sign in sign up
<<
Home , Ascension Island, Halocline, Stalagmite, Surinam (English colony)

Submarine and Biology of text and ph(Jt(J9raphs blJ Th(Jmas M. Ifi((e Department of , Texas A & M University at Galveston, Galveston, TX 77553-1675 My scientific interest in caves began quite by accident. After finishing my PhD in June 1977, my first job was as a research scientist N at the Bermuda Biological Station, where I conducted studies of tar being washed up ( on the island's beaches. Up to that time, my A interest in caves was from a purely recreational viewpoint. I had done some cave Castle Harbour diving while obtaining my Masters degree in at State and later when teaching at the Florida Institute of Technology, When I moved to Texas to work Harrington on my PhD, I found diving opportunities to Sound be quite limited and so I contacted Houston Green Bay Cave cavers who invited me along on their trips to caves in central Texas and northern Mexico. Upon arriving in Bermuda to start my new job, I was excited to learn about the numerous and well-decorated I U·"_ caves the island had to offer. Since Bermuda 'rI is a rather small, narrow island, most of its ~_..-rl approximately 150 known caves are within a few hundred meters of the coast (Figure 1) and many contain sea level pools in their interior. Such pools. both at entrances and in the interior of otherwise dry caves, lack Fig. 1: Map ofBermuda showing the location ofprinciple caves: Green Bay, Admiral's, above ground connection with the sea and Walsingham, Palm, Government Quarry, and Tucker's Town Caves. contain tidally fluctuating brackish or salt . They are properly referred to as prior, a biologist had attempted to collect copepods, ostracods, isopods, amphipods, "anchialine." Bermuda's anchialine cave from several cave pools but found nothing mysids, and cumaceans, as well as pools contain exceptionally clear, dark blue, of interest and concluded that the caves were tanaidaceans, echinoderms, tunicates and and often quite deep . Although large lifeless habitats. Indeed at that time, Virtually fish. While many of these animals, such as submerged and stalagmites can be all investigations of aquatic cave life were sponges, echinoderms, tunicates and fish, are seen from the surface, there are typically no conducted on freshwater habitats and some normal inhabitants of the near-shore zane, obvious signs of cave-adapted aquatic of the world's most prominent cave biologists others are known only from the caves and animals from above. had stated that, with few exceptions, marine are restricted to this habitat. It was soon Curious about the apparent lack of life in caves were not important to the field of apparent that most cave-adapted (i.e., eye­ the cave pools, I asked Dr. Wolfgang Sterrer, . and pigment-reduced) animals inhabited the the director of the Biological Station, if Not to be deterred, I contacted Dr. Boris deep, marine waters in the interior of caves anyone had ever looked for animals in the Sket of the University of Ljubljana in and were thus only accessible by cave divers. saltwater caves. He told me that several years Slovenia, who was studying caves along the Therefore, specialized training in cave Adriatic coast, and diving would be required to investigate and invited him to come to catalog the fauna of Bermuda's caves. In Bermuda. Dr. Sket September 1979, I invited Paul Meng, a accepted and spent two Florida-based instructor with the weeks working with me NSS Cave Diving Section, and his friend in September 1978. We Barry Warner to come to Bermuda and teach made dives in several of a course for several friends, Paul Hobbs, Rob the more open cave Power, and me. Once properly trained and pools and found that equipped, we organized ourselves as the increased with Bermuda Cave Diving Association and depth so that at 10 to 20 began to systematically explore, map, and foot depths, the salinity scientifically document the island's anchialine approached that of the caves. open sea. It was in these Bermuda is a volcanic seamount located deeper, fully marine 1000 km off the east coast of the United waters that we States in that part of the Western Atlantic discovered a wealth of known as the Sargasso Sea. The island was marine life including created by a series of mid- volcanic sponges, gastropods, eruptions that began about 60 million years various worms, and ago, at a time when the was crustaceans, including much narrower. Subsequent

NSS NEWS, August 2003 217 Passage opens into a large silt floored chamber-the Desert-before passing under a low arch into the Trunk Passage. This is the largest passage in the cave, averaging 15 m wide and 10 m high. The far end of the Trunk passage terminates in a breakdown stope to the surface and a murky inland -Cliff Pool -the second and only other entrance to the Green Bay System. On the east side of the Trunk Passage, the Harrington Sound Passages comprise two interconnecting passageways with much clearer water than adjacent sections of the cave. The Bath Tub Ring Room at 15 m depth near the end of the Harrington Sound Passage contains a horizontal bleached band of bedrock about 50 em in width cutting across the strata (Figure 2). In the same area are bones of a sea turtle that apparently became lost and died in the cave at some time in the distant past. The North Shore Passage is the longest single passage in the cave. It begins on the west side of the Trunk Passage and extends for nearly 500 m to a point past the northern shoreline of the island, where the passage becomes too low for divers to follow. Several extended interconnecting loops characterize this part of the cave. Undercut walls and the level nature of this part of the cave at 18 m depth indicate an underground stream must 'J,!-., " have flowed through these tunnels during ~ -L~,~' ','1\ ~ , glacial low stands of sea level. Massive Marine biologist Tom IIiffe with plankton net bY'S!alagmltl! stalactites and stalagmites, present in virtually Blue Cave. Submerged speleotlilflns originally 7/ftmed all parts of the underwater cave, are another ng tbe Ages when sea level wastpwer and the c,ves indication of the cave's long history as a dry e dry. . I J! cave. -----~ Biological zonation is evident as and sea floor spreading have maintained stalactites and stalagmites, confirming that progresses farther into the cave from the Bermuda's location relative to North the caves must have been dry and air-filled Green Bay entrance. Brightly colored America, while ever increasing its distance for much of their history. sponges, hydroids, tunicates, and other from Europe and Africa as the Atlantic Ocean Green Bay Cave is presently the longest encrusting organisms literally cover the walls enlarged. Thus, Bermuda has never been cave in Bermuda, with more than 2 km of and ceiling in areas close to the entrance. As part of, or closer to, a continental landmass. surveyed passage. The main entrance is a a consequence of decreasing tidal currents As the top of the volcanic seamount was wide, submerged passageway extending and particulate matter suspended in the - eroded down below sea level, corals began inland from the end of Green Bay on water, the of these organisms declines to grow around the margins, thus producing Harrington Sound. From shallow depths at with distance into the cave. In the much the only atoll in the North Atlantic. Coral ­ the Green Bay entrance, the cave slopes clearer waters of the deep cave interior, derived limestone, first deposited as coastal progressively deeper to the Trap, a low troglobitic species predominate. dunes, caps most of present-day but wide section at 17 m depth. At this point, Other larg~ anchialine caves are located Bermuda. Approximately one million years a low side passage turns south to the on the opposite side of Harrington Sound ago, limestone caves began forming during Connection Passage and the major part of from Green Bay Cave. Two major cave glacial periods, when sea level was 100 rn or the cave, while the Rat Trap continues and systems in this area, called the Walsingham more tower. Later, as glaciers on the opens out into the Green Bay Passage. This Tract, are the Walsingham and Palm Cave continents melted and post-glacial sea levels passage climbs over breakdown at the Systems. The Walsingham System is about rose, encroaching drowned large Letterbox and passes through a tight 1.3 km long and comprises seven separate portions of the caves. Continuing collapse of restriction between collapse blocks only to entrances: Deep Blue, Vine, Old Horse, overlying rock into the large, solutionally­ enlarge again. This further extension of the Walsingham, Fern Sink, Crystal and formed voids created the irregular chambers Green Bay Passage bends back toward Wonderland Caves. Of these, Walsingham and fissure entrances that are commonly seen Harrington Sound and extends to a small air was a former commercial cave, while in Bermuda's caves. Extensive networks of bell in ceiling breakdown. An underwater adjacent Crystal and Wonderland (now submerged passageways, developed breakdown slope on the left side of the air renamed Fantasy) are major tourist primarily at depths between 17 and 20 m bell descends to a spacious, deeper chamber attractions in Bermuda. below present sea level, interconnect with a massive boulder choke at one end and Deep Blue Cave consists of an isolated otherwise isolated cave pools. These a room with distinctly lower visibility-the pool in the Bermuda jungle at the base of a passages, only accessible to divers, are well Fog Room at the other. 10 m high limestone cliff face. The pool is decorated at all depths with impressive From the Rat Trap, the Connection particularly impressive due to its crystal clear

218 NSS NEWS, August 2003 RMUOA

5 ~... 01

PLAN VIEW and cross sections

Large Cemented Breakdown Blocks ""'~~. ADMIRAL'S 1\ CHAMBER Small High Lead Entrance steep Slope ?­ \~ I. ( Dig Site nearba:~ 17 of dirt slope & / historic stalagmite - IT stump 1 ;\ r ~~~~~~~ BASEMENTEDAYLIGHT 'IA'!,t~B>;'i;li~ More Cave ~>" Lower Level ?-... _<:::;:::;=J "9 W 0 , H~ndline ENTRANCE y1 Drop ~ SINK -<:> -~'-~J

,. -'

LEGEND COMPASS and TAPE SURVEY BY: ,...... Entrance dripline :::::::: Passage walls _NORTH=-C <£8) Breakdown blocks --- Underlying passage walls Robin Barber, Rebecca Belcher, Darcy Gibbons, ~)) Flowslone ~ Slope (splays downward) Tom lliffe, Bob Richards, Sandy Stephens and (.. Wall of Trail or pathway SCALE Bernie Szuka/ski. rsN) Columns Drop or ledge (lower on right) r 5 10 20 30 SURVEYED DATES: January 7-8, 2002 ."'~ Ceiling drop (higher on right) o Stalagmites /' j •• I' '" Stalactites It Passage too tight for entry meters CARTOGRAPHY BY: Bob Richards :.'Ni;" Dirt, Silt or Soil 28 Depth below entrance c.::;::) Water ? Lead TOTAL SURVEYED TRAVERSE: 745 meters TOTAL VERTICAL EXTENT: 28 meters PROFILE VIEW

Om

10m

20m

30 m I' Emerald Poo/2 Pool @2003, BeCK1S Project commercially shown System is characterized by strong tidal section of Crystal Cave currents and a profusion of colorful sponges while another passage and hydroids, encrusting the walls. Even the extends to the second guideline through this section of the cave has pool of Wonderland become totally overgrown. Visibility is less Cave. than in other parts of the cave farther Striking contrasts removed from tidal flow. Bedrock and distinguish the Deep , where visible, are darkly Blue-Walsingham and stained as in the passageways connecting Fern Sink-Crystal­ Deep Blue and Walsingham. Wonderland segments of Government Quarry Cave was discovered the System. In the during quarrying operations in 1969 but was former, noticeable tidal destroyed when quarrying resumed in the currents are present, mid 19805. The cave contained two pools, especially in the one of which was initially explored to a restriction at Deep Blue complex fissure system reaching depths of Fig. 4: Heavily vandalized speleothems in a newly discovered and the pool at 24 m-one of the deepest underwater caves cave in Bermuda. W a lsi n g ham in Bermuda. However, before exploration Additionally, the walls could continue in the cave, large amounts water of an incredible azure color. The rocky and speleothems in this section are stained of refuse and other debris were intentionally bottom is covered by the green algae dark brown to black. In the latter parts of the bulldozed into the pool to fill it before the Caulerpa contrasted with patches of brilliant cave, no currents are evident, the visibility is quarrying away of the overlying rock. As a foliose red algae and pale brown plates of essentially unlimited, and rock surfaces show result of this dumping, water in the the reef-building coral Agaricia. Underwater, no evidence of staining or submergence. Government Quarry Cave and many the cave becomes even more spectacular as Even the frailest soda straws and adjacent caves turned anoxic and sulfurous a diver descends and enters a vast remain in pristine condition. Apparently tidal (Iliffe et aI., 1984). submerged chamber. Looking over his exchange through the system between Geological drilling operations at shoulder, the diver beholds a breathtaking Harrington Sound and Castle Harbour is Government Quarry encountered a large panorama of the broad fissure he has just directed by way of a route along the cave at 18 m depth below sea ievel. The drill entered through, silhouetted by sparkling southeast edge of the cave, while other bit subsequently dropped to 33 m where sunbeams piercing the blue water against a sections are in a hydrologically more isolated volcanic bedrock was recovered. This would backdrop of lush green algae. This cul-de-sac. imply that caves in the Government Quarry magnificent chamber continues to a rift Palm Cave System, with its five entrances area are the deepest in Bermuda and have extending to the surface and emerging in the (Cripplegate, Myrtle Bank, Palm, Sailor's been developed at the island's limestone­ more sheltered and secluded glamour of the Choice and Straw Market Caves) is located interface, averaging about 30 m below Vine Cave Pool. Dazzling red crustose immediately southwest of the Walsingham present sea level. coralline algae covers the rocks on the bottom System. Tidal flow from Castle Harbour first Tucker's Town Cave contains an immense of this overhung and dimly illuminated pool. moves through the Walsingham System and underwater chamber that is lacking in the At the northern end of the Deep Blue pool, under an impenetrable saddle valley of speleothems so characteristic of other a tight squeeze between breakdown blocks collapse origin before entering the Palm Bermuda caves. No passages have been in shallow water connects to a narrow rift System and connecting to Harrington Sound. found extending away from the chamber. that was passable only after being dug out Cripplegate Cave is a tidal on Accumulation of dune-like sand deposits by divers. From that point, a cathedral-like Harrington Sound with a shallow underwater cover the cave floor in several locations. A underwater chamber (Figure 3) ascends to a entrance opening up into a room beneath funnel-shaped depression in the floor at 18 tiny air bell, before dropping to a low tunnel the entrance pool of Myrtle Bank Cave. From m depth was apparently caused by sand at 22 m depth-the deepest point in the cave. Myrtle Bank, the cave passage splits, with dropping into a lower level. Although the The passage then climbs to the top of a rift both offshoots descending to the main level ceiling shows evidence of a collapse origin. and separates into a loop that rejoins in a of passage development at 18 m depth. The the only visible breakdown is present at the high-ceiling, circular air room. A short swim south passage consists of a high but narrow far end of the chamber from the entrance at 6 m depth then brings the diver out into fissure that appears to have originated as a pool. Water in the cave is exceptionally clear the main entrance pool ofWalsingham Cave. vadose canyon. One branch of this fissure with no sign of tidal currents. The connection to Fern Sink and the pinches out in an area very close to Numerous other anchialine caves have remainder of the Walsingham System is Harrington Sound as evidenced by the been explored by divers, but many more through a low fissure at 20 m depth off the presence of mussel shells on the cave floor. loop past the circular air bell. On the far side Another side offshoot that takes of the fissure, which is negotiable only with continues for several hundred meters before side-mounted tanks, the cave divides. One becoming too low. passage ascends a steep breakdown slope The north passage from Myrtle Bank to the Fern Sink rift pool, while another extends inland and enlarges to a tidal channel passes under a low deep arch to reach a about 5 m in diameter. It then enters a sizable major tunnel connecting two spacious air bell submerged chamber situated between the chambers, accessible only by diving. This Palm and Sailor's Choice entrances. area is magnificently decorated with Climbing over a mound of breakdown speleothems ranging from massive columns beneath the Sailor's Choice entrance, the to fragile soda straws and helictites. From the passage changes form to a high, wide rift largest of the two air bells, a narrow low connecting to the Straw Market pool. Fig. 5: Flowstone shattered by blasting passage connects to the main pool in the The Harrington Sound side of the Palm in a cave in a limestone quarry.

220 NSS NEWS, August 2003 likely await discovery. Two years ago, blasting of the caves where no in a limestone quarry uncovered a large and water currents are remarkably beautiful cave containing a deep discernible and suspended . I was called in by the Bermuda particulate matter is absent Government to document and evaluate this from the water column. cave. When I arrived on the island, I found that vandals had entered the cave and ANCHIALINE CAVE intentionally smashed speleothems ranging FAUNA from highly colored stalactites and stalagmites An extraordinarily rich to pure crystalline soda straws and helictites and diverse stygobitic (Figure 4). The effect of nearby blasting was fauna inhabits the clearly evident where actively depositing anchialine caves of flowstone slabs a meter of more in thickness Bermuda. Seventy-five had been sheared apart across the grain stygobitic species have (Figure 5). Diving exploration of the lake been identified so far from revealed the presence of an underwater room Bermudian caves, adorned with 1-2 m long straws and fantastic including 64 crustaceans, 5 Fig. 6: Typhlatya i1iffei, an atyid shrimp that with cave helictites up to 30 em in length. mites, 2 ciliates, 2 adapted sister species inhabits freshwater and marine gastropod molluscs, and 2 caves in the Mediterranean, Atlantic, Caribbean and eastern Pacific. ANCHIALINE CAVE ECOLOGY segmented worms. In order Pools in Bermuda caves typically consist of abundance, the crustaceans include 18 discovery in Bermuda, several taxa had been of a 1 to 3 m thick surface layer of brackish species of copepods, 18 ostracods, 7 known only from the Old World. Two water overlying nearly fully marine seawater. amphipods, 6 shrimps, 6 cumaceans and 3 colorless, eyeless amphipods from the genus Surface are lowest in those caves isopods. Notable in their absence are Pseudoniphargus, P. grandimanus and P. with connections most remote from the sea remipedes and thermosbaenaceans. carpa/is, are the first representatives to be and may even approach becoming totally Despite the isolated mid-ocean location found on the western side of the Atlantic. fresh. The highly stratified cave water column of Bermuda, many of its endemic anchialine Other species from this genus inhabit caves results from the absence of wind- and wave­ taxa show highly perplexing biogeographical and groundwater around the Mediterranean induced mixing. affinities. These general associations can be basin and northwest Africa, in the Atlantic Water show similar summarized into the following groups: drainage systems of Portugal and Spain and variations with depth. Surface temperatures 1. Affinities with Caribbean and West in the Azores and . A new vary seasonally depending on the position Atlantic taxa: Not surprisingly, considering genus and species of calanoid copepod, of the pool in relation to the cave entrance. Bermuda's location on the edge of the Gulf Paracyclopia_naessi, has been collected from For example, surface water temperatures in Stream, many of the island's troglobitic taxa six caves in Bermuda. It belongs to the family the entrance pool of Walsingham Cave varied show affinities to Caribbean species. The Pseudocyclopiidae represented previously by from 16 to 28°C over the course of a year, amphipod Bogidiella (Antillogidiella) only a single genus inhabiting waters around while surface temperatures in the deep bermudensis, isopods Arubo/ana aruboides the British Isles and Norway. interior pool of Crystal Cave ranged from and Curassanthura bermudensis, and shrimp The misophrioid copepod Spe/eophria 18.4 to 22.6°. Deeper waters in the more Janicea antiguensis are allied with species biuexiIJa has a sister species inhabiting isolated caves remain stable year round at from the Antillean region of the Caribbean. anchialine caves from the Balearic Islands in 19 to 200C. Affinities with Bahamian taxa include the the Mediterranean. Dissolved levels also vary with shrimp Barbouria cubensis, Typh/atya iliffei 3. Affinities with transoceanic island taxa: depth. Surface water, in equilibrium with and Parhippolyte sterreri, calanoid copepod The calanoid copepod £nantiosis atmospheric oxygen, is saturated, while Enantiosis bermudensis and halocyprid bermudensis has sister species inhabiting waters below the halocline in more isolated ostracod Spelaeoecia bermudensis. The anchialine caves in the Bahamas, Belize, caves vary from 56 to 78% saturation. calanoid copepocl Epacteriscus rapax and the Galapagos, Rji and Palau. The misophrioid Anchialine cave pools in Bermuda cyclopoid copepod NeocycJops stock; had copepod Speleophriopsis scottodicarloi fluctuate with the , but with reduced been described based on specimens from the belongs to a genus containing other amplitude and a delayed cycle in comparison Caribbean coast of Columbia before being anchialine cave species from the Balearic with open waters. Tidal amplitudes in caves reported from Bermuda caves. Islands, the Canary Island in the from 33 to 87% that of tides in open 2. Affinities with amphiatlantic and Old Atlantic, and Palau in the Western Pacific. waters, while lag times in the tidal cycle vary World taxa: Amphiatlantic organisms consist Two species of podocopid ostracods, from 9 to 151 minutes. of species inhabiting As was noted for Green Bay Cave, caves on opposite sides biological zonation varies with the proximity of the Atlantic Ocean. to the cave entrance and the strength of tidal The anthurid isopod currents. Analogous to terrestrial caves, the genus Curassanthura entrance or twilight zone of marine caves has three species: C. contain normal open water species typically bermudensis from found in shaded or protected habitats such Bermuda, C. canariensis as the underside of stones. Many fish and from the Canary Islands, lobster, for example, take up residence in the off the west coast of cave entrance zone. Farther into the cave in Africa, and C. halma areas of total darkness, food resources from the Caribbean become more limited and biomass decreases. islands of Bonaire and Strictly stygobitic (aquatic troglobitic) species Fig. 7: Mictocaris halope, a crustacean representing the new Curacao. order Mictacea, inhabits several caves in Bermuda and can predominate in the farthest interior regions Prior to their be regarded as a "living fossil."

NSS NEWS, August 2003 221 Number ofCaves by Parish, Bermuda

• Very Low , Low o Medium o High • Very High

~

Walllingham Cave o,!: Subway Cav.

",1_..

Walsingham ~" • Subwayea.... •• X xx• •• •• • • • - 6C..::...... ""'_""'·

Pollution Biologic • None Significance o Very Low • None o Low e Very Low o MedIum o Low o High o Medium • Very High o High • Very High

Wal.lngham Cave Walslngham Cave

Subwayelv. Subway Cave _. .. Iliffeoecia i1iffei and Paracypris crispa, are Bermuda (Fig. 6), includes stygobitic species predominantly stygobitic family known only from caves in Bermuda and an in the Caribbean, South Atlantic, Epacteriscidae. anchialine tube in the Galapagos Mediterranean and the Galapagos Islands. Islands. Likewise, the only two species 4. Affinities with deep sea taxa: Until their ORIGINS OF BERMUDA'S ANCHIALINE included in the podocopid genus Kare/oecia discovery from anchialine caves, misophrioid FAUNA inhabit caves in Bermuda and the copepods had been considered to be a deep A number of temporal and spatial origins Galapagos. sea group. Two species of misophrioids for the anchialine cave fauna of Bermuda In addition to the procarid shrimp Procaris inhabit Bermuda caves. have been proposed. Plate tectonics, chacei from Bermuda, the only other The new crustacean order Mictacea is stranding of species on the shoreline of a members of this genus inhabit anchialine represented by only three species: Mictocaris fossil sea, and coconut spreading or bird volcanic caves on in the ha/ope from Bermuda caves (Fig. 7), Hirsutia transfer are considered to be possible, but South Atlantic and Hawaii in the mid Pacific, bathyalis from 1000 m depth off the Atlantic unlikely, explanations as to how cave species as well as limestone caves on in the coast of and H. sandersetafia from first reached Bermuda. Caribbean. The atyid shrimp genus 1500 m depths in the Bass Straits between The cave shrimp of Bermuda as well as Typhlatya, represented by T iliffei in and Tasmania. other anchialine invertebrates may have had The colorless, transparent oligochaete three temporal derivations: (1) recent (from Using a GIS for Cave and Pha/lodrilus macmasterae from Bermuda is the Caribbean by way of the Gulf Stream ­ most closely related to P /obatus from bathyal e.g., Barbouria cubensis and Janicea Conservation in Bermuda (200 to 2000 m) depths on the continental antiguensis); (2) during the separation of the Bernie Szuka(ski slope off Surinam. African and American continental masses The islands of Bermuda, located in the 5. Affinities with interstitial/crevicular (e.g., Typhlatyajliffei); and (3) from Tethyan Western Atlantic Ocean approximately fauna: The archiannelid polychaete relicts which originated in the shallow tropical 1000 km off the coast of North Carolina, LeptoneriJIa prospera is the only species from sea that formed between the supercontinents contain many significant caves. Bermuda this group inhabiting marine caves. All other during the Triassic period, 205 to 250 million is a densely populated country with marine archiannelids, with the exception of years ago (e.g., Parhippo/yte sterreri). The approximately 65,000 inhabitants and a one deep sea species, are members of the transoceanic distributions of cave shrimps land area of roughly 57 square interstitial sand fauna. such as Procaris and Typh/atya as well as kilometers. Approximately 150 caves Judging from its minuscule size (0.25-0.27 other crustaceans including the amphipod have been discovered in Bermuda, many mm), the platycopioid copepod Nanocopia Pseudoniphargus and the mysid Stygiomysis of which are profusely decorated with minutaJTlay be of interstitial or crevicular suggest that such members of the anchialine delicate and unique speleothems. Many origins. The amphipod Ingo/fiella /ongipes, cave fauna of Bermuda and the Caribbean caves include passages which extend to described from only a single Bermuda may have originated before the opening of sea level and contain deep anchiaHne specimen, appears to have originated from the Atlantic in the Jurassic, 150 to 205 million pools and extensive underwater species inhabiting coastal interstitial waters. years ago. networks. A large variety of cave~ 6. Living fossil taxa: Such species are relict A possible deep-sea origin of the adapted life, including previously unknown species, have been found in fauna surviving only in restricted habitats that anchialine fauna is suggested by similarities these underwater caves. Of the species have served as a refuge. The isopod in fauna and environment between the two identified in Bermuda's caves 25 are At/antasellus cavernico/us is one of two habitats. In addition to caves, anchialine currently on the critically endangered species belonging to the family species list. The high population density Atlantasellidae. The platycopioid copepod and resultant development , Antriscapia prehensiJis, a very primitive vandalism, pollution and other negative species, shares many characters with the factors have significantly impacted and theoretical ancestral capepod. Mictocaris continue to threaten Bermuda's unique ha/ope from the new order Mictacea cave resources. (meaning "mixed or blended") is named for In early 2002 the Bermuda Cave and the common features it has with other Karst Information System (BeCKIS) peracarid crustacean orders. It may thus be project was established with the primary regarded as representing a missing link in the goals of increasing public awareness of evolution of the Crustacea. Bermuda's caves and cave life, increasing 7. Affinities with primarily stygobitic taxa: awareness of negative impacts on these Many of Bermuda's anchialine stygobites are resources, and promoting the scientific study of Bermuda caves. The BeCKlS members of genera or higher taxa utilizes GIS software from ESRI, one of characteristically inhabiting caves or the project sponsors, to maintain a groundwater. Included in this group are the database and inventory ofcave locations amphipods Bogidiella (Antillogidiella) and field observations. The GIS is being bermudensis, Pseudoniphargus grandimanus used to establish baseline quality and P carpaNs; isopods Arubofana aruboides information from past observations, and and Curassanthura bermudensis; to query and analyze the data and to misophrioid copepods Spefeophria bivexi/la understand relationships with other and Spe/eophriopsis scottodicarfoi; geographic and hydrologic factors. The halocyprid ostracod SpeJaeoecia development of a GIS database also bermudensis; and shrimp Barbouria facilitates the production of high quality cubensis, Typhlatya iliffei, Parhippolyte Fig. 8: Antecaridina lauensis is an atyid cartographic maps invaluable to record sterreri and Procaris chacei. Also noteworthy shrimp known from caves and other these features and understand their are the calanoid copepods Epacteriscus anchialine habitats in a number of wide Indo~Pacific significance and relationships (as in the rapax, Erebonectes nesioticus and Enantiosis spread locations across the color GIS images on the facing page). region. It was recently discovered from bermudensis which all belong to the a saltwater well in Bermuda.

NSS NEWS, August 2003 223 species have recently been found to inhabit 760 m depth have high permeability because In 2002, two of my graduate students, water-filled crevices and fissures within the of fractures and features and readily Rebecca Belcher and Darcy Gibbons, bedrock. Such a sub-sea level crevicular accept millions of gallons per day of obtained summer internships at the Bermuda habitat may extend to considerable depths wastewater. Less permeable carbonate strata Aquarium in order to begin cave-related in the ocean and provide a virtual continuum overlying the injection zones have been research projects. Rebecca is sequencing from inland caves to seamount slopes and counted on to contain the injected mitochondrial genes from the atyid cave potentially even to mid-ocean ridges. wastewater and prevent upward migration shrimp Antecaridina fauensis (Figure 8) in However, arguments against a deep sea of the wastewater and/or the resident saline order to compare widely spaced populations. origin include the presence of widespread water. However, at several sites upward This species was first reported from an anoxia in the deep sea during the recent past migration has been evidenced. anchialine cave in Fiji and later from Indo and phylogenetics evidence suggesting that The unique limestone/basalt rock Pacific locations, including the Hawaiian both cave and deep sea forms separately sequence in Bermuda is a quite different Islands, Marshall Islands, , evolved from common shallow water hydrogeological setting than Rorida, Thus, New Caledonia, Japan, Guam, Philippines, ancestors. problems of groundwater contamination that Madagascar and the Red Sea. Recently, have cropped up in Rorida are much more shrimp identified as this species were THREATS TO THE ANCHIALINE HABITAT likely to occur in Bermuda where the discovered from a 30 m deep saltwater well A number of environmental threats imperil injection wells are much shallower. Deep well in Bermuda. Rebecca has collected more anchialine caves, especially those in injection requires special investigation, than 40 specimens of Antecaridina from the Bermuda. Quarrying of limestone can be design, construction, operation, and Bermuda well and has successfully amplified particularly hazardous in that it not only monitoring in order not to present a major and begun characterizing the sequences of destroys caves but also disrupts groundwater groundwater pollution . three mitochondrial genes. We have also circulation patterns through the karstic In comparison to open water marine obtained Pacific specimens from caves in the aquifer. Furthermore, any stygobitic species environments, anchialine caves are uniquely Philippines, Guam and Marshall Island and in the caves in question are destroyed. Thus, sensitive to organic pollution. Due to the total will begin to sequence DNA from these large-scale activities and associated darkness inherent with caves, photosynthesis shrimp for comparison. This work should destruction of the cave habitat have the and resulting oxygen production does not provide insight into the timing and mode of potential to cause the of endemic occur. Also, the restricted connections of dispersal of this and other anchialine animals. species. Umestone quarries in Bermuda have these caves to open waters inhibit input of Darcy Gibbons is compiling an caused the complete destruction of a number oxygen from the sea. Thus, depleted levels environmental survey of each of the known of anchialine caves. of dissolved oxygen are characteristic of 150+ caves on the island, replicating a "Deep well injection" (to relatively shallow deeper cave waters. Addition of organic historical survey of these caves carried out depths of approximately 30 m or less) is being matter in the form of sewage, plant matter in 1983. The caves are being analyzed for used to dispose of sewage and wastewater or garbage to cave waters stimulates growth positive characteristics including in Bermuda. At least one Yucatan cave close of naturally occurring bacterial populations. speleothems, size, and biological and to an injection site has recently become These bacteria rapidly consume all available historical significance, as well as for negative polluted with brown, turbid water below the dissolved oxygen and subsequently produce threats including the extent of vandalism, halocline. Considering the ever-accelerating highly toxic hydrogen sulfide. Thus, organic water pollution, dumping or littering, and rate of development in many coastal areas pollution is extremely serious, inevitably quarrying or construction. When completed, within the tropics and the lack of proper leading to oxygen depletion, The loss of the current data will be compared to the controls, the potential for pollution of karst oxygen in cave waters due to pollution will historical data in order to analyze whether groundwater is enormous. result in suffocation of the aerobic cave the environmental status of the caves has Although deep well injection has been macrofauna. improved or worsened over the intervening used as a means of disposing of treated twenty years. Darcy is also analyzing cave sewage in South Florida, the process is CURRENT AND FUTURE RESEARCH water quality to determine whether there is controversial at best. The Roridan aquifer Collaborative cave research projects in significant water pollution such as excess system, which is used for water supply Bermuda are underway with several nutrients or fecal contamination. throughout most of Florida, is a thick scientists on diverse topics. In June 2002, In order to raise public awareness of the sequence of carbonate rocks. In South archiannelid polychaete worms were island's caves and cave animals and to Florida, the lower strata of the Floridan collected from Bermuda caves for study by document threats to this fragile habitat, the aquifer contain saline water. These strata at Katrine Worsaee of the University of Bermuda Cave and Karst Information Copenhagen. In these samples, Katrine has System (BeCKIS) has been erected as a found a new species that is highly specialized component of the Bermuda Zoological :l to the cave habitat. In an environment Society's Bermuda Biodiversity Project. dominated by crustaceans, we are finding a BeCKIS will locate and map caves and ~ ,,' I, variety of other cave-adapted invertebrates. compile data on their biological, geological, :2004 CAVERS CALENDAR In March 2003, specimens of the crustacean and hydrological. This information will be Mictocaris halope were obtained for Dr. entered, along with other biological, ~" , In~'O,O each '",.., Stefan Richter of Humbolt University in geological, topographical, land use, and Berlin. Stefan is examining the internal environmental data into a comprehensive ' S2.0__,Ping any qua~t,~ty..,~..",.~" anatomy of Mictocaris in order to better GIS database composed of interrelated layers PL~!lO determine the place of the order Mictacea that can be queried for various planning, , 47 Sl PRESLS ,.{",: within the Crustacea. On the same trip, ecological or conservation initiatives. .' Imestone ane..fa'~0t.'!:: ~ several already broken stalagmites were Driftwood, TX 78619 collected for use by Dr. Lloyd Keigwin of the For more information on anchia/ine caves 'ft"," , , " Woods Hole Oceanographic Institute in in Bermuda and elsewhere, please visit our testing theories on climate history in the website at: www.cavebiology.com ocean.

224 NSS NEWS, August 2003