Research on newly exposed ground
Cooper, a University of Minnesota botanist, visited Glacier Bay in 1916. Retreating glaciers exposed land of different ages, providing opportunities to compare colonization, soil development and vegetation change.
He established permanent plots in the West Arm. These allowed comparisons among surfaces as well as later observations of actual change in the same places.
Extending observations through time
Cooper repeatedly returned to chart plant growth and species composition. His student Donald Lawrence continued the work from the 1940s until the late 1980s.
After the plot locations were lost, a 2016 team used hand-drawn maps, corrections for magnetic declination, notes, historical photographs and metal detectors to relocate them and record individual plants again.
References: [2]
What the centennial return found
The 2016 survey found that early-colonizing willows persisted in some plots, while alder and spruce had not replaced them according to a simple sequence of stages.
The researchers proposed dispersal distances and resource occupation by early arrivals as possible explanations. Revisiting the plots tested particular processes rather than merely confirming an assumed succession timetable.
References: [2]
Preserving a scientific opportunity
After another visit in 1921, Cooper argued more strongly for preserving Glacier Bay’s research opportunities. Through the Ecological Society of America he organized colleagues to advocate federal protection.
Glacier Bay National Monument was established in 1925 with scientific study among its purposes. The value of permanent plots also depended on retaining the land beyond an individual researcher’s career.