Black oil sunflower Seed is probably the most familiar and most popular type of birdseed, for good reason. With this one type of birdseed in your feeders, you can attract dozens of bird species to your yard. When compared to striped sunflower seeds, black oil seeds are meatier and have a higher oil content which gives your birds more nutrition and calories in every bite. Black oil seeds also have thinner shells than striped seed, making them easier for smaller birds to crack. Starlings may have a harder time cracking them open, so may deter them (yay!) but more and more are figuring it out. This is probably the most economical way to feed the birds at your feeder.
Update June 18 2020 – Seed prices are going up. Sadly and frustratingly, times being what they are, between the major uptick in demand for birdseed in general during Covid 19, lack of supply, big conglomerate hoarding, and in some cases borders closing to business, prices are going up effective of this date.