Well, most of the wildlife are affected. But mostly the mushrooms, elks, mosses, lichen, bears and berries. The cesium replaces a mineral in animals/plants. Kalium - in swedish, i don't know the english word for it.

So when the plants use the cesium instead of kalium and the animals eat the plants... The Sami population in the north keep reindeers semi-wild, thease animals eat a lot of mosses and lichen so they often contain a lot of cesium. They have to give the reindeers grains a couple of months before they can kill the animal(to eat of course).
The fish in forest lakes could be bad too if the water stands very still.
And those who use wood to heat their houses has gotten a description how to treat the ashes(from the affected areas), which might contain cesium to avoid unneccecary exposure.
The reason why we got a lot of cesium, plotonium e.t.c. is because when the big "radioactive cloud" came by sweden it started to rain

So a lot of the atoms came down with the water and sinked into the ground.
The gouvernment says now that the most of the cesium is bound into the ground now. And the doses are small enough not to cause cancer. But everyone should avoid to eat a lot of food from the forest in the areas where it came down with the rain.
In another 10 years it will be half the amount of cesium that came down left...
I hope I didn't write too much text, It sounds horrible when I write it but you really get used to it. That you have to avoid certain things. Heh
(I pick my blueberries further inland)
//Saiva