Environment Planet Earth Explore Dinosaur Fossils, Wildflowers, and Dark Skies at Big Bend National Park By Katherine Gallagher Katherine Gallagher Writer Chapman University Katherine Gallagher is a writer and sustainability expert. She holds a B.A. in English Literature from Chapman University and a Sustainable Tourism certificate from the GSTC. Learn about our editorial process Updated October 29, 2022 Fact checked by Elizabeth MacLennan Fact checked by Elizabeth MacLennan University of Tennessee Elizabeth MacLennan is a fact checker and expert on climate change. Learn about our fact checking process Share Twitter Pinterest Email Photography by Deb Snelson / Getty Images Planet Earth Outdoors Weather Conservation Known as one of the most remote parks in the lower 48 states, Big Bend National Park is bordered by the famed Rio Grande River—which also serves as an international border between the United States and Mexico. In fact, Big Bend National Park gets its name from the large bend in the river that curves along the boundary of the park, covering a distance of 118 miles. President Franklin D. Roosevelt signed the bill to establish Big Bend as a national park in 1935, helping protect a southwestern Texas landscape rich in fossils and desert as well as the plants and animals that continue to thrive there today. So much more than the meeting point of different cultures and landscapes, Big Bend National Park also preserves the history of its earliest inhabitants. Learn more about this unique destination with these 10 curious facts. Big Bend National Park Is Larger Than Rhode Island At 801,163 acres in size, Big Bend National Park may not be as large as other continental United States properties like Death Valley National Park (over 3 million acres) and Yellowstone National Park (over 2 million acres), but it’s still pretty impressive. The landscape there is composed of vegetation belts along the Rio Grande, sections of the Chihuahuan Desert, Chiso Mountains, and limestone Boquillas Canyon. The Park Has the Darkest Measured Skies in the Lower 48 States Rebecca L. Latson / Getty Images The International Dark Sky Association added Big Bend National Park to the list of Gold Tier International Dark Sky Parks in 2012, the largest up until that time. Research conducted by the National Park Service Night Sky Team found that the exceptionally dark night skies at Big Bend were free from all but minor impacts of light pollution, so much so that they offered the darkest measured skies in the lower 48 states. Big Bend National Park Has Lost Seven Native Fish Species So Far Factors such as increased pollution, water flow loss, and invasive species have continued to negatively affect the Rio Grande’s aquatic systems. Since the park's inception, seven native fish species have been lost completely, leaving two of the remaining species listed as federally endangered and a species of concern. There Are at Least 1,200 Species of Plants Inside the Park Donovan Reese / Getty Images Thanks to a large range of elevations, the biological diversity inside Big Bend National Park is quite abundant despite its dry climate. About 1,200 plant species are supported by this diversity, including various types of orchids that bloom in the canyon shade, hardy plants that have adapted to the desert, and weeping willow trees along the Rio Grande. Depending on the time of year, visitors may experience bursts of bluebonnets (the Texas state flower), cactus blooms, or even a rare superbloom after particularly rainy winters. The park offers several hiking trails that help showcase some of its most stunning wildflower displays and forest groves. What Is a Superbloom? A superbloom is a desert phenomenon that happens when, after unusually heavy winter rains, dormant wildflower seeds sprout all at the same time, creating a thick proliferation of flowery vegetation. Big Bend Is Home to Over 450 Bird Species Although more than 450 species of birds have been reported in Big Bend National Park, only 56 species live there year round. Because of this, the type of birds one may see inside the park greatly depends on the time of year, and continuing to monitor migration patterns of specific birds is important to the overall diversity of the environment. One such species, the colima warbler, has become somewhat of a legend among Big Bend bird watchers (the park is the only place on Earth where the birds are known to live). Every five years since 1967, dozens of citizen scientists journey throughout the boundaries of Big Bend in order to count colima warblers in the name of research. There Are 150 Miles of Hiking Trails Inside the Park Opportunities for hikes and backpacking trips inside Big Bend National Park stretch over 150 miles with elevations ranging from 1,800 feet along the river to 7,832 feet on Emory Peak. The higher elevations found in the Chiso Mountains boast over 20 miles of peak trails, while the drier landscapes in the Chihuahuan Desert region offer plenty of space for quiet, peaceful hiking. In order to protect the solitude and serenity of Big Bend’s environment, the park requires groups larger than 30 to split up and hike separate trails. Big Bend Protects 22 Species of Bats Fred Bruemmer / Getty Images From the cave myotis and the tri-colored bat to Townsend’s big-eared bat and the Mexican free-tailed bat, there have been 22 bat species documented inside of Big Bend National Park. These bat species are under threat from Pseudogymnoascus destructans, a fungus that causes white-nose syndrome, leaving park officials concerned that it could make its way into Big Bend next. The disease was first detected in Texas in 2017, after spreading extensively throughout the United States and killing an estimated 6.7 million bats between the years of 2006 and 2011 alone. The Park’s Geological Structures Date Back Millions of Years Photography by Deb Snelson / Getty Images While the visible surface area of Big Bend is considerably young when compared to Earth as a whole, most of the exposed rock found throughout the park still ranges from 100 million to 500 million years old. According to the National Parks Service, geologists often refer to Big Bend’s landscape as “jumbled” or “chaotic” due to its rocks being exposed at odd angles and standing vertical or even completely upside down. Those Rocks Help Preserve Abundant Fossil Records Big Bend National Park is of particular value to scientists since it preserves a largely intact slice of geologic time that spans about 130 million years—the longest and most diverse of any United States national park. The fossil record helps researchers discover more about the park’s geologic history and study evolution and extinction events throughout time, especially that of the late Cretaceous and early Tertiary periods. Over 90 Dinosaur Species Have Been Discovered at Big Bend National Park In addition to the numerous fossilized plants, fish, crocodiles, and other early mammals that have been found in Big Bend National Park, scientists have also discovered over 90 species of dinosaurs (some of which were previously unknown to science). Nearly 70 of these species were discovered in the Aguja Formation, a former swampy environment that formed between 80 and 75 million years ago. View Article Sources "The Rio Grande." 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