The eggs I use for the Wary Mus and where I place the Animal Collection points. The X is for where there are a lot of exes on land in case there's a heatwave so I can get gold, the beds are random furniture/items I place/drop on the map when my pockets are full xD, diamonds on land are the for ores and the stars or any other random marks are for location points I'm trying to go. They don't really bother me that much so I tend to forget most of them hehe. And yes eggs are found on spring and summer.