Quick Scoop

Reindeer are herbivores with remarkably adaptive diets that shift dramatically between seasons to survive the harsh Arctic environment. During winter, they rely almost exclusively on lichen (commonly called "reindeer moss") as their primary food source, which they dig out from under the snow using their strong hooves. When warmer months arrive, their diet expands to include fresh grasses, herbs, mushrooms, leaves from shrubs and trees like willow and birch, and other nutritious vegetation that helps them build crucial fat reserves for winter survival.

Winter Diet: Survival Through Snow

When winter blankets the Arctic landscape, reindeer face significant challenges in finding food. Their primary sustenance comes from lichen, particularly varieties known as reindeer moss, which provide essential high- carbohydrate energy during the coldest months. Reindeer use their powerful hooves to dig craters through snow to access these hidden lichens, demonstrating remarkable adaptability to their environment.

During winter, reindeer also consume:

  • Various types of moss
  • Fungi found beneath the snow
  • Tree bark when other food sources are scarce
  • Dried vegetation they can uncover

Interestingly, reindeer can survive on this low-protein winter diet through a unique biological adaptation: they recycle urea (normally a waste product) within their digestive system, making use of its nitrogen content. Their metabolism also slows during winter months to conserve energy while living on fewer calories.

Summer Feast: Building Reserves

Summer transforms the reindeer's dining experience from survival mode to abundance. During these warmer months, reindeer become selective browsers, choosing the most nutritious plants and plant parts available. They graze extensively on grasses, sedges, and herbs that are rich in protein and energy, which helps them build the fat reserves critical for winter survival.

Their summer menu includes:

  • Fresh grass shoots and fully grown blades
  • Green leaves from shrubs
  • New growth from larch, willow, and birch trees
  • Wildflowers and various herbs
  • Ferns (selecting the most nutritious varieties)
  • Mushrooms and fungi, particularly sought after in late summer
  • Buds and twigs from trees and shrubs

Domesticated Reindeer: Extra Treats

Domesticated reindeer receive supplementary feeding from herders to maintain nutritional balance throughout the year. Beyond their natural diet, captive or domesticated reindeer can enjoy additional treats that provide variety and nutrition.

These supplemental foods include:

  • Fruits such as apples and bananas
  • Oats and other grains
  • Hay or dried grasses
  • Leafy greens like chard or sprouts
  • Root vegetables including carrots

However, these treats should not replace their primary natural diet, as reindeer have specific nutritional needs adapted to their Arctic environment.

Seasonal Adaptations: Nature's Perfect Design

The reindeer's ability to transition between dramatically different diets showcases their incredible evolutionary adaptations. In late spring and summer when food is plentiful, they consume high-protein, high-energy foods with relatively low fiber content. As autumn approaches, the fiber content of available vegetation increases while protein and energy levels decline, prompting reindeer to gradually shift their feeding habits.

This seasonal eating pattern serves a critical purpose: summer and autumn feeding allows reindeer to gain substantial body weight and build fat reserves that will sustain them through the meager offerings of winter and early spring. Their energy intake and time spent foraging are greater during warmer months than winter, facilitating the positive energy balance needed to survive harsh conditions. Reindeer are instinctually able to identify and select the most nutrient-dense food options available in their environment.

TLDR: Reindeer survive Arctic conditions through seasonal dietary

flexibility—relying on lichen and moss dug from beneath winter snow, then feasting on grasses, herbs, mushrooms, and tree leaves during summer to build fat reserves. Their bodies have adapted to recycle nutrients and slow metabolism during harsh winters when food is scarce.

Information gathered from public forums or data available on the internet and portrayed here.