One of the neat things about living in Colorado is the ability to see all kinds of lizards in their natural habitat. Lizards are a type of reptile – reptiles also include snakes, crocodiles and alligators, and turtles. Lizards are classified in the phylum Chordata, subphylum Vertebrata, class Reptilia, order Squamata, suborder Sauria. Lizards typically have dry, scaly skin, four feet, claws and a long tail. They can be found in various habitats, including trees (arboreal), underground (fossorial), on the ground (terrestrial), and even sometimes in water (aquatic). Most female lizards lay eggs, although some bear live young. It used to be thought that there were only 2 venomous species of lizard – the Gila monster and the Mexican beaded lizard. Both are found in the Sonoran desert. However, not that long ago scientists discovered that monitor lizards (including Komodo dragons) and some in the Suborder iguania (including some iguanas) have mouth glands that secrete venom.
There are over 3,000 species of lizard in the world, and they are found everywhere except the arctic and Antarctic. Lizards are often fast runners, and some can run up to 15 miles per hour!
Colorado has 19 species of lizards, and most are generally found under 8,000 feet of elevation. This is due to the fact that they are cold-blooded (also called ectothermic), meaning that their body temperature is typically the same as the temperature of their immediate environment. For this reason, you will often find them sunning themselves on a warm rock when the air temperature is cool, and conversely hiding in a cool hole when the air temperature is hot.
Lizards use their tongue to find odors, as snakes do. They are closely related to snakes, but lizards generally have legs, ear openings and eyelids. Lizards have small teeth to bite their prey. Most lizard bites in Colorado will feel like a pinch, although the bite of the Eastern collared lizard may cause some bleeding. Lizard prey usually includes insects and spiders, and lizards can often help in controlling pest species. They may also sometimes eat mice, and smaller lizards.
One interesting adaptation of lizards is that they will lose their tail when it is grabbed by a predator. The predator is left with a squirming tail (the muscles in the tail continue to contract for a while), while the lizard runs and hides. A new tail will grow back, but it may take several months, and a lot of the lizard’s energy. For that reason, we should never try to make a lizard lose its tail on purpose!
Although lizards may all look the same to some people, they often have distinct features that help to identify them. Lizards in Colorado range from the Eastern collared lizard to the diploid checkered whiptail, to the Roundtail horned lizard, to the Many-lined skink. Skinks generally look like a ‘true’ lizard, but have almost no neck, and shortened limbs. Horned lizards are often incorrectly called horned toads because of the shape of their short, squat bodies. Their ‘horns’ are actually spines found on the back of the head. Some whiptail species are one of the few species of animal that can reproduce asexually – females lay eggs that develop without fertilization. Essentially, the whiptail lizard clones itself. The checkered whiptail in Colorado can be either diploid (having two sets of chromosomes) or triploid (having 3 sets of chromosomes).
A couple of Colorado Lizards…
In our part of the state, the Eastern collared lizard is one of the most common, and easily identified lizards, especially during mating season. During this time, males change to bright colors of yellow, blue and green. They can also be brown, and have various patterns of spots and dark bands. During mating season the males especially may be easy to spot, as they display themselves on top of a rock or log. The collared lizard gets its name from the 2 black bands on its neck that are usually separated at the nape of the neck. Collared lizards may eat anything from grasshoppers and spiders, to smaller lizards and snakes. They are preyed upon by hawks and large snakes. When trying to escape a predator, they have been seen to run away on only their hind feet!
Longnose Leopard Lizard
If you haven’t heard of the longnose leopard lizard before, you are probably not alone. Although they can be very common in the Great Basin of Nevada and Utah, the longnose leopard lizard is only found in a few distinct places in western Colorado, one of which happens to be Canyons of the Ancients National Monument (CANM), west of Cortez. In fact, this species is considered to be a sensitive species by the Bureau of Land Management (BLM), meaning that it is a species that could have some risk of becoming endangered.
Not much is known about the longnose leopard lizard in Colorado. Geoffrey Hammerson, author of Amphibians and Reptiles in Colorado, states in his book that longnose leopard lizards only appear above ground for a short period during the year – from late May to early August, and are most active from 2-6 hours after sunrise. Otherwise they are either hibernating while it is cold, or aestivating, staying underground while it is extremely hot. One thing getting them above ground is the opportunity to mate, and females will usually produce between 6-10 eggs every year. Longnose leopard lizards probably used to be more widely distributed in Colorado, but with the expansion of development and agriculture, not to mention cheatgrass, their populations have declined.
MYTH: The tail of a skink is “poisonous” and can sting you.
No, their tail is not a stinger and is not venomous.
MYTH: If a lizard bites you, it will hold on until it thunders.
No, they have no reason to hold on that long.
In Egypt, they say that in spring lizards climb an east-facing wall and look to the east. When the Sun rises, the lizards sight have the ability to restore the sight of a blind person.
In Australia, the aborigines believe that the sky will fall if you kill a lizard.
In ancient Egypt and Greek symbolism the lizard represented divine wisdom and good fortune. In Roman mythology, lizards symbolize both death and resurrection because it was thought that they slept through the winter, and woke up at the end of it. Early Christianity associated the lizard with evil. On the Pacific islands of Polynesia and Maoris lizards are revered as a “heaven god.”
Dinosaurs weren’t lizards! Current scientific theory is that dinosaurs were reptiles, but were not lizards. The main difference is the way their legs attach to their bodies. Dinosaurs’ legs go down, as our legs do. Lizard legs go out in a squatting position. It is also possible that dinosaurs were warm-blooded animals, unlike cold-blooded lizards.
Lizards in Colorado
Roundtail horned lizard
Greater short-horned lizard
Texas horned lizard*
Great plains skink
Prairie lizard/Plateau lizard
Desert spiny lizard*
Ornate tree lizard
Longnose leopard lizard*
Eastern collared lizard
Plateau striped whiptail
Lesser earless lizard
Diploid checkered whiptail
Triploid checkered whiptail
(* denotes sensitive species as designated by the BLM)
Found a lizard in Colorado you can’t identify? Colorado Parks and Wildlife has a handy Lizards of Colorado key found here: http://cpw.state.co.us/documents/education/studentactivities/coherpquickkey.pdf
If you find a lizard in the wild, observe it from a distance so it doesn’t run away. Do not try to capture it, as it may lose its tail, or become very stressed. Lizards in Colorado are lucky to live here, so please leave them in the wild, where you found them!
The summer rains have arrived. Yippee! These rains are helpful in so many ways. Perhaps mostly noticeably they provide enough water for the mountain wildflowers to bloom. These flowers coat the hillsides is a glorious canvas of color. The flowers also produce delicious nectar that is enjoyed by many of nature’s creatures. Look carefully and you will see hummingbirds, ants, bees, flies and others feeding on the nectar. When the sun is shining, butterflies are often seen drinking from these fantastic flowers.
What is a Butterfly?
Butterflies are a member of the insect family, and together with moths makeup the order known as ‘Lepidoptera’. The dividing line between butterflies and moths is fairly fuzzy and some creatures could seem to fall into either category. However, the main difference between them is butterflies are generally active in the day and moths are active at night. Also, in a resting position, moths lay their wings down over their bodies, while butterflies stand their wings up so that their undersides may be seen.
Fairly large colorful wings grace the butterfly and give the ability to fly. The large number of yellow winged varieties is probably responsible for the name. The wings seem uniquely designed to help avoid predators, but at the same time to attract mates. Eye patterns in some wings will ward off discerning birds and colorful displays sometimes serve as a warning of bitter flavors to keep away the epicureans. Meanwhile these patterns are recognized by other butterflies of the same species as a call to mate.
Butterflies have a large proboscis, which is actually a mouthpart, and is used to suck nectar and fluids from flowers. While feeding themselves butterflies also serve the function of helping to pollinate flowers.Adult females lay the eggs on a leaf that will become a food source for the new caterpillars. The caterpillars grow bigger and bigger as they eat the leaves. Eventually something is triggered in the caterpillar and it finds aquiet spot to go into its chrysalis phase. The caterpillar does not “build” a chrysalis around itself. Instead, the caterpillar sheds its skin and the chrysalis is underneath.
Their antennae are generally “clubbed” and covered with tiny hairs that also may be found on much of the rest of the body. These hairs tell the butterfly about wind currents, water, vibrations and nearby objects. Butterflies have two compound eyes that see a broad spectrum of light including ultraviolet.
The time lines for (adult) butterflies vary widely, from a few weeks to a couple of years. Some, such as the monarch butterfly actually migrate for various stages and activities. Butterflies also vary widely in size, color and activity.
A butterfly has four stages in its life cycle: egg, larva (caterpillar), pupa (chrysalis) and adult (butterfly). It is a repetitive cycle, but the butterfly does not turn back into an egg!
Like most animals, the male and female adults work together to produce new fertilized eggs.
Adult females lay the eggs on a leaf that will become a food source for the new caterpillars. The caterpillars grow bigger and bigger as they eat the leaves. Eventually something is triggered in the caterpillar and it finds a quiet spot to go into its chrysalis phase. The caterpillar does not “build” a chrysalis around itself. Instead, the caterpillar sheds its skin and the chrysalis is underneath. When the butterfly emerges from its chrysalis, its new wings are fragile. It waits patiently for the wings to dry out and strengthen. Then it flutters away! Many other insects go through similar life cycles.
Colorado Mountain Butterflies and Flowers
There are over 60 species of butterflies in Colorado. Here are some of the more common ones seen in the summer above 8,500 feet and the flowers on which they feed. They vary greatly in size, color and plant food. Read on to learn more about these winged wonders!
Favorite flowers: milkweeds, thistles, dogbane, vetch,red clover, cow parsnip
Appropriately named, this butterfly is identified by thespots within its checkered pattern. There are at least 8 species of checkerspots in Colorado and pattern varies within each species.
Favorite flowers: asters, paintbrushes
One of the largest butterflies you will see, these are also some of the most common butterflies during June and July.
Favorite flowers: many flowers, including red clover,dandelion and thistles
These little beauties are so small, you might miss them…until you startle them and they flutter away. Look for them in muddy, wet areas. They love moisture.Arrowhead blues are one of many species of blues in Colorado. It is differentiated by a tiny orange arrowhead on the outside bottom of each hind wing.
Favorite flowers: anything in the pea family, especially lupines
Easily mistaken for the larger Tortoiseshell, the Comma has a small comma in the center underside of its hind wing. This butterfly hibernates in winter.
Favorite flowers: varies, includes currants
This butterfly is not as common in this area as the name would imply. Look carefully and you may be fortunate enough to spot one.
Favorite flowers: grasses, cow parsnip, bittercress
All photos copyright MK Gunn 2007 – 2012 unless otherwise noted.
Save the Date!
Want to learn more about butterflies and flowers? MK Gunn is leading a Butterflies and Blooms hike up Cascade Creek on Saturday, July 30th, 9:30am – noon. Details can be found here.