AY Honors/Mammals - Advanced/Answer Key

2. What mammals in your locality are protected by law? Why?

Most mammals are protected by law in the form of hunting seasons and licenses. It is illegal to kill most medium-to-large mammals in most parts of the United States without a license, and these licenses are only good during certain seasons. Mammals which are considered pests or vermin, such as rats, mice, and groundhogs, are not protected in this way. They can be exterminated at any time. But deer, squirrels, opossums, beaver, muskrat, weasels, mink, fishercats, bobcats, mountain lions, and wolves either have a designated season, during which a licensed hunter may kill them, or they enjoy a total ban on hunting.

The purpose of these laws is to stabilize the population. Generally, hunting seasons are in the autumn, and this is to allow the mammals to reproduce in the spring and summer, but be culled out before winter sets in. In many cases, hunting is the only predation a mammal knows, and without a hunting season, the population would explode. Large populations of deer, for instance, cannot survive the winter, as the available food resources are limited. Without a hunting season, many would starve.

In other cases, mammals are protected because they have been listed as endangered. This usually means that in our unenlightened past, man hunted them to the brink of extinction, or has eliminated so much of the animal's habitat, that it cannot survive without legal protection.

3. How do the processes of birth and care for the young differ in monotremes and marsupials from all other orders of mammals?

Monotremes

Monotremes include the platypus, echidna, and several other species. Monotremes lay eggs. However, the egg is retained for some time within the mother, who actively provides the egg with nutrients. Monotremes also lactate, but have no defined nipples, excreting the milk from their mammary glands via openings in their skin.

Marsupials

Marsupials include kangaroos, opossums, and several other species. The pregnant female develops a kind of yolk sac in her womb which delivers nutrients to the embryo. The embryo is born at a very early stage of development (at about 4-5 weeks), upon which it crawls up its mother's belly and attaches itself to a nipple (which is located inside the pouch). It remains attached to the nipple for a number of weeks. The offspring later passes through a stage where it temporarily leaves the pouch, returning for warmth and nourishment.

4. Name five different ways in which mammals protect themselves and their young, and cite an example of each.

1. Speed: Several species of antelope are able to outrun many other animals within hours of being born. If a predator cannot catch it, it cannot eat it either.
2. Camouflage: Mother deer hide their spotted fawns in the forest. The spots on the fawns make it nearly impossible to see them in the dappled light.
3. Teeth: Many mammals are armed with very sharp and long teeth. If cornered, they will first bare their teeth, and if pressed, they will bite! Raccoons are a prime example.
4. Claws: Many mammals are also armed with long, sharp claws. These can be used offensively for catching prey, or defensively. A prime example would be the bear - nobody wants to tangle with one of those!
5. Quills: Porcupines have specialized thick, stiff, hairs called spines or quills which can be ejected at will into the snout of a potential predator. These quills are barbed at the tips so that they do not come out easily. An animals that finds itself on the receiving end of this formidable weapon will retreat immediately.
6. Odor: Skunks have the ability to spray a foul-smelling liquid on anything that threatens it. The smell aside, the spray can cause irritation and even temporary blindness, and is sufficiently powerful to be detected by even an insensitive human nose anywhere up to a mile downwind. Imagine how difficult this would make stalking other potential prey until that smell wears away!

5. What mammals are agents for the transmission of tularemia, bubonic plague, trichinosis, and rabies?

Tularemia

Rabbits are a major agent for the transmission of Tularemia, which is also known as rabbit fever.

Bubonic plague

Rodents, primarily rats are responsible for the spread of bubonic plague.

Trichinosis

Trichinosis, also called trichinellosis, or trichiniasis, is a parasitic disease caused by eating raw or undercooked pork and wild game products infected with the larvae of a species of roundworm Trichinella spiralis, commonly called the trichina worm.

Rabies

About 50% of the rabies cases in the United States are found in raccoons, though dogs, cats, skunks, and bats are also common sources of the disease. All mammals are susceptible to rabies.

6. List 15 species of wild mammals which you personally have observed and identified in the wild. For each one listed, include the following data:
a. Name
b. Date observed
c. Locality
d. Habitat (woods, field, swamp)
e. Time of day
f. Behavior (what the animal was doing)

This requirement requires either a lot of dedicated observation, or persistence over a long period of time. Get into the habit of logging the requested information (dates, localities, habitats, etc), so that after a period of time, you will have all this data recorded.

If you prefer to dedicate time for observation so that you may earn the honor more quickly, it would be a good idea to earn the Animal Tracking honor first. Armed with the knowledge provided in this honor, you will be better equipped to detect that mammals have been in a given locality, and thus improve your chances of spotting them.

Many wild mammals are very easy to spot in North America, such as deer, squirrels, mice, rabbits, and raccoons. Others are more elusive, such as beavers, muskrats, members of the weasel family, wolves, skunks, porcupines, and bears. However, with persistence, you should be able to spot 15 species.

Perhaps you've recorded some of this information already without trying to earn the honor. Have you ever written about seeing a mammal in an email to a friend or your family? Go through your old email and look for it. The level of detail you wrote about may surprise you. Do you keep a blog? Look there! In fact, recording these in a blog may not be a bad idea...