Not all burrows are equal
A basking or shelter burrow is one thing; a nesting burrow is another entirely. In spring, a gravid female digs a substantial tunnel — often several feet long, sometimes with multiple chambers and entrances — to lay her clutch of eggs. These are typically the largest, deepest burrows on any property.
That size is what makes them the most dangerous to structures. A single nesting tunnel driven under a slab, a seawall cap, or a lake bank can remove enough soil to undermine that structure in one season, where smaller shelter burrows would take much longer.
Nesting marks a population about to jump
A nesting burrow is also a warning sign about numbers, not just structure. A single clutch can be dozens of eggs, so a bank or bed full of nesting activity is where a couple of iguanas is about to become a colony. The damage and the breeding surge come from the same spot.
Where and when to look
- Peak nesting runs through spring, so late winter through early summer is prime inspection time
- Check soft, sunny, well-drained ground — bank faces, bed edges, bunker faces, canal shoulders
- Nesting burrows are the widest openings, often plate-sized, with heavy spoil piles
- Multiple entrances close together frequently mark a single large nesting tunnel
Collapsing them does double duty
Dealing with nesting burrows around the nesting season accomplishes two things at once: it removes the biggest structural voids on the property, and it interrupts the breeding cycle before a clutch hatches into the next wave of iguanas. That combination is why we prioritize nesting-area burrows over ordinary shelter holes when we're reducing pressure on a property.
Common questions
Why are nesting burrows more damaging?
Females dig much larger, deeper tunnels to lay in, so nesting burrows are the biggest single voids on a property and the most capable of undermining a slab, seawall cap, or bank in a single season.
When should nesting burrows be dealt with?
Around the spring nesting season. Collapsing them then removes the void and breaks the breeding cycle before a clutch of eggs hatches into the next wave of iguanas, so the timing matters for both damage and numbers.
How do I tell a nesting burrow from a regular one?
Nesting burrows are the widest openings on the property — often dinner-plate sized — with heavy fanned spoil dirt and sometimes several entrances feeding one large tunnel, dug into soft, sunny, well-drained ground.
