It's Earth Day. Here's what you should know about endangered and threatened species in Arizona

It's Earth Day, which is a good day to remind us that extinct is forever. Arizona is home to 43 endangered or threatened animal species, according to the U.S. Fish and Wildlife Service.

On the list

Here's a sampling of the endangered and threatened animals on the list: 

• The Mexican gray wolf. Endangered. Once hunted almost to extinction, conservationists and the federal government began reintroducing populations in eastern Arizona and western New Mexico about 20 years ago over the objections of ranchers, who feared economic losses from livestock predation. While the controversy continues, the population appears to be making a comeback.  
• The black-footed ferret. Endangered. The only ferret native to North America, the black-footed ferret is considered one of the most endangered mammals on the continent. While most have been wiped out by disease and loss of habitat, experimental efforts to reintroduce them in Arizona and elsewhere have been met with some success. 
• The Mexican spotted owl. Threatened. The largest owl in North America, the Mexican spotted owl is a sub-species of the spotted owl. The entire species became a symbol in the nation's ongoing debate of jobs vs. nature when a federal judge ruled that logging operations in the Pacific Northwest had to cease because of threat to the owl's habitat. The population is still declining and is protected in both the U.S. and Mexico. In 2004, the federal government declared 3.5 million acres of federal land in the Four Corners states (Arizona, New Mexico, Colorado and Utah) as critical habitat for the spotted owl.  
• Ridgenosed rattlesnake. Threatened. Found in the higher elevations of southeastern Arizona, southwestern New Mexico and northern Mexico, the snake is somewhat smaller than its cousins and is considered "elegant looking" by herpetologists. It's named for the distinctive crest on its nose. Its habitat is threatened by mining, cattle grazing and development. 
• Jaguars and ocelots. Endangered. The sleek and beautiful big cats once roamed freely throughout southern Arizona and northern Mexico but have been hunted to the brink of extinction, sometimes by farmers and ranchers in an effort to protect their livestock. Jaguars were thought to have become extinct in Arizona, but several sightings over the past few years have given conservationists hope that they can reestablish, but there are considerable concerns that a proposed border wall could keep that from happening. Ocelots are also endangered, though one was recently caught on a trail cam in Southern Arizona. 
• Sonoran tiger salamander. Endangered. Found primarily in ponds in the high grasslands of the San Rafael Valley (between the Patagonia and Huachuca mountains near the Mexican border in southern Arizona), the 3-6 inch long salamander needs standing water for up to six months for its jelly-coated eggs to grow into larvae. Its habitat is increasingly threatened because of natural predators as well as climate change. It has been listed as an endangered species since 1997. 
• Anything chub. Five species of chub fish, the bonytail, Gila, humpback, Virgin River and Yaqui chub are all listed as endangered. A sixth, the Sonoran, is threatened. Chub is a large classification in the family Cyprinidae, which includes carp and dozens of other species. 

MORE:Endangered Mexican gray wolf population increases, but questions linger about recovery progress

Not on the list

And a look at what's not on the list that might surprise you: 

• The saguaro. No, it's not an animal, but it's one of our state's most majestic symbols and is commonly thought to be among the 21 plant species that are endangered or threatened in Arizona. But the saguaro isn't on the list, at least not yet. The International Union for the Conservation of Nature, which publishes an annual Red List of threatened species, lists the saguaro as declining in population but lists it as a species of "least concern."  The biggest threats are development and climate change, but there are protections in place. It's illegal to cut down or remove a saguaro without a permit.  
• The Gila monster. Because it's rare to find a Gila monster in the wild, people assume they're endangered. That's not the case. The only poisonous lizard in Arizona much prefers to keep to itself, spending up to 95 percent of its time underground and only coming out to feed, which it doesn't do very often because it stores fat in its tail. The IUCN also lists Gila monsters, or beaded lizards, as a species of least concern, though it too has a declining population.  It is illegal to collect, kill or sell Gila monsters in Arizona. 
• Arizona bald eagle. In 1978 there were only 11 breeding pairs in the wild in all of Arizona. Today there are 69, and there were a record number of hatchlings this year. The regal symbols of our nation were on the endangered species list until 2007, but the Arizona population was relisted a year later and not removed until 2011. Conservationists argued that the Arizona bald eagle, which is somewhat smaller than those found elsewhere,  should be considered a separate sub-species because of its size and different habitat, but those arguments were rebuffed by the courts.  Bald eagles and their nesting areas are still protected by an array of federal and state laws. 

John D'Anna is a reporter on the Arizona Republic and azcentral.com storytelling team and a former environmental blogger, which explains his Twitter handle, @azgreenday. Reach him at john.danna@arizonarepublic.com. 

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