Six short rephrases
The Arctic fox has a dark summer fur that blends with rocks and dirt.
Its dark summer coat hides against the rocks and soil.
In summer, the fox’s dark fur blends with the ground and stones.
The fox’s dark coat hides on the rocky, dusty ground.
Dark fur in summer helps the Arctic fox melt into the rocks and soil.
By summer, its dark fur is easy to miss on rough ground and soil.