For many Iowa animals, the stark
landscape – bare trees and a bright white groundcover – makes them stand out
more in the winter, which is good news for those who enjoy watching wildlife.
But for a few Iowa critters, winter is a time for them to blend in with the
scenery.
Jackrabbits
They may have “rabbit” in their
name, but Iowa’s jackrabbits are actually hares, related more to the snowshoe
hare than the cottontail rabbit. Come winter, jackrabbits shed their summer fur
– brownish-gray speckled with brownish black and a white tail – to make way for
their white winter coat. The only coloring left is black on the tips of the
jackrabbit’s ears and a light gray tinge to the ears and back. The changing coat
allows the jackrabbit to hide better in the conditions that different seasons
bring.
What it can’t hide from, however,
is habitat loss and wet weather during nesting seasons. Once widely found in
grasslands in northwestern Iowa and once a common game species, their numbers
have declined in recent years.
Snowy owls
The snowy owl can be a winter visitor in Iowa. It can be difficult to discern the precise reason why any snowy owl may be turning up further south than normal, the reason is usually not to the benefit of the owl. Common reasons for these southern “irruptions” can include shortages of food (lemmings) further north in core wintering areas, or an excess of young birds that are driven from the better northern wintering areas to sub-par locations further south. So if you spot one, it’s a rare sight indeed.
Least weasels
The smallest weasel in Iowa and the
smallest carnivore in the world, the least weasel also has two color phases. It
loses its reddish-brown coloring on its back, sides, tail and top of its head
to get ready for winter, when it may become all white. Spring and fall coloring
are often a mix as the color transition takes place. It’s not likely you’ll see
a least weasel, as they primarily hunt at night and below the snow, but you’ll
occasionally find them caught above a hard-crusted snow. Least weasels are
small guys, rarely growing longer than 10 inches long.
American goldfinch
Iowa’s state bird doesn’t lose
all of its coloring in winter, but if you see one in winter, you’ll notice its
hue is more muted than its usual bright yellow. Most birds sport vibrant colors
in the spring to attract a mate during breeding season. They then molt their
feathers to bring in a more drab coloration for the winter, as their normal
bright coloration would make them more visible to predators.
Trumpeter swans
Trumpeters’ year-round white
coloring does allow them to blend in with the snow – mostly. Their large black
bills and black legs provide enough contrast against the white snow to allow
you to spot them pretty easily.
Activities to use while studying
camouflage:
- Color Crazy- recognize and generalize that wildlife exists in many colors
- Quick Frozen Critters- describe adaptations related to predator and prey relationships, explain the importance of adaptations in these relationships and describe how they limit wildlife populations
- Surprise Terrarium- identify camouflage as an adaptation and describe the importance of adaptations to animals
- Thicket Game- identify examples of adaptation in animals and describe the importance of adaptations
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