# Makauwahi Cave

The Makauwahi Cave is the largest limestone cave found in Hawaii. It lies on the south coast of the island of Kauaʻi, in the Māhāʻulepū Valley close to Māhāʻulepū Beach, and is important for its paleoecological and archaeological values. It is reached via a sinkhole and has been described as “…maybe the richest fossil site in the Hawaiian Islands, perhaps in the entire Pacific Island region”.

## History

Though known historically by the inhabitants of the island, and used as a grave site by ancient Hawaiians, the cave’s paleontological value was first realized in 1992 by David Burney, Lida Pigott Burney, Helen F. James and Storrs 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” in Hawaiian, was rediscovered in 2000 by a local archaeologist, William Pila Kikuchi, who found the name in a high school student’s essay written over a century previously.
In 2004 the Burneys acquired a lease on the cave property, now the 17 ha (42.0 acres) Makauwahi Cave Reserve, which is subject to environmental restoration after having been used for sugarcane and maize farming before being abandoned to weeds. The area is being planted with threatened native plants, such as the local Pritchardia palm.

## Description

The site is apparently geologically unique in the Hawaiian Islands, comprising a sinkhole paleolake in a cave formed in eolianite limestone. The paleolake contains nearly 10,000 years of sedimentary record; since the discovery of Makauwahi as a fossil site, excavations have found pollen, seeds, diatoms, invertebrate shells, and Polynesian artifacts, as well as thousands of bird and fish bones.
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 since first Polynesians, and later Europeans and Asians, arrived in the islands and introduced to them a suite of invasive alien species such as Feral pigs and Feral dogs, Feral cats, Norway rats, Asian tiger mosquitos, and the Indian mongoose. They reveal the existence of a large number of native birds that became extinct as a result. The cave has also shown that certain plants previously believed to be Polynesian introductions, such as Kou (Cordia subcordata) and Hala (Pandanus tectorius), existed on the islands prior to human settlement.
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 giant flightless species of the group Anatidae/ducks and geese, such as the turtle-jawed moa-nalo (Chelychelynechen quassus), and the Kaua'i mole duck (Talpanas lippa). Other extinct birds found in the reserve include the Kauaʻi palila (Loxioides kikuichi), the kaua'i o`o (Moho braccatus) the kaua'i Stilt-owl (Grallistrix auceps) the Wahi grosbeak (Chloridops wahi), and the Hoopoe-billed 'akialoa (akialoa upupirostris) Other species that have gone extinct who's remains have been found in the reserve include the Blackburnia burneyi beetle, and several species of Carelia (gastropod) snails. While the fossil remains of currently extinct species such as the mole duck, stilt owl, and Kauai Palila have been found in the cave, the remains of the Locally extinct Laysan teal, and Hawaiian hawk have been found in the cave as well.
The Kauaʻi cave wolf spider, and the Kaua'i cave amphipod are only known to occur in the caves of Kauai and in only a few lava tubes in the area. Also in the park outside of the cave is an enclosure for 17 sulcata tortoises from Africa that are being used to control introduced invasive species of weeds that brought to the island by people such as the Paederia foetida, Paspalum conjugatum, Mimosa pudica, and megathyrsus maximus, as a Pleistocene rewilding substitute for the extinct giant flighless ducks and geese that used to live there. Several endangered species of birds that are coming back to the different restoration areas of the park such as the Black-crowned night heron, subspecies N.n. Hoactil, Hawaiian duck, Hawaiian gallinule, Hawaiian stilt, Hawaiian coot, and the Hawaiian goose, also called the nene. Native plants such as the Melanthera micrantha, Sesbania tomentosa, Hibiscus clayi, scaevola taccada, Capparis sandwichiana, and Eragrostis variabilis are also repopulating the area, while native trees such as Kokia kauaiensis, and several Kauai native Pritchardia trees are being replanted in areas where they once grew. The Makauwahi cave reserve also has a habitat for shorebirds such as the Migratory Pacific golden plover, the Wandering tattler, and the Ruddy turnstone subspecies A.i. Interpres. As well as a coastal beach habitat for Hawaiian monk seals, and Green sea turtles, as well as seabirds such as the endangered Hawaiian petrel, the Newell's shearwater, and the Great frigatebird subspecies F.m. palmerstoni.