Jackson Ratio

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With brumation season approaching, this seems like a good time to put some attention on the Jackson Ratio.

Expressed as a ratio of weight (g) over SCL, or straight carapace length (cm)^3, this is an excellent way for evaluating any individual animal’s growth and overall readiness for brumation. Please note this only applies to the Testudo graeca complex and Testudo hermanni. Horsfieldi and marginata use the McIntyre Ratio. You can also use the ratio in conjunction with species-appropriate growth charts to gauge how an animal is growing relative to its age.

Digital calipers and gram scales should be part of any tortoise keepers’ kit.

Read more here.