鶴だより 2019年12月

English translation by Michael Eabry

Fumio Matsumoto

December

As we move into December, feeding has begun and the Red-crowned cranes are starting to gather in the Red-crowned Crane Village. However, there are still only about 20 to 30 birds in the feeding grounds. The first snow has already fallen this year, but there haven’t been any significant snowfalls and bare earth is visible in the fields. Prior to coming to Akan village and gathering at the feeding area, these cranes seem to have been foraging for food in the surrounding fields.

On December 5, a survey of the distribution of wintering Red-crowned cranes was conducted by the Hokkaido government. There were about 30 birds at the feeding ground in Akan, but further north, three flocks of about 30 to 50 birds were spotted and it is thought that there are maybe 150 to 160 Red-crowned cranes in the vicinity of Akan village.

As a result of the Ministry of the Environment’s feed reduction project, started in 2015, the amount of feeding may have been reduced but the environment in the surrounding fields seems to have changed significantly. Akan is not only a vegetable farming region, but also home to a thriving dairy farming industry. Many of the fields under dairy farm management are pastures for feeding cows. However, cows are fed not only on grassland fodder but also on formulaic feedstock, high in nutritional value, of which one is dent corn (maize used for feed). This dent corn was previously imported in large quantities, but in recent years the number of farms where it is grown on-site has increased. Dent corn fields are harvested by machine, but after harvesting there is plenty of food, such as scattered corn, left in the fields for cranes to feed on.  This growth in dent corn fields is increasing the feeding grounds available for cranes.

The increase in dent corn fields is occurring not only in Akan but also in various parts of eastern Hokkaido. For this reason, even at this time, flocks of Red-crowned cranes exist in Nemuro and the northern part of Kushiro. Eventually, if fields become snow-covered and food is no longer accessible, it is thought that the cranes will move to the feeding areas, but changes in agricultural patterns are also influencing the behavior of Japanese cranes in autumn.