I have been 5 days waiting for a second festive pygmy mouse to visit mine. What am I doing wrong?

Try using Fruit or Berries and low tables. The Pygmy Mouse is the rarer of the 4 critters.

How do I activate the seasonal quests? I have only started, with my first quest.

Click on the scroll link at the top of your screen & then click on "see all quests" scroll down to find the Winter Wonderland (seasonal quest) & click activate when you are ready to start hunting....

Click on the scroll icon on the green toolbar, then click on View All Quests and select the Level 1 quests tab. Scroll down and the seasonal quests are at the bottom. Choose the one you want to do, and click the green Activate Quest button.

You activate them in the same way that you activate the other quests: click the scroll on the green bar at the top, click the View All Quests button, click your level at the top to bring up the list of quests for that level, then scroll down to the quest you want to activate and click the Activate Quest button.

The seasonal quests are at the bottom, and there is a Winter Wonderland quest in level 1 so you will be able to do that.  You could also use the seasonal mice and ducks for the level 1 Mouse Hunter and Nice Weather for Ducks quest, and the seasonal wildlife also count towards some of the other ordinary quests too - Arctic Hare counts for The Tortoise and the Hare, the seasonal birds count for Watch the Birdie, and so on.

FAR too slow this morning!!

Thank you for all the tips, Sandra, Claire and Tracey! Especially that seasonal animals count as well. Can I do part of a quest, then pauseand save, and continue with another quest? For example, it would be easy to find hares now, but tortoise difficult. Can I collect hares, and pause that quest until I am ready to search for tortoises after winter animals?

No, sadly not - you can only have one active quest at a time.  The only way to stop one quest to start another is to cancel it, and that means you lose any progress you have made.