John hunted and captured live wild animals in the wildest parts of Maine, Vermont, and New Hampshire, where he honed his woodsman, survival, and marksmanship skills.
However, Adams told writer and historian Theodore H. Hittell, his early hunting and trapping career ended abruptly when he received severe back and spine injuries from a Bengal tiger he was attempting to train for his employers.
[16] In 1849 with the California Gold Rush in progress, John invested his life savings of over $6,000 (~$173,844 in 2023) to buy a large supply of footwear, and had it shipped to St. Louis, Missouri.
He knew even if he failed to recoup his lost investment in the mines, he could at least support himself by hunting and trapping in the untapped wilds of California.
On his journey via the Santa Fe and Gila trails, he twice survived near fatal illnesses and arrived at the gold fields of California late in 1849.
[18] Adams tried his luck at mining, hunting game to sell to the miners, trading, and finally, ranching and farming.
Late in 1852, having lost his ranch outside of Stockton, California, to creditors, he took the few items he could salvage and headed into the Sierra Nevada mountains to get away from it all.
[20] Adams traveled great distances from his California base camp on foot, on horse or mule, or in an ox-drawn wagon.
In 1853, he made a hunting and trapping expedition some 1,200 miles (1930 km) from his base camp in California to eastern Washington Territory (what is now western Montana).
In 1854, Adams retrieved a pair of two-week-old male grizzly cubs from the den of their mother near Yosemite Valley.
[34] The mating resulted in a male cub that was born the next year when she was with Adams in Corral Hollow on the eastern side of the California coastal mountains.
[39] Due to interest of the curious people the group met, John set up impromptu shows of his bears and other animals he had collected on his summer excursion.
[41] Due to notices T. H. Hittell printed in the San Francisco daily Evening Bulletin, Adams' show drew many more patrons.
[42] In January, 1858, tragedy struck when noble Ben, John's favorite grizzly, died of an illness for which no remedy could be found.
[44][45] On January 7, 1860, Adams and his menagerie departed from San Francisco on the clipper ship Golden Fleece on their way to New York City via Cape Horn, a 3+1⁄2-month voyage.
His health continued to decline and after a doctor told him he had better settle his affairs, Adams decided he would sell his menagerie to Barnum.
However, disregarding his doctor's prognosis, he managed to persuade Barnum to agree to let him perform his animals for another ten weeks for a $500 bonus.
[47] Adams suffered head and neck trauma during a grizzly attack in the Sierra Nevada mountains of California in 1855.
The damage was further exacerbated while Adams was on tour with a circus in New England during the summer of 1860, when a monkey he was attempting to train purportedly bit into the wound.
[48] After more than four months performing with his California Menagerie, complications from the injury led to Adams' inability to continue with the show.
After completing his contract with P. T. Barnum, he retired to Neponset, Massachusetts, where he died of illness (possibly meningitis) just five days after arriving at the home of his wife and daughter (October 25).
[55][56] Boston, Massachusetts was the venue for many such menageries while Adams was living there, so he had the opportunity to meet and interact with the proprietors and performers.
[64] Lee hired a man by the name of David Howard to run the ranch which was about eight miles (13 km) southeast of Stockton, on Mariposa road.
According to Williams[66] when Grizzly Adams established his Mountaineer Museum in San Francisco, in 1856, the menagerie was a part of Lee's Circus, as a side show.
On April 30, 1860, Adams and Barnum opened the California Menagerie in a canvas tent on the corner of Broadway and Fourth Street in New York City[69][70][71] The show ran for six weeks.
Richard Dillon considers him to be "the greatest California mountain man of them all",[78] and McCracken labels him the "Fabulous Mr. 'Grizzly' Adams.
On the East Coast, the Zoological Gardens in New York's Central Park was established in 1860 and in 1899 the Bronx Zoo was opened.
[84][85] Nahl's 1855 painting of a California grizzly portrayed Adams' bear Samson, which the mountain man had brought to San Jose and San Francisco to display that year; this image ended up being the source for the California Bear Flag, for which the official design specifications were put into law in 1953.
Although not educated as a naturalist in a college or university, Adams learned the habits and facts of grizzly life first-hand through his observations while hunting and trapping them.
[93] Adams was a famed United States outdoorsman, animal collector/trainer and an owner/performer in his own menagerie and later a partner of P. T. Barnum's shows.