Due to its three climate zones, Big Bend National Park, Texas, USA has an amazing diversity of wildlife.

It is known as one of the best places to observe birds, and many species that are native to Mexico can be seen. The birds are active during the daylight hours, feeding mostly on insects, snakes, and lizards, which are also active during the day. Animals such as deer, javelinas and rabbits are found throughout the Park, but come out mostly at night. Mountain lions and coyotes live in the mountains, but are rarely seen. They are nocturnal, as is their prey. Black bears also live in the mountains.

While the Chisos Mountains are pleasantly cool, and the banks of the Rio Grande river are humid, the greatest variety of plant life is in the desert. From a distance the desert can appear lush and green, especially the slopes around the Chisos Mountain range. It comes as quite a shock when you begin to hike across this landscape. What look like trees and grass turn out to be clumps of lechugilla, cactus, creosote bushes, and the occasional ocotillo plant. The desert is a hard place to survive in, but the plants are very good at surviving.

The Wildlife of Big Bend

Spotting some wildlife is pretty easy. Make sure you're awake in the early morning, or in the evening after sunset. Deer, javelinas and coyotes are regular visitors to campgrounds. After dark, properly dispose of your trash, or a skunk may brazenly saunter through your camp, sniffing for edibles, dragging out food wrappers from your trash bag, and generally making a nuisance of itself.

Birds

Big Bend has over 450 species of birds that regularly visit the Park, more than any other National Park in the US.

• Colima warblers are among the better-known visitors. They prefer the higher elevations of the Chisos Basin.
• Hummingbirds, flycatchers, and even golden eagles can be spotted in the Chisos.
• Peregrine falcons nest on Casa Grande, a peak that overlooks the Basin.
• Roadrunners, cactus wrens, orioles, woodpeckers, and many more birds can be seen in the grasslands and Chihuahuan desert regions.
• Doves, vireos, cardinals, painted buntings, vermilion flycatchers, owls, and on occasion even turkeys are spotted by bird watchers in the Rio Grande Valley, close to the river.

The most common birds in Big Bend National Park are the vultures. Whether having their lunch on the road, or turning slow circles above the desert, they are a familiar sight. We may find vultures repugnant, but they are uniquely suited to their role in the environment. Their bald heads prevent infestation from parasites. They feed chiefly on carrion, and their digestive systems are designed to kill bacteria. When threatened, they either fall over and 'play dead', or regurgitate their last meal in the hope of scaring off predators. They will also do this when hit by a car, so use caution when driving through the Park. In the air they look like eagles because of their enormous size, but the tips of their wings are usually a bit ragged, and they hold their wings in a dihedral or 'V' pattern.

Bears

Mexican black bears were once common in the Big Bend area, but hunting and trapping, changes in habitat, and control efforts by the government almost eliminated the bears from the Park. Then in the 1980s they began to migrate back to the Park, though nobody knows why, because wild animals will almost never return to an area that they have deemed unsuitable.

Black bears eat berries, acorns and pine nuts, as well as the fruit of the prickly pear. Like all wild animals in the Big Bend region, they drink water from springs and tinajas. (A tinaja is a cavity in the rock which collects water. Some are quite deep, and have slippery sides. Animals are sometimes found drowned in these pools, and the water is not safe for humans to drink.)

Because the natural balance which allows bears to live in the Big Bend area is so fragile, measures have been taken to ensure that humans do not interfere with the bears. All camping areas have bear-proof boxes, which are steel boxes with latches. At night all food is to be placed in the bear-proof box or in the camper's vehicle. This is for the sake of the bears as much as the humans. Bears that know that humans have food and will seek them out. This damages the bears' own survival abilities when human food isn't available.

If you see a bear, remain calm. Try to keep a safe distance between you and the bear (approximately 100 yards). If the bear approaches you, make loud noises and throw sticks and stones at it. Do not under any circumstances try to feed the bear or approach it. Bears and their cubs may look cute and cuddly, but they are wild animals, and will behave accordingly.

Javelinas

Javelinas are probably among the animals best suited to living in Big Bend National Park. They will eat almost anything, including the pads of the prickly pear, spines and all. Javelinas are often called wild pigs, but are more closely related to wild goats. They can be seen in the Chisos Basin campground in the early morning, looking for tasty tidbits left behind by careless campers.

Mountain Lions

Mountain lions avoid areas frequented by humans. There have been over 2,000 sightings of mountain lions in the Park since the 1950s, but only three humans have been attacked by a lion. None of the injuries was fatal, and the lions were killed by the National Park Service. The Park requests that humans do not seek out encounters with mountain lions, as this is an unnatural conflict that damages the lions' habitat as well as endangering the human.

Mountain lions prey upon deer and javelinas, among other herbivores, and play an important part in limiting their population. Without a predator in the Park, other animals would multiply and quickly exhaust the available food supply.

If you see a mountain lion, remain calm. Don't run, because this resembles the activity of prey. Stand where you are, wave your hands in the air, and shout. If the lion acts aggressively, throw rocks. Your object is to convince the lion that you are not prey, and may be dangerous yourself. If there are children with you, pick them up so that they will appear bigger than they are. Report any lion sightings to a ranger, including date, time, and location.

Coyotes

Coyotes live in the desert and mountain regions of the Park, and prey upon rabbits, lizards and other small animals. Visitors to the Park will rarely see a coyote, but their call can be heard at night, and their tracks and scat can be seen at watering holes.

Scat, or droppings, is a biologist's term for animal excrement. Scatologists are specialists in the study of excrement, and obtain important information from it. They can find bones, bits of fur, or maybe undigested berries that provide good clues to what and how well the coyote has been eating.

If you are camping in the Chisos Basin, watch for coyotes in the early morning, while enjoying some camp coffee.

Tarantulas

The myth surrounding tarantulas has been greatly exaggerated. Tarantulas are large hairy spiders, but their bite is not poisonous to humans. They are not aggressive, and actually make great pets. The best time to see a tarantula in Big Bend is early September through November, which is the mating season.

Rattlesnakes

Rattlesnakes are probably one of the best-known snakes of the western United States. They are known for the distinctive buzzing sound they make by shaking their tails. There are several varieties, but the Red Diamondback and Speckled varieties are the most common in the Big Bend area. Their diet consists of rodents and other small mammals.

The rattle at the end of the tail is created when the snake sheds its skin: a scaly button holds a remnant of old skin in place at the tip, which dries and makes a noise when shaken. The idea that you can tell a snake's age by counting the number of rattles is false. Rattles often break and fall off, and a mature snake will not have more than eight or ten rattles at the end of its tail.

The chances of your seeing a rattlesnake are very small, and the chances of being bitten by one are even smaller. Rattlesnakes use their rattle as a warning, so if you hear that unmistakable sound, be alert, don't panic, and leave the area quietly.

Plants of the Chihuahuan Desert

The Chihuahuan desert is distinctive because of its extensive grassland, more so than any other North American desert. Before humans began to raise cattle in Big Bend, the desert was covered with grasses. Some of the grasslands have been destroyed by over-grazing. When the grass was eaten, it left pockets of rich dirt for other plants to grow in. With replanting, some of those grasslands have begun to return, but it will take many years before the damage done by over-grazing is repaired.

Because of the relatively rich soil, the Chihuahuan desert has an amazing variety of plants, including over 60 species of cactus.

Agave

The agave was one of the most important plants to the many Native American tribes in the area. It was a source of food, and provided fibre for ropes and sandals. A succulent, its waxy leaves have a blue-green sheen. It takes about 20 to 30 years for the plant to reach maturity. Today it is fermented for tequila, made from the heart of the agave.

Yucca and sotol, members of the agave family, are most common in the areas of the lower desert, where there is little rainfall. Their leaves are green, thin and sharp-edged, and shoot from the central trunk like a pineapple's. The trunk is hairy. Yucca and sotol flower in summer, the white petals blooming in profusion from a central stalk.

The lechugilla, another member of the agave family, looks like a bunch of green bananas. Its leaves are similar to a yucca's, but curved, each with a spine at the tip. The juice of the agave lechugilla is poisonous - Native Americans used it to poison their arrowheads. This is one of the reasons hikers are advised to wear jeans in the desert. A scratch won't kill you, but it can certainly sting.

The century plant, also called the desert agave, is a well-known native of the area. It is said to blossom only once in 100 years, but it actually blooms about every 20 to 30 years. The blossoming heralds the end of its lifespan. A stalk grows from the plant, and takes about a week to grow fifteen feet. It then blooms, is pollinated, goes to seed, and dies.

Ocotillo

One of the odder-looking desert plants, the ocotillo sprouts from the desert floor like hairs from a wart. When it is dry the ocotillo bush appears dead, but any rainfall causes the bush to sprout a wealth of green leaves, which hide the sharp spines all along the branches.

Creosote

The creosote bush is one of the newcomers to the Big Bend area. Over-grazing removed competition to the invasion of creosote bushes, and now they are everywhere. Their leaves, when crushed, exude an odour of paraffin.

Candelilla

Many desert plants have evolved waxy coatings to prevent water loss: the candelilla bush is one of these. Looking like a stand of long green pencils, the bush grows on the limestone flats of the Chihuahua desert. While harvesting candelilla is forbidden in a National Park, these plants are farmed in Mexico and then thrown into a vat of hot water to extract the high-quality wax.

Prickly Pear Cactus

Prickly pear cactus grows in the Great Basin, Mojave, Sonoran and Chihuahuan deserts. Its pads are round and flat, and each pad is covered with spines. What makes the prickly pear distinctive is the cluster of almost invisible yellow-red spines called glochids, above each cluster of larger spines. They detach easily from the pads, and because they are barbed they are very difficult to remove. Some prickly pear cactus lack the large white spines, and these are known as spineless cacti, but all have the glochids.

The spineless cacti are also known as blind prickly pear. Ranchers would take the pads of cactus, burn off the spines, and feed them to the cattle. The problem with this was that livestock can't distinguish between treated cactus pads and spineless prickly pear. Cows attempting to take a bite from a spineless cactus would be blinded by the small glochids.

Humans eat the prickly pear in different ways: the fruit can be peeled and eaten, and the pads can be peeled and pickled. Desperate and thirsty hikers in the desert can take a prickly pear pad, peel it, and chew it for the water in the pad, which is alkaline and bitter.

Cholla Cactus

Another regular sight in Big Bend is the cholla cactus. Unlike the prickly pear, it has round jointed stems, ridged along their length. The cholla cactus is a much spinier plant than the prickly pear. Its spines are covered in a thin papery substance which helps prevent water loss. Common varieties are the teddy bear cholla, whose rounded stems resemble the arms and legs of a teddy bear, the Christmas cholla, which bears red berries, and the cane cholla, which can grow up to eight feet tall.

Taking A Hike

While many of these plants and animals can be seen around your campsite, the best and most unusual species can only be found out in the desert, in the mountains, or even down a canyon and under a rock. Experience Big Bend on foot, and you won't be disappointed.