by Norman W. Hirsch, Certified Texas Master Naturalist
Basic Animal Identification
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Field Trips
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Vertebrates
Birds
Birds are warm-blooded, air-breathing vertebrates. Their body is covered with feathers. Birds have beaks, feathers, wings, and scale-covered legs. All birds lay eggs that are covered with calcium-carbonate shell.
Mammals
Mammals are warm-blooded, air-breathing vertebrates with their bodies covered with hair. All mammals feed their young milk. Examples—Humans, skunks, squirrels
Reptiles
Reptiles are cold-blooded, air-breathing vertebrates covered with a tough leathery skin that has embedded scales. Examples—Snakes, alligators, turtles, lizards. Most reptiles lay eggs, though some give birth to fully formed young.
Amphibians
Amphibians are cold-blooded vertebrates with moist, hairless, and scaleless skin that water can pass through. They lay eggs in water where the young hatch and go through a larval or tadpole stage, breathing air by means of gills. Some larval forms lose their gills and develop lungs for breathing. Example—Frogs (smooth skin, long limbs), toads (warty skin, short limbs), newts, and salamanders.
Invertebrates
Insects—True insects are cold-blooded invertebrates covered with an exoskeleton. Their bodies consist of three regions—head, thorax, and abdomen. They have antenna and six legs. They make up 75 percent of all animal species on earth.
Arthropods—Invertebrate animals having a segmented body to which joined antenna, wings or legs are articulated in pairs. Insects, Arachnids, and Crustaceans belong to this Phylum. Example—Butterflies
Orthoptera—Insects with longitudinally folded, membranous hind wings covered by hard, narrow forewings and having mouth parts for chewing. Examples—crickets, grasshoppers, locusts and cockroaches
Arachnids—Arthropods closely allied to insects and crustaceans but having eight legs and no wings or antenna. The body is divided into two regions and has a breathing mechanism of tracheal tubes or pulmonary sacs. Spiders, scorpions, mites, ticks, and daddy-long legs belong to this class.
Crustaceans—Arthropods with hard shells and joined bodies and appendages, living mostly in water. Examples—Crabs, lobsters, crayfish, and shrimp
Mollusks—Invertebrate animals with soft, unsegmented bodies, usually covered with a hard shell secreted by a covering mantel, and a muscular foot. Examples—Snails, clams, oysters, whelks, and mussels. Slugs, octopuses, and squids are mollusks that have no shell.
Field Trips
Pre-Planning the Trip
Before going on the field trip for observations, establish what you want to look for and prepare for the trip. Decide what species or animals, plants, or both you want to be on the lookout for and refresh your memory on the pertinent facts about those species.
Habitat—Does the subject live in woodlands, grasslands, arid areas, wetlands, streams, rivers, lakes, beach, sand dunes, tidal flats, bays, or the Gulf? Does it inhabit dead logs, trees, brush piles, lumber piles, trash piles, or old tires? Does it live above or below soil level? Add to this list with what you know.
Habits—These are the natural behaviors of the subject.
Geographic Region—Know the geographic region you are planning the trip for. The vegetation of the region will indicate what species of animals will be supported.
Time—Consider both the season of the year and the time of day or night
Moon Age and Position—The lunar month is a 29.5-day cycle beginning with the new moon. The diagram shows what the different phases of the Moon look like. It appears that the Moon repeats certain phases: there are two crescent, gibbous, and half phases each month (each cycle). These phases are not exactly identical, however. Look closely at the diagram. You will notice that during phases 1 through 5, the amount of lighted area increases over time from right to left. When this occurs, the Moon is said to be waxing. During phases 5 through 8, the amount of light area decreases (or the darkened area increases) from right to left. When this occurs, the Moon is said to be waning. Therefore you can tell if the Moon is waxing or waning based on whether the right side of the Moon is dark or light. Astronomers use this to distinguish between the repeated phases of the moon by referring to the waxing or waning crescent, gibbous, and half phases. The importance of this to us as naturalists is that the phases of the moon seem to affect the activity levels of wild animals.
Equipment Required—You may want to take maps, charts, field guides, note pads, binoculars, telescopes, hand lens/magnifying glass, and camera.
Weather Conditions—Choose proper clothing for the event and have additional clothing if there is a change in the weather. Remember, this is Texas.
Nourishment—Carry snacks, lunch and water. Maintain energy level and body fluids.
First Aid—Always carry a fist aid kit; know how to administer first aid and CPR. Take lessons in basic first aid and CPR. It’s ok to carry your cell phone for emergencies but turn it off on the trail.
Site Access—Is the site public or private? Obtain passes, permits, reservations or permission before entering the site.
Set the policy on the do’s and don’ts for each field trip. Follow the rules and regulations of park or landowner. Removal of—or damage to—natural property at a site is against the law.
Note: Add your own requirements based on each specific field trip.
Taking the Trip
Field Skills
Move quietly—Any noise or distraction, such as conversation or swishing clothing, can prevent you from observing your subject.
Move gently—Animals are sensitive to abrupt movement. Sudden hand-waving, finger-pointing, or binocular-raising will get the attention of the animal, and it may leave the area. Reflections from jewelry will also signal your presence.
Move slowly—This is not a track race. Slow walking or standing in one spot will produce the opportunity for more observations than thrashing through the vegetation or the water. Heavy or rapid footsteps will generate vibrations in the soil. Animals can detect these vibrations, and they may give your location away.
Watch for movement—Take the “wide view” approach. Do not focus on one item, but let your eyes scan a large area, front to back, side to side, and up and down. When you detect movement, then focus on the movement area.
Follow sounds—As your eyes are scanning the area, use your ears to listen for sounds from all directions. Many times you will hear a sound from an area different from where you are looking.
Pay attention to behavior—What is the animal doing? Is it eating, hunting, mating, drinking water, resting, sleeping, running or standing, or looking at you?
Note odors—What is in the air? Yes, it is a skunk. This is probably the first smell that we learned in our youth and will never forget. Let your nose present to you what your eyes and ears cannot detect. Are you upwind or downwind from your subject? If you are upwind, the subject will smell you and take notice of your presence. If you are downwind, your human smell is carried away from the subject.
Remember SLL—Stop, look, listen—That is what animals do to survive. As we look for them, they are looking at us.
Note: You are in their house.
Who’s Been Here? Who’s Here Now?
Who Will Be Here Tomorrow?
Theses are the questions that we want to take to the field. Using these questions, we will energize ourselves—and those we teach—and nature observations will be fun and educational. Like the skunk smell, we want to keep our field trips in our memory to share with others.
Who’s Been Here?
Signs to look for when on the nature trail, or wherever you are include tracks, damaged or disarranged vegetation, and scat (animal feces).
Tracks
Tracks are the history markers of an animal or animals that were here before us. These are the first signs we want to look for. In most sightings, they may be incomplete or faint prints. A good clear print will be present in slightly wet, shallow snow that isn’t melting or soft mud that isn’t actually wet. A good location to look for tracks is on the banks of ponds, creeks, streams, or rivers; in wet and dry beach sand; in the mud left from rain puddles; and on animal trails that lead to a water source or food area.
Identifying Tracks
Measure the length of the print, count the number of the toes, note spacing between the toes and whether or not they are parallel, check for claw marks and how far away they are from the body of the print. Look for a heel and dewclaws and note whether fur on the sole of the foot has made the print less clear. Try to distinguish between fore and hind prints. Fore prints may be larger than the hind prints or may be the same size Prints may overlap, or they may be directly on top of each other.
Snake tracks can be so similar that identification of the species is next to impossible and even the direction of travel is hard to determine. A wide trail with strong side looping indicates that the snake was moving quickly; a narrow, uneven trail indicates a slower speed.
Multiple, dissimilar tracks in a disturbed area may indicate a conflict between two different animals claiming the territory or in combat for food. Many similar animal tracks in a disturbed area may indicate a conflict of males for a female.
Look beyond the single print and search for others to determine the travel direction. Follow tracks, since they can lead you to an animal’s home in the ground, a tree, rotten log, brush pile or under your house. Not only did my family like our house when we grew up, so did several nine-banded armadillos (Dasypus novemcinctus).
Disturbed Vegetation
Areas of tree trunks with bark removed or clawed may indicate animal climbing activity—to a food source or to their home. Look for claw marks.
When traveling, heavy animals will break twigs, flatten vegetation, and stir up soil. Look for vegetation that is bent over or mashed down. Flattened vegetation may indicate a bedding or rest area. Broken or rubbed branches, chewed leaves on shrubs, trees or grasses.
Scat
Droppings will show what the animal has eaten. Is the scat in the form of pellets, piles, splats, or cylinders? Do not be hesitant to stop and probe the sample. Break it open with a stick and analyze the contents. What do you see—seeds, fur, bones, grass, berries, or insects? This analysis is a valuable tool for identifying the animal. For example, birds eat berries. Many times the berries are not completely digested as they pass through the bird. When you can identify the type of berry, you can determine what the bird might have been by researching what birds are known to eat that berry. Also note that this process is how many plants are propagated. Birds and animals are Nature's farmers. The scat remains will vary with the season, based on the availability of food and water in the habitat range of the animal.
Typical scat readily found is from birds, rabbits, deer and raccoons.
Remains—Bones or Shells
Many times you will encounter the skeletal remains of an animal or insect. This becomes a forensic identification event. Leave the remains in place and analyze the position of each component and field location. Are the remains covered with fur, skin or feathers? Are the remains small or large? Take photos for later study.
You can observe the remains of insects in spider webs. Study the unique method of web encasement used by the spider has captured this meal.
Who’s Here Now?
We are. As humans, we think that we are the superior animals, no matter where we are. However, this attitude must change if we want to truly appreciate our natural world. We are now visitors to the home of the fauna and flora around us. Now we are subject to the scrutiny of the animals around us.
We must respect every aspect of our surroundings. Every element in an ecosystem contributes to life there.
Who Will Be Here Tomorrow?
The future of nature is entirely up to the human race. Each time a developer destroys a virgin timber forest or grassland, dams a river, or fills in a wetland the plants and animals in that habitat will be pushed into a desperate struggle to survive.
A good example is the American alligator in the state of Florida. The alligator was over-hunted for meat and hide and was rapidly becoming extinct. The U.S. Fish and Wildlife Service and the state of Florida placed the animal on the endangered species list to allow it to increase its population.
In the meantime, developers were building houses and destroying thousands of acres of the alligator habitat to do so. No concern was given to the land under development or to its inhabitants.
The alligator population rapidly increased, but with little habitat to support its growing numbers, the result was over-population. Some alligators resorted to penetrating residential areas and eating dogs and cats to survive. On some occasions, humans became the food source—remember, the alligator does not know the difference between a handout and a hand.
This type of activity continues today, no matter how many regulatory governing agencies have taken action to help retain what nature we have left. But we are trying.
Many landowners of large acreage are active in land management programs that restore grasses, shrubbery, water sources, soil, and animal populations. Many conservation and restoration programs are sponsored by the Texas Parks and Wildlife Department, USFW and State Universities that conduct research activities to help redevelop destroyed land and food sources.
The key word for us as naturalists is “respect.” We can help by respecting every element in the ecosystem around us. On our hikes and in our nature studies, respect will help ensure continuation of the ecosystems around us, and nature will present its beauty to us.