About the Center
Nature Trail Tour – July, 2006
Take a virtual tour of the Sibley Nature Tour!
[Additional Tours: February, 2006 | April, 2006 | May, 2006]
When a person walks outside on a hot summer afternoon, they find it easy to believe there is nothing alive in the mesquite pastureland. People are only aware of their own misery, the creepy slide of sweat trickling and tickling. It only takes ten minutes before sunburn reddens the skin of the fair skinned. The skin feels like it is baking. A person's feet can feel the 150-degree heat of the surface of the bare soil.
Texas Scholars and Abell-Hanger Legacy volunteer and Lee High School student Rebecca Arevinas and Sibley Executive Director Burr Williams took photo walks on different days and found an amazing number of subjects to photograph.
People that walk the trail are always curious about the holes in the ground along the way. Most kids call them all “snake holes,” but snakes do not dig (they take over an unlucky victim’s residence.) The July virtual trail began as a study of the holes, but much, much more was found!
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A six-foot bullsnake refused to move out of the trail for Burr. He photographed it over and over, until he was "up close and personal." Its shiny scales indicate it had recently shed.
Cotton rat holes are about the right size for a bullsnake. This one still has a rat in it - and the evidence is the mesquite bean at the entrance.
Another cotton rat hole, under the endemic Cory ephedra, has a snake track coming and going from its entrance.
Not far away was fresh snake scat (droppings).
Rebecca noticed the cracking of mud where rainwater had collected.
Burr found the splat of bird scat left by a flying bird.
Solitary bee burrows are often easy to find - especially when a major pollen source is fully in bloom. Some mesquite blossoms were still present - but without digging up the hole we do not know if that was what the bee was collecting.
Whiptail lizards are very active in July. They usually burrow a little closer to a yucca or mesquite than this hole.
Rebecca snuck up on this whiptail. It stayed motionless as she photographed it, but as soon she photographed it, it disappeared under the mesquite. In the foreground the round objects are jackrabbit droppings. Notice the fallen mesquite beans as well.
Under almost every mesquite a rabbit scrape can be found, and they can often be found in the open as well.
This young cottontail was in its scrape, and Rebecca almost did not see it.
This photograph by Rebecca shows how freezing works as a defensive method. A person (or predator) usually focuses on the first object in the line of sight - and unless the person (or predator) has "rabbit" as a "search image" the mind does not register the hidden shape.
Among the animals and birds of the mesquite brushland lotebushes are the most popular hangout. During the hot summer the species provides the densest shade. In late April and early May migrating birds eat the berries, and when it blooms in late May the sticky blooms attract a diverse collection of insects. Skunks dug for beetle grubs under this lote.
Lote is one of two plants in West Texas that bloom in May and set fruit in April, 11 months later. The small discs visible in this photo are the ovaries of the bloom, which will become a red/blue/black berry (it is those colors in order, over time.
Skunks dig under yucca, too. The yucca moth and the yucca skipper (a butterfly) both pupate in the soil under the yucca.
Old yucca root tops are strange features on the ground. When kids are asked to collect something along the trail that is "weird," yucca root tops "top the list" of items selected. Rebecca did a great job in capturing its strangeness.
Skunks are very adroit. They can dig with one foot, or both front feet. Here, a skunk dug with one foot for a buried beetle. Do they hear the emerging beetle from the pupa case? Is there some faint odor that reveals their food?
Rebecca found what may be the den of a young skunk. Skunks are born in late April to late May and begin to live on their own as early as in late July.
Under this lote the pits of doodlebugs (antlions) are noticeable. They prefer to have their pits where rain can not directly impact the crater, and they like very fine and powdery sand. Since quail and cactus wrens take dust baths under lotes, the soil does become powdery.
Ants are the major food source for horny toads. Near a harvester ant mound the large horny toad chased the smaller one.
When a horny toad stands up on its legs and inflates its body it is in a "bluff posture."
Harvester ants clear the ground near their nest. The ground near the hole is speckled with tiny bits of caliche brought up from several feet below the surface.
The entrances to a harvester ant are small - pencil sized.
Fallen mesquite beans are processed by the harvester ants.
When harvester ants are busy, several hundred are working outside of the nest. When a food source develops at a distance from the hole, little highways are cleared.
Aphanogaster (also known as Novomessor, depending on how old an identification book is being used) ants are the janitors of the pasture (they pick up or pick at everything on the ground.) They have no stinger and can not bite with any force. The prejudice and dislike that is the result of ignorance led a kid to ram a stick in this nest.
Kids call the Aphanogaster ants spider ants (because of their long legs.) The spider ant often design their hole so that they have to enter by walking upside down on the ceiling of the "entry cavern." This must deter some potential predators.
There is often a guard spider ant at the entry hole.
Notice the ant down in the hole.
Some sort of message must have been delivered and acted upon, for a line of spider ants came out of the hole.
Rebecca found one spider ant was carrying another. A person's first guess at the behavior would possibly be that the ant being carried was dead. Some researchers believe that the ant is being carried is actually "resting."
The two dark areas are the entry holes for this nest. In front of the nest is the seed dump. After the seeds are processed the dry husks are carried outside.
Upon close examination, the spider ant seed dump reveals more detail. Did the ants eat the beetle grub that was in the mesquite bean?
Most people think west Texas is full of cactus. On the Sibley Nature Center property only one prickly pear has been found, and only Rebecca knows where it is!
Lace cactus is somewhat common on the Sibley Nature Center property, but is often hard to find because it usually grows where it is hidden by a mesquite, but Rebecca found this one in the open.
Tasajillo is under almost every mesquite. Also known as Christmas Cholla, this cactus has red berries for months. Rebecca found one covered with green berries.
In July 2006 many visitors on the trail reported seeing a tiny gray bird with a yellow cap fussing at them as they walked. Verdins are interesting birds. They build winter nests (the only species besides cactus wrens that do so in West Texas). This is an old winter nest in a tasajillo.
Red mesquite beans are sweet. A number of kids report the taste to be similar to apple juice. Rebecca's photo shows beans beginning to fade to yellow, and when they are completely yellow, they fall to the ground.
If a person examines a mesquite trunk closely, a yellow lichen is often found.
She also notice a curled up green mesquite bean. On the same day as her photo sessions, several kids came in off of the trail wearing "rings" - they had found many such beans. When Rebecca examined the photo she notice the small Crematogaster ants - one on the left side and one in the circle. When she showed them to me, I noticed the leafhoppers. The ants "milk" honeydew (waste products) for food from the leafhoppers (the tiny bumps on the bean.) The ant on the left is in the act of doing so, and several other leafhoppers can be seen in the "ring."
Rebecca found a bumblebee on a Texas Thistlee.
Most robberflies (a major insect predator in the mesquite thicket) look completely different than this one which is a mimic of a bumblebee.
Rebecca noticed this tiny "skipper" sitting on a old wildflower seed stalk. How in the world did she see it?
Some species of dragonflies sit with their tail upraised. They will wander far from water to hunt insects. Rebecca snuck up on this one and got a photo before it flew. Burr was not sure of its identification.
Burr also found one. It is probably a female "red saddlebags."
Although sometimes it seems like there is nothing along the trail until the pond is reached, this photoessay shows what can be found in the mesquite pasture. Both photographers did spend a little bit of time at the pond. Rebecca was amazed at all the ripples caused by the gambusia (mosquitofish) at the pond.
She also found the grackles. Here one is flying towards the pond over the Siberian Elm trees.
The grackles love to perch in the cottonwoods, as Rebecca noticed.
She also found a mockingbird running on the ground.
A hummingbird was also in the grove of trees at the pond. In the foreground are hackberry leaves and berries.
Salt cedar blooms are pretty, so a person can see why the plant was brought from Europe as an ornamental for the garden. They "escaped" cultivation, however, and became a pest, lining playas, draws, creeks, and rivers throughout the American southwest.
Each salt cedar produces millions of seeds.
In July the bloom stalks of cattails begin to shoot up (and they produce millions of seeds, too.)
Damselflies are common at the pond, but Burr has not learned damselfly identification yet. Maybe someone can help us out!
Notice that this Roseate Skimmer dragonfly has its middle legs behind its head. Surprisingly, this is a common posture for a number of dragonfly species.
How can such thin, transparent wings last and be so strong?