Beaver
   
Castor  canadensis
   
NATURE'S  BUILDER
NATURE'S  CONSTRUCTION  ENGINEER
   
    SCIENTIFIC  CLASSIFICATION
    KINGDOM :              Animal
    SUB KINGDOM :     Metazoa
    PHYLUM :                Chordata
    CLASS :                   Mammalia
    ORDER :                  Rodentia
    FAMILY :                  Castoridae
    GENUS :                  Castor
    SPECIES :               canadensis
    *******************************************************************************************************************
    to learn about SCIENTIFIC CLASSIFICATION ..
    go to ..
    LINNAEUS SYSTEM OF CLASSIFICATION page
 
" God created every living thing. "
Genesis 1:21

    HELPFUL  INFORMATION


    BEAVERS ARE LARGE AQUATIC MAMMALS


    BEAVERS ARE BELIEVED TO BE RODENTS

    BEAVERS HAVE ALL THE CRITERIA TO BE RODENTS

    2 MATCHING PAIRS OF INCISORS AT FRONT OF JAWS
    GAP ON SIDES OF INCISORS
    OVER SIZED MUSCLES IN MOUTH TO AID IN GNAWING


    THERE ARE 2,000 KNOWN SPECIES OF RODENTS IN THE WORLD
    AT LEASE 40 % OF ALL KNOWN MAMMALS ARE RODENTS

    ONE OF SMALLEST RODENTS
    EURASIAN HARVEST MOUSE
    .14 OF ONE OUNCE
    ( .50 is 1/2 .. half of the ounce --  .25 is 1/4 .. quarter of the ounce --  .14 is a little more than 1/8 .. eighth of the ounce )




    LARGEST RODENT
    SOUTH AMERICAN CAPYBARA
    MORE THAN 100 POUNDS







    BEAVERS ARE THE 2ND LARGEST RODENT IN THE WORLD
    BEAVERS ARE THE LARGEST RODENT IN NORTH AMERICA


    THERE ARE 2 SPECIES OF BEAVER IN THE WORLD
    1 IN NORTH AMERICA
    Castor canadensis

    1 IN EUROPE
    Castor fiber
 

    BIOLOGY
    physical characteristics

    COLOR
    beavers can be all sorts of colors
    brown .. dark brown .. red .. golden .. black .. white .. silver .. albino
    most beavers are usually brown in color
    both male are female have same body coloration
    no difference

    SIZE
    large animal
    25 - 30 inches long not including tail
    45 - 90 pounds
    can weigh up to 100 pounds

    SHAPE
    rounded
    streamlined
    aerodynamic
    shaped like a seal
    body shape helps the beaver to move fast in the water !

    FUR
    super shiny
    thick thick thick
    looks black when wet
    2 kinds of fur
    undercoat  
    short soft underfur
    lighter in color - grey
    inner coat hairs have tiny scales on shafts .. scales cling to each other .. create air pockets
    traps air and keeps it close to skin for warmth .. even in icy water
    keeps them comfortable in water
    outercoat
    long heavy outer guard hairs on top of underfur
    protect underfur
    guard hairs define the color of the beaver
    shed outer coat every year
    called molting


    HEAD
    rounded head shape
    reduces drag in water      ( drag is the force of resistance against the beaver as it moves through the water )

    EYES
    small
    dark
    shiny
    great vision .. super great at close distances
    3 eyelids on each eye
    2 outer lids close when blinking and sleeping
    1 inner lid slides across over eye .. from inside corner outward to outer corner of eye ..
    transparent .. called nictitating membrane .. protects eyes underwater and when cutting wood
    NATURE'S OWN SAFETY GOGGLES !!!

    EARS
    small
    round
    furry
    super excellent hearing
    detect sounds in air and water

    have skin flap valve in each ear .. closes underwater .. keeps water out .. lets sound in

    NOSE
    large
    dark
    area around velvety

    super excellent sense of smell
    nose has internal skin flap valves .. keeps water out of nose when underwater

    MOUTH
    beaver's 4 inch incisor teeth are located in front of lips  .. only about 1" is visible above the gum line
    lips very furry
    lips have flap that closes behind incisors .. their lips are divided in the middle ..
    this is how beavers can hold wood in their mouths underwater
    and not get water into mouths at same time

    large powerful jaws

    beavers have special adaptation to eat and breathe at same time
    separate passage from nose to lungs
    separate passage from mouth to esophagus
    so they can chew and swallow at same time as breathing
    both actions are completely separate
    all of this is to keep water out of lungs

    TEETH
    use super amazing and strong teeth as tools
    front incisors grow throughout life
    used to cut and gnaw trees
    in just a couple of minutes a beaver can gnaw through a tree trunk with a 6 inch diameter !

    super sharp front teeth also used as weapons of self defense

    grinding teeth on sides of mouth to chew
    these cheek molar teeth do not grow in the same way
    as the incisor front teeth do ..
    cementum is added to surface of the enamel of the cheek teeth continually and that strengthens those teeth

    adult beavers have 20 teeth
    10 teeth in each jaw
    8 molars
    2 incisors

    orange layer on front teeth is super hard enamel - iron in their teeth gives orange color and super strength


    PAWS
    FRONT PAW HANDS
    front paws are very dexterous
    3 inches long
    3 inches wide
    look like small human hands
    first finger acts like opposable thumb to grip
    claws 1 inch long
    pointed

    sometimes when swim
    make tight fists with front paws and hold arms and paws close to chest against chest

    BACK PAW FEET
    back feet
    large
    7 inches long
    5 inches wide
    very long toes
    5 toes on each foot
    claw nails shorter than on front paws
    4 single claws on each foot
    1 split claw on each foot  - 2nd toe in from inside of each foot - like the 2nd toe on human foot next to big toe
    split claw has slit in middle
    used as comb to clean fur

    strong durable claws
    back feet used for excavation

    back feet used like flippers when swim


    GLANDS
    2 glands called castor glands
    secrete strong smelling liquid called castoreum
    located near base of tail
    both male and female have these glands
    secrete castoreum through skin ..
    use castoreum as grooming agent for fur ..
    beavers bring tail forward under body and sit on tail
    then collect oil in front paws and spread through fur
    oil keeps fur waterproof
    groom their fur everyday

    TAIL
    paddle shaped
    large
    broad
    flat
    used like rudder when swimming
    continues to grow entire lifetime .. in length and width .. not a lot .. but it really does grow !!!
    body fur covers about 1/4 of tail
    rest of tail has few sparse hairs
    tail has leathery dark skin
    tail has scale shaped PATTERN of ridges
    BEAVER TAIL DOES NOT HAVE SCALES   ! ! !

    tail helps control body temperature ..
    if beaver too hot .. heat will radiate out of tail to cool beaver
    if temperature outside too cold .. tail will hold heat in
    network of blood vessels in tail is how body temperature is regulated
    when blood vessels dilate .. heat goes out
    when blood vessels constrict .. heat stays in

    uses tail as prop for support when beaver ..
    stands up to eat bark from tree
    when cut tree
    when walking upright

    use tail as communication tool

    BEAVER TAIL IS USED FOR CONSTRUCTION  ! ! ! but not as a trowel .. is used as a support device

    caudal vertebrae that run down middle of tail are extension of spine

    fat stored in tail .. so tail can become whole lot thicker
    when food is scarce the tail fat is used as source of nutrients that the body draws upon


    SWIMMING
    super fantastic swimmers
    only whales and seals are better swimmers
    beavers swim 6 miles per hour
    beavers have a valve called the cloaca that keeps water out of ano-urinogenital openings
    ( these are the openings for the elimination of digestive wastes and for reproduction )

    beaver can travel 1/2 mile before surfacing for air

    when the outside temperature is cold ..
    before beavers go into the water they raise their body temperature by about 1- 2 degrees Fahrenheit
    this keeps them warm in very cold water

    when dive into water heart rate slows .. so use less oxygen
    when breathe .. at least 75% of air in lungs is exchanged for new and fresh air
    humans exchange  10 - 15 % of air in lungs


    BEAVERS ARE SUCH AMAZING ANIMALS !
    just their physical characteristics alone are incredible !!!
    but the things that they DO are even more amazing !!!!





    DIAMETER :
    the length of a straight line
    through the center of an object
    from one side edge to the other side edge
 
 

    LIFESPAN

    THE NORTH AMERICAN BEAVER LIVES UP TO 20 YEARS  !
 

    WHERE  IN  THE  WORLD

    BEAVERS LIVE ALL OVER NORTH AMERICA
    NORTH AMERICA TO ARCTIC EDGE
    SOUTH TO NORTHERN MEXICO

    EXCEPT
    EXTREME NORTH OF MIDDLE CANADA
    SOUTHERN CALIFORNIA
    MOST OF NEVADA
    MOST OF ARIZONA
    NORTHWESTERN TEXAS
    SOUTHERN PENINSULA PART OF FLORIDA
    COASTAL PANHANDLE PART OF FLORIDA
    MISSISSIPPI DELTA REGION   (their range ends 50 - 100 miles from the shore)

    BEAVERS ARE SO INTELLIGENT THAT THEY KNOW TO AVOID THE HURRICANE ZONE !!!
    NO BEAVER WOULD BUILD IN THE HURRICANE ZONE ..
    THEY ARE SO AMAZING !!!!
 

    HABITAT

    alpine meadows
    tundra
    mountains
    lowlands

    elevations from sea level to 10,000 feet

    prefer slow moving
    rivers
    streams
    lakes
    ponds

    need water source to be within nearby woodlands
    prefer abundance of aspen trees

    can use small creeks .. all the way up to large rivers .. including the MISSISSIPPI RIVER

    the territory of a CLAN of beavers is between 10 - 75 acres

    BEAVERS MAY TRAVEL 1/2 MILE AWAY FOR FOOD OR BUILDING MATERIALS IF THEY NEED TO

    THE AREA IN WHICH BEAVERS WILL GET FOOD SUPPLIES AND BUILDING SUPPLIES
    IS WITHIN A FEW HUNDRED YARDS  ( usually within 300 yards )  OF THEIR LODGE


    BEAVERS ACTUALLY CONSTRUCT THEIR HABITAT    !!!
    THERE ARE SEVERAL SPECIFIC STEPS OR STAGES THAT BEAVERS HAVE TO ACCOMPLISH TO COMPLETE
    CONSTRUCTION OF THEIR HABITAT

    1.  SCOUT FOR NEW HOME BUILDING SITE
    2.  GATHER CONSTRUCTION BUILDING MATERIALS
    3.  CONSTRUCT DAM / CREATE POND
    4.  CONSTRUCT BANK DEN
    5.  CREATE TRAILS
    6.  CREATE CANALS / CHANNELS AND LOCKS
    7.  CREATE TUNNELS
    8.  CONSTRUCT LODGE

    first they scout out just the right place .. slow water .. plenty of good trees that they like right around the water

    if lake .. do not need dam ..




    DAM
    usually only dam if .. river .. stream .. lake outlet ..

    BEAVERS BUILD DAMS SO THEY CAN CREATE
    THEIR BEAVER POND HABITAT
    THEIR LODGE HOME IN THE MIDDLE OF THEIR CREATED BEAVER POND

    how build ..
    usually select site for dam that is downhill from food sources and building material sources
    then ..
    build at shallow point of water source - in center of area to dam - build outward on each side towards banks
    mud stones piled up on water bottom .. in middle of water ..
    then ..
    add poles - poles are pushed down into the water bottom
    poles go in with tips leaning in same direction that water is flowing
    then ..
    pack with more mud and stones ..
    bring from water bottom with paws holding the mud and stones close to chest
    also adding brush and twigs ..

    top of dam above water

    can be 1,000 feet long  ! ! !
    sometimes more than one beaver family works on dam

    materials used ..
    usually begin with willows
    use lots of alders
    (bark has been peeled off of all construction pieces)
    rocks
    stones
    (weighing up to 40 pounds)
    mud

    beavers wil add all sorts of found items ..
    cans . bottles . balls . tires . cups . corn stalks .

    DAM  FACTS ..
    2 beavers can build small dam in 24 hours
    large dam in 3 - 4 nights
    water rises behind dam 3 - 7 feet
    a tiny current of water goes over the central outlet of the dam
    there are spaces underwater where fish can go through
    typical dam 75 feet long
    5 feet wide
    2 - 10 feet tall
    use hundreds of saplings to construct
    flat on top
    all sorts of animals use like bridge

    one of biggest dams in world is on the BOW RIVER in SASKATCHEWAN CANADA
    5,000 feet long .. almost 1 mile ! ! ! wow !!!!!

    largest dam in the United States is on the JEFFERSON RIVER in MONTANA
    2,300 feet long  ! ! !
    this dam is so strong that a human on horseback could ride across it !!!

    dams used and repaired for many years .. some are HUNDREDS of years old !!!
    FEMALE BEAVER IS THE DOMINANT BEAVER OF THE CLAN
    she directs the construction
    and
    the females of the clan do most of the actual construction
    BEAVER DAMS ARE SO COMPLEX - NO HUMAN ENGINEER COULD DUPLICATE  ! !
    dams are not watertight ... underwater there are openings ..
    a steady flow of water continues to travel through
    beavers do not interfere with fish spawning runs ..
    even large salmon and trout get through the openings and travel upstream to spawn  
    if damage to dam .. beavers immediately respond and repair damage
    will even come out during day to fix !
    beavers build larger constructions than any animals in North America ..
    except humans

    beavers tether all sorts of sticks and branches close to dam to be used as repair materials
    so they can make immediate repairs !
    beavers do not like gushing water .. they will try to stop it up !!!
    new dams easy to notice ..
    old dams NOT .. well camouflaged because all sorts of plants grow on them ..
    birds drop seeds and they sprout and grow ..
    cut construction branches take root and sprout and grow !
    most dam work is done in fall .. to get SUPER ready for winter !




    BANK DEN
    built in bank of river stream creek
    build at same time build dam so they can get to safety until lodge is finished
    then use the dens as secondary lodges for safety
    dig out den .. dig an entrance / exit  below surface of water
    sometimes pile sticks twigs branches mud on top for safety - also camouflages their air vents

    inside bank den ..  same size as lodge inside
    can use only a bank den if river is large and fast moving
    also called hut or hut lodge




    TRAILS
    make trails from water edge up into forest
    nip and trim the plants shrubs to keep trails clean
    about 15 - 20 inches wide
    may be 100 yards
    go to feeding areas - where they cut down small trees and bring the trees to the water to eat




    CANALS  /  CHANNEL and LOCKS  /  MINI DAMS
    beavers build all sorts of structures to
    control water flow
    control water level  
    channels act as drainage ditch if water level of pond gets too high
    move logs down to pond
    channel system moves logs easily to where they are needed
    12 - 18 inches deep
    18 - 24 inches wide
    may be 700 feet or more long




    TUNNELS
    make safety tunnels so they can stay in water as much as possible while moving from place to place
    make tunnels from tree supply areas to pond




    POND
    created as result of building dam
    created on the upstream side of the dam
    pond is really ..
    defensive MOAT
    safe water travel route to food
    safe water travel route to building materials

    saves time for beavers too !!
    faster in water than on land !!
    as beavers use mud for the dam and lodge construction they dig out the bottom of the pond area
    and
    this makes the pond area deeper !

    pond must be at least 3 feet deep for lodge building to begin

    usually ponds are about 4 - 6 feet deep

    POND FACTS ..
    winter .. pond freezes .. sometimes ice layer 2 feet thick .. no predators can get to lodge ..
    water level of area around pond rises after pond is created ..
    so .. the entire area is more resistant to FIRE !    WOW !!!!




    LODGE
    takes about 6 months to build at leisurely pace
    can complete in 30 days if rushed by oncoming winter
    inside ..
    4 - 8 feet diameter
    3 - 4 feet height
    floor 4 - 6 inches above water

    2 underwater entrances / exits ..
    1 to pull in timber and supplies
    1 for beavers to go in and out

    top of lodge is woven thatch
    vent holes between branches in ceiling to let in fresh air
    but constructed at angles in such a way .. no rain or snow gets in  !! !
    walls 10 inches thick
    plaster with mud inside
    freezes hard and solid
    all smooth inside

    looks like a tepee
    usually 3 - 6 feet above water

    beavers live inside these complex structures as their homes
    complex multi-level
    sometimes in middle of pond
    like island in middle of pond
    most often build on north or northwest side of pond
    building there allows for more sun .. and faster melting of ice in spring
    build lodges so they will have a permanent home in which to ..
    stay warm and dry
    sleep
    eat
    raise their families
    be safe

    materials used ..
    logs .. large tree wood -  4 - 5 feet lengths
    sticks
    branches
    twigs
    ( willow and alder .. the best )
    mud
    rocks
    stones ( up to 40 pounds )      WOW !!!

    add all sorts of things to lodges
    cans . bottles . tires . balls . cups . corn stalks

    how build ..
    use peeled sticks ..
    build platform to support internal chambers
    put log poles into pond bottom - dig out holes for log poles to be inserted
    lay more sticks into those - across
    pack with .. mud .. leaves .. rocks ..
    layer with more sticks twigs
    repeat until platform top layer is above water
    flatten top layer
    this top layer will become floor inside lodge
    then ..
    lighter layer of brush sticks small logs piled on creates dome shape above water
    next ..
    beavers nip and cut and trim branches to create tunnel entrances / exits
    then beavers excavate 2 tunnels through mud underwater up into lodge mound
    next ..
    chew out chamber inside mound
    chamber becomes beaver's living areas
    create second floor sleeping chamber  .. with .. mud .. sticks .. leaves
    walls of tunnels and chambers are plastered smooth with mud and leaves and twigs
    do not plaster very top of chamber
    this allows for ventilation

    LODGE FACTS ..
    carry mud rocks vegetation in front paws while walking upright with partial support from tails

    may build summer lodge and winter lodge

    lodge usually 20 feet along bottom of pond
    usually 10 feet from pond bottom to top lodge dome
    6 - 11 feet across above water
    3 - 6 feet tall above water

    external lodge wall very very thick and strong !
    first level inside 3 - 5 inches above water -- for eating -- grooming
    second level quite a bit higher -- for sleeping

    so warm inside .. in winter .. that steam rises from ventilation holes - looks like they have a fireplace !
    always repairing .. take super great care of lodge !

    use bedding in sleeping chamber
    finely shredded soft strips of wood
    usually willow
    every day replace their used bedding with FRESH BEDDING !!!
    more sanitary than many many many humans !!

    beavers used to build HUGE multi-family lodges
    with as many as 30 families in one colony
    each family had a separate lodge apartment
    all of these apartments were attached to each other !!
    creating HUGE HUGE HUGE lodges !!!!
    built these until European colonists came to North America
    beavers changed then to smaller lodges for safety ...
    less obvious to super dangerous dangerous dangerous humans ..
    more easily camouflaged ..



    TO CUT A TREE
    beaver stands on hind legs .. uses tail for support .. places front paws on trunk ..
    turns head sideways ..
    then ..
    bites trunk .. makes cut .. then .. bites trunk further down towards ground ..

    bite marks are always two together .. about 7/8 wide or wider ..
    distance between two bites depends on size of tree ..
    big tree .. first two bite cuts are further apart
    small tree .. first two bites are close to each other .. about 3 inches apart
    then ..
    bites a few more times to the two original bites to make deeper
    pulls off wood between with teeth .. and repeats process ..

    around base of tree collects pile of wood chips !

    usually cuts and tears wood all around trunk until it falls ..
    or may just cut and tear from one side until close to falling ..
    then ..
    push with head nose feet shoulder ... push .. usually falls towards water  ! ! !
    gravity takes over and CRACK   !!!!    CRASH  !!!!  and down it falls  !!!
    both tree and trunk stump that will remain are gnawed to a point ..
    beaver usually jumps into water as tree falls ..
    and then ..
    makes sure no predator was attracted by noise ..
    then ..
    goes to work on fallen tree ..
    gnaws off branches .. carries pushes pulls rolls cut logs into water
    usually one beaver does this job alone ..
    others working on other projects
 
 
 
 
" LORD,
You satisfy every living thing.
"
Psalm 145:14,16
 
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