The recent outbreak of a highly virulent strain of bird flu has taken a toll on bird exhibits and events at zoos nationwide ahead of the Chinese zodiac Year of the Rooster in 2017.

According to a survey by Kyodo News, 64 zoos that belong to the Japanese Association of Zoos and Aquariums, or about 72 percent of the total, have taken measures to prevent the spread of bird flu, such as canceling bird exhibits or events related to the Year of the Rooster.

The most common measure was to cancel events in which visitors can touch and feed birds, given the bird flu virus could be brought in on visitors' shoes.

A zoo in Chiba Prefecture decided to stop offering a service in which visitors can take pictures with chickens for New Year's greeting cards.

Nogeyama Zoo in Yokohama suspended events in which visitors can touch chickens and take pictures.

Higashiyama Zoo and Botanical Gardens in Nagoya has temporarily closed its zoo area after detecting the highly pathogenic virus in black swans that died between late November and early December.

Despite the precautions, zoo operators remain concerned that they won't be able to protect their birds from infection.

"We're taking measures so that wild birds (that could be carrying the virus) stay away, such as by placing nets above bird areas and putting them indoors at night, but it is difficult to reduce the risk to zero," said an official at Izu Shaboten Zoo in Ito, Shizuoka Prefecture.

The Environment Ministry said that as of Friday it had logged 69 cases of avian flu infection affecting birds in the wild and zoos in 13 prefectures, topping the record 62 cases marked in the 2010-2011 season.