Download RL3 Guide Manual HANDBOOK OF RIVER ORGANISMS

RL3 Guide Manual
HANDBOOK OF RIVER ORGANISMS
PROTISTA
Alga, Algae (pl)
Algae are plant-like organisms that contain chlorophyll and make their own
food. Unlike plants, they are not rooted; nor do they have flowering parts.
They are therefore classified Protista. Algae vary greatly in size from
microscopic to saltwater algae 200 feet long. Their fresh water habitat may
be still or flowing water. They can exist in temperatures ranging from
glaciers to hot springs. They may be green, blue-green, yellow, red, or
brown in color and can vary in shape and size. Algae exhibit many
adaptations for staying put (not being washed away by wind, current, wave
action) and for maximizing photosynthesis for growth. Adaptations for staying put include
holdfasts (not true roots) or growth on hard surfaces. Adaptations for maximizing photosynthesis
are large surface area (e.g sea lettuce) and floating near the surface (e.g. Nostoc.)
Algae are very important as food; they are the base of many of aquatic and land food chains (web).
Algae are eaten by microscopic planktonic animals (e.g. protozoan and rotifer), wriggler (immature
mosquito), tadpole, freshwater snail, worm, water boatmen, clam, crayfish, catfish, sunfish, painted
turtle, young snapping turtle, and adult mallard. An important by-product of plant and algae
photosynthesis is oxygen gas. Algae living in fresh water and marine environments produce 3050% of the oxygen available to animals on earth. Algae also benefit the river basin system by
providing habitat for small organisms such as protozoa, rotifer, and immature animals such as snails
and fish.
PLANTS
Plant Basics
1. Plants make their own food thru the process of photosynthesis, using the sun’s energy,
water, carbon dioxide, and minerals in the presence of chlorophyll to produce glucose,
oxygen, and water.
2. A plant or a protist is at the base of every food chain.
3. Water’s edge plants provide food, habitat, supply oxygen in the water, and hold soil.
Spikerush
Spikerush is an emergent water's edge plant that can grow in many soil
types in floodplains along rivers and streams. Emergent plants are rooted
and have parts sticking up out of the water. Spikerush can vary in size
from slender, thread-like stems less than an inch tall, often mistaken for
grass, to medium stems about 8" tall up to plants of about 14". Spikerush
is a sedge that produces seeds at the tip of each stem-like leaf. The seeds
are eaten by mallards and muskrats, but the main importance of the plant is
not as a food source. Its main value is soil-holding, which helps other
food-producing plants grow in the area and thereby helps to enrich the area.
Spikerush also helps keep the water clean. Soil clings to the mesh of fine
roots and prevents it from being washed into the river where it could clog
the gills of fish and other gill breathing animals.
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Bur-reed
Bur-reed is an emergent water's edge plant that lives in quiet fresh water
where there is little current and a mucky bottom. Bur-reed reproduces by
seeds and rhizomes. (Rhizomes are underground stems that new plants may
sprout from.) Each bur-reed plant has long, thin, green leaves that stick up
out of the water. The leaves have air spaces inside that help them float when
the water rises. Each plant has a long, crooked stem with several pricklylooking seed packets on it. The color of bur-reed is an intense shade of light
green. Adult mallards consume the bur-reed seeds. Muskrats eat the whole
plant, feed it to their young, and use it in home construction. Bur-reed leaves
on the water are usually a sign that a muskrat has made off with the choicest
plants.
Silky Dogwood
Silky dogwood is a wetland shrub that grows on the banks of fresh
water streams and ponds. A cousin of the more familiar flowering
dogwood, it is a supple plant. Silky dogwood branches bend
gracefully out over the water, putting down roots into the bottom of
the river out from the edge of the bank. This continually increases
the shaded and protected area for mallard ducklings, bullfrogs, and
other animals. The new root system forms quickly, holding onto
muck, light soil, and debris, preventing them from being washed
away and thereby allowing more plants to grow.
The silky dogwood has reddish branches that become loaded with
flat-topped greenish buds early in the summer. The buds develop into fragrant, flat clusters of white
flowers in July. By the end of summer, flat bunches of blue berries have formed. Almost all
animals, particularly songbirds, raccoons, squirrel, ducks, opossum, and skunks, enjoy these berries.
Black Willow and others
The black willow is a native species of wetland
tree. Black willow and others of its family such as
pussy willow are the best plants at holding soil in
floodplains. The black willow often grows more
than one trunk. The trunks sprawl out on the top
of the ground, helping to hold the bank. Its root
system is extensive and holds much soil. Deer eat
the tender new shoots of the black willow;
muskrats eat young willow plants, as well as new
twigs, leaves, and even roots.
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ANIMALS
Water Strider
The water strider is a water bug. Bugs are insects with sharp, piercing,
sucking beaks. They stick their beaks into their prey (other insects)
and suck out the body juices for food. The water strider cannot dive,
but it can scoot rapidly about on the surface of the water on its hairy
legs. The wide spread of its two long pairs of legs enables its light
body to be supported by the surface tension of the water. Some water
striders' feet are oily, which prevents their getting wet and sinking
through the surface. (Often you can see little shadows on the bottom
of a river or pool from the 'dimpling' of the water's surface by the weight of this insect's body.) The
water strider likes calm water and a combination of light and shade. It eats by reaching underwater
with its short front legs and grabbing wrigglers, water boatmen, mosquitoes, whirligig beetles or
smaller water striders. The water strider is an important scavenger. It feeds on any insects that fall
to the water's surface. Water striders are eaten only by a few organisms: larger water striders, water
boatman, and great blue heron. Its main value is in controlling other insect populations and in
helping to maintain oxygen in the water by its scavenging.
Dragonfly
The dragonfly adult, the world's fastest insect, is often seen
zooming, darting, or hovering over a pool, pond, or river hunting
for food. It has been clocked at speeds up to 60 m.p.h. Its body
structure is adapted for swift, sustained flight. Dragonfly wings are
strong yet flexible. Strong chest muscles move the wings, stroking
one after another, not together as in other insect flight. When at
rest, the dragonfly holds its wings spread out. The compound eyes
of the dragonfly are huge in proportion to its body. Each eye is
composed of 10,000-30,000 facets. These eyes operate as bifocals,
the top for distance, and the bottom for close vision allowing the dragonfly to see everything around
them.
While flying, the dragonfly catches and eats other flying insects, especially mosquitoes. It grasps
these with its legs and feeds them into its mouth. Its strong jaws tear the food apart and pass it back
into the chewing parts of the dragonfly's mouth. Dragonflies are important as consumers and
controllers of other insect populations and as food for water striders and boatman and larger
organisms (birds, frogs, toads, and fish.)
Damselfly
The damselfly is frequently mistaken for a dragonfly. Both have vivid,
iridescent coloring. Both have tapering abdomens that suggest the
capacity to sting, but cannot. They inhabit the same kinds of areas, hunt
similar food and are eaten by similar animals. The damselfly, however, is
smaller and more slender than its larger relative. It is much less powerful
in flight, fluttering haltingly from perch to perch. At rest its wings are
folded together above the body. This is the easiest way to distinguish it
from the dragonfly.
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Mosquito-adult and wriggler
The mosquito adult is a flying insect that feeds on plant juices. It has a long, thin,
sharp, mouth tube to suck these juices. The tip of the tube of the female mosquito
is sharp so it can pierce the skin of birds and mammals to suck blood. The meal of
blood enables approximately 400 eggs to develop inside the female's body instead
of only 40.
Mosquito eggs are laid in any still body of water and hatch into larvae called
wrigglers. The wriggler attaches itself to the surface of the water by a breathing
siphon. It hangs head down into the water from the surface, sweeping algae,
protozoa and rotifers into its mouth with specialized hairs. It protects the oxygen
supply in the water by eating algae. It pupates underwater and then emerges to live on land as an
adult. Some mosquitoes spread disease as they travel from one animal to another. But both
wrigglers and adult mosquitoes are very important as food for fish, other water insects, frogs and
birds. Mosquito wrigglers are an important food source for mallard ducklings.
Whirligig Beetle
Beetles are insects that bite and chew their prey. The whirligig is a
blue-black or dark bronze-colored beetle about one-eighth to 1 3/8
inches long. It helps control insect populations by feeding on live
insects, like mosquitoes, and on dead insects it finds on the water,
even ones as big as dragonflies. Whirligig beetles are most often
seen swimming around and around on the surface of a still part of a
body of water. That is how they got their name. Whirligigs have divided eyes producing two-level
vision for hunting above and below water simultaneously. It can dive under water to attack its prey.
Its outer wings hold an air supply that lets the beetle return to the surface. Whirligig beetles are
food for water striders, fish, mallard ducklings, birds, and snakes.
Water Boatman
The water boatman is a dark grayish aquatic bug about one-half inch
long. It sucks juices with tiny sharp sucking tubes from anything it can
find or catch on the water's surface--plant or animal, alive or dead (algae,
snails, insects, small fish.) It eats a lot of decaying material on the
bottom of river pools, ponds, and lakes. The supply of air that clings to
the water boatman's body when it dives makes the insect buoyant, so it must grasp underwater
objects or plants in order to remain submerged. It may also be seen rowing around on the surface of
the water with its oar-like hind legs looking for food. Water boatmen are a food source for fish,
turtles, and water striders.
Freshwater Snail
The freshwater snail is found in still waters of almost all streams, lakes, and
ponds with temperatures between freezing and 85 degrees F. There are both
hard- and soft-shell varieties. Most are vegetarian; they graze on algae-covered
surfaces or on dead material. The snail scrapes algae off these surfaces using
its radula, a rough tongue that is like sandpaper. The tongue is covered with
hundreds of tiny,
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sharp edges. The snail also has sharp jaws that can bite off small pieces of plants that are ground
against the roof of the mouth by the radula. The front portion of the radula wears away from this us,
but it is continuously replaced as it grows from the back of the snail's mouth. Freshwater snails help
protect the oxygen supply in the water by eating so much algae. Snails are a great bite sized meal
for fish, turtles, or a raccoon. Small snails are eaten by insects such as the water strider and water
boatman.
The extendable portion of the snail's body is called the "foot." This "foot" contains the reproductive
and nervous systems and part of the abdomen. The snail moves either by contracting its "foot" or
by spinning itself upward off the bottom through the water. As it moves, the snail leaves a mucus
track that acts as a sticky pad to collect food or as an anchor line for the snail. At the base of the
tentacles on the "foot" are the snail's eyes.
Some snails have lungs; some gills. A gill-breather has a fingernail-like disc attached to the foot
that the snail can draw tightly in to cover its shell opening when exposed to air.
Freshwater Clam
Freshwater clams can be found in all kinds of fresh water
where the water flows slowly over gravel or sand shallows.
They are most abundant in large rivers and streams.
Freshwater clams have two shells hinged by elastic tissues
(see illustration). They range in size from under one-half
inch to nine inches long. The short side of the shell is the
front. With its shells apart, the clam extends its "foot" out of
the front end. It stretches and pushes its "foot" down into
the sandy or gravelly river bottom. The implanted "foot" swells and anchors the clam, giving it a
hold. The clam then contracts muscles inside its shell and pulls the rest of its body forward. Clam
trails look like a line drawn in the sand by a stick.
To eat, the clam extends its "foot" down into the bottom and pulls its shells after it, until the clam is
half buried. With its shells slightly parted, the clam draws in water containing air and food (algae
and decaying plants and animals.) Tiny gill openings accept the water and air; food particles are
trapped in mucus and passed to the mouth. The clam's digestive system processes food back to a
waste opening just above the intake opening.
Clams are important as food in all stages of their development for many organisms such as fish.
Clams are as important for controlling algae, for filtering impurities from the water as they eat, and
as a bite sized meal for larger organisms such as raccoons or turtles.
Shiners
Shiners are classified in the minnow family. They are two to
four inches long with a single dorsal (back) fin, and most are
very colorful. They live in slow-flowing shallows and pools
that are bordered by vegetation. They eat lots of insects
(wrigglers, whirligig beetles, mosquitoes) helping to control
the insect population. They also eat worms, small snails, clams, smaller fish and some plant
material.
Shiners are an indispensable middle link in the food web of the river. All larger fish, many birds,
and other animals are fed by the offspring of repeated matings of these small fish. Shiners are eaten
at every stage of their life--egg, pinhead (hatchling), and adult.
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Sunfish
Bluegills and pumpkinseeds are two types of sunfish. The
pumpkinseed likes clear, weedy streams and ponds, but bluegills
require some fairly deep, cool pools that can hold more oxygen. In
summer, pumpkinseeds can be seen in sunlit shallows, guarding the
saucer-shaped nests they have swept clean on the bottom. The body
of the sunfish is roundish--about half as deep as it is long. Sunfish
have spiny rays on the front section of the top fin and a notched tail.
Sunfish eat more animals than algae. They feed on worms, mosquitoes, dragonflies, damselflies,
and water boatmen, as well as frogs and small fish. They have bony tooth-like projections that can
crush snails, clams, and crayfish. Because of their small mouths, sunfish can eat only the smallest
shellfish and fish. A major value of sunfish is that they are food for great numbers of aquatic and
terrestrial animals (fish, turtle, raccoon, northern water snake, skunk, kingfisher, great blue heron) at
all stages of their lives. Many people find mature bluegills good to eat.
Catfish
Catfish and bullheads range in size from small to very
large and are found in all types of freshwater habitats.
Some prefer clear waters; some prefer vegetated areas
while others can tolerate silt in the water. All commonly
feed at the bottom on all types of animals, dead or alive,
such as worms, mosquito, wrigglers, dragonflies,
damselflies, snails, clams, small fish and crayfish. They
also eat algae. Since catfish are scavengers they protect the oxygen supply in the water by eating up
decaying matter so the decay process won’t use up the oxygen. Catfish from small fish to adults are
a great meal for sunfish, largemouth bass, snapping turtle, raccoon, skunk, northern water snake,
mallard duckling, kingfisher, and great blue heron.
Largemouth Bass
Largemouth bass, which can grow to over two feet in length, are the largest members of the sunfish
family. They live in all fresh water ponds in the basin,
including river-ponds. They can tolerate warm water
(up to 90 degrees F) and therefore can inhabit sluggish
rivers and shallow, weedy lakes. They usually stay
close to vegetated areas from which their prey is likely
to emerge.
The size of the mouth of the largemouth bass, which
extends behind its eye, enables it to devour nearly anything that comes within reach. Fish account
for 60% of its diet, but the largemouth bass also eats water boatmen, mosquitoes, wrigglers,
dragonflies, damselflies, snails, crayfish, shiners, catfish, sunfish, smaller bass, tadpoles, frogs,
water snakes, small muskrats, ducklings, and squirrels. The largemouth bass converts masses of
smaller animals into an efficient meal for larger organisms, including man. This major predator
improves prey populations by weeding out weaker, less wary and less skilled individuals of other
species. Each stage of the bass’ life cycle--egg, fry, adult--provides food for other organisms,
aquatic and land.
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Bullfrog
The bullfrog lives in wetland areas around still or flowing water in the
basin. A bullfrog may grow so large that it measures eight inches tall when
sitting. Its hands are un-webbed, leaving the four fingers free to grip prey.
Its feet are completely webbed for strong swimming.
Its predation is usually shore-based. The bullfrog does not hunt, but
remains seated at the water's edge of a river cove or pond--or on some
hummock or log in a swamp--waiting for food to come its way.
The bulk of the bullfrog's diet is insects (insect control), including mosquitoes, dragonflies, and
damselflies. It also consumes young turtles, snakes, slow or sick fish, and other frogs. Some
bullfrogs are so large they can even eat a baby duckling, a very nutritious meal!
Bullfrogs are consumed at all stages of their life--egg, tadpole, and adult--by birds, snakes, and
mammals (raccoon, skunk, opossum, wolf), and are therefore important as prey as well as predators.
Between babyhood and old age, snapping turtles consume almost anything edible--plant or animal-in their preferred environment of muddy bottoms of river pools and ponds. Adults consume a lot of
aquatic vegetation, including floating and submerged plants, in addition to the algae that is mainly
eaten by young snappers. Big snappers eat snails, clams, crayfish, small fish, and baby ducklings.
Smaller ones eat worms and water boatmen. As scavengers, snappers help clean up dead animals
that would otherwise use up the oxygen in the water in the process of decaying. Adult snapping
turtles have almost no predators, but their eggs and young are eaten by a variety of land and aquatic
animals.
Northern Water Snake
The northern water snake can grow to as long as four feet, but is not
dangerous to people. Its habitat is in and around all bodies of water in
the basin. It can swim against the current. Sometimes it lies in the water
along the river's edge to catch crayfish or fish slowed by weakness or
disease, or rests on low branches over water to watch for fish or frogs, its
main food. It helps control insects by eating water bugs and beetles,
mosquitoes, dragonflies, and damselflies. The northern water snake is
one of the very few animals that preys on the kingfisher population,
devouring the eggs or young by invading nest holes. A water snake kills
its food by swallowing it whole. Its jaws stretch apart so it can even
swallow duck eggs or small animals, like rats. Since the northern water
snake is a scavenger it helps protect the oxygen supply by eating up dead matter.
Snapping Turtle
The snapping turtle is easily identified by its spiked tail (as
long as or longer than its body) and neck, its rough, ridged
carapace, and its large head. The carapace protects the soft
body of the turtle. It is not a shell; it is actually the turtle's
rib cage, carried on its back and covered with tough,
fingernail-like plates. The turtle also has a protective shield
or "plastron" under its body. The small size of the
snapping turtle's plastron allows the animal freedom of
movement. Snappers are known for their powerful beak-like jaws and their ferocious behavior. It
can lunge and stretch its head and sharp jaws well beyond its body. It is fiercely defensive on land
and therefore best avoided.
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Kingfisher
The kingfisher is easily identified by its irregular flight pattern and by its
raucous, rattling cry. It is a nearly fearless, territorial diving bird. It is built
for diving with a very large crested head and a long, heavy beak. Its
shoulders and chest are heavy, tapering to a comparatively short tail. Its legs
are very short and its feet are tiny. Its plumage is slate blue. It lives along
good fishing streams and ponds. The kingfisher nests in a 4-5 foot tunnel
dug straight into a bank.
As its name indicates, the kingfisher eats mostly fish, usually of small to
medium size. It catches them by diving straight down at them, often from a
high limb above the water. It can dive into a shallow, fast stream to get a
fish and pull out without breaking its bill on the stones.
The kingfisher protects the basin by keeping the populations of the fish it eats in balance and
improves these species by eliminating weaker individuals. Because of its territorial instincts, it also
protects the river from being over fished by chasing other diving birds, including competing
kingfishers, from the area it has claimed. Kingfisher eggs are eaten by raccoons, and the eggs and
young are eaten by the northern water snake.
Mallard Duck
Ducks are swimming birds that have waterproof feather-coats
and webbed feet. The male mallard can be identified by its
glossy dark green head. The female is duller, with brown and
white flecked feathers. The mallard is abundant throughout
North America, Europe, and Asia. It lives in or near wetlands
or ponds, along rivers or other places in the basin.
The mallard is a dabbler. It feeds on algae and helps to keep
algal growth in check to protect the oxygen supply in the
water. It also eats plants that grow in the water and the seeds
of water plants. Adult mallards are a good meal for many
larger animals. The eggs they lay and the ducklings that hatch
are favorite foods for many other animals, including the
raccoon and the northern water snake.
Mallard Duckling
The diet of the mallard duckling is very different from its parents' diet. Baby
mallards mature in one summer. Eating animal food helps them to grow fast.
They consume water bugs and beetles, mosquito wrigglers, worms, tadpoles, and
small or newborn fish. The baby mallard, like all insect eaters, performs a special
role in the basin by controlling insect populations. Insects comprise three-fourths
of all the animal life on earth. Without the animals that consume them, insects
could multiply rapidly and monopolize the food on Earth.
After they have hatched, the babies paddle with their big webbed feet to follow the mother mallard
to eating and resting places in the marsh and along the water's edge of streams and ponds. Usually
these areas are safe because they are shallow. Deep water is dangerous, because a snapping turtle or
largemouth bass could swim underneath to grab the duckling by those big webbed feet. Bullfrogs
and raccoons also eat ducklings. The mallard duckling is important in the basin as a food source for
larger animals.
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Great Blue Heron
The long-legged great blue heron, standing four feet tall, is an
impressive wading bird. It nests in tall trees around the wetlands of the
basin. The nests look like platforms of big sticks and are grouped in
colonies of 30 to over 150, depending on the feeding and protective
features of the area. The wastes of these large birds contribute
significant enrichment to the local ecosystem.
Great blues have three ways of hunting food taking advantage of their
long legs: standing still in shallow riffles, pool, or shore areas and
spearing or seizing fish or other animals; stalking in knee-deep water,
with long neck stretched forward, making sudden steps and lightningfast thrusts of the neck downward into the water; a cooperative fishing
technique, wherein a heron group makes a circle or line to stir up the
water, flushing their prey.
The great blue heron eats fish up to about a foot in length, crayfish, young snakes, water beetles and
water striders, and dragonflies. It also consumes a great many frogs and some young turtles. Like
many predators of aquatic animals, the great blue helps improve the species on which it preys. Its
eggs are eaten by raccoon and opossum.
Muskrat
The muskrat is a large semi-aquatic mammal living both on
land and in water. Its body is covered with soft, dense,
waterproof, chestnut-brown fur. The downy-soft fur on its
under-belly is light gray. The muskrat has a roundish head,
with small ears almost hidden under its fur. Its eyes, ears, and
front feet are also very small. On the back feet, stiff hairs on
the side of each large toe spread out, overlapping the hairs from
the adjacent toes to act as webbing. This physical attribute
helps make the muskrat a strong swimmer.
The muskrat prefers wetland areas with a plentiful supply of
water plants for both food and lodging. What the animal does
not eat of a plant, it uses for home construction or lining the
cavities of its home. Muskrats build mound-like home of plant
materials in marshes or burrow into the bank of the river.
The muskrat eats bur-reed, spikerush, and other water plants. Its favorite food is the roots of these
plants, but it also eats the stems and leaves. In winter, when many roots are frozen, the muskrat eats
freshwater clams. A very hungry muskrat will eat a water insect, or even a crayfish or a snail, if it
cannot find roots or clams.
A young muskrat can become the prey of many larger animals. The importance of the young as a
food source is increased by prolific reproduction--three litters a year. The mink and the wolf are the
main predators of the adult.
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Eastern Gray Squirrel
The Eastern Gray Squirrel is a rodent with a large bushy tail. It lives
wherever there are nut trees such as oak, hickory, and beech. It may live in
a forest, suburban backyard or even a city park, as long as there are nut
trees. It spends much of its life in trees, running up and down trees, though
it does not range far from its home base. Squirrels build untidy nests of
twigs and dry leaves usually in the crooks of tall trees and live in loose
colonies. They are very active early in the day and again just before dusk.
Squirrels are called scatter-horders. They bury caches of nuts all
throughout their area to dig up later. This practice ensures a plentiful and
ready supply of food throughout the year, especially important through the winter. In addition to
nuts, squirrels eat seeds, bird seed set out by people, fungi, fruits, twigs and bark. It will even
supplement its diet with an occasional insect, bird egg, frog or lizard. Hawks, skunks, raccoons,
snakes and owls all eat squirrel. Because of its caches, squirrels are important tree planters. They
also eat so much plant material that they control plant populations.
Opossum
Opossum are cat sized mammals with grey to black fur, black eyes,
pointed nose with hairless, tail, ears, and toes. They are the only
marsupial in North America. They are nocturnal and solitary. They use
their tail and paws that are shaped like hands to grab things and climb up
and down trees. They live anywhere in the basin where there is water,
food, and shelter but prefer marshes, swamps, and streams. Opossum is
an omnivore and an important scavenger—it eats anything dead or alive.
It has a keen sense of smell which helps it find its food. Their favorite
food is an insect especially beetles but they also eat berries, fruits, bird
and snake eggs, rodents, grasses, and snails. They help control the
insect population and clean up dead matter in the river basin protecting
the oxygen supply. The opossum has many behavioral adaptations used
for protection. The most well-known is playing ‘possum, pretending to be dead until a predator
looses interest. It also drools to pretend to be sick and hisses and growls while bearing their many
teeth to look fierce. The main predator of the opossum is the wolf.
Raccoon
Raccoons are mammals noted for their flexible toes which
they use for grabbing things and climbing. They live in
wooded areas close to water usually in a den in a tree. They
have gray to brown fur, black mask of fur on the face
surrounded by white with a bushy ringed tail. Raccoons are
nocturnal. They hunt for their food under the cover of
darkness. They are omnivores and eat silky dogwood berries,
fruits, insects, eggs, small animals, nuts, frogs, crayfish, worms, snails, small fish, and clams. They
are good swimmers and often hunt for food in the water. Raccoons control animal populations in
the river basin system to help keep the system in balance. Opossum eat many dead animals
including raccoon. Raccoons have few predators, partly because they are active at night.
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Deer
The white-tailed deer, the one most commonly found in
northeast basins, are medium sized with gray-brown fur in
the fall and winter and reddish-brown fur in the spring and
summer. They have long legs with narrow hooves. Males
have branching antlers that they grow and shed annually.
Their young, fawns, are reddish-brown with white spots.
White-tailed deer live in field and forest edges and
woodlands with understory vegetation. They have few
natural predators which accounts for the increase in
population in recent decades. When they sense danger
their tail flips up and the white underside is shown as they
run away. This characteristic is where the common name white-tailed deer comes from.
They eat much vegetation, grasses, all types of nuts such as acorns and beech nuts, twigs,
and buds of all types of plants. Deer helps control the plant populations of a river basin
system.
Compiled by Pam Blair, August 1989;
ed. August 1990,
ed. AKW, March 2006
Senior Editor - Joy Shaw
Illustrations by Joy Shaw
3GM – 38
© 2006 Mill River Wetland Committee, Inc.
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