Part II: Yosemite's Trees and Animals

You will see a lot of Mule Deer. In fact, you may even get to within 10 feet of one. Mule deer originally received their name because of their large ears, which resemble a mule. They have sharp hearing, great noses and can see very well. The mature doe's will often give birth to twins, while yearling doe's generally only have one fawn. Harsh winters take a major toll on young fawns. As the temperature drops and the snow begins to pile high, these small deer have a very difficult time surviving. Predators, such as cougars, bobcats and coyotes are always looking for the weak and old. Combined with winter ranges that may have diminished food sources, fawns are at great risk. - Deer eat leaves and twigs in the spring and summer, acorns in the fall, and evergreens in the winter. - Male deer lose their antlers after the fall every year. - Fawns (baby deer) do not have a scent, which keeps them safe from predators. Vital Stats Weight: 125-330 lbs. Length with tail: 50-85" No. of Young: 1-4, 2 avg. Birth Interval: 1 year Lifespan: 10 years in the wild

Question 14: What adaptation helps protect fawns from predators?

Ravens are the largest members of the crow-type birds. They are the largest all-black bird and songbird in the world. They can live for up to 30 years in captivity and reach a wing span of almost four feet. The raven is an omnivorous species, meaning they will eat both plants and meat. As much as half of their diet can be live prey. Their diet in the wild consists of small mammals, eggs, nestlings, insects, berries, and carrion. Ravens are often found at high altitudes, even on top of Mt. McKinley at over 14,000 elevation. Ravens will often hide and store surplus food, returning later to eat when necessary. They will also remember where other ravens hide their food, and raid these sites. Ravens have over 30 distinct vocalizations. They also mimic a wide range of sounds and the calls of other birds. Many stories have been told of raven intelligence. They have been known to follow packs of wolves as they hunt, sharing in the meat from the kills. Ravens have also been observed baiting hawks to kill prey, then chasing the hawks away to eat the meat themselves. Ravens often engage in play, both among themselves and with other species. They have been observed harassing wolves into chasing them, only to dodge their jaws at the last second.

Question 15: What are two interesting facts about Ravens?

A day's catch of rainbow trout- "6 for the pan, man!" Most fish in Yosemite National Park have been introduced (meaning they were placed there in the lakes by fishermen). Prior to trout stocking for sport fishing, native fish were limited in both range and number of species. The series of glaciations that covered much of the area that is now the park eliminated all fish from the high country. After the glaciers retreated, the waterfalls and steep gradients that were created on the rivers and streams by glaciation prevented repopulation of fish by upstream migration. Only the lower reaches of the Tuolumne and Merced Rivers were populated by fish when Euro-Americans first arrived in Yosemite in the mid-1800s.Because of severe climatic conditions, low nutrient availability associated with snowmelt over granitic watersheds, and a lack of spawning habitat, fish introduced in many of Yosemite's lakes have not survived.
Fish surveys conducted in 1977 at 102 lakes that have a history of fish planting found that about 55% of these lakes contained self-sustaining fish populations, while 22% of the surveyed lakes had reverted to a natural, fish-free state, and another 24% were expected to achieve this state. A re-survey of some of these lakes in 1996, however, found a number of the lakes expected to go fishless still contained fish. It is estimated that approximately 550 miles of streams in Yosemite support fish.The rainbow trout is the only trout native to Yosemite, and was originally restricted to the Merced River in Yosemite Valley and downstream. Widespread planting of rainbow trout, brown trout, and brook trout has introduced these fishes to many waters in the park that were naturally fish-free, causing adverse effects to aquatic ecosystems.Beginning in 1978, a park policy was implemented that, by 1991, ended almost 100 years of fish stocking in Yosemite. This policy recognized that non-native fish were having an adverse effect on native aquatic ecosystems that had evolved in the absence of fish.

Question 16: What type of trout is the only native to Yosemite?

Question 17: Why doesn't the park stock lakes with non-native trout?

Raccoons are native to North and South America. Within their range, raccoons inhabit the lower elevations, avoiding the particularly harsh winter conditions of the high mountains.The name 'raccoon' comes from the Algonquin word 'arakun' which means "one who scratches with his hands". An average specimen of the Common Raccoon is about 32 inches long including the tail and weighs 11 to 18 pounds. In the northern part of their range raccoons may weigh as much as 33 pounds. The largest specimen ever recorded was over 60 pounds! The life span of wild raccoons is not known but is estimated at seven years; in captivity they may live twice as long. Raccoons are omnivores and their diet includes frogs, crayfish, fish, birds, eggs, fruits, nuts, grains, small mammals and insects. Raccoons are primarily active after nightfall. Raccoons prefer to make their dens in the hollows in standing trees but have also been known to use underground burrows. Their adaptability to the loss of habitat brought on by human development has led them to use abandoned buildings and vehicles as denning sites as well. Don't feed them. They bite. If you feed one and it bites you, you'll have to get 5 shots in your bottom. Ouch!

Question 18 : How can we help keep the raccoons wild?

A wild mule deer wanders across a bridge. This photo was taken from inside a car.

Question 19: How has our interaction in Yosemite affected the natural environment? (Think about roads, hotels, campsites, foot traffic, trash, and other such things and what their affect on the environment).

Yosemite is home to approximately 37 types of trees. You can see these families of coniferous trees in Yosemite: Cypress (Incense Cedar & Sierra Juniper), Pine, Hemlock, Fir, Giant Sequoia, and Yew You can see these families of broadleaf trees in Yosemite: Birch, Alder, Dogwood, Laurel, Maple, Oak, Poplar, Black Cottonwood, Quaking Aspen, and Willow.

This is the called the tunnel tree. Early visitors found it amusing to cut large holes in the Giant Sequoias and drive their cars through them. When the first visitors to the area saw the trees they couldn't believe their eyes. They sent a cut out cross section of one of the trees to the east coast and the people there called it a hoax, they couldn't believe that such huge trees were real. Luckily, John Muir and others fought to protect these great trees from loggers and exploitation. If it weren't for John Muir and other protectors, many of them would no longer be standing. And who can wait 2,000 years for them to grow back?

Question 20: What living things in your area are under protection?

Big Red in the Tuolumne Grove. The Giant Sequoia trees are the largest living things on earth, because they are among the tallest and are the biggest in width. The Coastal Redwoods of California are taller than the Giant Sequoias. However, the sequoia trees are bigger by volume because they have much larger trunks and branches.They are the fastest growing trees in the world.They are also the biggest in width.Their bark can be as much as 3 feet thick.The trees have survived for 2,000 or 3,000 years, some even longer. Some of the largest trees measure 35 feet in base diameter and up to 300 feet in height. The tallest standing giant sequoia is 311 feet tall and the tallest redwood is 367 feet tall.They can grow up to 1 to 2 feet tall per year until it is between 200 to 300 feet high, then, like people, they grow outward. The tree grows at elevations of 6,500 feet.

Question 21: What are some interesting facts about Giant Sequoias? List 4.

This is a Giant Sequoia cone. It is about actual size. It is roughly the size of a golf ball. This small cone gives birth to the largest living thing on the planet. Amazing! Young trees start to bear cones at the age of 20 years. Cones may remain attached to the tree for 8 to 20 years and many of the seeds will be retained. During the late summer, however, some seeds are shed when the cone scales shrink. Most seeds are liberated when the cone dries out and becomes detached. Each cone yields an average of 230 seeds. At any given time, a large tree may be expected to have approximately 11,000 cones. The upper part of the crown of any mature Giant Sequoia invariably produces a greater abundance of cones than its lower portions. A mature Giant Sequoia has been estimated to disperse from 300,000 to 400,000 seeds per year. The winged seeds may be carried up to 180 m (600 feet) from the parent tree.

Question 22: What are 3 interesting facts about Giant Sequoia cones?

These are the Two Towers, found in the Tuolumne Grove of Giant Sequoias. They are hidden from view. While you are in the Tuolumne Grove, try to find them.

This leaf is from a black oak. It is resting on a granite rock. Granite is a coarse-grained, hard igneous rock primarily made up of quartz and feldspar. El Capitan, Half Dome, and all of the other major landforms in Yosemite are granite. It is extremely hard and is often used as a building material. When you walk by the Ahwahnee Hotel, see if they used any granite in its construction.

Question 23: What do you remember about the black oak's history in the Yosemite Valley? (hint: remember part one)

Can you guess which pine cone is the male and which one is the female? Sorry boys, you're the small one on the right. The female cone contains all the seeds and is always much larger than the male cones.

Tree Identification:
Left: Cedar = Flat needles
Middle: Fir = Short needles attached individually to the stem.
Right: Pine = Needles are long and grow in bunches.

After a week of enjoying the park, it is time for the students to give back to the park.A group of Mesa students do a stewardship project. They are cutting out a non-native plant species that has taken over the natural habitat and killed off the native plant species.

Question 24: What stewardship projects have you been involved in, or how have you "given back" to your community? If you haven't yet, in what ways could you?