Scientific interest in Glacier Bay remained high in the years following Muir and Harriman. One of the scientists was also a visionary. William S. Cooper, a plant ecologist studying the return of plant life to the recently de-glaciated terrain, made numerous trips to Glacier Bay beginning in 1916. Enthralled with the beauty of the area, he convinced the Ecological Society of America to spearhead a campaign for its preservation. These efforts met with success in 1925, when President Calvin Coolidge signed the proclamation creating Glacier Bay National Monument, an area less than half the size of the present park. The proclamation cited the features and values of the area: tidewater glaciers in a magnificent setting, developing forests, scientific opportunities, historic interest and accessibility.