-moon shape, not a neat round rodent hole. A grown green iguana is a big-bodied animal, so the entrance is often four to eight inches across, sometimes bigger where two burrows join.

The dead giveaway is the fan of loose soil spread out below the opening, like someone kicked dirt down a slope. That spray is the material the iguana hauled out. On a canal bank you'll see it fanned toward the water. Along a foundation you'll see it piled against the wall.

Here's where I look first on a South Florida property:

• Right at the waterline along a seawall cap, where warm concrete meets soft fill
• In the slope of a canal or lake bank, often just above the water
• Against the foundation of the house, the pool deck, or a paver patio
• Under AC pads, sheds, docks, and the lip of a bulkhead
• In sunny landscape beds with loose, sandy soil and good drainage

Why iguana burrows matter more than the holes look

A hole in the lawn is easy to shrug off. The problem is what the tunnel does out of sight. Iguanas dig into the fill behind a seawall, and that fill is the whole point of the seawall. It holds the ground back. Hollow it out and the wall starts to bow, the cap cracks, and the soil above sinks. I've seen tie-back seawalls fail early because the dirt behind them got turned into a lizard apartment complex.

Pool decks and patios are the same story. The slab is only as solid as the ground under it. When a burrow runs under a paver deck, the pavers dip and you get a low spot that pools water after rain. Under a poured deck you get hairline cracks that grow.

Foundations are the scary one. Most home slabs handle small voids fine, but a network of burrows against the footing, plus our sandy soil and heavy summer rain, is not a combination you want to ignore. Water follows those tunnels and washes out more soil every storm.

I'll be straight with you on the money side. Homeowners insurance usually treats this as gradual damage from vermin, which most policies exclude. I've watched plenty of claims for seawall and deck settling get denied for exactly that reason. Read your policy, but don't assume you're covered. Catching burrows early is a lot cheaper than a seawall repair.

How deep do iguanas dig, and when?

Depth varies with the animal and the soil. A shelter den is often one to three feet deep. A serious nesting tunnel can run longer, and a determined female will dig a system with more than one entrance and side chambers. In loose canal fill they move fast, and one burrow can stretch four to six feet back from the opening.

Nesting is the busy season. Down here females dig nests roughly from late winter into early summer, with a lot of activity in spring. That's when I get the most calls about sudden holes appearing near seawalls and in flower beds, because the females are hunting for warm, sandy spots to lay. One clutch can be a few dozen eggs, so a good nesting site turns into a repeat problem year after year if you don't shut it down.

The other thing to know: iguanas reuse burrows. If you just fill a hole and walk away, the same lizard often digs it right back out within days. The soil is already loose and it knows the spot.

How I handle an active burrow

Filling the hole is the last step, not the first. The order matters, and doing it out of order is why so many DIY fills fail.

First I make sure nobody's home. I check whether the burrow is active and whether it's a nest with eggs. You cannot properly collapse a tunnel with an animal or a clutch inside, and in Florida the removal has to be done the legal, FWC-compliant way. Green iguanas are a nonnative species here, but there are still humane and legal rules about how you take them, which is a big part of why I stay licensed.

Then I deal with the residents. That usually means trapping or removing the iguanas using the burrow, and checking nearby holes, since one animal often keeps two or three.

Only then do I collapse and pack the tunnel. A proper fill means running the length of it, not just plugging the mouth. Here's the way I do it:

• Confirm the burrow is empty of animals and eggs before touching it
• Collapse the tunnel along its length, not just the entrance
• Pack in compactable fill in layers and tamp it down hard, not loose topsoil
• Wet and re-tamp so the fill settles instead of sinking on you later
• Where it's at a seawall or foundation, use proper fill and check for washout after the next big rain
• Mark the spot and watch it, because reuse in the same area is common

A word on cleanup and salmonella

Iguanas carry salmonella, and their droppings pile up in and around burrows. When you're digging out an old tunnel you're stirring up soil that's been sitting under that. Wear gloves, keep it away from your face, wash up well after, and don't let kids or pets play in a fresh dig. It's not a reason to panic, just a reason to be sensible about hand-washing.

If you're seeing repeat holes along a seawall or the foundation, that's worth a look before the next storm season loosens things up. I do a free walk of the property, tell you honestly whether it's cosmetic or something that needs real fill and follow-up, and go from there. Removal starts at $125, and I keep a monthly monitoring option at $99 for waterfront lots that fight this every spring.

You can reach me at (561) 735-1975. I cover Palm Beach and Broward, and canal properties are most of what I do.