Halloween in the Wild

by Rachael Prokop

October 30, 2015

It’s Halloween, and you know what that means… costumes! In the spirit of the holiday, we decided to hold a costume contest for the animal kingdom.

There are lots of creatures out there who wear a disguise every day of the year, usually to avoid getting eaten. In the animal kingdom, this is called “mimicry” and it can be a pretty successful strategy to avoid predators (or, in a few exceptions, to lull prey into thinking you’re NOT a predator).

Without further ado, the winners of the 2015 Greenpeace Animal Costume Contest are…

Ant Mimicking Jumping Spider

Source: Yogendra Joshi/Wikimedia Commons

Scariest Costume: Ant-mimic Jumping Spider

There are over 300 types of spiders that mimic ants. Apparently in the bug world, ants are scarier than spiders, so palling up with them helps protect the hapless spider from things that want to eat it.

I’m sure in spider society this is absolutely terrifying, so I’ll award you the “Scariest Costume” even though you look ridiculous holding your legs above your head and pretending they’re antennae. Try harder next year, Spider.



Source: Parag Giri/Flickr

Grossest Costume: Macrocilix Maia Moth

This moth looks like two flies on bird poop.

I guess it’s probably pretty effective at deterring predators. I definitely wouldn’t eat this.

But ew. Enjoy your award for being disgusting, Moth.


Most Convincing Costume: Cinereous Mourner

See this caterpillar happily wriggling on a bed of leaves?

That’s totally a caterpillar, right? A big hairy caterpillar in bright colors that just scream “I’m toxic!” to predators.


It’s not even an insect.

Full video

This cute little guy is a baby cinereous mourner, a species of bird that lives in the Amazon. Adults are a drab grayish color, but the helpless babies masquerade as poisonous caterpillars.

Here’s a close-up:

Photo credit: Santiago David Rivera

When I first saw this little guy wriggling around in his nest, I was 100% convinced I was looking at a caterpillar, right until he opened his tiny beak. Little Cinereous Mourner wins my prize for the most convincing costume and the most bad-ass avian haircut. Congratulations Mr. Mourner!


Mimic Octopus

Source: Elias Levy/Wikimedia Commons

Overall Best Costume(s): Mimic Octopus

The mimic octopus can be whatever it wants to be. Observe the mimic in action, with comparison shots of the real animal:

A Flounder:


A lionfish:


Even a sea snake!


Whatever the situation calls for, the mimic octopus can become it. The only constant is its stripes.

Or not…

Full Video

You do you, Mimic Octopus. Or whatever it is you think you are. You win this (and every) year’s Animal Costume Contest.

Happy Halloween from all of us at Greenpeace USA!

By Rachael Prokop

Rachael is an Online Campaigner with Greenpeace USA.

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