body condition
A measurement that can be used to infer the health status of an organism. This is typically calculated by comparing a measurement like length to another like weight, for which a healthy ratio is known.
The human body-mass-index (BMI) can be considered a measurement of body condition, as this is derived from a person's height and the range of weights that are considered to be healthy for that height.
A fish with a high body condition is likely to be on the plump side with excess energy stored as a buffer for times of low food intake or high energy use, while a fish with low body condition would be skinny for its length and have low energy reserves.

These are found only in tropical and subtropical regions where corals can thrive and continue to build up a reef at a rate that keeps pace with the erosion and subsidence of the underlying volcano.

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