# How is Chubby the alligators weight estimated?

There is a massive alligator in Florida that lives near a golf course, and he is estimated to be the largest alligator in Florida history assuming the estimations of his size are correct.

Estimating his length seems fairly easy, but how would they estimate his weight?

• I can understand this could fit in animal-watching, but I think it should be asked on biology.stackexchange.com Commented Oct 18, 2018 at 16:24
• If a question is in scope on two sites, then its up to the OP to decide and I have never gotten better answers as a result of migrating a question Commented Oct 18, 2018 at 16:37
• Typicallay it's estimated from the lenght of the animal, and sometimes sex or build, based on previous catches. You can try to calculate the volume of the animal from its dimensions, but that's pretty hard to do well.. Commented Oct 18, 2018 at 18:02

Chubbs, the alligator in the question, is 15 feet long, according to the OP's link. OP's source and mine: Sports Illustrated. According to this source

The state's [Florida's] biggest alligator on record is 14 feet long and 780 pounds.

The article does not say if the previous record holder (PRH) had recently ate or pooped, which might make a non-trivial difference, if the OP desires great accuracy and precision.

I'm glad the OP asked for an estimate, not a measurement, otherwise one would have to sedate the alligator and suspend him (most likely a him) in a sling attached to a spring balance.

For a zeroth order approximation for Chubbs, one would take (15/14) x 780 and get 836 pounds.

Of course Chubbs, if he had the exact morphology of the (PRH), would be larger in all three dimensions. This would give a first order approximation of (15/14)cubed x 780 = 959 pounds.

To refine that number, one would look at the largest diameter (or circumference) of both alligators and adjust accordingly. Maybe Chubbs (named after a local golfer, and not his figure) is svelte relative to the PRH -- or obese. You should be able to get a reasonable approximation to the ratio of diameters from photos, the photos normalized to a 15/14 length ratio. I don't advise using a measuring tape on an unsedated alligator.

Then the estimate of Chubbs's weight would be (15/14) x [D(Chubbs)/D(PRH)]squared x 780.

For any other alligator, use the same method with a reference alligator as close as possible in length and shape.