The Largest Deer That Ever Lived Were 1,500lb Giants

Irish elk
© Dima Moroz/

Written by Emilio Brown

Published: January 3, 2023

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Today’s deer species typically weigh between 200-300 pounds. One of the largest deer that ever lived was a 1,500 lb giant! Its name is the Irish elk, but this large animal is actually a giant deer. Also known as the Irish deer or Giant deer, this species rival moose in both body and antler size. The largest males of this species weigh almost the same as the Alaskan moose. Their enormous antlers are the largest antlers known to man, and their size made the Irish deer one of the largest deer ever.

History and Discoveries of the Irish Elk

The first giant deer remains were discovered in the County Meath bogs in Ireland. They were originally believed to be moose remains. The first scientific description of Irish elk remains was made in 1695. Irish physician Thomas Molyneux identified antlers to be those of an Irish elk. Remains, especially antlers, were very common in Ireland.

While the Irish elk did thrive in Ireland, they were also abundant across Europe and Northern Asia. Multiple cave paintings have been found depicting the enormous horns of the Irish Elk, giving scientists reason to believe this species lived alongside humans for over 10,000 years. Skull remains with pieces removed found in Germany are described as unlikely due to natural causes, suggesting humans once hunted them.

What Did the Irish Elk Look Like?

Largest Deer Ever - Irish Elk

The Irish elk had massive antlers and is believed to have weighed up to 1,500 lbs.

©Daniel Eskridge/

Standing at about 6.5-7 feet tall, the Irish elk was almost double the height of the deer we see today. While this species of deer looks similar to modern deer, their bodies were much more robust. Their antlers were larger than any deer that ever existed. The antlers of the Irish elk would span up to 13 feet and weigh close to 90 pounds. These antlers differ from modern deers with them having a large single sheet that emerges from their head with several tines projecting from the edges.

Females were typically around 15% percent smaller than males and did not possess the antlers males had. It is believed the males used the antlers to mate, much as modern deer do. They would use them for intimidating other males and attracting a female mate. Based on cave paintings found depicting the Irish elk, these deer seemed to have an overall light brown coloration and a dark stripe running down them.  

Diet and Habitat of the Irish Elk 

The most well-preserved specimen found of the Irish Elk came from the peat bogs of Ireland, which is where it gets its name. However, this species had a wide range from the Atlantic Ocean to Lake Baikal in Russia. It seems they did not inhibit the northward range but kept to boreal steppe-woodland environments.   

Teeth still intact in skulls that have been discovered have been observed under a microscope. The scratches and pits found within the teeth show scientists what type of diet the Irish elk had. Like other deer species, the Irish elk ate a mixed herbaceous diet consisting of grasses, tree leaves, and other types of foliage. Due to the large size of this species, the giant deer with an average weight of about 1,300-1,400 lbs would have to consume about 90 lbs of fresh forage daily. 

Evolution and Extinction of the Irish Elk

The Irish Elk belongs to the genus Megaloceros which is an extinct genus of giant deer that once inhabited areas across Eurasia from the Early Pleistocene to the beginning of the Holocene. The largest species of this genus is the Irish elk. While there is still debate on whether or not a partial antler from the Early Pleistocene belongs to the Irish elk, it is generally agreed that the earliest record of this species is from the late Early Pleistocene. The origin of the Irish elk is still unclear but is believed to be from outside western Europe. 

The primary cause for extinction was once believed to be the size of their antlers. Scientists believed that this was a maladaptation causing the giant deer to be easily hunted. The enormous size of the antlers could have also been an issue when adequate nutrition was unavailable. However, research has shown that antler size did decrease through the Late Pleistocene and into the Holocene, meaning it was most likely not the main cause of extinction. 

With current information, it is believed the Irish elk went extinct due to a combination of pressures. Humans hunting these animals and pushing them into areas without adequate foliage most likely cause the female fertility rate to drop by at least half. By the end of the Ice Age, the severe climate and lack of resources likely caused this species to become extinct.

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About the Author

Spiders, snakes, and lizards are my favorite types of animals, and I enjoy keeping some species as pets. I love learning about the various wonders nature has to offer and have been a writer for 5 years. In my spare time, you can find me getting out into nature.

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