Sadness and neglect
The days gradually lengthen and the nights slowly become shorter.The opposite happens after the Summer Solstice.
they need more feed and should have a shelter at least one side and a roof out side is there norm free of mold and dust they will be healthy dont foreget water!!
the earth spins around and the sun stays in place so when you are on the opposite side of the earth that the sun is facing its dark.