How much do the dunes change over time?
While the immediate surface of the dunes changes constantly, the main dunefield as a whole is fairly stable. Comparing recent photographs with photographs taken in the late 1800’s reveals that the major dunes have maintained their overall shape and position. Vegetation in the surrounding area prevents significant migration of new sand into the main dunefield. When flowing, Medano Creek catches sand blowing from the main dune mass east towards the Sangre de Cristo Mountains and carries it back to the southern edge of the dunes to the point where the creek disappears. When dry, the sand can then blow back onto the dunes in a unique recycling pattern that has played an important role in building these dunes. When the creek is dry, sand can blow across the creek bed forming escape dunes which suffocate ponderosa pine stands as they march eastward towards the mountains.
