I have always kept at least one or two feeders in the yard,strictly filled with Black Oil Sunflowers,and most days,that's where you would find that "Crowd of Birds".These seeds are highly favored by the majority of birds who visit my yard.Let's not forget the squirrels,as they will park themselves right at the feeder and eat them until they're ready to burst.
They are high in protein and are a great help to the bird's essential health throughout those cold winters when food is on the scarce side.
My yard attracted many,many birds,and it did get to eb a very costly but but satisfying venture.

Pros: just about all will birds enjoy them

Cons: can get quite costly if you feed a lot of birds

We only feed in the winter time. We find that the bears are attracted to sunflower seeds in the summer, and we cannot have the bear around!!! But in the winter, we feed only black oil sunflowers with cracked corn (mostly for the doves that visit our feeders). We have noticed that when we purchase any other type of sunflower seeds, there is more empty shells and waste in what you are purchasing - and the birds tend to "pick" through the seeds to find what they want. This is a great year to feed birds - we've had species that I have never seen at a feeder before - I think because of the conditions - which seem to be extreme due to icing. Harder for the birds to forage for seeds and grasses.

Pros: Less Waste

Cons: More Expensive

I have always kept two feeders filled with the black oil sunflower seed - one for the birds, and one for the squirrels. The red squirrels like to knock the top off of the feeder & sit in it while he eats - the gray squirrels feed below as he spills. It gets expensive, but I like to watch them as well as the birds.

Black oil is a must - tried other sunflower seeds and they are not as popular with a wide array of birds.

Pros: Most Popular bird food

Cons: none

There's no substitute for black oil sunflower seeds. They're good for birds, plus birds of all kinds at my feeders have always selected these seeds over all other kinds I've put out. When black oil sunflower seeds fall onto the ground, birds and squirrels eat them, so no waste. If nobody eats the ones on the ground, the seeds sometimes surprise me with small sunflower plants that bloom---lagniappe!

Pros: no waste

Cons: easily fall out of feeder openings

We keep the bird feeder filled year-round & it's been bitter cold & icy & the birds learn where the feeders are, so it's important to keep them filled especially when they can't find food elsewhere.
Best Choice has good black sunflower seeds, the birds enjoy them a lot. This is a brand I buy often & it's less expensive than some without compromising quality.

Pros: birds love it!

Cons: none