White Sands National Park is a United States national park located in New Mexico and surrounded by White Sands Missile Range. The park covers 145,762 acres (227.8 sq mi; 589.9 km) in the Tularosa Basin, including the southern 41% of a 275-mile (710 km) field of white sand dunes made of gypsum crystals. This gypsum dunefield is the largest of its kind on Earth, with a depth of about 30 feet (9.1 m), dunes as tall as 60 feet (18 m), and about 4.5 billion short tons (4.1 billion metric tons) of gypsum sand.
About 12,000 years ago, the Tularosa Basin had large lakes, streams, grasslands, and Ice Age mammals. As the climate warmed, rain and snowmelt dissolved gypsum from nearby mountains and carried it into the basin. Further warming and drying caused the lakes to evaporate, forming selenite crystals. Strong winds then broke up these crystals and moved them eastward. A similar process continues to create gypsum sand today.
Thousands of animal species live in the park, with many being invertebrates. Several species have white or off-white coloration. At least 45 species are found only in this park, with 40 of them being moth species. The Tularosa Basin has also been home to many people, from early Paleo-Indians thousands of years ago to modern farmers, ranchers, and miners.
White Sands National Park was first named White Sands National Monument on January 18, 1933, by President Herbert Hoover. Since 1941, the park has been surrounded by White Sands Missile Range and Holloman Air Force Base. Congress redesignated it as a national park in 2019, with President Donald Trump signing the law on December 20, 2019. It is the most visited National Park Service site in New Mexico, with about 600,000 visitors each year. The park has a drive from the visitor center to the dunes, picnic areas, a backcountry campground in the dunefield, marked hiking trails, and sledding on the dunes. Ranger-guided tours and nature walks are offered at various times throughout the year.
History
The oldest known human footprints in North America were discovered at White Sands. Researchers found about 60 fossilized footprints in layers of gypsum soil on a large playa in the Tularosa Basin. These footprints are surrounded by layers of seeds from a plant called Ruppia cirrhosa. Scientists used radiocarbon dating to determine the seeds are between 21,000 and 23,000 years old. This is much earlier than the current belief that humans arrived in North America around 13,000 to 16,000 years ago. Some scientists questioned the dating because the plant seeds take carbon from water, not air, which might make the dates seem older. However, other methods, like dating pollen and quartz grains, later confirmed the older dates. Footprints from extinct animals, such as ground sloths and mammoths, were also found near the human footprints.
Paleo-Indians lived near Lake Otero, a large lake that once covered much of the Tularosa Basin. They used stones from nearby mountains to make spear points called Folsom and Plano points, which they attached to spears to hunt mammoths, camels, sloths, and bison. Tools and projectile points have been found near ancient shorelines, streams, and hills. As the large ice sheet over North America melted, Lake Otero dried up, leaving behind Alkali Flat and Lake Lucero. The area became drier over time, turning into a desert. The large animals that once lived there disappeared, leaving behind fossilized footprints.
The Archaic people improved hunting tools by using a device called an atlatl to throw spears farther. After Lake Otero dried, wind carried gypsum sand into the basin, forming large dunes. Archaic people moved into the area about 4,000 years ago, possibly drawn by a grass called Indian ricegrass. They began farming by growing wild plants more reliably. They lived in small villages year-round to care for their crops. Hearth mounds, made of fire remains like charcoal and ash, were found in the dunes. When gypsum is heated to 300°F (149°C), it turns into plaster that hardens when water is added and then dries. This process preserved the hearths for thousands of years.
The Jornada Mogollon people lived in the Tularosa Basin from about 200 CE until around 1350 CE. They made pottery, built homes, and farmed the land. They left behind clay houses and pottery pieces. Over 700 years ago, Apache groups followed bison from the Great Plains to the Tularosa Basin. They lived in temporary shelters like wickiups and teepees. Apaches defended their land against settlers and fought with soldiers, including in the Battle of Hembrillo Basin in 1880. This battle is the closest evidence of the Apache Wars (1849–1924). Eventually, Apaches were forced to leave their homeland and move to the Mescalero Apache Reservation. They still honor their connection to the land today.
Spanish settlers avoided the Tularosa Basin until the 1800s because it lacked water and was a stronghold for Apaches. When they did enter, they used trails to the salt pans near Alkali Flat. These trails, established in 1647, connected salt deposits to silver mines in Mexico. Salt was important for processing silver. Later, Texan-American settlers claimed land for mining. James Magoffin tried to collect fees for salt gathering but used force against Hispanos in 1854. Courts later ruled that salt deposits should be freely available to the public.
In 1849, U.S. Army officers explored south-central New Mexico. They mapped a possible route to the Sierra Blanca mountains. In 1861, Hispanic families started farming in Tularosa and La Luz. They mixed water with gypsum sand to make plaster for their adobe homes. The white color helped keep homes cool in the summer.
In the 1880s, heavy rains brought back grasslands, attracting ranchers from Texas. Cattle ranching became the main economy for 60 years. The Lucero brothers began ranching near Lake Lucero in 1897. By 1940, their family owned 20,000 acres. The National Park Service later took over their land. Visitors can see parts of the Lucero family’s ranch, like old stock pens and a windmill, on ranger-led tours.
At the start of the 1900s, discoveries of oil, coal, and other minerals led to mining claims in the Tularosa Basin. By 1904, over 114 people claimed more than 10,400 acres of Lake Lucero for mining. However, few of these claims were successful.
Geography
White Sands National Park is in southern New Mexico, on the north side of U.S. Route 70. It is about 15 miles (24 km) southwest of Alamogordo and 52 miles (84 km) northeast of Las Cruces. The park is in western Otero County and northeastern Doña Ana County. The closest commercial airport is in El Paso, Texas, about 85 miles (137 km) away. The park is in the Tularosa Basin, with heights ranging from 3,887 feet (1,185 m) at Lake Lucero to 4,116 feet (1,255 m) at a former military site called NE 30.
The park’s main feature is a large field of white sand dunes made of gypsum crystals. This gypsum dunefield is the largest of its kind on Earth. The park protects 115 miles (300 km) of the 275-mile (710 km) dunefield, which is about 42% of the total area. The remaining 160 miles (410 km) of the dunefield are located to the north within White Sands Missile Range. The gypsum sand is about 30 feet (9.1 m) deep below the area between the dunes, and the tallest dunes are about 60 feet (18 m) high. The dunefield contains about 4.5 billion short tons (4.1 billion metric tons) of gypsum sand, which formed around 7,000 to 10,000 years ago.
The park covers 148,588 acres (232.2 square miles; 601.3 square kilometers). In 2019, the park added 4,855 acres (7.6 square miles; 19.6 square kilometers) when its boundaries were changed to include more land. White Sands Missile Range borders the park on all sides. A special area called the cooperative use area is in the park’s western part, where public access is only allowed with a permit. This area includes most of the Alkali Flat region in the park’s northwestern part, as well as Lake Lucero and dome dunes in the southwestern part. The San Andres Mountains are beyond the park’s western edge, and Holloman Air Force Base is nearby to the east. A rock formation called Twin Buttes is located to the south on land managed by the Bureau of Land Management.
Climate
White Sands National Park has a climate classified as continental or cold semi-arid (BSk) by the Köppen system, which is very similar to a cold desert climate (BWk). Average daily temperatures are similar to those of a humid subtropical climate (Cfa), but the park’s high elevation and low rainfall cause greater daily temperature changes and a shorter growing season. On average, the growing season lasts less than six months, from April 27 to October 19.
The warmest months are April through October. During these months, the average high temperature is 79 °F (26 °C) or higher, and daily average temperatures range from 60–81 °F (16–27 °C). Afternoon temperatures in June and July average about 97 °F (36 °C). The highest temperature ever recorded was 111 °F (44 °C) on June 22, 1981.
The cooler months are November through March. During these months, the average low temperature is below 32 °F (0 °C), and daily average temperatures range from 39–52 °F (4–11 °C). December and January are the coldest months. The lowest temperature ever recorded was −25 °F (−32 °C) on January 11, 1962.
The park receives an average of 9.81 inches (249 mm) of rain each year. August is the wettest month, with about 1.88 inches (48 mm) of rain. July through October have the most rainy days, averaging four to seven days of precipitation each month. Other months have about two to three days of rain. Snow can occur from November through March, with an average snowfall of 1.6 inches (41 mm).
Geology
During the Permian Period, shallow seas covered the area that now forms White Sands National Park. These seas left behind gypsum, a type of calcium sulfate. Later, tectonic activity raised parts of the gypsum-rich seabed, forming parts of the San Andres and Sacramento Mountains. Over time, rain dissolved the water-soluble gypsum in the mountains, and rivers carried it to the Tularosa Basin, which has no connection to the ocean. The trapped water either seeped into the ground or formed shallow pools that dried up, leaving gypsum on the surface in a crystalline form called selenite. Groundwater that flows out of the Tularosa Basin moves south into the Hueco Basin. During the last ice age, a large body of water called Lake Otero covered much of the basin. When Lake Otero dried up, a flat area of selenite crystals remained, known as the Alkali Flat.
Lake Lucero is a dry lakebed in the southwest corner of the park, located at one of the lowest points in the basin. Rain, snowmelt from nearby mountains, and water from deep underground sometimes fill Lake Lucero with water that contains dissolved gypsum. When full, the lake covers about 10 square miles (26 square kilometers) and is 2–3 feet (0.61–0.91 meters) deep. As the water evaporates, small selenite crystals about 1 inch (2.5 centimeters) in size form on the lake’s surface. Most of these crystals develop during large floods that happen every 10 to 14 years. Wind and water gradually break the crystals into smaller particles until they become fine grains of white gypsum sand.
The ground in the Alkali Flat and along Lake Lucero’s shore is also covered with selenite crystals that can be up to 3 feet (0.9 meters) long. Over time, weathering and erosion break these crystals into sand-sized grains. Prevailing winds from the southwest carry these grains away, forming white dunes. The dunes constantly change shape and slowly move downwind. Since gypsum dissolves in water, the sand that makes up the dunes may dissolve and harden after rain, creating a more solid layer. This increases the dunes’ resistance to wind but does not stop them from quickly covering nearby plants. Some plants grow fast enough to avoid being buried, while others use strategies like forming hardened structures around their roots to stay stable.
White Sands has many types of dunes. Dome dunes are found along the southwest edges of the dune field, while transverse and barchan dunes are in the center. Parabolic dunes appear along the northern, southern, and northeastern edges. Scientists have studied the dunes by using lasers to measure them, installing shallow water wells across the dune field, analyzing the chemistry and age of water below the dunes, measuring sand grains from across the dunes, and using satellites to track temperature and moisture changes throughout the year.
On the western side of the dune field, dunes are more than 50 feet (15 meters) tall and become smaller toward the eastern edge, where they stop abruptly. Water is only a few feet (a meter) below the surface across the dunes, but it is very salty. On the western edge, the water is older and even saltier. The depth to groundwater decreases from 5 feet (1.5 meters) below the surface on the eastern end to 1–2 feet (0.3–0.6 meters) on the western end. Dunes on the western side have little vegetation and move quickly, while dunes on the eastern side move slowly and have more vegetation. Sand grains on the western edge are larger and have varied shapes, while those on the eastern edge are small and round. The dune field is cooler and wetter than the surrounding desert, based on satellite images. Scientists have found evidence of old lakeshores beneath the dunes using laser scanning technology. At these old lakeshore areas, dune movement and types change significantly.
Ecology
White Sands National Park is home to more than 600 invertebrates, 300 plants, 250 birds, 50 mammals, 30 reptiles, seven amphibians, and one fish species. Many animals in the park have white or light-colored fur, scales, or skin, including three mammals, three reptiles, one amphibian, and many insects. At least 45 species are found only in this park, with 40 being moths. Other unique species include the Apache pocket mouse, White Sands woodrat, bleached earless lizard, and two types of camel crickets.
The plants in the park help hold the edges of the dunes together, providing food and shelter for animals. People have used these plants for food, clothing, and medicine for many years. Native Americans made mats from thick grass blades and ate some grass seeds.
The plants in the park must be very tough to survive in the poor, salty soil. Many plants can live in temperatures that go as low as below freezing and as high as over 100°F. They also survive in soil with high salt levels, and some plants, like gypsophiles, grow best in these conditions.
Cane cholla cacti, soaptree yucca, and other desert plants store water during hot summers and dry winters, blooming in spring. Desert grasses grow in the salty soil, and their seeds provide food for animals like Apache pocket mice and kangaroo rats. Grass seeds are rich in protein and are stored by rodents in underground caches.
Native Americans used parts of the soaptree yucca for food, clothing, and soap. They ate young flower stalks, boiled or roasted flower pods, and used leaf fibers to make rope, mats, sandals, and cloth. The roots were boiled to make soap.
Other plants include skunkbush sumac, Rio Grande cottonwood, hoary rosemary mint, purple sand verbena, Mormon tea, and claret cup cactus. American Indians used skunkbush sumac berries to make a tart drink and used its stems for baskets. Purple sand verbena was used as a mild sedative. Cottonwood bark was used to treat injuries, and a tea made from it helps reduce inflammation. Mormon tea contains ephedrine, which helps with cold symptoms.
More than 800 animal species live in the park, many of which are active at night. Some animals have adapted to survive in the dry environment with little surface water and salty groundwater. Some species have evolved to have lighter colors than their relatives elsewhere, helping them blend into the white sand and avoid predators. Examples include the Apache pocket mouse, bleached earless lizard, sand-treader camel cricket, sand wolf spider, and certain moths.
Invertebrates are the largest group, with over 600 species, including spiders, wasps, beetles, and moths. Spider species include the Apache jumping spider, burrowing wolf spider, funnel-web spider, tarantula, and western black widow. Other arachnids are the sand scorpion and wind scorpion. Insects include the white-lined sphinx moth, yucca moth, bleached skimmer dragonfly, tarantula hawk wasp, and Maricopa harvester ant. The Maricopa harvester ant has the most toxic venom of any insect, causing severe pain in humans and killing small animals.
As of November 2019, 246 bird species have been recorded in the park, including wrens, mockingbirds, ravens, roadrunners, and raptors. Some birds are seen daily, while others are spotted only rarely. Common birds include mourning doves, turkey vultures, hawks, and sparrows. Cactus wrens build nests in cacti and hunt insects near shrubs or on car radiators. Birds are often seen near the visitor center, the edges of the dunes, and Lake Lucero, which is open to the public once a month.
Most mammals in the Tularosa Basin stay in their dens during the day to avoid the heat. Visitors may see animal footprints on the dunes from nighttime activities. Carnivores include coyotes, bobcats, badgers, and kit foxes. Rabbits include desert cottontails and black-tailed jackrabbits, which can run up to 40 mph. Rodents include porcupines, pocket gophers, Apache pocket mice, and Merriam's kangaroo rats, which can jump up to 10 feet high when startled. The pallid bat hunts insects on the ground and is often seen near the visitor center.
Common lizards include the bleached earless lizard, little white whiptail, southwestern fence lizard, and side-blotched lizard. Common snakes are coachwhips, Sonoran gopher snakes, prairie rattlesnakes, western diamondback rattlesnakes, and massasaugas, all of which are venomous. The only turtle in the park is the desert box turtle.
Seven amphibian species live in the park, including three types of toads and three types of spadefoot toads.
Paleontology
Before the Pleistocene epoch ended about 12,000 years ago, the Tularosa Basin had large lakes, streams, and grasslands. The climate was wetter and cooler, with more rain and snow than today. Lake Otero was one of the largest lakes in the southwest, covering 1,600 square miles (4,144 km²), an area larger than the state of Rhode Island.
The basin had many animals, including large Ice Age mammals that lived near Lake Otero and in the surrounding grasslands. Columbian mammoths, ground sloths, ancient camels, dire wolves, lions, and saber-toothed cats—also called saber-toothed tigers, though not closely related to tigers—walked across the Tularosa Basin, where the dunes are now. The animals left fossil footprints as they walked on the muddy shores of Lake Otero. Their weight pressed into the wet clay and gypsum. These fragile tracks are uncovered by wind but quickly erode, with many disappearing after just two years.
Scattered across the now-dry lakebed are trackways of ancient camels and Columbian mammoths. The fossilized footprints often gather near old water pools. For 80 years, only a few fossil footprints were found in the park. However, scientists noticed dark spots on the lakebed that looked like footprints. In the 2010s, footprints of a dire wolf were found next to ancient seeds dating to more than 18,000 years ago. Fossil footprints of ground sloths have also been discovered in the park. Sometimes, paleo-human footprints are found near Ice Age animals. One set of footprints shows humans walking near sloths. The people who lived in the Tularosa Basin left no other evidence of their presence. Though stone flakes from tools, arrowheads, and spear points are found nearby, these belong to people who lived after the Ice Age. The lakebed has very few artifacts from before the Spanish arrived in the 1500s. In a study of Lake Otero in 2021, Bennett and others found human footprints dating to about 23,000 to 21,000 years ago, showing that humans lived there before the Clovis people.
Dire wolves lived in North and South America during the Pleistocene. They were about 2.6–2.8 feet (80–85 cm) tall and weighed 130–150 pounds (60–68 kg), similar in size to modern gray wolves but with a stronger, more muscular build. They had powerful jaws with a stronger bite than modern wolves and likely hunted in packs to target large prey like horses and bison.
During the Pleistocene, large cats lived worldwide, including lions in North America. American lions were about four feet (1.2 m) tall at the shoulder and weighed over 500 pounds (230 kg). They had long legs for chasing prey and hunted by ambushing animals like deer, camels, ground sloths, bison, and young mammoths.
Saber-toothed cats are known for their large canine teeth, which could be seven to ten inches (17–20 cm) long. They stood about 3 feet (1 m) tall and weighed up to 750 pounds (340 kg). Their strong, muscular build helped them catch large prey like sloths, bison, and young mammoths. Some fossil evidence suggests they may have hunted in packs.
Columbian mammoths stood up to 14 feet (over 4 m) tall at the shoulder and weighed 18,000–22,000 pounds (8,000–10,000 kg). They had large tusks and ridged teeth for eating plants, similar to modern elephants. Unlike woolly mammoths, they probably had little hair. They lived from Canada to Nicaragua and Honduras.
Camels are often linked to Africa, but they originated in North America. Ancient western camels may have looked like modern dromedary camels but had longer legs, standing up to seven feet (over 2 m) tall at the shoulder. They were opportunistic herbivores that grazed over large areas and left distinctive footprints.
Ground sloths are related to modern tree sloths, armadillos, and anteaters. Harlan’s ground sloth stood 10 feet (3 m) tall when upright and weighed over a ton (2,200–2,400 pounds or 1,000–1,090 kg). These slow-moving herbivores left kidney-bean-shaped footprints, created as their back feet rotated inward while walking. Some tracks look bipedal, possibly because their large hind feet covered the smaller front footprints. These tracks have sometimes been mistaken for human footprints.
Visitation
White Sands National Park is the most visited National Park Service site in New Mexico, with around 600,000 visitors each year. During the second year of the pandemic, the park welcomed more than 780,000 visitors, including both local and out-of-town guests. Many visitors come during the warmer months, from March through August, but sledders and photographers can be seen in the dunes all year. March and July are the busiest months, with more than 60,000 visitors each, or about 2,000 per day. November through February have the fewest visitors, with less than 30,000 each month, or fewer than 1,000 per day.
The Dunes Drive is an 8-mile (13 km) road that leads into the dunes from the visitor center at the park entrance. Three picnic areas are available, as well as a backcountry campground with ten sites for overnight camping in the dune area. Five marked trails that are 9 miles long (14 km) let visitors walk through the dunes. Ranger-led orientation walks and nature tours happen at different times and months throughout the year. Sunset strolls are offered every evening, while Lake Lucero hikes are available once a month from November to April. Full moon hikes are held from April to October on the night before the full moon. The park has a Junior Ranger Program with activities for different age groups.
Both the park and U.S. Route 70 between Las Cruces and Alamogordo may be closed for safety reasons during missile tests at White Sands Missile Range, which surrounds the park. Dunes Drive may be closed for up to three hours during these tests. Park staff is usually notified two weeks ahead of scheduled tests, but sometimes only 24 hours’ notice is given. All activities, including horseback riding, backcountry camping, hiking, sledding, and driving on Dunes Drive, are not allowed during missile tests that require road closures. According to a National Park Service report, in 2020, visitors spent about $22.5 million in nearby communities. In 2021, there were over 360,000 more guests, which helped boost local towns.