Spotted Jellyfish

The Spotted Jellyfish (Mastigias papua) can be found in warm coastal waters in the South Pacific, around Hawaii, and around Puerto Rico. It is commonly called the lagoon jelly.
It grows to about 5.5 inches and it feeds on zooplankton.

These jellies can be seen at these aquariums:

Hawaii region
Waikiki Aquarium  Honolulu, Hawaii

Pacific region
Vancouver Aquarium  Vancouver B.C., Canada
Monterey Bay Aquarium  Monterey, California

Eastern region
Mystic Marine Life Aquarium  Mystic, Connecticut

Sea Nettle

There are 12 valid subspecies of the Sea Nettle (Chrysaora fuscescens), and they are found in abundance in oceans all over the world. The two most known about are Chrysaora quinquecirrha which is found in the Atlantic waters along the East coast of North America, and the second most common (pictured here) is the Chrysaora fuscescens found along the West coast of North America in the north east Pacific.

Their 'bell' gets about 6 - 8 inches wide and their long tentacles enable them to eat much larger prey than most jellyfish species.
The 12 subspecies of Sea Nettle are:
Chrysaora achlyos
Chrysaora chinensis
Chrysaora colorata
Chrysaora fulgida
Chrysaora fuscescens
Chrysaora hysoscella
Chrysaora lactea
Chrysaora melanaster
Chrysaora pacifica
Chrysaora pentastoma
Chrysaora plocamia
Chrysaora quinquecirrha

Aquariums that these jellies can be seen at are:

Hawaii region
Waikiki Aquarium  Honolulu, Hawaii features the Atlantic Sea Nettle (Chrysaora quinquecirrha)

Pacific region
Vancouver Aquarium  Vancouver B.C., Canada
 Monterey Bay Aquarium  Monterey, California features the Black Sea Nettle (?)
Aquarium of the Bay  San Francisco, California features the Pacific Sea Nettle (Chrysaora pacifica)
Aquarium of the Pacific  Long Beach, California
The Birch Aquarium  La Jolla, California

Fried Egg Jellyfish

The Fried Egg Jelly (Cotylorhiza tuberculata) Ranges from Alaska to California, and in cold/ temperate waters around the world.
Not much to say, they look like a fried egg!

They can be seen at these aquariums:

Pacific region
Vancouver Aquarium   Vancouver B.C., Canada
 Monterey Bay Aquarium  Monterey, California

White spotted Bamboo shark

The White spotted Bamboo sharks (Chiloscyllium plagiosum) pictured above, are pups born at the Vancouver Aquarium in Vancouver B.C., Canada. They are a type of carpet shark and do not need to continue swimming to breathe, but can lay on the ocean floor for extended amounts of time.
Adults get up to 1 meter (3 feet) in length. They are nocturnal and are not a threat to humans. This species, however, is a near threatened animal.
They are found in coral reefs in the Pacific Ocean and are commonly found around Indonesia, but range from Japan to India.In Taiwan and Madagascar, they are consumed for food.
These sharks feed on small fish and invertebrates.

These sharks can be seen in these aquariums:

Pacific region
Vancouver Aquarium   Vancouver B.C., Canada
Aquarium of the Pacific  Long Beach, California

Eastern region
Mystic Aquarium  Mystic, Connecticut
Sea World Orlando  Orlando, Florida
  

Dwarf Crocodile

The Dwarf Crocodile (Osteolaemus tetraspis) is the smallest of the 'large' crocodile species.

It is considered a vulnerable species.
It has a fairly wide range, being found from sub-Saharan west Africa to west central Africa, and south to Angola.
It is a shy nocturnal crocodile that inhabits slow moving river waters, swamps and savanna water pools.

There are two known subspecies of Dwarf crocodile, they are:
Osteolaemus tetraspis tetraspis, and
Osteolaemus tetramus osborni- the Congo or Osborn's dwarf crocodile
There my also be a third, but that is still under speculation by the scientific community.

Other names that this animal goes by are:
African broad-nosed crocodile
African caiman
African dwarf crocodile
Black crocodile
Bony crocodile
Broad - snouted crocodile
Rough - backed crocodile
West African dwarf crocodile

Zoos they can be seen in are:

Pacific region
Woodland Park Zoo  Seattle, Washington
Sacramento Zoo  Sacramento, California
San Diego Zoo  San Diego, California

Mountain region
Wildlife World  Litchfield Park, Arizona

Central region
Lincoln Park Zoo  Chicago, Illinois

Eastern region
 
 

Sloth Bear

The Sloth Bear (Ursus ursinus) is also known as the Labiated Bear. It is considered a vulnerable species as it competes with humans for living space, and also has many predators in the animal kingdom. They are the most likely of all animals to make an unprovoked attack on humans.
They are a nocturnal insect eating machine. They prefer termites, honey bee colonies and fruit.
They can be found on the Indian subcontinent.

There are two subspecies of Sloth Bear, the Sri Lankan sloth bear ( Melursus ursinus inornatus) from the island of Sri Lanka, and the Common sloth bear (Melursus ursinus ursinus) found in India, Nepal, Bhutan, Bengladesh, and Pakistan.
It was thought, when the sloth bear was first discovered by the scientific community, that it was related to the tree dwelling sloth of South America, but it really has no relation to that species of animal.

 

Zoos that these bears can be seen in are:

Pacific region
Woodland park Zoo  Seattle, Washington

Mountain region
Tautphaus Park Zoo  Idaho Falls, Idaho
Zoo Boise  Boise, Idaho

Central region 
Sunset Zoo  Manhattan, Kansas
Montgomery Zoo  Montgomery, Alabama

Eastern Region
The Smithsonian National Zoo Washington D.C.
Lowry Park Zoo  Tampa, Florida features the Sri Lankan Sloth Bear (Melursus ursinus inornatus)
Miami Metro Zoo  Miami, Florida

Egyptian Tortoise

The Egyptian Tortoise (Testudo kleinmanni) is an African species of tortoise which is critically endangered due to over collecting for the pet trade. It is extinct in the country of Egypt in north east Africa.
Their range is from Lybia to places beyond the Nile Delta. They live on the northern coast of the African continent, in desert and semi-desert locations.
The Egyptian tortoise is also known as the Kleinmann's tortoise and sometimes the Leith's tortoise.
They are the smallest tortoise species in the northern hemisphere and the second smallest in the world, second only to South Africa's Speckled Padloper (Homopus signatus), which is also known as the Cape tortoise.

Zoos where they can be seen:

Pacific region
Woodland Park Zoo  Seattle, Washington 

Mountain region

Central region
Birmingham Zoo  Birmingham, Alabama

Eastern region
 

European Fallow Deer

The European Fallow Deer (Dama dama dama) was introduced through out Europe by the Romans for sport hunting. They are originally from Eurasia.
Only bucks (males) sport antlers.
They can run up to 30 miles per hour (48 km/h).
Their coloring is either a chestnut tan, black or Leucistic, that is white but not albino.

Zoos where they can be seen are:

Pacific region
Olympic Game Farm Sequim, Washington
Wildlife Safari Winston, Oregon


Mountain region
Willow Park Zoo  Logan, Utah
Grand Canyon Deer Park  Williams, Arizona

Central region
Roosevelt Park Zoo  Minot, North Dakota
Wild Animal Safari  Stratford, Missouri
Promise land Zoo  Eagle Rock, Missouri
Wild Wilderness Drive Through Safari  Gentry, Arkansas
Zoo of Acadiana  Broussard, Louisiana

Eastern region 
Cindy Lou's Zoo  Roscommon, Michigan
Black Pine Animal Sanctuary  Albion, Indiana
Noah's Lost Ark  Berlin Center, Ohio
Tennessee Safari Park  Alamo, Tennessee
Claws 'N Paws  Hamlin, Pennsylvania
Living Treasures Wild Animal Park  New Castle, Pennsylvania 
Long Island Game Farm  Long Island, New York
York's Wild Kingdom  York's Beach, Maine
Southwick's Zoo  Mendon, Massachusetts 
Space Farms Zoo  Sussex, New Jersey
Plumpton Park Zoo  Rising Sun, Maryland  
Luray Zoo  Luray, Virginia
Richmond Metro Zoo  Richmond, Virginia
Virginia Safari Park  Natural Bridge, Virginia 
Wild Animal Safari  Pine Mountain, Georgia
Brevard Zoo  Melbourne, Florida
Lion Country Safari  Loxahatchee, Florida

American Bison

The American Bison (Bison bison bison) is also known as the American Buffalo, although it is only a distant cousin to true buffalo. There are 2 subspecies of bison, with 3 total species altogether. The subspecies are Plains Bison (Bison bison bison) and Wood Bison (Bison bison athabascae). The third species of bison is the European bison, or Wisent (Bison bonasus).
Of the North American species, only the Wood Bison is considered endangered. A herd of 200 was found in 1957 in Alberta, Canada. They were thought to be extinct.
The Plains Bison was on the verge of extinction, but has been spared due to conservation efforts. This majestic animal is a truly American icon. It feed, housed and clothed the native Americans for centuries.
The Bison is the heaviest terrestrial mammal on the north American continent.
They swim well and are nomadic grazers, hence the name 'Plains Bison'.

Zoos where they can be seen are:

Alaska region
Reindeer Farm Palmer, Alaska

Pacific region
Greater Vancouver Zoo Aldergrove B.C., Canada
Olympic Game Farm Sequim, Washington
Northwest Trek Eatonville, Washington
Wildlife Safari Winston, Oregon
Moonridge Animal Park  Big Bear Lake, California features the Wood Bison (Bison bison athabascae)
Oakland Zoo  Oakland, California

Mountain region
Grand Canyon Deer Farm  Williams, Arizona
Denver Zoo  Denver, Colorado
Pueblo Zoo  Pueblo, Colorado 

Central region
Dakota Zoo  Bismarck, North Dakota
Roosevelt Park Zoo  Minot, North Dakota
Bear Country U.S.A.  Rapid City, South Dakota
Bramble Park Zoo  Watertown, South Dakota
Sedgwick County Zoo  Wichita, Kansas 
Amarillo Zoo  Amarillo, Texas
Caldwell Zoo  Tyler, Texas
Cameron Park Zoo  Waco, Texas
Minnesota Zoo  Apple Valley, Minnesota 
Wild Wilderness Drive Through Safari  Gentry, Arkansas
Baton Rouge Zoo  Baton Rouge, Louisiana 
Louisiana purchase Zoo  Monroe, Louisiana 
Henry Vilas Zoo  Madison, Wisconsin
Lincoln Park Zoo  Manitowoc, Wisconsin
Wildwood Park Zoo  Marshfield, Wisconsin 
Brookfield Zoo  Brookfield, Illinois
Wildlife Prairie State Park  Hanna City (Peoria), Illinois
Montgomery Zoo  Montgomery, Alabama

Eastern region
Garlyn Farm Zoo  Naubinway, Michigan
Columbus Zoo & Aquarium  Columbus, Ohio
The Wilds  Cumberland, Ohio
Tennessee Safari Park  Alamo, Tennessee 
Claws 'N Paws  Hamlin, Pennsylvania
Living Treasures Wild Animal Park  New Castle, Pennsylvania
Elmwood Park Zoo  Elmwood Park, Pennsylvania
Buffalo Zoo  Buffalo, New York
Bronx Zoo  New York, New York
Queens Zoo  New York, New York
Long Island Game Farm  New York, New York
Buttonwood Park Zoo  New Bedford, Massachusetts 
Roger Williams Park Zoo  Providence, Rhode Island
Space Farms Zoo  Sussex, New Jersey
Turtle back Zoo  West Orange/ Sussex, New Jersey
Salisbury Zoo  Salisbury, Maryland
The National Zoo  Washington D.C.
Virginia Zoo  Norfolk, Virginia
Richmond Metro Zoo  Richmond, Virginia 
Virginia Safari Park  Natural Bridge, Virginia
West Virginia Zoo  Kingwood, West Virginia
North Carolina Zoo  Asheboro, North Carolina
Chehaw Wild Animal Park  Chehaw, Georgia
Wild Animal Safari  Pine Mountain, Georgia 
Beardsley Zoo  Bridgeport, Connecticut

Yak

The Yak (Bos grunniens or Bos mutus) has been domesticated in its natural range for centuries. It serves as a beast of burden, is great for milk and its long thick wool is great for clothing, tent making, or any desirable use of woven material.
They range from the Himalayan region of south central Asia, the  Tibetan Plateau, and north to Mongolia and Russia.
They form herds of 10 - 30 minimally, but can be as large as several hundred. The wild yak avoids humans.

Zoos where they can be seen are:

Alaska region
Alaska Zoo Anchorage, Alaska 

Pacific region
Greater Vancouver Zoo Aldergrove B.C., Canada
Olympic Game Farm Sequim, Washington
Wildlife Safari Winston, Oregon

Mountain region
Tautphaus Park Zoo  Idaho Falls, Idaho

Central region
Wild Animal Safari  Stratford, Missouri
Promised land Zoo  Eagle Rock, Missouri
Wild Wilderness Drive Through Safari  Gentry, Arkansas

Eastern region 
Potter Park Zoo Lansing, Michigan
Living Treasures Wild Animal Park  New Castle, Pennsylvania
Southwick's Zoo  Mendon, Massachusetts
Space Farms Zoo  Sussex, New Jersey
Virginia Safari Park  Natural Bridge, Virginia
Luray Zoo  Luray, Virginia
North Georgia Zoo   Cleveland, Georgia
Wild Animal Safari  Pine Mountain, Georgia

Emerald tree boa

The Emerald tree boa (Corallus caninus) comes from South America. It spends its days hanging in the trees and vines of dense rain forests of Brazil, Suriname, French Guiana, Venezuela, Columbia, Guyana, Peru and Bolivia.
It is a night hunter and when it has captured its prey, it will hang up side down to swallow it.
The Emerald tree boa can reach about 6 feet in captivity and up to 9 feet in the Amazon basin.
Babies and juveniles start out a dark orange to brick red color, morphing into their beautiful shades of Emerald green in adulthood. These snakes have a row of white spots that are spaced apart, running the length of their back. Also, they have probably the longest front teeth of any non-venomous snake species.
They are from South America, and are not closely related to the Green tree Python (Morelia viridis) of New Guinea, Indonesia, and Cape York peninsula of Australia.

Zoos where they can be seen are:

Pacific region
The Reptile Zoo Monroe, Washington
Woodland Park Zoo Seattle, Washington
Point Defiance Zoo & Aquarium Tacoma, Washington
Oregon Zoo Portland, Oregon
Oakland Zoo  Oakland, California

Mountain region
Pueblo Zoo  Pueblo, Colorado 


Central region
Henry Doorly Zoo  Omaha, Nebraska
Oklahoma City Zoo  Oklahoma City, Oklahoma 
El Paso Zoo  El Paso, Texas
Dallas World Aquarium Dallas, Texas
St. Louis Zoo  St. Louis, Missouri
Birmingham Zoo  Birmingham, Alabama
Montgomery Zoo Montgomery, Alabama

Eastern region
Potter Park Zoo  Lansing, Michigan
Cleveland Metro Park Zoo Cleveland, Ohio  
Nashville Zoo  Nashville, Tennessee
Bronx Zoo  New York, New York
Central Park Zoo  New York, New York
Seneca Park Zoo  Rochester, New York
Zoo Atlanta Atlanta, Georgia 
The Georgia Aquarium  Atlanta, Georgia
Roger Williams Park Zoo  Providence, Rhode Island
Beardsley Zoo  Bridgeport, Connecticut
The National Aquarium  Baltimore, Maryland 
The National Aquarium  Washington D.C.
The National Zoo  Washington D.C.
Jacksonville Zoo  Jacksonville, Florida
Palm Beach Zoo  West Palm Beach, Florida

Giant African Millipede

The Giant African Millipede (Archispirostreptus gigas) is the largest species of millipede. They live in African rain forests, where they roam the forest floor searching out decaying vegetation to consume. Millipedes are none venomous, unlike centipedes which are carnivorous and will attack without provocation. There are over 10,000 species of millipedes in the world.
When threatened, the Giant Millipede will curl up into a spiral for self defense.

Zoos where they can be seen are:

Pacific region
Point Defiance Zoo & Aquarium  Tacoma, Washington
Oregon Zoo Portland, Oregon
Wildlife Safari Winston, Oregon
San Francisco Zoo  San Francisco, California
Oakland Zoo  Oakland, California
Santa Ana Zoo  Santa Ana, California
Charles Paddock Zoo  Atascadero, California

Mountain region
Cheyenne Mountain Zoo  Colorado Springs, Colorado

Central region
Sunset Zoo  Manhattan, Kansas
Dallas World Aquarium Dallas, Texas 
Brookfield Zoo  Brookfield, Illinois
St. Louis Zoo  St. Louis, Missouri
Baton Rouge Zoo  Baton Rouge, Louisiana 
Milwaukee County Zoo  Milwaukee, Wisconsin

Eastern region
Tennessee Aquarium  Chatanooga, Tennessee
Pittsburgh Zoo  Pittsburgh, Pennsylvania
Seneca Park Zoo  Rochester, New York
Central Florida Zoo  Sanford, Florida

Black tailed Prairie dog

The Black tailed Prairie dog (Cynomys ludovicianus) is the most common type of prairie dog. They are found all over the great plains of North America. Generally considered a nuisance by cattlemen and farmers, whose livestock would break legs after stepping in a burrow hole, or collapsing a prairie dog tunnel, are generally not a threat to humans at large. They fall prey to coyotes and various raptor species. Prairie dog towns, as they are called, can stretch for many miles and colonies of prairie dogs can reach several hundred or more.
There are 5 subspecies of prairie dog, of which 2 are endangered. The subspecies are:
 Black tailed Prairie dog (Cynomys ludovicianus) found throughout the great plains
White tailed Prairie dog (Cynomys leucurus) from Wyoming, western Colorado, eastern Utah, and southern Montana
Gunnison's Prairie dog (Cynomys gunnisoni) in the four corners region (southeast Utah, northeast Arizona, southwest Colorado, and northwest New Mexico)
Utah Prairie dog (Cynomys parvidens) in the south central steppes of Utah at about 3,300 feet
Mexican Prairie dog (Cynomys mexicanus) in rock free soil plains of south Coahuila and northern San Luis Potosi provinces in Northern Mexico
The Utah Prairie dog is the smallest subspecies of prairie dog and is endangered, as is the Mexican Prairie dog.
The Black tailed prairie dog does not hibernate like the other ones do. They are also active daily above ground, unless there is rain or snow, or temperatures exceeding 100 Fahrenheit.

Zoos where they can be seen are:

Pacific region
Olympic Game Farm Sequim, Washington
San Francisco Zoo  San Francisco, California
Los Angeles Zoo  Los Angeles, California
San Diego Zoo  San Diego, California

Mountain region
Zoo Boise  Boise, Idaho
Cheyenne Mountain Zoo  Colorado Springs, Colorado
Pueblo Zoo  Pueblo, Colorado
Arizona - Sonoran Desert Museum  Tucson, Arizona
Navajo National Zoo  Window Rock, Arizona

Central region
Dakota Zoo  Bismarck, North Dakota
Reptile Gardens  Rapid City, South Dakota 
Lincoln Children's Zoo  Lincoln, Nebraska
Minnesota Zoo  Apple Valley, Minnesota
Lake Superior Zoo  Duluth, Minnesota 
Henry Vilas Zoo  Madison, Wisconsin 
Lincoln Park Zoo  Manitowoc, Wisconsin
Wildwood Zoo Marshfield, Wisconsin
Milwaukee County Zoo  Milwaukee, Wisconsin
Sedgwick County Zoo  Wichita, Kansas
Sunset Zoo  Manhattan, Kansas
Tanganykia Wildlife Park  Goddard, Kansas 
Tulsa Zoo  Tulsa, Oklahoma 
El Paso Zoo  El Paso, Texas
Austin Zoo  Austin, Texas 
Fort Worth Zoo  Fort Worth, Texas
San Antonio Zoo San Antonio, Texas 
Blank Park Zoo  Des Moines, Iowa 
St. Louis Zoo  St. Louis, Missouri
Baton Rouge Zoo  Baton Rouge, Louisiana
Scovill Zoo  Decatur, Illinois
Wild Wilderness Drive Through Safari  Gentry, Arkansas 
Hattiesburg Zoo  Hattiesburg, Mississippi

Eastern region
Binder Park Zoo  Battle Creek, Michigan
Detroit Zoo  Detroit, Michigan
Saginaw Children's Zoo  Saginaw, Michigan
Fort Wayne Children's Zoo  Fort Wayne, Indiana
Masker Park Zoo  Evansville, Indiana
Potawatomi Zoo  South Bend, Indiana 
Memphis Zoo  Memphis, Tennessee
Columbus Zoo & Aquarium  Columbus, Ohio 
Claws 'N Paws  Hamlin, Pennsylvania
Elmwood Park Zoo  Elmwood Park, Pennsylvania
Philadelphia Zoo  Philadelphia, Pennsylvania
Zoo America North American Wildlife Park  Hershey, Pennsylvania
Prospect Park Zoo  New York, New York
Staten Island Zoo  New York, New York
York's Wild Kingdom  York's Beach, Maine 
Southwick's Zoo  Mendon, Massachusetts 
Cape May County Park & Zoo  Cape May Courthouse, New Jersey
Turtle back Zoo  West Orange/ Sussex, New Jersey
Maryland Zoo  Baltimore, Maryland
Salisbury Zoo  Salisbury, Maryland
The National Zoo  Washington D.C.
Virginia Zoo  Norfolk, Virginia
Richmond Metro Zoo  Richmond, Virginia
Mill Mountain Zoo  Roanoke, Virginia
West Virginia Zoo  Kingwood, West Virginia
Tregembo Animal Park  Wilmington, North Carolina

Kodkod cat

The Kodkod (Leopardus guigna) is one of the smallest feline species in the world and particularly the Americas. It is listed as vulnerable, therefore it is a very rare one indeed.They inhabit mostly temperate rainforests, coastal regions, scrub lands and thickets. They hunt at night, feeding on small insects, birds and rodents. There are two subspecies of Kodkod, also known as Guina (pronounced Hoo-ina). The subspecies are Leopardus guigna guigna found in Southern Chile and Argentina, and Leopardus guigna tigrillo found in central Chile.

Zoos where they can be seen are:
There are no zoos anywhere in the world that offer the Kodkod for viewing or breeding.

Vancouver Island Marmot

The Vancouver Island Marmot (Marmota vancouverensis) is indisputably North Americas rarest mammal and most endangered creature. Estimates are that there are less than 150 of these rodents left in the wild.When breeding programs were activated to increase their population, there were only about 30 in existence. They live in south to west facing meadows on Vancouver Island in British Columbia, Canada.

Zoos where they can be seen are:
Calgary Zoo Alberta, Canada

Moon Jellies

The Moon Jelly (Aurelia aurita) also goes by other names as well, such as common jellyfish and saucer jelly. They are found throughout the worlds oceans from tropics to cooler waters. They are quite prevalent.
Their common predators are Ocean Sunfish (Mola mola), Leatherback Sea turtle (Dremochelys coriacea), sea birds and other jellyfish species. Their life duration in the wild is about 6 months, but can live for many years in captivity.

Zoos and Aquariums where they can be seen are:

Hawaii region
Waikiki Aquarium  Honolulu, Hawaii

Pacific region
Vancouver Aquarium  Vancouver B.C., Canada
Seattle Aquarium  Seattle, Washington
Aquarium of the Coast  Newport, Oregon 
Aquarium of the Bay   San Francisco, California
Aquarium of the Pacific  Long Beach, California
The Birch Aquarium  La Jolla, California

Mountain region
Albuquerque Aquarium  Albuquerque, New Mexico

Central region
Henry Doorly Zoo  Omaha, Nebraska
Minnesota Sealife Aquarium  Bloomington, Minnesota
Dallas World Aquarium Dallas, Texas 
Houston Zoo  Houston, Texas
Milwaukee County Zoo  Milwaukee, Wisconsin

Eastern region
Fort Wayne Children's Zoo  Fort Wayne, Indiana
Newport Aquarium  Newport, Kentucky
Tennessee Aquarium  Chatanooga, Tennessee
Ripley's Aquarium of the Smokies  Gatlinburg, Tennessee
Akron Zoo  Akron, Ohio
Toledo Zoo  Toledo, Ohio
Long Island Aquarium  New York, New York
The New England Aquarium  Boston, Massachusetts
Mystic Marine life Aquarium  Mystic, Connecticut
Maritime Aquarium  Norwalk, Connecticut
The National Aquarium  Baltimore, Maryland 
The National Aquarium  Washington D.C. 
Virginia Living Museum  Newport News, Virginia
North Carolina Aquarium at Pine Knoll, North Carolina
South Carolina Aquarium  Charleston, South Carolina
Ripley's Aquarium at Myrtle Beach,  South Carolina
Key West Aquarium  Key West, Florida 

Northern Pacific Rattlesnake

The Northern Pacific Rattlesnake (Crotalus oreganus oreganus) is a pit viper with 7 other subspecies of pit viper found here in North America. The others that are related are:
Grand Canyon Rattlesnake (Crotalus oreganus abyssus)
Coronado Island Rattlesnake (Crotalus oreganus caliginis)
Arizona Black Rattlesnake (Crotalus oreganus cerberus)
Midget Faded Rattlesnake (Crotalus oreganus concolor)
Southern Pacific Rattlesnake (Crotalus oreganus helleri)
Great Basin Rattlesnake (Crotalus oreganus lutosus)
Northern Pacific Rattlesnake (Crotalus oreganus oreganus)
This family of rattlesnake can be found from British Columbia, Canada in the north, to New Mexico and through out the American southwest.
None are endangered.

Zoos where they can be seen are:

Pacific region
Woodland Park Zoo Seattle, Washington 
California Living Museum  Bakersfield, California
California Living Museum  Bakersfield, California also features the Southern Pacific Rattlesnake (Crotalus oreganus helleri)
Sacramento Zoo Sacramento, California

Mountain region
Heritage Park Zoo  Prescott, Arizona features the Arizona Black Rattlesnake (Crotalus oreganus cerberus)
The American International Rattlesnake Museum  Albuquerque, New Mexico  features the Arizona Black Rattlesnake (Crotalus oreganus cerberus)

Central region
St. Louis Zoo  St. Louis, Missouri  features the Grand Canyon Rattlesnake (Crotalus oreganus abyssus)

Eastern region

Common Chuckwalla & Gila Monster

The Common Chuckwalla (Sauromalus ater) shares some of the range with the Gila Monster (Heloderma suspectrum) in the South western portion of the United States, and the very North western portion of Sonora province of Mexico.
 There are 5 subspecies of Chuckwalla. They are Common Chuckwalla (Sauromalus ater)
                        Giant (Aka Painted, San Esteban Island) Chuckwalla (Sauromalus varius)
                                                               Angel Island Chuckwalla (Sauromalus hispidus)
                                                                 Peninsular Chuckwalla (Sauromalus australis)
                                                                    Monserrat Chuckwalla (Sauromalus slevini)
Of the 5, 2 are endangered, the Monserrat Chuckwalla, and San Esteban Island Chuckwalla.
The Common Chuckwalla can be found from Southern California east to southern Nevada, Utah and western Arizona, and south to Baja California and Northwestern Mexico.
They live in rocky areas and eat mostly vegetation and small insects.

The Gila Monster (Heloderma suspectrum) is one of two venomous lizard species in the world. Its cousin, the Mexican Beaded Lizard (Heloderma horridum) is the other.
There are two subspecies of Gila Monster, the Reticulated Gila Monster (Heloderma suspectum suspectum) and the Banded Gila Monster (Heloderma suspectum cinctum)
Reticulated is predominately the southern species, while Banded are the northern being found mostly in the Mojave Desert.
Gila Monsters can be found in Northern Arizona, California, Nevada, Utah, and New Mexico. They are not found in Baja, however.
They live in scrub lands, desert, and woodland areas and avoid open areas. They enjoy water as well, and can be seen in small pools after it rains.
The venom that these lizards have, is a neurotoxin, similar to that of a Coral snake (Micrurus family). The Gila Monster is a quick biter, but not a powerful one. They grind their venom into their prey. The venom gland in a Gila Monster is located in the lower jaw, unlike venomous snakes with the gland in the upper jaw.

Zoos where the Gila Monster can be seen are:

Pacific region
Woodland Park Zoo Seattle, Washington
California Living Museum  Bakersfield, California
Oakland Zoo  Oakland, California
Sacramento Zoo  Sacramento, California
Charles Paddock Zoo  Atascadero, California

Mountain region
Zoo Boise  Boise, Idaho
Hogle Zoo  Salt Lake City, Utah 
Heritage Park Zoo  Prescott, Arizona
Wildlife World  Litchfield Park, Arizona 
Arizona - Sonoran Desert Museum  Tucson, Arizona
Navajo Natonal Zoo  Window Rock, Arizona
Pueblo Zoo  Pueblo, Colorado
American International Rattlesnake Museum  Albuquerque, New Mexico

Central region
Reptile Garden  Rapid City, South Dakota
Lincoln (Folsom) Children's Zoo Lincoln, Nebraska
Oklahoma City Zoo  Oklahoma City, Oklahoma 
Gladys Porter Zoo  Brownsville, Texas
Lake Superior Zoo  Duluth, Minnesota
St. Louis Zoo  St. Louis, Missouri 
Henry Vilas Zoo  Madison, Wisconsin
Glen Oak Zoo  Peoria, Illinois
Birmingham Zoo  Birmingham, Alabama

Eastern region
Potter Park Zoo  Lansing, Michigan
Louisville Zoo  Louisville, Kentucky 
Memphis Zoo  Memphis, Tennessee
Nashville Zoo  Nashville, Tennessee
Cincinnati Zoo  Cincinnati, Ohio
Columbus Zoo & Aquarium  Columbus, Ohio
Toledo Zoo  Toledo, Ohio 
Philadelphia Zoo  Philadelphia, Pennsylvania
Pittsburgh Zoo  Pittsburgh, Pennsylvania
Zoo America North American Wildlife Park  Hershey, Pennsylvania
Ross Park Zoo  Binghamton, New York
Buffalo Zoo  Buffalo, New York 
Seneca Park Zoo  Rochester, New York
Utica Zoo  Utica, New York
Turtle back Zoo  West Orange/ Sussex, New Jersey 
National Zoo Washington D.C.
North Carolina Zoo  Asheboro, North Carolina
Tregembo Animal Park  Wilmington, North Carolina
Zoo Atlanta Atlanta, Georgia
Naples Zoo  Naples, Florida
Central Florida Zoo  Sanford, Florida


Zoos where the Common Chuckwalla can be seen are:

Pacific region
Woodland Park Zoo  Seattle, Washington
California Living Museum  Bakersfieled, California 
Oakland Zoo  Oakland, California
The Living Desert  Palm Desert/ Indian Wells, California

Mountain region
Hogle Zoo  Salt Lake City, Utah
The Arizona - Sonora Desert Museum also features the San Esteban Island Chuckwalla (Sauromalus varius)
Navajo National Zoo  Window Rock, Arizona
Pueblo Zoo  Pueblo, Colorado
Pueblo Zoo also features the San Esteban Island/Painted Chuckwalla (Sauromalus varius)

Central region
Oklahoma City Zoo  Oklahoma City, Oklahoma also features the San Esteban Island/ Painted Chuckwalla (Sauromalus varius)
Amarillo Zoo  Amarillo, Texas
St. Louis Zoo  St. Louis, Missouri
Milwaukee County Zoo  Milwaukee, Wisconsin  features the San Esteban Island/ Painted Chuckwalla (Sauromalus varius) 

Eastern region 
Potter Park Zoo  Lansing, Michigan
Louisville Zoo  Louisville, Kentucky
Buffalo Zoo  Buffalo, New York
Rosamond Gifford Zoo  Syracuse, New York 
Elmwood Park Zoo  Elmwood, Pennsylvania
Zoo America North America Wildlife Park  Hershey, Pennsylvania