Detection thresholds, auditory filter widths, and temporal modulation transfer functions were measured in European starlings before, during, and after a 10-day injection series of kanamycin, an ototoxic aminoglycoside antibiotic. Hearing loss in response to the drug exposure was observed in frequencies at or above 3 kHz; threshold shifts above 3 kHz were >60 dB. The auditory filter broadened at 5 kHz from 9% to 20% of center frequency (CF). After 60 days of recovery, detection thresholds improved to within 15 dB of predose estimates, and auditory filters at 5 kHz recovered to 11% of CF and were permanently changed in the skew toward lower frequencies. At 3 and 1 kHz, changes in filter bandwidths were small and transient. At 3 kHz, no permanent change in filter width occurred, but filters were permanently skewed toward lower frequencies. At 1 kHz, changes in skew occurred, but only during the period of greatest threshold shift at higher frequencies. Temporal resolution was largely unaffected by hearing loss, although some loss in sensitivity to amplitude modulation was observed during the period of profound hearing loss. The data are discussed in terms of the relation among auditory functions and the perception of birdsong by starlings after hair cell regeneration.