Part 2-Conserv,ation, Management, Ethics: Polyak and Provencio--- Tubes 133 Section A-Identifying and Protecting Resources I

Protecting Lava Tube Victor J. Polyak and Paula P.Provencio I

Basaltic lava flows worldwide contain beautiful and impressive lava tube caves. Although just as intriguing and delicate as limestone caves, there is a perception that lava tube caves have not been as thoroughly studied and protected as limestone and dolostone caves. This chapter offers a Outdoor recreational activities such as have become increasingly popular over the last few decades. As a result, there are equally accelerat- brief synopsis of the ing impacts to n~tural and cultural resources in caves. Prior to the Federal uniqueness of Resources Protection Act of 1988, there was undoubtedly less tube caves with incentive to man~ge and protect most caves, and lava tube caves were no emphasis on preser- exception. (See cave laws, page 217; for complete text of the Act, see vation, conserva- Appendix I, page 507.) There was also no meaSure for determining the impact to these caves, mainly because little was known about the lava tube tion, and protection. caves and their resources. Since the Act was implemented, management emphasis of publicly owned lava tube caves has shifted from recreation to conservation (Nieland 1992). There is now a need to more thoroughly define lava tube caves and their resources so the most appropriate manage- ment plans can b'e administered. What should be preserved in a lava tube cave? This is the fundamental question that ultimately leads to the protection of lava tube caves and their features. Caves of Washington by William R. Halliday (1963) and An l/Ius- trated Glossary of Lava Tube Features by Charles Larson (1993) are mono- graphs that point out what exists in these caves in terms of uniqueness and worthiness of preServation. While the lava features in lava tube caves are often small and difficult to see, they are truly unique and usually very fragile. Once damaged, these features do not recover and are not easily restored. Lava tube caves can be quite diverse and complex, as indicated in the Proceedings of the 6th International Symposium on Vulcanospeleology (Hong 1992), published by the National Speleological Society. Braids, mazes, multi-levels, vertical entrances, crawl ways, and immense are descriptors oflava tube cave passages. Mineralogical deposition in these caves can be equally impressive. This chapter offers a brief synopsis of the uniqueness oflava tube caves with emphasis on preservation, conservation, and protection. I Resources in Lava Tube Caves

Lava tube caves lre formed in flows. Unlike limestone caves, they form rapidly (over weeks, months, or years). Those interested in the origin and character of lava tubes can refer to Greeley (1987, 1971, 1972), Peterson and Sw,mson (1974), Allred and Allred (1997), Rogers and Mosch (1997), and others. The timing of the speleogenesis oflava tube caves can simply, be determined by dating the basalt bedrock of the cave. During the active lifetime of the lava tube, remelting of the surfaces produces lava features that mimic commonly found in limestone caves, such as and . These are primary 134 and Restoration

speleogenetie features (formed when the cave formed). Secondary speleothems like those found in limestone caves can also form in lava tubes. Because the speleogenetic features and secondary speleothems found in lava tube caves are generally small and often not easily seen, they are vulnerable to damage by visitation.

Lava Features Visitors often overlook lava features because of their dark color, or because the features are not defined. Common lava features in caves are lava stalactites, stalagmites, helictites, columns, flowstonc, coralloids, grooves (flow lines), shelves, ceiling cusps, linings, lava falls, dams, levees, gutters, and benches (Larson 1993). Cavers tend to be most familiar with lava features that resemble typical speleothems such as.stalactites and stalag- mites. Figure 1. This lava Although most of these -looking lava features are small and was delicate, some can be quite large and impressive. For example, a lava probably broken by column 7.6 meters (29.4 feet) high is located in a Korean lava tube cave early cave visitors (Hong 1992). Lava stalagmites can exceed 3 meters (10 feet) in height. (shown here on top of Small stalagmites and other lava features (for example, peanut-sized lava a glove). These bubbles) on cave floors are very vulnerable to damage by visitation (Figure features are not easily 3). Even shelves and benches that appear to be physically robust can be noticed with carbide or damaged easily (Figure 2). weak electric lights. Lava features should receive as much recognition and protection as

speleothems in limestone caves. Lava helictites seem to be as unique and rare as carbonate helictites. Lava stalagmites, in most cases, are extremely delicate and are much rarer than carbonate stalagmites. Continued lack of protection for these features will make them exceedingly rare.

Mineral and Depositional Resources Lava tube caves usually contain secondary salts, carbonates, and silicates. The salts usually consist of gypsum, epsomite, thernardite, and mirabilite. These form delicate speleothem types such as crust and moonmilk. Calcite is common in lava tube caves, also as coralloids, crust, and moonmilk. Silicates such as amorphous silica and poorly formed magnesium clays (trioctahedral smectite) are also found in lava tube caves in crust, coralloids, and moonmilk. Oxides are observed in lava tube caves as iron- oxides (probably hydrous) which commonly coat or stain the walls. Ice decorates many lava tube caves, creating spectacular speleothems. Found in caves located in cooler climates, some ice speleothems can be very large and long-lived if the cave temperature perennially stays below O°C (32°F). Other ice speleothems are seasonal, melting during the summer and fall, and reforming during the winter and spring. Some ice deposits have potential to reveal important historic or climatic information (Dickfoss and others 1997). Part 2-Conservation, Management, Ethics: Polyak and Provencio-Lava Tubes 135

Figure 2. It is not known whether this broken lava shelf was damaged by people ~11:." h .,. climbing on it, or whether it broke naturally. In any case, ;;:;;j;~~~.:., j. ~~ these types of features . . are prone to damage '.~r-'" by careless visitors. Dark spots or Ii~es on lava surfaces (isolated and discrete features) may be fonned by dripping water or ice melt and airflow, and appear to be spots where the original lava surface is left clean. These secondary features are not speleothems or lava features, and may seem unimportant to most visitors in lava tube caves. As insignificant as these floor spots might seem, they may provide information regarding past cave climate. Since they seem to result from dripping water, they may also be microhabitats for unusual or important life. Another interesting secondary feature found in many lava tube caves is rockflour. This po~dery material otien can he associated with primary features such as linings, and is a weathering product.

Biologic Resources Scientific research of lava tubes has accelerated over the past 40 years with NASA becoming interested in habitats for extraterrestrial life and potential human shelter. (See cited references tor microbiology, pages 78-82.) Caves 136 Cave Conservation and Restoration

have interesting biology and lava tube caves are no exception. Many traditional cave studies in biology relate to bats. Bats frequently use lava tubes, and bat habitation of lava tube caves can be significant. For instance, one of the larger bat colonies in the southwestern United States resides in an impressive lava tube cave. Since the twilight zones of these caves are commonly extensive, other animals also frequently use lava tube caves. The ecological balance of lava tube caves is olten quite fragile. For The ecological example. beautiful carpets of moss develop near entrances and below balance of lava tube skylights in the lava tube caves of EI Malpais National Monument. These caves is often quite are important habitats for invertebrates and microorganisms. Silvery or fragile. golden-colored slimes are olten observed on the walls and ceilings of lava tube caves-these reflective slimes result from colonies of bacteria such as actinomycetes (Northup and Welborn 1997). Microbes may also be partly responsible for the origin of secondary deposits such as moonmilk and vermiculations. (See biofilms page 68.)

Cultural Resources Caves made good shelters for people of early cultures. Lava tube caves were used as burial or religious sites. or as places of refuge (La Plante 1992; Sinoto 1992). Important cultural materials still exist in many lava tube caves (Cresswell 1999). Religious resources are precious to native cultures and are receiving greater respect and protection. Cultural materials in lava tube caves are difficult to protect because the materials, if still present, are typically exposed and visible on the bedrock floors. To ensure preservation of these resources, cavers should report potential cultural sites to the appropriate archaeologists and keep the cave locations confidential.

Protecting Lava Resources: Restriciting Visitation and Establishing Trails

Lava Tube Cave Entrances Establishing restrictions (permits. signage, gates. trails) in lava tube caves is not straightforward because the cntrances are usually too large to gate, and entrance areas often harbor a number of different resources. Many lava tube cave entrances form niches for plants and animals not common elsewhere in the region surrounding the caves. This is well discussed by Establishing restric- Northup and We1bourn (1997) and citations within. For instance, lava tube tions (permits, signs, caves in the southwestern United States provide havens for moss, grass, or gates, trails) in lava fern gardens, which are often located at entrances or below skylights. These tube caves is not gardens are habitats for mites, flies, microbes, and other creatures. Visitors straightforward be- need guidance to avoid trampling or disrupting these fragile ecosystems. Who knows what future studies of these sites might reveal? cause the entrances Archaeological materials are sometimes located on the surface near cave are usually too large entrances. Rock walls that were constructed as shelters arc often observed. to gate, and entrance Long tree logs are found at the mouth of collapses near entrances to lava areas often harbor a tube caves and were sometimes used during historic or prehistoric times as number of different bridges or ladders to enter the caves. Disturbing any artifacts destroys the resources. cultural history of these caves. Lava Tube Cave Passages The cave floor is the area most prone to damage from visitation, especially if visitors are unaware of fragile cave resources. Pennanent damage can occur even by lightly walking across a delicate area. For instance, some- times there are abundant spots and lines on a lava tube floor. These floor features are often hard to see and might seem insignificant. but they may harbor important climate and microbial information. Floor deposits can be Part 2-Conservation, Management, Ethics: Polyak and Provencio--Lava Tubes 137 I easily obliterated by just a few visits to a lava tube cave if trails are not established and properly used. Small lava features on cave floors, walls, or ceilings are easily damaged by unmanaged visitation (Figure 3). Large features can be tempting structures for curious and energetic visitors. For instance, some shelves are very well formed and large enough to walk or crawl on, and may be easily broken (Figure 2) if guidance and restrictions are not in place. Speleothem deposits such as moonmilk, coralloids, and crusts are also prone to inad- vertent or intentional damage by visitors. Many deposits seemingly having little scientific or historic value-but even mounds of rock flour should be protected for aestheticI reasons and for future scientific. research. Impacts from Emergency Situations Search-and-rescue groups often have no experience in caves and no special knowledge about lava tube cave resources---eonsequently, personnel may inadvertently damage a cave during a search. Much damage can be prevented if an organized caving group has inventories and maps of area caves. Familiar with caves, and equipped with the proper gear and maps, I Figure 3. This small lava stalagmite with a lava straw welded to it is in the center of a crawl passage. Increased visitation will undoubtedly damage this special little candlestick stalagmite, which is less than 10 centime- ters (4 inches) in height. Also note lava "peanuts" (bubbles) on the cave floor sur- rounding the stalag- mite. 138 Cave Conservation and Restoration

cavers can assist search-and-rescue efforts with increased efficiency, thoroughness, and minimum-impact stewardship. Until we are content with "virtual cave visits," trails will have to suffice as a means for protecting important areas of caves from frequent visitation. Many areas in lava tubes contain fragile and unique features. Probably the best way to protect these features in caves that receive frequent visitation is to establish trails. Developing trails that will not contribute to contamination is a challenge. Trail development, approached as a science, will hopefully be a significant topic of spelcology in the near future; appropriate materials for cave trail construction and placement strategies need to be addressed. (See trails, page 175.) Conservation management through restricting visitation, Conservation man- establishing trails, and posting signs to limit impact can help protect the agement through natural and cultural resources. restricting visitation, establishing trails, Potential Hazards of Lava Tube Caves and posting signs to limit impact can Skylights help protect the Skylights are intriguing openings in the ceilings of lava tube caves that natural and cultural almost always have an associated vertical component. An important resources. conservation message-Be Prepared-is especially important in avoiding the inherent hazards of lava tube caves. On the surface, sma)) skylights are not easily seen. Hiking at night, or running in areas with lava tube skylights can be dangerous. Also, the thickness of cave roofs around skylights can be very thin. Approach lava tube cave skylights with great caution, or better yet, simply avoid walking near them.

Ceiling Collapse Many lava tube caves have ceilings that are partially collapsed. While these caves seem solid and stable, blocks are obviously falling from the ceiling over time. Frost wedging is one of the culprits. Caves that fit this descrip- tion and receive moderate visitation should be monitored periodically for evidence of freshly fallen blocks. In this type of cave, avoid touching the ceiling. Managing agencies might want to carefully consider allowing open public access to caves with partially collapsed ceilings. Approach lava tube Hypothermia and Histoplasmosis cave skylights with Many lava tube caves are cold. Basalt is a good insulator and lava tube great caution, or caves often form eflective cold air sinks. Hypothermia is the chilling of the better yet, simply body's core temperature and commonly results from caving. Halliday avoid walking near (1974) and Mosberg (2006, page 271 in this volume) describe in detail them. how hypothermia can fatally atTect cavers. Prepare properly for cold cave environments and avoid hypothermia.

Dress warmly. As well, anticipate changes in surface weather. Take along a small thermos of hot fluids to drink. Carry snacks with high fat content (tor example, summer sausage and nuts). Ask for the assistance of fellow cavers if you feel chilled. Never underestimate your situation. Take precautions at the first sign of shivering. (See hypothermia, page 271.)

Other health hazards are common for cavers visiting lava tubes. Deposits of guano and rodent middens may create a cave environment conducive to diseases such as histoplasmosis. Travel carefully to avoid stirring up dust or spores, and wear respirators for protection in dry, dusty caves. (Sec histoplasmosis. page 277.) Part 2-Conservation, Management, Ethics: Polyak and Provencio-Lava Tubes 139 , Conservation Management Rapid growth orthe world population is contributing to increased human impacts on caves in at least two ways. I Encroachment by housing and business development. • Accelerated v'isitation by people.

Lava tube caves a!e no exception. Since the Federal Cave Resources Protection Act of 1988, under-funded federal agencies in the United States are increasingly r~lying on volunteers for assistance. In lava tubes, cavers are helping by suryeying the caves, inventorying the cave resources, and organizing cave cleanups. In the United States, volunteers are providing an important service, but the responsibility of saving and preserving the significant publicly owned lava tube caves ultimately belongs to the appropriate federally employed managers (Nieland 1992). (See cave management tools, page 229.) Managing human curiosity and the will to explore on one end and mali- In lava tubes, cavers cious intentions on the other is a great challenge. (See managing caves or are helping by cavers, page 237.)1Controlling urban and industrial encroachment in some surveying the caves, areas will be an even greater challenge in the quest to preserve the world's inventorying the beautiful lava tube caves. cave resources, and orgamzmg cave I Acknowledgements cleanups.

We are grateful to 1members of the Sandia who are participating in a survey and inventory project that directly supports protection of the lava tube caves in EI Ma1pais National Monument. We also thank John Lujan, Herschel Schulz, and the stafT of EI Malpais National Monument for supporting the ongoing research oflava tube caves in the Monument. This volunteer effort has enabled us to offer the information herein regarding the protection oflava tube caves. I Cited References Allred K, Allred C. 1997. Development and morphology of , Hawaii! Journal ofCa!'e and Studies 59(2):67-80. Cresswell LT. 1999. Archaeology of the Snake River Plain, Idaho. In: Kline T, editor. Idaho. the Underground Gem. The 1999 National Speleologicat'Society Convention Guidebook. Filer Idaho. p 23-25. Dickfoss PV, Betancourt JL, Thompson LG, Turner RM, Thronstrom S. 1997. History,ofice at Candelaria . In: Mabery K, editor. Natumillistory of £1 Malpais National Monument. New Mexico Bureau of Mines & Mineral Resources, Bulletin 156. p 91-112. Greeley R. 1971. Observations of actively forming lava tubes and associated structures. Modern 2(3):207-223. Greeley R. 1972. Additional observations of actively forming lava tubes and associated structures. Modern Geology 3(3): 157-160. Greeley R. 1987. The role of lava tubes in Hawaiian volcanoes. In: Decker RW, Wright TL, Stauffer PH, editors. Volcanism in Hawaii. United States Geological Survey Professional Paper 1350 (Vol 2). Reston (VA): U.S. Geological Survey. p 1589-1602. Halliday WR. 1963. Caves of Washington. State of Washington Division of Mines and Geology, Information Circular 40. Olympia (WA): State of Washington, Department of Conservation, Division of Mines and Geology. 132 'po Halliday WR. 1974. American Caves and Caving: Techniques, Pleasures, and Safeguards of Modern Cave Exploration. New York: Harper & Row. 348 p. I 140 Cave Conservation and Restoration

Hong SH. 1992. Caves in Cheju Island, Korea. In: Rea GT, editors. 6th International Symposium on Vulcanospeleology: Hilo, Hawaii, August 1991. Huntsville (AL): National Speleological Society. p 168-169. Larson Cv. 1993. An Illustrated Glossory of Lava Tube Features. Western Speleological Survey, Bulletin 87. Vancouver (WA): Carlie & Jo Larson. 56 p. La Plante M. 1992. Recently discovered Hawaiian religious and burial caves. In: Halliday WR, Rea GT, editors. 6th International Symposium on Vulcanospeleology: Hilo. Hawaii. August 1991. Huntsville (AL): National Speleological Society. p 7-9. Mosberg SR. 2006. Health and hygiene related to cave conservation. In: Hildreth-Werker V and Werker JC, editors. Cave Conservation and Restoration. Huntsville (AL): National Speleological Society. p 271- 280. [This volume.] Nieland J. 1992. Inventory, evaluation, and management of publicly owned caves in the western United States and the impact of the Federal Cave Resources Protection Act. In: Halliday WR, Rea GT, editors. 6th International Symposium on VulcanG.\peleology: Hilo, Hmvaii, August 1991. Huntsville (AL): National Speleological Society. p 273-279. Northup DE, Welbourn WC. 1997. Life in the twilight zone-Lava tube ecology. In: Mabery K, editor. Natural History of £1 Malpais National Monument. New Mexico Bureau of Mines & Mineral Resources, Bulletin 156. Socorro (NM): New Mexico Bureau of Mines & Mineral Resources. p 69-82. Peterson DW, Swanson DA. 1974. Observed formation of lava tubes. Studies in 2(6):209-222. Rogers BW, Mosch CJ. 1997. In the -Lava tube origins and morphology. In: Mabery K, editor. Nall/ral History of £1 Malpais National Monument. New Mexico Bureau of Mines and Mineral Resources, Bulletin 156. Socorro (NM): New Mexico Bureau of Mines and Mineral Resources. p 61-68. Sinoto YH. 1992. Hawaiian use of lava tube caves and shelters. In: Halliday WR, Rea GT, editors. 6th International Symposium on Vulcanospeleology: Hilo, Hawaii, A/lg/lstI991. Huntsville (AL): National Speleological Society. p 3-6.