Once the revered symbol of Thai culture, the backbone of industry and the protector of the country’s sovereignty during war, elephants now wander the streets of Bangkok, reduced to providing rides for tourists and helping their owners beg for their next meal.

With their drivers — mahouts, they are called — the elephants dodge Bangkok’s chaotic traffic and the feeble attempts of the government and the police to push them out of the city.

Many elephants were put out of work when logging became illegal in the 1980s, making it difficult for their owners to feed them. Wild ones have been hunted and driven from their natural habitat. It is estimated that there are now 2,500 domesticated and 1,500 wild elephants in Thailand, down from around 50,000 in 1950.

Some of their owners bring them to Bangkok so they can afford to feed and care for the elephants, who are treated like family. Other owners are more mercenary, keeping the beasts in squalid conditions and renting them to the highest bidder for tourist rides.

Pollution, traffic and noise make Bangkok inhospitable to elephants. Their presence is a source of controversy. Preservation and environmental organizations try to protect the elephants in a world where they have little utilitarian value. Some groups promote elephant riding.

The Canadian photographer Brent Lewin, 29, fell in love with elephants as a tourist in 2002, when he rode one while visiting a remote area in the north of Thailand. Before that, most of his interactions with large animals occurred at petting zoos.

Mr. Lewin, a contributing photographer at Redux Pictures, has been documenting the plight of Bangkok’s elephants since 2007. Though he’s only been photographing seriously for three years, he has made a series of elegant and elegiac images.

Pictures of elephants grace ancient temple walls and commercial billboards. They are a dearly loved symbol that is part of Thailand’s national narrative. Mr. Lewin wants the country to preserve and protect these living symbols of its heritage and history.

“In battle, the elephants helped protect Thailand from colonization,” Mr. Lewin said. “But now Thailand has been penetrated by the forces of globalization.”

“They fail to recognize that the elephant has fallen from grace.”