BOSTON (CBS) — How does an anaconda get a physical examination?

New England Aquarium biologist Ryan McAndrews says their first step in the process Thursday morning was to make sure the snakes are “quiet.”

“We started early this morning. We sedate them. Once they’re quiet enough to transport we put them in a bin, bring them upstairs and wait until they’re really quiet,” McAndrews said. “Then we can put them on the floor and measure their length and weight.”

Biologists at the New England Aquarium measure the length of one of the anacondas. (Photo credit: Carl Stevens/WBZ NewsRadio 1030)

McAndrews says they do the annual anaconda exams because these snakes are also growing.

“Every year we pull the snakes out and get them weighed, measured, check the pick tag that helps track them. Also we take some x-rays and do some blood work to see how they’re doing,” McAndrews said. “It’s good to see how fast they grow depending on how much we’re feeding them and you can also track how old they are.”

He says the anaconda is a fairly slow moving animal.

“They’re relatively quiet animals and they don’t make noise. So, it’s hard to tell if they’re not doing so well,” McAndrews said.

The anaconda is the largest snake in the world, some grow over twelve feet long and weigh over 100 pounds.

“They’re the heaviest snakes per length,” McAndrews said.

WBZ NewsRadio 1030’s Carl Stevens reports