Name: _________KEY_____________

This take-home learning experience will be due at the beginning of class next week. You are allowed to use whatever class notes you have taken, or handouts I have given you. You are not allowed to work with other students. If your answer matches someone else’s answer, neither student will receive credit for the answer. If you do not understand the question, you should contact Tiare by Wednesday to receive help. Your best 15 answers will be graded, your worst 2 answers will be thrown out.

1) Describe an adaptation for each of the following parts that allows beavers to live in water:

(from lecture notes)

Glands – a set of oil glands discharges oil used to waterproof the fur

Tail – serves as a rudder, alarm system, store fat for winter

Feet – rear feet webbed for swimming, split nail for grooming, front feet can feel underwater

Nose – when beavers emerge from their den, they swim around the pond sniffing to see if there is danger on land

Ears – lay down flat for swimming aerodynamacy, have a valve in the ear cavity to keep water out

Eyes – have nictitating membrane, or a third clear eyelid, used as goggles when swimming, eyes located on top of head for swimming

Mouth – have special skin flap behind front teeth allowing them to chew underwater

Fur – thick coat with fat layer for insulation in water

2) How do beavers survive the winter?

(from IMAX movie)

They stockpile branches underwater.

The dam is raised to a height to keep the water high enough that ice doesn’t freeze all the way to the bottom of the pond. After ice has formed, the dam can be lowered, creating room between the top of the water and the bottom of the ice.

They also live in their warm, dry lodges with many other family members.

They store fat in their tails and live off the fat.

3) A pair of beavers in Alaska built a dam on a creek running alongside a college dormitory. As a result of the pond created by the dam, the dorm’s parking lot flooded. The college president called the campus maintenance staff and said a flooded parking lot is unacceptable – students must be able to park there. Besides live trapping the beavers and relocating them, create a solution the staff can employ.

(from reading out of "Beavers, A Wildlife Handbook")

Scent repellents – such as predator urine

Inverted intake pipe to drain pond level down, but not create trickle noise as it drains

4) We learned the following concepts of nature awareness: baseline, bird alarms, concentric rings of disturbance, wide angle vision, focused listening, fox walking, patterns and camouflage, and search image. Why do these techniques come so naturally to us, or why do we all have the capability of using these techniques?

(from Deb’s talk)

Because humans have evolved and survived for thousands of years by using these same techniques. Humans whose brains process and make use of these techniques are the ones that were selected for by nature – meaning those whose brains didn’t work that way, or who didn’t pay attention to nature signs, died. (natural selection)

5) Why was the series of questions Deb asked you (about what you saw when you walk out your front door that morning) called the "tourist test"?

(from Deb’s talk)

The name comes from the idea that tourists to an area are just passing through. It is almost as if we don’t live here (in our home habitat) anymore, we are nearly tourists that are "just passing through".

6) List at least two reasons why you shouldn’t pick up a rough skinned newt.

They secrete toxins, or poisons, through their skin that could kill a human if ingested.

The oils, salts, lotions, or whatever is on our hands moves straight through their skin and into their bodies, which can injure them.

7) In your own words, describe the transformation male rough skinned newts are going through at this time of the year. Describe the breeding ritual of the newts.

(from two handouts on rough skinned newts)

It is breeding season and the male newts arrive at the breeding sites before the females. Their dry, bumpy skin becomes moist and smooth, their tails flatten, and their cloaca enlarges, and rough, dark "nuptial pads" develop on their feet and hind legs.

The male entices the female by clasping her from above,. Stroking her with his hind legs, and rubbing his snout across hers. He deposits a spermatophore on the pond bottom in front of her, and she picks it up with her cloaca.

8) A watershed is an area that collects, stores, and releases water.

(from water quality lecture)

Name at least one way a watershed collects water:

Geology, vegetation, manmade surfaces

Name at least one way a watershed stores water:

Wetlands, lakes, reservoirs, soil, groundwater, snow and ice, biology

Name at least one way a watershed releases water:

Streams and rivers, evaporation, human engineering

9) Why does runoff occur? Why should we be concerned with urban runoff?

(from water quality lecture)

Runoff is defined as precipitation in excess of what will infiltrate into soil or can be stored within the watershed.

Urban runoff is the water flowing across man made surfaces (such as roofs, lawns, streets, etc.) It generally picks up and carries along with it anything in its path – soil, pesticides, fertilizers, oil, etc., and dumps it into the stream.

10) What is a hydrograph?

(from water quality lecture)

A hydrograph displays how a stream discharge changes over time.

Lag time is the time interval between the peak in the rainfall and the stream’s discharge peak. Label the lag time on the hydrograph to the left.

11) In the hydrograph, explain why the dotted line discharge (the forest or countryside) differs from the solid line (the urban area)?

Trees and vegetation in a watershed intercept precipitation. Precipitation infiltrates into the soil and slowly drains to a river. This reduces run-off, lengthens time lag, and reduces river discharge. In urban areas with a lot of impervious surfaces, time lag is shortened because water quickly drains straight to the stream. This will decrease the time lag and increase discharge.

12) What causes turbidity? What is the effect of turbidity on aquatic organisms?

Turbidity is caused by suspended particle from soil erosion (human disturbance, natural cutting of river, or bottom feeders stirring up sediments) or algae growth (can be enhanced by nutrient runoff, increased sunlight), and wastewater dumping.

Turbidity blocks the amount of light that can penetrate the water surface, reducing plant photosynthesis, reduces visibility for visual feeders, and smoothers eggs, as well as clogging gills.

13) Show how you would measure the length and width of one of the tracks to the left by drawing in the appropriate lines.

(from tracking day)

Describe the toe pads of the tracks:

There are 5 finger-like toe pads on the front and hind foot.

What animals might these tracks belong to, based on the toe pads?

(from Steve and Deb’s talk)

Weasel Family (mustelids)

14) What are the three things that affect track appearance?

(from Steve)

Soil (what the substrate is)

How old it is and how it weathers

What the animal was doing (activity)

15) Describe at least 4 characteristics of a red fox track.

(from reading on red fox, Steve’s talk)

16) Explain how a beaver dam affects the following water quality parameters:

(from beaver dam lecture)

Temperature - The ponds have higher Ts due to slower water with more surface area and the decrease in shade due to felling of trees

Dissolved oxygen - The oxygen content decreases in ponds due to slower moving water and less surface are per volume being exposed to the atmosphere.

Turbidity - Turbidity decreases in ponds and downstream because as the water slows the sediment falls out of suspension

17) How does a beaver dam change the organisms found in the riparian zone (the area around and in the original stream)? (from beaver dam lecture)