#bestcarcass dead animal photos you cannot unsee (GRAPHIC IMAGES)

In January 2017, a peculiar hashtag -- #bestcarcass -- started trending on Twitter, inviting biologists to enter an informal online competition for the most compelling animal carcass photo.

The biologists didn’t hold back, and soon, nonscientists joined the hashtag trend as well.

Warning: The images in this gallery are graphic in nature.

This porcupine was entombed in ice in Canada. 

Frozen fish

Cold conditions killed these fish. When the temperature dropped even more, the iced-over waters of the Lake Andes National Wildlife Refuge buckled, according to the U.S. Fish & Wildlife Service.

Wasp

This is the head of a yellowjacket wasp.

Raccoon

This raccoon was frozen in a pipe.

Carcass in Casper

This frozen creature was photographed in Casper, Wyoming.

Impala in a tree

This impala carcass was discovered in a tree in Botswana.

Alligator

This alligator carcass was spotted in the St. Johns River in Florida.

Sea creature

This dead creature, apparently a squid, was spotted on Juno Beach in Florida.

Seabird

This seabird got caught in the trees.

Toothy fish

This fish head was discovered on a Florida beach, according to the photographer.

Snow-covered

A snow-covered carcass in Kentucky. 

Moth

This beautiful carcass is that of a chrysiridia rhipheus moth, according to the photographer.

Snowshoe hare

This deceased snowshoe hare was found at Mount St. Helens in Washington state.

Field cricket

This dead cricket was in a strange position.

Frozen fox

This fox was frozen in ice in Fridingen, Germany. Johannes Stehle, a local hunter and hotel owner, said the animal fell into the chilly Danube river and drowned. Stehle said he’s seen deer and wild boar meet the same fate.

Sea slug

This was a blue glaucus, a type of sea slug, according to the photographer.

Snapping turtle

A photographer captured this image of a dead snapping turtle near the Tombigbee River in Alabama.

Moorish idol fish

This dead Moorish idol fish was photographed in Hilo, Hawaii.

Cormorant

This cormorant got tangled in fishing line and died, according to the photographer.

Seal

This is a seal that washed up on a beach in Nova Scotia, according to the photographer. 

Viperfish

These are viperfish from the deep sea, according to the photographer. 

Squirrel

The photographer believes this squirrel was likely electrocuted.

Colorful bird

This colorful deceased bird was found in Australia, the photographer said.

Gizzard shad carcass

The garter snake is living. The gizzard shad fish is not.

Crane carcass

This is a deceased brolga, a member of the crane family.

Mountain goat

These are the remnants of a mountain goat carcass, according to the photographer.

Bird head

This unidentified bird was discovered without a body.

Sea urchin

This urchin was preserved from a deep-water oceanic basin.