Research into the breeding habits of the Siberian salamander conducted by the city of Kushiro indicates that the creatures laid half the amount of egg clusters this season that they produced last year, city officials said.

The salamander, often described as a living fossil from the Ice Age and designated as a semiendangered species in the Environment Ministry's "red book," focused on Hokkaido's Kushiro moor.

Although only 15 egg clusters were discovered during the study, which was conducted Thursday, a curator at the municipal museum said, "The number of egg clusters varies every year depending on water levels, and this year's figure is not particularly low."

According to the city, which conducted the research, there have been relatively low amounts of rainfall and snow this year, influencing breeding conditions for the salamanders, which lay their eggs underwater.

The Siberian salamander is amphibious and measures about 10 cm long. With an olive-colored pattern on their backs, they have four digits on each of their feet.

The egg clusters laid on underwater foliage appear fluorescent blue when exposed to light.

One egg cluster contains approximately 120 eggs.

Apart from Kushiro moor, the great northern salamanders are also found in Siberia and the islands off Hokkaido's northern coast.