Over the years I have experimented with different seed and suet for the songbirds that I attract to my yard.  Because I build birdhouses, and have quite a few in my yard (understatement) I wanted food that would attract the birds I was looking for but not the rodents that I am not fond of!
After having a pest company over once, which is enough for anyone, I learned an interesting fact.  The rodent called rat has a favorite food.  It is called "blackened sunflower seed".  Most of my seed had plenty of that and I needed to rid my feeders of those for obvious reasons!  So I tried all different things until I bought "hot pepper suet cakes".  My feeding stations are now clear of all the rodent activity and I have a diverse bird population in my yard including the Northern flicker, Downy Woodpeckers, Chickadees, Yellow Warbler, Nuthatch, Sparrow, Jays, Juncos, etc..  It is high in fat which helps our warm blooded birds stay warm,  a wide variety of birds are eating as well if not better than when I used seed. AND THOSE THINGS WITH LONG tails are gone!!

Keep in mind when you feed to keep the feeder atleast 10 feet away from any birdhouse that is being used.  Parents do not want to defend their territory to feeding birds.  They become stressed and can harm their health and their babies!

One other tip, after all the ground feeders like the Junco, Golden Crown Sparrow, Towhees are done for the day, it doesn't hurt to sweep up remainders!