Saturday, May 26, 2012

Birds/Warblers and Butterflies at Springbrook

This seems to be the year for butterflies at Springbrook.  I have already seen many more numbers and species than usual.  I saw three individuals of this Ohio Buckeye Butterfly yesterday.  This is the first time in 30 years I have seen this butterfly at Springbrook.   

The Red Spotted Purple butterfly down below was sitting in the access trail/road near the railroad tracks.  It was sipping water/minerals from beneath the rocks, so sat still with its wings open, an unusual sight.
This butterfly is usually flying fast in and around the edges of wooded areas, and is normally hard to get close to. 

This butterfly is closely related to the White Admiral in the post I made earlier this week. The two butterflies can interbreed, making for some odd color combinations in the next generation.
This "after second year" male Mourning Warbler is one we caught at last Sunday's bird banding at Springbrook.  This is one of the late migrants still flying north to find a place to nest for the summer.

This Chestnut Sided Warbler male is one of the prettier warblers we caught in the mist nets last Sunday.  After being measured and weighed, along with having a band placed on his leg, he was released to continue his journey north to find a nesting area.

Firefly Larvae and Pupae Bioluminescence

A few days ago when searching through a rotting stump I found these Firefly larvae and two pupae.  I took this 4 second exposure to capture the bioluminescence in their abdomens.  Any day the adult fireflies, which are a kind of soft winged beetle, will be emerging and flying the low areas adding their allure to late evening hikes at Springbrook and other natural areas. 
 The chemical/pigment luciferin combines with oxygen to cause the glowing "light" in fireflies.  An enzyme called luciferase speeds up the reaction to make them even brighter.  Nature and science combine in ways that make wonderful viewing for us.

Wednesday, May 23, 2012

White Admiral Butterfly Life Cycle

Two weeks ago I was leading a group of 2nd graders around the Beaver Pond trail at Springbrook Nature Center.  We were looking for examples of life cycles in nature.  One of the students noticed this very odd caterpillar feeding on a wild cherry tree leaf.  It was a White Admiral butterfly caterpillar.  These Caterpillars mimic a bird dropping to not get eaten. 
 It does not look like food to me!
Two days later it attached itself to the cherry twig stem and hung up side down preparing to metomorphose into it's chrysalis.  This is the part of it's life cycle where it stays quiet while changing into a butterfly, or the adult portion of its life.

It hung like this for less than 24 hours before its skin split and the new chrysalis underneath was revealed.

Notice the spiracles, or breathing openings, one on each segment of its body. they are little tiny dark "holes" in the center of each segment.
I took this picture within an hour after it shed it's caterpillar skin.  Notice that you can already see the veins in the wings, and the antennae running along the front edge of the wing.

Less than 24 hours before photo was taken this was a caterpillar walking up the leaf on the tree!

It still is trying to look like a bird dropping so nothing will eat it.  It also has this very odd disc sticking out of its back.  Somehow the disc must make it look less like something good to eat, because I don't believe it will be of any use to the future butterfly. 
 Seven days later the skin over the wings has hardened and you can begin to see butterfly forming inside the transparent skin.
 By the 8th day as a chrysalis the color of the scales on the wings  can be seen through the skin.  With each hour the colors are more vivid now. 

The butterfly was ready to emerge at this point.  I waited up until after midnight to try to catch it breaking out of the chrysalis, but finally gave up.
 It must have emerged shortly after I left it, since the chrysalis was empty at 6:30 AM the next morning.  The butterfly was a few inches away on the twig, with wings hardened after several hours of drying
The White Admiral is a good example that you do not have to go to the tropics to see beautiful, colorful butterflies.  They exist right here in Minnesota, and this is one of the most colorful.

Here it is next to the now empty chrysalis.
These pretty butterflys are slightly smaller than Monarch butterflies, and are found in wooded areas where they fly very fast zig-zag patterns amongst the branches of the trees.  They are at Springbrook right now near the park entrance.  But you need quick eyes to see them.

Saturday, May 5, 2012

Cecropia Moth Emerges From Cocoon

Last fall I created a post about the Cecropia moth caterpillars making their protective cocoons to overwinter inside them as pupae.

Yesterday, about 4 pm, an adult moth emerged from its cocoon while I was working nearby, and I was able to set the camera up quickly and photograph the moth as its wings expanded and hardened.

The picture on the left is one I took this morning after the wings had hardened all night and the moth had recovered some energy. The moth's wingspan is 6".
 This is the caterpillar from last fall as it was "spinning" the silk, which comes from its mouth, to make the cocoon.  It was inside the cocoon for just over 7 months.

Down below is the moth about ten minutes after it had emerged.

Moths are emerging daily from their cocoons at Springbrook Nature Center.  Visit the center to see this life cycle end and a new one begin.
 In this picture the moth is already about ten minutes old, and the wings are expanding quickly.

After emerging, the moth hangs from the silk cocoon and pumps fluid from its body into the wings.  The wings are very soft and floppy at this stage, and it is critical for the moth to be able to hang with the wings hanging below it. 
 Within another ten minutes the wings are quickly opening up, with wonderful color concentrations. Within a few minutes these yellow/green spaces had expanded out and were gone.

You can tell this is a female by the small antennae and the large body that holds all the eggs. The males have very large antennae that can smell the female's pheromones for miles.  At night the males fly toward the pheromone smell until they find the female and mate with her.

Cecropia moths, and all moths in the saturniid family, including Luna and Polyphemus moths, emerge as adults without any working mouthparts.  So they are unable to eat anything.  Their purpose as adults is to mate and lay eggs. After a week or so as adult moths they die.

The body colors of the adult Cecropia moth are my choice for the most attractive of all the large moths.
By the end of an hour the wings were nearly fully expanded but still very soft and floppy.  It was getting dark outside and I needed to use a flashlight to light the moth up.

I took the last picture below at about 10 pm.  The wings were finally just drying enough for the moth to hold them out from her body instead of only letting them hang as in the picture to the left. 

Friday, May 4, 2012

Baby Red Foxes at Springbrook

 The baby Red Foxes at Springbrook Nature Center are growing fast.  These pictures from 6 AM on April 23rd show more color and a longer muzzel.  Most of the bluish cast to the eyes is also gone.

There seem to be only two kits, and they dissappear well before the sun comes up.  But early in the dawn light they silently play with mock attacks on each other, and find bits of old animal skin and fiercely shake it, pounce on it and find tiny bits of food to pull off for a snack. 

I've seen one of the adults drop off a freshly killed muskrat and a small rabbit.  But the sound of the shutter makes the adults run off with a warning bark to the kits, who quickly dive into the den.
This little kit saw something alarming in the sky that I could not see from my blind, and an instant later the little fox had bolted into the burrow entrance behind it.
At this age these little foxes are alert and curious.  The other kit dissappeared at the click of the camera shutter, but this one was curious to know where the sound was coming from and walked toward the sound.  The top picture was taken when it had reached its closest point, about 30 feet away. 

It was dark enough that I had to take these pictures with an ISO of 2000, a shutter speed of 40th/sec,  and lighten them in photoshop to make the pictures look ok here.