Postcards with cute baby seal from Germany

I received both postcards from Germany, but from different postcrossers. I like the stamp of WWF on the first postcard very much, but I don't know, who and why put it on the postcard, as it is not WWF's postcard. On the second postcard I found sticker from 4th International Postcrossing Meet-up in Bielefeld in Germany. There was no message on this postcard, just signatures of about 45 postcrossers from around the world :) It was a big and nice surprise.