Research inCarlsbad Caverns National ParkScientific exploration and discovery
ABOUT THE COVER
Mexican free-tailed bats have roosted on theceiling in Carlsbad Cavern for over 5,000years. Within the past 50 years their numbershave declined from several million to about500,000.
Research inCarlsbad Caverns National Park
Carlsbad Caverns National Park providesunparalleled opportunities to see south-western wildlife, desert plants, majesticlimestone mountains, and hidden caves.The park is many things to people whocome here to experience its wonders. It isespecially important to scientists as aplace to investigate cave geology, as wellas desert plants and wildlife. It is aunique, protected natural area, shapedlargely by natural processes.
The following science articles provide aglimpse of the research being done inCarlsbad Caverns National Park. Thisresearch is often a cooperative effortbetween federal and state agencies, withvaluable contributions from universityscientists, students, and other partners.The park resource management staffinventories and monitors importantresources such as bats, mountain lions,migratory birds, and endangered cactus.Other scientists are conducting in-depthinquiries into cave geology, water quality,paleontology, microbiology, mammalogy,and fire ecology. These articles will sharea brief but important picture of scientificdiscoveries that have emerged throughthe efforts of dedicated researchers overthe past five years.
The park is entrusted to conserve caveresources, thus preserving a precious partof our national heritage. For more than75 years, the National Park Service hashad a dual responsibility to conserve theresources of the national parks andprovide for their enjoyment by theAmerican people. Increasing numbers ofvisitors and a myriad of influences fromthe modern world are turning this dualmission into a battle. Today some of thedistinguishing features and resources ofCarlsbad Caverns National Park are injeopardy. These threats require monitor-ing of ecological conditions and applica-tion of science-based management toprevent further resource degradation.Existing data and new information iscontinuously integrated into resourcestewardship efforts.
Carlsbad Caverns, Underground World
The caves of Carlsbad Caverns NationalPark contain sites with exceptionalnatural beauty. The parks most famouscave, Carlsbad Cavern, is over 1,000 feetdeep and currently contains 30 miles ofmapped passages. The Big Room ofCarlsbad Cavern is the largest under-ground chamber in the United States.Massive stalagmites, stalactites, columns,flowstone, travertine, and cave popcorndecorate the room. The parks largestwildlife attraction is a colony of Mexicanfree-tailed bats, numbering in the hun-dreds of thousands, that live in the cave.The colony spends six months eachsummer in the cave where their youngare born.
2 Research in Carlsbad Caverns National Park
The park protects Lechuguilla Cave, thedeepest limestone cave in the UnitedStates. Here the superlative geologicalformations have astounded speleologistsfrom around the world. The worldslargest collection of bacterially-assistedbiothems exist in the cave. Recentresearch has revealed unusual microbesin poolssuspected lithotrophic bacteriathat derive metabolic energy from sulfur,manganese, and iron. More than 1,200strains of microbes from pools, soils,corrosive residues, and sulfur depositshave been isolated.
In all, the park has 85 caves with a totalof over 136 miles of known passages androoms. These caves contain some geo-logically unique and rare cave forma-tions. This area contains one of thebest-preserved, exposed Permian Agefossil reefs in the world. The park cavesprovide a unique opportunity to view afossil reef from the inside.
The Guadalupe Mountains of southeast-ern New Mexico preserve an excellentfossil record of Permian Age (250 millionyears ago) marine life. The GuadalupeMountains are the uplifted remains of anancient reef which developed around theperimeter of a shallow sea. Unlikecontemporary coral reefs, this reef wascomprised of the skeletons of calcareoussponges and algae. At the time of thereefs development, corals were not anabundant species. By studying the fossilrecord, we can learn more about ancientmarine ecosystems.
Dr. Kevin Rigby of Brigham YoungUniversity described several fossilsidentified for the first time within Per-mian rocks in North America at CarlsbadCaverns National Park. The largest fossilsponge known from the Permian Age wasdiscovered near the entrance of CarlsbadCavern.
By examining the structure of fossils, Dr.Fagerstrom of the University of Coloradoreports that Sphinctozoa sponges devel-oped from a seafloor-dwelling species toa reef-builder through the thickening ofthe sponges walls and internal structures.This increased structural mass allowedthe sponges to withstand the forces ofwave action and create a base skeletonaround which the reef developed. Siltsand broken skeletal pieces becametrapped within the structure and ce-mented into place by algal mats.
Carlsbad Cavern offers both researchersand the public an interesting view of theinterior of an ancient reef. From thisperspective, we gain insight into theprocesses which created the backbone ofthe Guadalupe Mountains. Throughcontinued research we gain a betterunderstanding of the Capitan Reef andthe Permian Age.
Living Reef to Limestone Rock
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Lechuguilla Cave was known for years asMisery Hole, a 400-foot long cave whichwas mined for guano in the early part ofthis century. For years, those enteringnoted a wind which issued from a rubblepile within the cave, yet it was not untilMay of 1986 that an entrance was dugthrough the rubble to an unexplored cavebeyond. Since the breakthrough, Lechu-guilla Cave has yielded over 89 miles ofpassages and numerous mineralogical,geological, and microbiological discover-ies. The cave is 68 degrees Fahrenheitwith 99% humidity.
For thousands of years, the only influ-ences from the surface came from waterseeping through the rock (no flowingstreams) and the air which the caveinhaled or exhaled according to changesin barometric pressure outside. In thisrelative isolation, a separate and uniqueecosystem developed which supported itsown brand of life. This cave first ap-peared to be uninhabited, but life existsinvisible to the naked eye. Dr. LarryMallory, a former University of Massa-chusetts professor, has started studies ofmedicinal uses of newly discoveredmicrobes in Lechuguilla.
The unique conditions found in Lechu-guilla Cave have given rise to adaptationof certain microbes to allow them tosurvive in this caves environment.Without sunlight or a consistent organicfood source, life in this cave has beenlimited to microbes capable of reducingminerals for energy and to microbes whoeat these primary producers. Most of thelife is contained within the caves pools,concentrated at the bathtub ring aroundthe pools where the air, water, and rockinterface. The limited availability of foodhas dictated severe competition, and eachpool within the cave has developed itsown distinct population of microbes,
most of which have never before beenidentified.
With his interest in medicinal uses formicrobes, Dr. Mallory hypothesized thatthe scarcity of food likely caused thesemicrobes to develop means for eliminat-ing their competition. This survival tacticcould be in the form of a compoundwhich one microbe may produce to killoff other nearby microbes. So far, afterfour years of sampling, over 1,000microbial strains have been discovered inLechuguillas pools. This research hasprovided the park with a new understand-ing of the caves fragile ecosystem, aseach pool appears to be different fromany other.
In order to evaluate the changes inLechuguilla due to human explorations,Ms. Diana Northup, a researcher with theUniversity of New Mexico, has initiateda study to determine the extent of humanimpact. Exploration and research inLechuguilla Cave often requires multi-day trips. Certain microbes would bepresent in this cave environment onlythrough human introduction. By testingareas that havent been visited for sometime, we can learn whether or not thecave recovers from such disturbances.Although bacteria contaminations werefound within the cave, populations dodecline with time.
Life, as we are learning, can be found inthe most unexpected of places, and wemust be careful in our activities to avoidaltering a balance achieved only by time.The challenge now is to incorporate whatis currently known about LechuguillaCave into a management plan thatprotects this valuable resource.
Microbes Below the Surface
Cave Bacteria and Life on MarsThe Viking space craft 20 years ago failed to find conclusive evidence of life on the surfaceof Mars. Despite this evidence, some researchers believe that microbial life may now existunderground on Mars, sheltered from the hostile surface environment.
We know that microbial communities on Earth have adapted to an amazing array of hostileconditions. Bacterial life can be found in boiling hot springs, or in the flares of active volca-noes, and even deep underground.
Dr. Chris McKay and other NASA scientists have come to Lechuguilla Cave in CarlsbadCaverns National Park to study microbes that survive in a sulfurous environment similar towhat may be found on Mars. What makes this study so intriguing is that some bacteria heremay derive energy from sulfur. The group of scientists continues to study the bacterial andfungal ecosystem of the cave and speculate whether similar life forms survive on Mars.
6 Research in Carlsbad Caverns National Park
At Carlsbad Caverns there is a large,active colony of roosting bats with along-