How to Measure Snout-Vent Length on Iguanas

Measuring from the tip of the nose to the end of the tail is a way to gauge the size of an iguana.

Having pets requires keeping tabs on their overall health and well being. Iguanas are pets that typically require less work than dogs or cats, but you still need to assess them on a continual basis to ensure they are healthy. You can use the Snout Vent Length measurement, or SVL, to check on the age and size of an iguana.

Things You'll Need

• Blanket
• Tape measure

Instructions

1. Locate the parts of your iguana for which you need to measure the SVL. The snout of is the tip of the nose. The vent, also referred to as the cloaca, is located on the underneath of the tail. To find the vent, look towards the tip of the tail to find the opening where the animal urinates.

2. Take the iguana out of its cage or housing structure gently. Do not scare or startle the animal. Visually inspect the iguana's claws to verify that they are trimmed down prior to attempting to handle the animal.

3. Place the animal on a clean blanket or towel if you have a docile iguana that will stay. Have another person gently but firmly hold the iguana still while you run a tape measure the length of the animal from the snout to the vent. Mark down this measurement.

4. Take a second measurement to ensure accuracy. While the iguana is still out of the cage and on the blanket, place a mark on the blanket where the snout is as the animal is standing there. Place a second mark for the vent. You may need to slide a handheld mirror under the tail to verify exactly where the vent is located. Measure the distance between the two markings. Add the two measurements together and divide by two to obtain the average SVL of your iguana based on your measurements.

5. Compare the obtained SVL to other iguanas, knowing that males grow larger than females and can reach up to six feet in length. Iguanas grow with age and the average SVL for a one-year-old iguana is roughly 8-9 inches and a seven-year-old iguana can reach an SVL of 20-24 inches. If your iguana is too far off from average SVL measurements, remeasure the animal or schedule an appointment with a veterinarian that specializes in iguanas or other small animals.

Tips & Warnings

• Always handle your iguana as you would any other pet, with care and compassion.

• Do not get an iguana as a pet if you do not have the time, money, space or ability to properly care for the animal.

• Do not release a pet iguana in to the outdoors if you no longer wish to keep the animal; contact an animal shelter in your local area for advice.

References

• Suffolk County Community College: Iguana Anatomy
• SPCA International: Iguana Companion Guide
• Green Iguana Society: Glossary of Iguana Terms
• Melissa Kaplan's Herp Care Collection: Iguana Age and Expected Size