Wednesday, February 23, 2011

Deer Survival Strategies

White tailed deer really show off their ability to survive Minnesota's cold winters at this time of year.  If you compare these pictures to the opossum pictures of a few weeks ago you can see why opossums have not been here long. 

Deer fur is thick, and each hair is hollow to add insulating value to keep the deer warm.  The deer has fur right down to the tip of its nose, and its ears are thickly furred. Not like the Opossum's thin furless ears.
Deer also constantly turn their ears to catch all the sounds around them.  Not all of us can turn one ear forward and the other one backward at the same time so no danger can sneak up.
This is my favorite. Look at the long eyelashes on this doe deer.  Especially the really long ones along the bottom of the eye.  Kind of makes Disney exagerations seem too small.  Actually, in the dark when walking through heavy brush these "guard hair" lashes warn of sticks that might injure an eye.

I took these pictures yesterday at Springbrook's wildlife feeders.  You can see these and other deer adaptations everyday at Springbrook.

Sunday, February 13, 2011

Sure Sign of Spring

It may seem early, but the above freezing temps today feel like a sign of spring.  The Goldfinches are way ahead of us, as witnessed by their incoming spring/summer feathers.

These are not the best pictures, but demonstrate how much difference 3 weeks can make in the way a bird looks.

Longer day length is sending a message to the Goldfinch brain, causing it to release hormones that stimulate new feather growth.  By the time spring actually gets here these birds will look completely different, and have new colors ready for the summer nesting season.
I took this picture on January 22, and the top picture today.  I'll take another in 3 more weeks to see how much change has occurred.

Saturday, February 12, 2011

Red Eye Champions-Nocturnal Animals

Animals that are active primarily at night have eyes that are highly adapted with many more visual receptors than our human eyes.  Each receptor requires lots of fresh oxygenated blood to keep it healthy and functioning.

All that fresh oxygenated blood is what makes eyes look red in a camera flash, and nocturnal animals win the prize for the reddest "Red Eye."

This Barred owl was at Springbrook's feeders looking for prey, using its very healthy eyes to search.  I wonder if this is where the term "with blood in his eye" comes from? 
This rabbit was eating at the same feeders a few days ago, but not at the same time.  It's eyes are even bigger than the owl's eyes, and one of the blood veins within the eye can even be seen in this photo. 

In the end, for nocturnal animals, the one with the best red eye wins all the marbles, and the loser is not in the gene pool any longer.

Sunday, February 6, 2011

Red Tail Hawk Becomes Efficient Hunter

 At Springbrook's birdbanding activity this morning the immature Red Tailed Hawk was back looking for food.  He had feasted on another squirrel on Thursday.  This morning he was oblivious of all the people setting up bird traps and sat watching the ground around us as we watched him.

He suddenly focused on the ground near the windows, and as we watched, he dove down on a short tailed shrew within a few feet of the watchers, and flew off with it to a tree nearby. 

Just enough to generate more interest in a larger breakfast.
He stayed in the feeder area all morning as volunteers took birds out of the traps.  Late in the morning he shocked us by flying down and catching a Downy Woodpecker at one of the suet feeders!  What a surprise!  Coopers and Sharp Shins regularly catch songbirds, but large hawks like Red Tails are generally not considered adept enough to catch small woodpeckers in heavily wooded areas of thick brush.  This hawk is breaking all the rules...which is exactly what you have to do to survive sometimes.  I'm sure it was one of our banded Downy Woodpeckers, but we will never know which one as he ate it all except a few wing feathers.