Leaves throughout the forest glowed gold against a backdrop of graying sky as I left Ryerson Conservation Area yesterday afternoon. This morning—as I entered the same preserve along the same road—the dark, skeletal branches were completely visible, stripped of their vibrant leaves that now lay in muddied piles on the forest floor.

These days of November mark a change from crisp colors to muted tones, which offer the perfect backdrop for animals to hide using camouflage. Lake County Forest Preserve educators often teach the concept of camouflage during environmental programs, where students hike in search of animal hides and mounts that have been hidden along the trail. Teachers and scout leaders, peruse our variety of school and scout programs to find a great fit for your group this year. Following is a virtual version of our camouflage hike.

The set of pictures below show animals that use simple camouflage to match their surroundings. Most animals, predators and prey alike, have developed natural camouflage to seek food and hide from danger. There are two ways animals can produce their coloration: chemically and physically. Biochromes, microscopic natural pigments in the animal’s body, produce colors chemically, while physically microscopic structures act like mini prisms that reflect and scatter light to achieve specific appearances.

How well can you spot the concealed critters below? (Answers are at the end of the post. Hover the cursor over each answer for a bit more info.)

Did you find all the hidden animals? Look at the bottom of the post for each answer.

Making themselves even harder to detect, some animals’ camouflage changes with the seasons. Shifts in length of daylight and temperature trigger hormonal reactions in some species that cause them to produce different biochromes. For example, right about now in Lake County, Illinois, least and long-tailed weasels (Mustela nivalis and M. frenata, respectively) trade their brown summer coat for a wintry white one to blend in with snow. Take a quiet walk this winter and test your spotting skills.

Answers to virtual camouflage hike: