Stewart H. Hulse, a retired Johns Hopkins psychology department chairman who studied how birds use their song and found they possess absolute pitch, died of pneumonia Aug. 31 at Union Memorial Hospital. The former Lutherville resident was 77.
Dr. Hulse was an experimental psychologist trained in the field of animal learning. Over the course of his career, he became a founder of studies in a field known as animal cognition.
"When he started in the field, it was assumed that animals had simple brains," said his son, Stephen Vail Hulse of Baltimore. "Through his work, he found that animals had a greater richness of abilities than had been previously thought."
Born in Elizabeth, N.J., and raised in nearby Westfield, he was a 1953 Williams College graduate. He received his doctorate in psychology from Brown University.
In 1957, he joined the Hopkins faculty and spent his professional working life at the school, eventually serving as psychology department chairman. He was named professor emeritus in 1999 and most recently lived in Lakewood Ranch, Fla.
Family members said that early in his career he was an animal behaviorist who worked with laboratory rats and found they learned landmarks to negotiate a maze.
After developing an allergy to the rodents in the 1980s, he switched to common starlings captured at the Patuxent Wildlife Research Center. A 1989 Sun article called them "pampered house guests in a psychology lab, one to a cage, with curious humans watching and listening and tinkering with nearby computers."
An amateur pianist and trombone player, Dr. Hulse had studied musical theory and played in a college band. He began his studies of bird song by wondering how much the birds inherently knew about what they were singing. He questioned whether they recognized relations in sound patterns.
He found his starlings recognized a pattern of four ascending or descending tones by pecking at a choice of buttons in their cages, with a food reward for correct answers.
"And they indeed revealed a flair for the task - and Dr. Hulse and his graduate students shifted the patterns an octave in key, whereupon the birds totally lost their discrimination process," The Sun's 1989 article said.
A 1997 story in a Hopkins publication said that Dr. Hulse "discovered that European starlings were able to accurately pick out specific bird songs when mixed with other songs and even when accompanied by 'the dawn chorus' - the combination of sounds heard in the forest during a spring morning when all the birds are singing at once."
