What do moose eat in the winter?

Visitors to the Greater Yellowstone often look at the vast sagebrush and wonder what purpose it serves...other than catching your feet and tripping you on every step. Actually, this ecological community supports a remarkable diversity of wildlife. For example, sage brush flats provide critical winter habitat for moose. Such as the bull moose pictured here browsing on bitterbrush.

Ermine

Catching a glimpse of these little guys is always a treat...one that never lasts long. This is an ermine. Their coat turns from brown to white each winter, allowing them to be nearly invisible as they move through a snow white landscape. Their tail has a black tip on the end, which functions as a decoy luring any potential predators to strike there, rather than a more vulnerable part of the body. 


Bull Bison in Grand Teton

This may be my favorite thing to see in the winter...a big bull bison covered in frost. The winter coat of a bison is so well insulating that there isn’t enough heat escaping their body to melt the frost. I’ve been able to photograph this bull several times over the last couple years. His exceptionally red coat, and the red patch on his face, make him easily recognizable.

Red Fox in Grand Teton

There are few things I find more visually striking than a red fox against the white snow. I found this fox as it was hunting for rodents under the snow. The fox will listen carefully for movement under the snow, turning its head back and forth to pin point the sound before leaping into the air and diving head first into the snow.


Lodgepole Pine

Lodgepole pine dominates the Greater Yellowstone landscape. The drastically varying heights of the trees are a poignant reminder of a powerful force in the ecosystem, that of fire. This remaining stand of trees high above the Madison River has always impressed me. These few trees somehow survived while everything around them burned to the ground. Though we feel a sense of loss after a major burn, fire is not necessarily a bad thing, nor does it get the last say when it comes to these trees.

The lodgepole pine is equipped to respond to fire in a remarkable way. Their secret is found in a condition called serotiny. Now that we got the fancy word out of the way, what does it even mean? Many of the female cones produced by lodgepole pine remain closed, until they are met with the extreme heat of a fire, at which time the cones open and disperse seeds all over the forest floor. This is why you see such a high density of young trees growing in areas that have previously burned. The smaller trees pictured in the foreground here are 30 years old! They have a long way to go before reaching the heights of their forbears.

The lodgepole pine, making up 80% of the Yellowstone forest, is remarkably resilient in its ability to grow in less than ideal conditions. Here, the poor conditions eventually took their toll. The wet and mineral laden sulfuric soil around hydrothermal features is a tough place to survive. 

These trees are known as bobby socks trees because of the white section on the lower trunk which resembles bobby socks. As the trees absorb the water from hydrothermal runoff they also take in minerals. When the water evaporates, the minerals remain and turn the bottom of the trees white.