It depends on the type of damage
There isn't one speed, because iguanas cause two very different kinds of damage on very different timelines. Grazing and fouling are fast; structural undermining is slow. Understanding which clock you're on helps set expectations for how urgent your particular problem is.
Grazing and fouling are fast
The visible, above-ground damage happens quickly. A group of iguanas can strip a hibiscus, bougainvillea, or a fruit crop in a matter of days, and droppings foul a pool deck or dock the very first time they bask there. This is the damage owners notice fastest because it changes the look of the property almost overnight.
Structural damage is slow but compounding
Undermining is the slow clock. It builds over weeks and months as burrows expand, branch, and multiply and the soil support gradually disappears beneath slabs, seawalls, and banks. A single burrow does little quickly, which is exactly why owners tend to under-react to the early holes.
- One shelter burrow: minimal, slow effect on structure
- A growing network over months: real undermining of slabs and banks
- A nesting burrow in spring: large void in a single season
- An expanding population: many burrows and heavy grazing at once
The breeding cycle is the accelerator
The thing that speeds everything up is population growth. A couple of unmanaged iguanas can become a colony in a season, and more animals means more burrows and more grazing happening simultaneously. So while a single iguana does little on its own, an established, growing population does a lot — and the total damage compounds the longer it's left alone. That compounding is the whole case for acting early rather than waiting to see how bad it gets.
Common questions
How quickly will iguanas wreck my landscaping?
Grazing damage is fast — a small group can strip flowering plants or a fruit crop within days — and droppings foul decks and docks the first time the animals bask there, so the visible damage often seems to appear overnight.
How long before burrows threaten hardscape?
Structural damage builds over weeks and months as burrows expand and the population grows, so a single hole does little quickly but a growing network compounds into real undermining of slabs, seawalls, and banks the longer it's left.
Why does everyone say to act early?
Because the damage compounds. A couple of iguanas become a colony in a season, and more animals mean more burrows and grazing at once, so early action stops a small, cheap problem from turning into a large, structural one.
