The Pleistocene Mojave: Fort Irwin's Prehistoric Oasis

When you look out at the Mojave Desert today, you see a landscape of sunbaked sand, rugged mountain ranges, and sparse creosote bushes.  But, 20,000 years ago the Mojave Desert was a very different place. In fact, it wasn’t a desert at all.

During the last Ice Age, known as the Pleistocene Epoch, the climate at what is now Fort Irwin was completely different.

Instead of the arid scrublands we see today, the land was marked by thriving wetlands, marshy meadows and flowing streams. Freshwater lakes such as Lake Manix and China Lake supported lush vegetation that attracted abundant wildlife.

The lower valleys were covered in a dense sagebrush, dotted with thick stands of mesquite. As you moved up the slopes of the surrounding mountains, the terrain gave way to rich woodlands. Conifers, including pinyon pines and junipers, dominated higher elevations. Down by the water's edge, reeds, marsh grasses, and aquatic plants grew thick, providing a lush grazing ground for the giants of the Ice Age.

Columbian mammoths shared these grazing lands with herds of ancient horses, giant ground sloths and the extinct western camel.

The lakes of the Mojave attracted thousands of migratory and aquatic birds. Flamingos, pelicans, swans, storks and eagles thrived in the wetland oasis.

The abundant wildlife also attracted the apex predators of the era. Sabretooth cats, packs of dire wolves, the American lion and the flat nosed bear, all roamed the Fort Irwin area looking for their next meal.

Around 15000 years ago, the climate began to change. Temperatures rose, the ice retreated and the Mojave began to give way to the relentless glare of the sun.

The lakes dried up, mammoths, sabretooth cats and dire wolves died out. The pinyon and juniper forests retreated to the highest peaks, leaving behind the desert scrub that we see today.