Disappearing River

Colorado River- Nat. Geographic

By now I am sure that we all are familiar with the effects of draw down on the Colorado river.  Much like the economy of Greece, the neighboring states are learning that you can't pull out 110% of the water in a river.

A new map on the National Geographic web page diagrams where the water goes in a dramatic fashion.  The map is worth a look.  Click on the Zoomable Map button in the right upper corner of the National Geographic page with the map.

Southern Caterpillar Visitor

Buck Moth Caterpillar

I received this interesting story from Dr. Tom Riley PhD. who is a retired Professor of Entomology from Louisiana State University.  This is posted in his very words.


"Last week I found this 2 1/2 inch-long caterpillar crawling across a path in Cedar Creek, Missouri.  At first I wasn’t sure what it was, however it looked familiar to me.  I knew it was the larva of a Saturniid or silk moth.  It looked similar to an Io Moth caterpillar in shape, size, and spine configuration but the color was totally different.  Then I realized I had seen many of these before in Louisiana and that it had to be the larva of the Buck Moth, Hemileuca maia.     http://bugguide.net/node/view/471

When I lived in Baton Rouge Louisiana these were very common every spring.  I knew they occurred in the Missouri Ozarks, but have never seen any since moving here 8 years ago.

Male Buckmoth- wikimedia

This caterpillar/moth is an unusual find in Missouri, and it also has an unusual life cycle.  The black and white moths emerge in October and November and can be seen flying about on sunny days, even when there is frost on the ground and the temperature is around freezing!

The moths do not feed.  Their role is to mate and lay eggs.   They do this on oak trees, producing a mass of eggs that encircles a small twig.  The eggs are the over-wintering stage for the buck moth.   Once spring arrives, the warmer temperatures and increasing day length stimulate the eggs to hatch in synchrony with the growth of spring foliage on the oaks.  The larvae feed communally until they reach the third instar after which they disperse to feed as solitary caterpillars.   When full grown, the caterpillars crawl down from the tree and pupate in the soil and leaf litter.  This is how I found the caterpillar in my photos.  When I put it in a container with some soil, it immediately burrowed in and pupated.

I will have to wait and see if it survives until fall.  In Louisiana many of the caterpillars I tried to rear were parasitized by Tachinid Flies.

If you find one of these wandering, dark colored, spiny caterpillars, handle it with care as the small yellow-orange spines running down their back can give you a painful sting.  In Louisiana the caterpillars were common every spring and very well known as “Stinging caterpillars”.

I was told that the name Buck Moth came about from the moths being on the wing during deer = buck season. 

In the south the caterpillars eat the foliage of Live Oaks.  Here, according to the Heitzmans, in Butterflies and Moths of Missouri, they are associated with Scrub Oaks in the Ozarks region of Missouri."

^{http://en.wikipedia.org/wiki/Buck_Moth} 

Anatomy of a Snake Bite

How to get bitten by a Copperhead

Copperhead- click to enlarge

We had a Copperhead bite incident on Bull Creek this weekend.  After watching a Northern Water Snake swimming round in our swimming hole many times over the years including several hours the day before, one of our guests felt comfortable with identifying it.

Just as they were leaving from a weekend visit today, a snake swam across the water and crawled out on the solid rock shelf near where they were standing.  Our guest decided to catch this "Water Snake" and grabbed it by the tail first.  The snake tried desperately to escape the grip including crawling between the man's legs and over his sneakers.

Fang puncture sites

Eventually he grabbed the snake two inches behind its head.  In a split second, the snake flipped its head around and bit him twice, one on the index finger's second knuckle and one on the web of the thumb.  He dropped the snake and immediately commented that it hurt a lot more than a "normal snake bite" (comparing it to past bites by a rat snake and garter snakes.)

Within a minute he was having severe throbbing pain in the hand which was swelling rapidly.  He wasn't able to ID the snake from pictures in Amphibians and Reptiles of Missouri.*   His buddy then got the camera and showed me the picture above, an easy diagnosis.

In the Emergency Room, it took two shots of morphine to begin to touch the pain.  Within a few hours his arm was tightly swollen up to the shoulder.  After the administration of anti-venom, he was watched in the ICU overnight as anaphylactic type reactions to it are common and can be quite severe.  He is still requiring morphine 48 hours later.  You can see the snake bite in this Youtube video.

Venomous snakes do not want to waste their precious venom on large bipeds.  They probably want to reserve it for small mammals that will fit in their mouths after paralyzing them with their venom.  Like most animals, they bite larger mammals only in defense.

Studies have shown risk factors for snake bite include male gender, intentional snake handling and alcohol.  Virtually all snake bites occur from contacting a snake, either deliberately or by stepping on or near it.

New 2016 Study
This study in Wilderness and Environmental Medicine found that 68% of the 332 bites reported were found to be legitimate, meaning the victim was unaware of the snake's presence.

Missouri Conservationist, May 1999 issue had detailed information on copperheads.
Enature.com has general snake information.
surviveoutdoors.com has information on first aid. 
Amphibians and Reptiles of Missouri - Tom Johnson

Tale of a Tail

Juvenile Five-lined Skink

If you ever have tried to catch a five-lined skink, you probably have found that all you get is the tail.  Many of our native lizards have tails that break off easily and most will regenerate a tail, although seldom as long as the original.  

There must be  biological advantage to having a tail to justify the energy expended in regeneration.  It turns out that individuals with tails can run faster than those without tails. The lizards tail also stores fat at the base, a backup supply of energy.  Some lizards fight for dominance of their territory and may lose stature in their territory if they lose their tail.

The loss of the tail has no immediate impact on our common lizard's survival.  According to Dr. Craig Guyer at Auburn.edu, losing their tail is a defensive adaptation. 

"There are two ways that lizards lose their tails. In all lizards around Auburn, the tail bones have central regions that break easily when the tail is pulled. The muscles of the tail pull apart easily and the blood vessels constrict to stop the wounded tail from bleeding. So, if a predator attacks a local lizard, the tail is designed to separate from the body, allowing the lizard to escape while the predator eats the tail. 

In species like Broad-headed Skinks, the tail is brightly colored (blue in this case) and is frequently twitched by the lizard so that predators see and attack the tail but not the body. Lizards that lose their tails in this way can grow them back but the replacement tail is never as long as nor as colorful as the original one. Replacement tails grow back in as little as three months or as long as two years."

Large lizards lack this defensive adaptation and do not regenerate their tails if they are bitten off. To date, no one know how the regeneration occurs. Imagine the ramifications to treating human injuries if we understood this. One more reason why all "all God's creatures got a place in the choir."

An extended discussion of autotomy (self-amputation) is at http://en.wikipedia.org/wiki/Autotomy

Vultures

Watching its sibling break out

Big news on Bull Creek- twins!  Well not exactly but the two vulture eggs in May's blog have hatched 34 days after we found them with Chris and Deb Barnhart.  When we checked the eggs Sunday, one had hatched and was watching the other egg carefully as its "twin's" beak was just showing up in the crack.

Mom and chick

This morning they were hanging out together, looking like a couple of cotton balls with tiny black beaks.  This afternoon, they were nestled in beside mom.  (Click pictures to enlarge)


When we first found them, any approach to the barn stall alarmed the parent who would fly out to the corral railing, then take off.  Last week they would just sit on the railing and watch us.  Now mom didn't blink an eye as I took pictures through the slats of the stall, even when I used the flash.  Maybe we will be their godparents!

Play time

One of the chicks resembles Charley of Audubon fame, only with more hair (feathers).  We decided to name them Na and Megan in honor of our graduate student friends who were with us the day we found the eggs.

Proud Parents

A set of pictures is on this Picasa site.
More on black vultures from a previous blog.

Broad-headed Skink

Click to enlarge

Catching butterflies for the Butterfly House, I saw a bright orange spot in a pile of flood debris.  I expected a Great Spangled Fritillary but instead found a Broad-headed Skink, (Eumeces laticeps).

Like skinks in general, Broad-heads tend to sun themselves on logs, downed timber and dilapidated buildings.  They are the most arboreal (tree climbing) of lizards and may even sleep in trees at times.  They eat insects and spiders and in turn get eaten by snakes, hawks, skunks, larger lizards and even armadillo.

Juvenile Five-lined Skink

The Broad-head name comes from their large jaws which give their head a triangular shape.  Males are usually an olive brown color with smooth scales and minimal or no lines.  Females have five lines down their body and can be confused with five-lined skinks.  This is particularly true with juveniles as both species are striped and have bright blue tails.  These tails are thought to ward off attacks from aggressive males of the species and to entice predators to strike the disposable tail (more on this next week).

Why the orange head?  In breeding season, the males develop their bright orange color, presumably as a way of attracting females.  They fight other males aggressively for the attention of the largest females which tend to lay the most eggs.  Like all other species except a biped, it is all about creating the most progeny.

A series of pictures are at herpsofarkansas.com.

How Mosquitoes Smell You

Wikimedia

Mosquitoes had been thriving on Bull Creek as frequent rains left lots of little breeding spots.  While they use their piercing mouths to obtain nectar and plant juices, the adult female needs just a little of blood before she can produce eggs.  Some species like my blood.

How do they find me up on the deck?  They use specialized maxillary palps near their mouths to sense carbon dioxide, then hone in on the source.  Since holding my breath outside isn't an option, we are left with chemical repellents.  Citronella candles are effective if you are close to their smoke.  A variety of folk remedies and natural compounds may help but aren't as effective as DEET.  Treating clothes with permethrin is effective and withstands multiple washings and some clothes come pretreated.

New research in the Journal Nature describes three types of new chemicals that can confuse those same sensory palps that are looking for carbon dioxide.  They were discovered while studying fruit flies which also seek out carbon dioxide, in this case produced by ripe fruit.  Some of these fruits have developed chemicals which block those receptors.  Studying these molecules with mosquitoes, Anandasankar Ray, of the University of California, Riverside, says  they seem to work three different ways.  Quoting from a story on livescience.com,

1. The first group works by binding to the mosquitoes' carbon dioxide receptors in the maxillary palps, stopping the mosquitoes from sending the signal indicating there's a mammal close by when they sense carbon dioxide.
2. The second group of molecules acts to mimic carbon dioxide's effect on the mosquito — they turn on the carbon dioxide sensing neurons and essentially overwhelm them.
3. Another group of odor molecules essentially blinds the mosquito to any nearby blood-filled humans by disabling their carbon dioxide-detection machinery. Even a brief exposure to these molecules was enough to confuse the mosquitoes' carbon-dioxide detectors for minutes and severely reduced their sensitivity for minutes afterward.

They found the maximum effect was achieved by mixing the different chemicals.  With this mixture the mosquitoes couldn't find the carbon dioxide trail either in the lab or in the field.   Human studies are underway.  Someday we may not have to apply the oily DEET mixtures.