insects

It is the end of May, and we are enjoying watching all the baby birds fledge, from the Barn Swallows, to the Canyon Wrens.  Yes, even the Steller’s Jay babies are cute.  We have a front-row seat with the California Towhee parents, who built their nest at knee height in the geranium bush.  It is amazing how any of these chicks survive.  Of their three eggs, the Towhees lost one egg that rolled out of the nest; one chick was eaten by a Gopher Snake; and we rescued the remaining chick from the snake’s mouth.  And we are still waiting for all the hummers to return and explain where they have been.  We’ll keep you posted. 

 

The evening sunsets are quite beautiful and we are betting each other on how far north the sun will be setting when the summer solstice occurs.  From late April on, the sun sets over Dolan Ridge, so we don’t get to see the green flash now.  Each evening, the sun creeps a little farther north up that ridge.

 

It is this time of day that we see our “magic” bat come out of the eave of the house and begin her quest for bugs.  As we promised, our “bat scientist” was back for a visit and gave us some information about bats that was quite surprising.  There could be as many as fourteen species of bats on the reserve, in the various habitats.  Many of the species are quite adorable, and nothing at all like the Vampire Bat we all imagine, with big teeth and an evil face.

 

Bats may be the most misunderstood animals in the United States.  Almost all U.S. bats feed almost exclusively on insects and are thus extremely beneficial.  One bat can eat between 600 and 1,000 mosquitoes and other insect pests in just one hour.  Bats in other parts of the world feed on a variety of items, such as fruit.  Fruit bats perform an extremely important function as seed dispersers.  Many plants depend almost entirely on bats for pollination.

 

Bats, like humans, are mammals.  They have hair and give birth to living young; and feed their young on milk from mammary glands.  Most female bats produce only one offspring per year, although some species give birth to three or four babies at a time.  Most U.S. baby bats are born in May or June.  The babies develop rapidly and learn to fly within two to five weeks after birth.  They are the only true flying mammals, belonging to the mammalian order Chiroptera, which means “hand-wing”.  The largest U.S. bat, the Greater Mastiff Bat, occurs from central California, south into Mexico, and has a wingspan of almost 22 inches.

 

Bats depend on their superbly developed Echolocation (or sonar) system to navigate in the dark.  They emit pulses of very high-frequency sound (inaudible to the human ears) at a rate of a few to 200 per second.  By listening to the echoes reflected back to them, they can discern objects in their path.  Their echolocation ability is so acute; they can capture tiny flying insects even in complete darkness.

 

We can also dispel one of the more popular myths about bats:  less that ½ of 1% of bats carry the rabies virus.  Fewer than 40 people in the U.S. are known to have contracted rabies from bats during the past 40 years.

 

Why do we call our bat “magic”?  We know she lives in the eave, in a space about a quarter inch wide.  But we never see her enter or emerge.  She just appears out of thin air.

Most likely, she is a California Myotis.  We also believe we have the Big Brown Bat on the reserve.  In a future article we will give you details about the species found in Central California.  In the meantime, you can go to www.norcalbats.org and see pictures of all the local bats.  Some of them are downright cute!

 

Terry Hallock, Kim Glinka and Feynner Arias