If the player visits K.K. Slider on the Saturday before their birthday (or if their birthday is on a Saturday), K.K. Slider will play a song that can only play on that day, which can only be heard live.

The song, "K.K. Birthday", would later return to the series in Animal Crossing: New Leaf, with the same requirements to hear it. Unlike Dōbutsu no Mori e+, however, it now has an aircheck version.

Dōbutsu no Mori e+ is the only version of the original Animal Crossing to not be packaged with a promotional memory card (even the N64 Dōbutsu no Mori included a themed Controller Pak). This is because the game's extra content expands the maximum file size to 72 blocks: 57 for town data, 5 for saved letters at the post office, 5 for saved patterns at Able Sisters, 1 for NES save data, and 4 for travel data. While GameCube memory cards were officially available in larger 251-block and 1019-block sizes, all first-party cards bundled with games were manufactured exclusively in the minimum 59-block size.

If the player hits Tom Nook's store door with a shovel after it closes for the day, it will suddenly open. The player can then enter the store to find Tom Nook half awake in his PJs. He will still follow them around the store, but he will be very slow. This does not happen in the English Animal Crossing.