 Makauwahi Cavesinkhole, 2015 | |
  Makauwahi Cave Location in Hawaii | |
| Location | South coast ofKauaʻi island, Māhāʻulepū Valley |
|---|---|
| Region | Hawaii |
| Coordinates | 21°53′18″N159°25′8″W / 21.88833°N 159.41889°W /21.88833; -159.41889 |
TheMakauwahi Cave is the largestlimestone cave found inHawaii. It lies on the south coast of the island ofKauaʻi, in the Māhāʻulepū Valley close toMāhāʻulepū Beach, and is important for itspaleoecological andarchaeological values. It is reached via asinkhole and has been described as “…maybe the richest fossil site in theHawaiian Islands, perhaps in the entirePacific Island region”.[1]
Though known historically by the inhabitants of the island, and used as agrave site byancient Hawaiians, the cave’s paleontological value was first realized in 1992 by David Burney, Lida Pigott Burney,Helen F. James, andStorrs L. Olson, who found the cave’s access sinkhole while searching for fossil sites on the south coast of Kauaʻi. The traditional name of the cave, Makauwahi, or “smoke eye” inHawaiian, was rediscovered in 2000 by local archaeologist William Pila Kikuchi, who found the name in a high school student’s essay written over a century previously.[1]
In 2004 the Burneys acquired a lease on the cave property, now the Makauwahi Cave Reserve, spanning 17 ha (42.0 acres). The land is subject toenvironmental restoration after having been used forsugarcane andmaize farming before being abandoned toweeds. The area was previously being planted withthreatenednativeplants, such as the localPritchardia palm.[1][2]
In 2024 it was announced that due a lack of funding Makauwahi Cave would close to the public and ownership would be passed to Grove Farm, a Kauaʻi-basedland-developmentcompany. Since this announcement, three of the reserve's seventeenSulcata tortoises used to keep back encroachinginvasive plants have been reported missing.[3]
The site is apparently geologically unique in the Hawaiian Islands, comprising asinkhole paleolake in a cave formed ineolianite limestone. The paleolake contains nearly 10,000 years ofsedimentary record; since the discovery of Makauwahi as a fossil site, excavations have foundpollen,seeds,diatoms,invertebrate shells, andPolynesian artifacts, as well as thousands of bird and fish bones.[1][4]
The findings document not only the conditions before human colonization of the Hawaiian Islands, but also the millennium of human occupation with the drastic ecological changes that occurred sincefirst Polynesians, and laterEuropeans andAsians, arrived to the islands and introduced a suite of invasive species such asferal pigs,feral dogs,feral cats,Norway rats,Asian tiger mosquitos, and theIndian mongoose. The reserve reveals the existence of a large number of native birds that became extinct as a result.[1] The cave has also shown that certain plants previously believed to bePolynesian introductions, such as kou (Cordia subcordata) and hala (Pandanus tectorius), existed on the islands prior to human settlement.[5]
Remains of some 40 species of birds have been found in the cave; half of these species are now extinct. New discoveries of extinct species include giantflightless species of the groupAnatidae (ducks andgeese), such as theturtle-jawed moa-nalo (Chelychelynechen quassus) and theKauaʻi mole duck (Talpanas lippa). Other extinct birds found in the reserve include theKauaʻi palila (Loxioides kikuichi), theKauaʻi o`o (Moho braccatus) theKauaʻi Stilt-owl (Grallistrix auceps) theWahi grosbeak (Chloridops wahi), and theHoopoe-billed ʻakialoa (Akialoa upupirostris) Other extinct species with remains found in the reserve include the beetleBlackburnia burneyi and several species ofCarelia snails. The remains of thelocally extinctlaysan teal andHawaiian hawk have also been recovered.[1]
TheKauaʻi cave wolf spider and theKauaʻi cave amphipod are only known to occur in the caves of Kauaʻi and a few lava tubes in the area. Also in the park outside of the cave is an enclosure for seventeenSulcata tortoises fromAfrica used to control introduced invasive species of weedsintroduced by humans to the island, such asPaederia foetida,Paspalum conjugatum,Mimosa pudica, andMegathyrsus maximus. These tortoises function as aPleistocene rewilding substitute for the extinct giant flightless ducks and geese that used to live in the area. Several endangered species of birds are returning to certain areas the park, such as theblack-crowned night heron subspeciesN.n. hoactil,Hawaiian duck,Hawaiian gallinule,Hawaiian stilt,Hawaiian coot, and theHawaiian goose, also called the nēnē. Native plants such as theMelanthera micrantha,Sesbania tomentosa,Hibiscus clayi,Scaevola taccada,Capparis sandwichiana, andEragrostis variabilis are also repopulating the area. Native trees such asKokia kauaiensis, and several Kauaʻi-nativePritchardia trees have been replanted in areas where they once grew. The Makauwahi Cave Reserve also has a habitat forshorebirds such as the migratoryPacific golden plover, thewandering tattler, and theruddy turnstone subspeciesA.i. interpres. There is also a coastal beach habitat forHawaiian monk seals andgreen sea turtles, as well asseabirds such as the endangeredHawaiian petrel, theNewell's shearwater, and thegreat frigatebird subspeciesF.m. palmerstoni.[6]