Ever wonder how a zoo knows the exact weight of its elephants or how tall to post a giraffe's feeder?

A zoo in Europe is providing a behind-the-scenes look at how its staff keeps track of the height and weight of its animal residents.

Needless to say, they have to get rather creative when it comes to measuring massive creatures. They don't exactly make tape measures to stretch to the top of an adult giraffe's head.

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The ZSL Whipsnade Zoo in Dunstable, England is home to a staggering 10,000 animals making it the largest in the U.K. Zookeepers and veterinarians recently invited photographers to see how it measures all of those animals during their annual weigh-in.

20 Fascinating Photos Of Zoo Animals Getting Weighed and Measured

The annual weigh-in at the U.K.'s largest zoo allows zookeepers and veterinarians to record vital statistics and track the health and wellbeing of its more than 10,000 animals.

Gallery Credit: Rob Carroll

LOOK: Here are the pets banned in each state

Because the regulation of exotic animals is left to states, some organizations, including The Humane Society of the United States, advocate for federal, standardized legislation that would ban owning large cats, bears, primates, and large poisonous snakes as pets.

Read on to see which pets are banned in your home state, as well as across the nation.

Gallery Credit: Elena Kadvany