A bird feeder comprising a seed container, a center tube formed within the seed container, a seed tray, an independently calibrated cartridge spring assembly having a center rod, a spring extending about the center rod with the center rod extending downwardly of said center tube, a cover, and a hanger engaged with an upper portion of the center tube to thereby retain the cover in position, a shroud having a perch member and a central opening therein to permit the lower end of the center rod to pass therethrough, and a retainer secured to the lower end of the spring assembly.