Tokyo-based Chinese restaurant Totenko Co.’s stock climbed as much as 10% after the city’s Ueno Zoo announced that its giant panda Shin Shin delivered twins this morning. Another nearby restaurant chain Seiyoken KK saw its shares advance as much as 7.4%, with trading volume on both at least 10 times the three-month, full-day average.

“Currently, the staff is working together to observe and protect the panda mother and cubs,” Ueno Zoo said in a statement.

Both stocks have been seen as a gauge for panda-related news, climbing earlier this month when the zoo announced that Shin Shin may be pregnant after mating with male panda Ri Ri.

Visits to the Ueno Zoo currently require a reservation, with visitors limited to 2,000 a day under coronavirus infection prevention measures. The pandas are among the zoo’s main draws, with Shin Shin and Ri Ri’s daughter Xiang Xiang—who turned four this month—among the first attractions seen as visitors enter.