Well, what's left is enjoying nature, sitting on the deck, walking by the river or pond, and staring at the sunset or the birds in the trees. In the winter there are no squirrels scurrying about in the grass, and birds are not nesting in the trees. There is little bicycling either, nor canoeing, nor kayaking, nor in-line skating, or running. The winter worshipers will be quick to point out that there is ice fishing and cross country skiing and ice skating during their season. But even these sports, fun as they are, find their adherents happy to get inside to relinquish the activity to warm drinks and cozy fireside chats.
Yes. Spring is wonderful not only because of the weather, but because of the blossoming of nature and the general spring fever that overtakes the land. People are happy to be out and about, and so are other animals. Everyone frolics. The seasons ahead bode more of the same enjoyment, as spring gives way to the fullness of summer, and summer recedes to the beauty of autumn.
So, what's to do during spring? Enjoy life through outdoor activity...or inactivity. Just be and bask in its beauty.