Here are a few more words I picked up from our travels in Hokkaido last month and from my followup reading in Ann Irish's book Hokkaido (McFarland, 2009).
道産子 Dosanko '(Hokkai)do-born-child' – Originally applied to a particular breed of horse, the Hokkaido Pony (北海道和種 Hokkaidō washu), this term now applies to anyone or anything from Hokkaido: from prefecture-marketing antenna shops to cooking styles to streetcar types. It has become the prefecture's brand name.
毬藻 marimo 'ball seaweed' (Aegagropila linnaei) – We first saw marimo on display in a small aquarium by the souvenir shops in JR Kushiro train station. They are a species of filamentous green algae (Chlorophyta) that forms large and velvety green balls. Colonies of such balls are only known to form in lakes in Iceland, Scotland, Estonia, and in Japan, where they are one of the many attractions of Lake Akan in Kushiro. The Japanese botanist Kawakami Tatsuhiko (川上龍彦) gave it the name marimo in 1898. Ainu names for it include torasampe ('lake goblin') and tokarip ('lake roller'). English names for it include Cladophora balls, Lake balls, or Moss balls. Marimo also gave rise to a whole range of mascot merchandise under the name Marimokkori.
ペチカ pechika 'Russian stove' – It was in Hokkaido that I learned that Japanese ikura 'salmon roe' was borrowed from Russian икра (ikra), and in Irish's book I learned of another Japanese borrowing from Russian, pechika 'Russian stove' from печка (pechka), the diminutive of (Русская) печь '(Russian) oven/stove'. The Japanese who settled Hokkaido adapted some Russian techniques to deal with the harsh northern winters, including horse-drawn sleighs with curved runners and stoves that radiated heat more effectively than the open fireplaces that were standard in traditional Japanese living/dining rooms. Those settlers included not just migrants from Honshu during Meiji times, but also refugees from Sakhalin, the Kuriles, and Manchuria after World War II ended. My impression is that Japanese pechika refers not to the large Russian ovens of clay, brick, or tile, but to smaller iron stoves, like the one in this Japanese fisherman's workroom. Irish (p. 285) mentions "the Japanese song Pechika, which describes a family telling stories around a stove."