TOKYO — Tourists are known for acting silly, but licking the tuna?

Overwhelmed by a growing number of misbehaving tourists, Tokyo fishmongers banned all visitors from one of the city's most popular tourist destinations — the pre-dawn tuna auctions at the world's largest seafood market.

The ban, imposed during the peak New Year buying season, was front-page news before it was lifted last week. Now, the tourists are back, but the debate goes on: Can tourists be trusted around the tuna?

"We understand that the sight of hundreds of frozen tuna looks unique and interesting for foreign tourists," said Yoshiaki Takagi, deputy director of the market. "But they have to understand the Tsukiji market is a professional place, not an amusement park."

One of the more notorious recent cases was that of a tipsy British tourist — caught on tape by a Japanese TV crew — who licked the head of a frozen tuna and patted its gill. Two others, also caught on video, rode around on a cart used by wholesalers. "Get out! Get out!" an irate market official shouted in English.

"Tuna is a very expensive fish," Takagi said. "One tuna can easily cost more than 1 million yen ($11,000). But some tourists touch them and even try to hug them."

Fed up, the market decided to impose the ban.

So, when on Jan. 5, a premium bluefin tuna fetched 9.63 million yen — more than $107,000, the highest price in nearly a decade — no tourists were anywhere in sight. The restriction was lifted on Jan. 19, despite some grumbling from the fishmongers.

The sprawling market dates back to the 16th century, when the military rulers who had just moved Japan's capital to Tokyo — then called Edo — wanted to ensure they had a steady supply of fish.

Today, Japan is the world's biggest consumer of seafood. The market handles 480 kinds of seafood, attracting around 40,000 buyers and sellers daily. The value of its seafood trade amounts to $20 million per day on average, making it the heart of the national seafood distribution system and the biggest fish wholesale market in the world.

It's the kind of place the Japanese take for granted. But it has become a big hit with foreigners because of the colorful way the fish are auctioned off by men in rubber boots and baseball hats using arcane hand signals and the sheer volume and variety of fish available every day.

Nearly 90 percent of visitors for tuna auctions are non-Japanese, Takagi said — a figure that seemed pretty much in line with the crowd at Tsukiji one recent morning.

The no-nonsense fishmongers at Tsukiji do not see themselves as an attraction, but rather as workers with pressing business. The most common complaint from auctioneers is tourists using flash cameras, which makes it difficult for them to read the finger signals used for bidding. The market put up English signs saying "No Flash!" but that was widely ignored, Takagi said.

After the ban was lifted, the market began distributing leaflets at the entrance of the tuna auction site in English, Chinese, Korean and Russian, as well as Japanese. Along with the no-flash warning, it tells visitors to stay within the observation area and leave promptly after the auctions, which open at 5 a.m.