For the last six months, Troy Barmore has left a precious keepsake at home in Brooklyn when he rides the subway into Manhattan — a stainless steel Rolex Submariner watch that once belonged to his father and was passed along to him as a college graduation gift.

“I outright stopped wearing it on the subway,” he said, “not because of any specific incident per se, just because of a general feeling of, ‘I don’t want to draw attention to myself in that way.’”

Now Mr. Barmore, the communications manager for the RedBar Group, a watch collectors’ organization, usually wears one of his less expensive timepieces, like a stainless steel Brew Watch Co. chronograph that retails for $375. It exemplifies what he called “a sweet spot” that he said many collectors are looking for at the moment: a timepiece that is well designed, but, as he put it, is “less noticeable, less risky in certain environments, less ostentatious.”

For years, stories about street robberies in the affluent neighborhoods of cities like London and New York — as well as ritzy holiday destinations, like Ibiza and the South of France — have circulated among watch collectors. The thieves, often armed, frequently speed away on mo-peds or scooters with the stolen goods.

“Everybody who’s paying attention has some degree of concern about that,” Mr. Barmore said.

Many watch owners insure their precious timepieces, but there’s also anxiety, in addition to loss, about potentially becoming the victim of a violent robbery.

But recently, as pandemic restrictions have eased in many areas of the world and travel has resumed, police departments are reporting a rise in this kind of crime.

According to the Los Angeles County Sheriff’s Department, there were 112 thefts involving at least one watch valued at $5,000 or more in the first six months of 2022, an increase of nearly 50 percent from the 75 thefts recorded in the same period in 2021.

And in London, the Metropolitan Police appealed to the public last month for help in catching watch thieves. The police reported there had been 67 watch thefts in central London between May 31 and June 27, an increase of roughly 60 percent in the previous four weeks’ total — and described incidents like a midmorning robbery in the Chelsea area in which a machete-wielding thief on a mo-ped forced a couple to surrender their watches, an Audemars Piguet and a Patek Philippe.

A few years ago Ashkan Baghestani, an art dealer, was chased by a man with a knife in Chelsea, and that was only about a week, he said, after a friend’s Rolex had been stolen in the area, too.

He decided to buy a dark green Cartier Tank watch late last year, around the time he moved to New York City. “That’s the only watch I’m comfortable wearing,” he said. “I’m not wearing a watch that’s worth more than $5,000.”

And Timm Golueke, a Munich-based dermatologist and founder of Royal Fern Skincare, said tales about friends’ watches being stolen had made him decide that he would never bring any of the valuable watches in his collection, like a Rolex Explorer, along on his frequent travels. Recently, he said, he has been wearing an Apple Watch because it makes him “feel better and more relaxed.”

This time of year — the season of short-sleeved shirts and sleeveless dresses (at least in the Northern Hemisphere) — watches are essentially on show. “Once you put that shiny, bright Franck Muller, Breitling, Rolex — whatever it is that’s on your wrist — you’re going to attract attention,” said Stephen Helliwell, director of operations at Aldermans Security Consultants, a British company that works primarily with celebrities and high net worth individuals.

Inevitably, the brands that are most coveted by collectors are also robbers’ favorites.

“If someone wants to steal a watch, they want to make sure that they’ll be able to sell it on black market pretty simply, so bigger name brands oftentimes are subject to a lot of these instances,” said Marc Hajjar, the director of Hodinkee Insurance, which was introduced by the watch-focused website in 2020. “The watches that are the most recognizable, the watches that are the most in demand, oftentimes are the ones that fall victim.”

Echoing Mr. Helliwell, Mr. Hajjar’s advice was to wear a watch that is understated and not too expensive.

“Anything to basically make what you’re wearing less recognizable and more discreet is a really good starting point,” Mr. Hajjar said.

Even Eugene Tutunikov, chief executive of the Atlanta-based luxury reseller SwissWatchExpo, has been careful about wearing his own watches, which include a rose gold Audemars Piguet Royal Oak.

“I don’t feel comfortable wearing my A.P. out to a restaurant or a bar, or anywhere besides a close friend’s house,” he said, for a private event like a dinner party.

“You never know who saw you walk in,” he noted, “or what’s going to happen when you leave the restaurant or go to the garage.”

He said he tended to wear watches like his stainless steel and white gold Rolex Sky-Dweller — admittedly still expensive, as it was frequently priced at around $30,000 at resale — but he felt it’s a bit less showy than some of his other timepieces. And for a planned trip to Italy, he is considering buying a timepiece by Tudor that is less than $5,000 and might choose a canvas strap for an even more subdued look.

Mr. Tutunikov said sales for luxury watches had continued to be brisk, but he acknowledged that many of his clients had become concerned about theft. “We are seeing a lot of people that are scared to buy watches with diamonds, watches that are made of precious metals, because they really jump out at any potential criminals,” he said.

With that in mind, during the last couple of months, he has focused on offering more watches that retail for $20,000 or less, and that are restrained rather than over-the-top.

“I don’t want to stock it if people are going to be nervous to buy it,” he said. “It’s safer to stick with less expensive inventory.”