Dolphins
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These Beautiful Gentle Creatures
Are Feared To Be Dying Out In Many Parts Of The World
Due To Pollution And Depressed Immune Systems Caused By It
Other Factors To Their Potential Demise
Are The Nets Used By Fisherman In Many Parts Of The World And Poaching
For More Than 30 Years
The International Tuna Industry Devastated The World's Dolphin Population
Pushing Some Species To The Brink Of Extinction
Over 6 Million Spinner
Spotted
And Common Dolphins
Were Killed When They Became Entrapped In Tuna Fishing Nets
A Massive Tuna Boycott By Angry Consumers In The United States
Led To A Major Victory "Dolphin Safe" Tuna On Grocery Store Shelves
Some Nations However Continue To Use Nets That Entrap Dolphins
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Dolphin Facts
To Breathe When They Are Asleep
Female Dolphins Lie On The Water's Surface With Their Blowholes Exposed To The Air
Males Sleep Just Below The Surface
Males Rise To Breathe Periodically As A Reflex Action
Dolphins Rest With One Eye Opened And The Other Eye Closed!
One Half Of Their Brain Shuts Down While They Are Sleeping
Dolphins Can Live Up To 50 Years
There Are Approximately 40 Species Of Dolphins And Porpoises
Dolphins Can Grow Up To 13 Feet In Length
Dolphins Can Weigh Up To 450 Pounds
Dolphins Can Stay Submerged For Up To 15 Minutes
Dolphins Can Dive To 1000 Feet
Dolphins Can Swim Substained Speeds Of 20 Mph...Burst Speeds Of Over 25 Mph
A Dolphin Has Special Structures In Its Skin
That Reduces Turbulence When Swimming At High Speeds
You Can Tell How Old A Dolphin Is By The Rings That Grow On The Root Of Its Teeth!
Each Growing Season The Pulp Cavity Fills In A Little Bit
By Taking A Small Piece Of This Section And Looking At It Under A Microscope
You Can Count The Rings Just Like On A Tree
Dolphins Are Meat Eaters With Over 200 Teeth
They Eat Mostly Fish And Can Eat Up To 1/3 Their Weight Each Day
Most Dolphins Locate Their Food By Emitting Clicking Sounds
Then They Listen For How The Sounds Bounce Off Objects
Dolphins Travel In Groups
Males Are Bulls
Females Are Cows
And The Young Are Calves
Because Of The Dolphin's Elongated Skull
One Could Think Of The Blow Hole As The Nostril
And The Melon Of The Dolphin To The Upper Lip In Humans
The Blow Hole Is Used In Much The Same Way But The Melon Is Not
The Melon Is Used As A Lens To Focus High-Pitched Clicks For Echolocation
Dolphins Can Produce Sound Frequencies From 0.25 To 200 kHz
The Higher Frequencies Are For Echolocation
The Lower Ones Are For Communication And Orientation
Dolphins Do Not Have Vocal Cords Like Humans
Their Vocalization Comes From The Sphincter Muscle In The Blow Hole
Dolphins Use Clicking Sounds Or Short Whistles
Which Are Really Short Pulses Of About 300 Sounds Per Second
This Enables A Dolphin To Navigate Among Its Companions And Larger Objects
These Sounds Are Also Used To
Communicate Alarm
Sexual Excitement
And Perhaps Other Emotional States
Male Dolphins Become Sexually Mature After 5 To 12 Years
Females Become Sexually Mature After 9 To 13 Years
Dolphins Mate In The Spring And Early Summer
The Pregnancy Last From 10 To 12 Months
The Females Almost Always Give Birth To One Baby At A Time
The Baby Is Called A Calf
The Calf Is Born Tail First And Immediately Swims To The Surface
Sometimes With The Mother's Help For It's First Breath Of Air
A Newborn Calf Is About A Third Long As Its Mother
Dolphin Calves Nurse Underwater And Close To The Surface
Female Dolphins Like All Mammals Have Special Glands That Produce Milk
The Milk A Female Dolphin Produces For Her Calf Is Made Up Of Approximately
33% Fat
6.8% Protein
58.3% Water
And Some Traces Of Lactose
The Calf Drinks The Milk From The Mother's Nipples
They Nurse And Protect Their Young For More Than A Year
The Male Takes No Part In Caring For The Young
Sometimes An Assisting Dolphin May Stay Close To The Mother And The Calf
This Is Uusually The Only Other Dolphin The Other Allows Close To Her Calf
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