Rather than look at “birds” as one group, let’s divide them into two main groups, according to their tastes in food: the two (basic) groups are “seed eaters” and the “insect eaters”. We’re going to use a very simple indicator to literally point us in the direction of which group birds reside in, and that’s the shape and size of their beaks.
The seed eating birds have stubby, parrot-like, beaks – broad at the base and engineered to crack the husk of seeds to extract the kernel inside (for example House Sparrows, Chaffinches, Bullfinches). These birds are happiest when they’re fed seed mixes.
Insect eaters – as you’ve probably already guessed (or already know!) have fine slender beaks (Dunnocks, warblers & tits) and the same goes for the species that prefer to feed on worms and grubs (Blackbirds, thrushes and Robins). These birds will consume small seeds but are often happier when softfoods and mealworms are provided for them.
Bill Oddie once explained to me that birds adapt to the food that’s available throughout the year but that they nevertheless still have their preferences: “Blue and Great Tits ‘prefer’ live food, but have to ‘manage’ on nuts, berries and seeds in winter. Thrushes and Blackbirds arguably have it slightly better, since their beloved worms are available all year round (except when the ground is hard from drought, or freeze up), and in autumn and winter they also gorge themselves on ripe berries.”
Two main groups, two main preferences, two main beak shapes.
So how does that knowledge affect the food you put out?
Certainly a good quality seed mixture and softfood would help divide and conquer appetites. But I think the main message to get over is that birds like a variety of food and that a variety of food attracts a variety of birds.
The same can be said when it comes to the question of how best to feed a bird diet. “Birds” once again have their preferences (ground, bird table or bird feeder). Choosing one of these places will tend to only attract certain species, whereas dividing food up and feeding it on all three levels, will attract the maximum number of species that visit your garden.