Tuesday, May 31, 2016

Chihuahuan Raven

Chihuahuan Raven, Corvus cryptoleucus
The Chihuahuan Raven is the size of a crow, but with the shape of a raven, and, as with many birds, vocalization is easiest for distinction. They can be found year round throughout most of Texas, parts of Arizona and New Mexico, and south into Mexico with preference for dry grasslands, arid regions, scrub, and yucca flats. Unlike its Common Raven cousin, the Chihuahuan Raven is more sociable and can often be seen in flocks of up to several hundred during winter. The base of the feathers of the Chihuahuan Raven is also white, unique in North America, but not uncommon in other crows and ravens around the world, and is difficult to see without aid from the wind. Their nest of twigs, often those of thorny mesquite trees, may be reused in subsequent years. The female will lay an average of five eggs and both parents bring food to the hatchlings. Chihuahuan Ravens are omnivorous and will consume anything from insects and grains to carrion and frogs. They can sometimes be found near garbage or landfill, or else sitting on a pole.

Tuesday, May 24, 2016

Hiatus (Week)

Rio Grande chirping frog, Eleutherodactylus cystignathoides
It's another long, busy week so there will be no new posts this week, but they will resume again next week!

Thursday, May 19, 2016

Cloudless Sulfur

Cloudless Sulfur, Phoebis sennae
The Cloudless Sulfur is a common butterfly that can be found throughout the southern half of the United States down as far south as Argentina, but can be found in the West Indies and may reach as far north as southern Ontario. While a permanent resident in the tropical regions, Cloudless Sulfurs do migrate during autumn and spring, going south and north respectively. Unlike Monarchs, Cloudless Sulfurs fly at lower altitudes while migrating. This makes migration easier to observe, especially in autumn when numbers are generally higher, but also make them more vulnerable and likely to be killed crossing roadways. The adults prefer to feed on tubular flowers such as bougainvilla, cardinal flower, hibiscus, lantana, and morning glory, but the host plant for the caterpillars are the Cassia species in the pea family. Cloudless Sulfurs breed in disturbed open areas and many can sometimes be seen drinking from mud puddles.

Tuesday, May 17, 2016

Spiny Orbweaver

Spiny Orbweaver, Gasteracantha cancriformis
Orbweavers, as mentioned before, are found throughout the world and vary in size and appearance, but they are all associated with the classic orb web and, more often than not, it is the female that is larger and more colorful than the male. One such distinct species found throughout most of North America, including some of the islands, is the Spiny Orbweaver, also known as the crab spider, jewel box spider, and smiley face spider. While the colors may include white, orange, yellow, black, or red, the females, about 5-9 mm (0.2-0.35 in) in length and 10-13 mm (0.4-0.5 in) width, all have six pointed abdominal projections referred to as spines. The males, while also with some color variation, are only about 2-3 mm (0.8-0.12 in) in length and lack spines, but may have posterior small humps.

Female spiny orbweaver in the shade of a grapefruit tree.
The spiny orbweaver can be found in woodland edges, nurseries, and gardens, but are also commonly found in citrus groves. The lifespan for this species is short with males dying approximately six days after successful sperm induction to females, and the females die soon after depositing her egg sac of 100 to 260 eggs. When they hatch, the spiderlings will remain in the carefully constructed egg case for 2 to 5 weeks of age. When they leave, they are considered mature. New webs are constructed each night for structural security, always with tufted silk that some studies suggest could be warning flags for birds so they do not fly into the web and destroy it. As with other orbweavers, the spiny orbweaver waits for pray to land in her web in which she will paralyze it and eat it, if smaller than her, but if it is larger, she will wrap it in silk before carrying it to the center to consume. Although their colorful appearance and spines may have an anti-predator function, spiny orbweavers are harmless to humans and are often considered a beneficial species.

Thursday, May 12, 2016

Hooded Oriole

♂ Hooded Oriole, Icterus cucullatus 
The Hooded Oriole is a medium-sized oriole found in the southwestern United States during summer and in western portions of Central America during winter. The bright orange and black of the males gives this bird its common name as the pattern makes it look as though he's wearing a hood. As with many other songbirds, the females and immature males are more drab, an olive yellow with dusky wings for this species. Nests are most often found in palms or large yucca sewn to the underside of a large leaf, but have also been found in moss and mistletoe clumps. They forage on insects, berries, cultivated fruits, and nectar, and are sometimes seen at hummingbird feeders. Although their population is currently stable overall, there is a notable decrease in the Lower Rio Grande population likely due to cowbird nest parasitism.

Tuesday, May 10, 2016

White-veined Dutchman's Pipe

White-veined Dutchman's Pipe, Aristolochia fimbriata
White-veined Dutchman's Pipe is a South American trailing vine that prefers indirect sun to partial shade. It is drought tolerant, evergreen in warmer climates, and blooms from Spring until Autumn. The unique shape of the flowers allows for guaranteed pollination as insects as drawn by the stench into the tube of the flower. In order to escape, the insect must navigate downward pointing hairs which result in a coating of pollen. The growing popularity of White-veined Dutchman's Pipe is its ease of growth and its contribution to the Pipevine Swallowtail population; similar to monarchs, Pipevine Swallowtails feed specifically on Aristolochia spp. for its noxious chemicals which they incorporate into their defense mechanism. The common native species, Woolly Dutchman's Pipe, with thicker leaves better suited to large batches of swallowtail larvae, is not as easily accessibly to home gardeners at this time.

Thursday, May 5, 2016

Rio Grande

View of the Rio Grande River
The Rio Grande begins as a clear, spring and snow-fed mountain stream in Rio Grande National Forest at 3650 m (12,000 ft) above sea level and ends in the Gulf of Mexico. It is the fourth longest river system in the United States, the twenty-second longest river in the world, and is estimated to be roughly 3 million years old. It cuts through New Mexico and becomes an international boundary once it reaches the junction of Chihuahua and Texas, at the site of El Paso and Ciudad Juárez. The recognition of the Rio Grande as an international boundary comes from the Treaty of Guadalupe Hidalgo (1848) which ended the Mexican War, but the issue of the exact boundary was not solved until the banco treaty of 1905. It wasn't until the 19th century that the name Rio Grande for the whole river became the standard in the United States; previously, it was known as the Rio del Norte in the upper portions, and in Mexico, it is still usually known as the Rio Bravo. In 1997, the Rio Grande was designated as one of the American Heritage Rivers.

There is a fair amount of history associated with the Rio Grande, but rather than type it all up, I will simply redirect you to one of the cited links above for a good summary (found here).

Tuesday, May 3, 2016

Whitethorn Acacia

Whitethorn acacia, Acacia constricta
Whitethorn Acacia is a native, multi-trunked tree or shrub found within the desert areas of the southwest that blooms with small, yellow balls of fragrant flowers. It is drought, cold, and heat tolerant tree that can reach 6 m (19.7 ft) in height and live up to 72 years old. Upon a top-kill, such as by fire, whitethorn acacia will sprout from the root crown. It will commonly flower once in spring and once in fall. The short-lived flowers are most often pollinated by honey bees while the seeds are consumed by quail, rats, mice, and occasionally deer. Native Americans would grind the beans into a meal for food, and use the beans, leaves, and roots for digestive, respiratory, and dermal symptoms.