Investigation of the Hawaiian Traditional Fish Poison Plant ‘Auhuhu, and the Viability of Its Use Today as a Fish Anesthetic Leina‘ala Bright1*, Levon Ohai1, Clyde S. Tamaru2, Bradley K. Fox2, RuthEllen Klinger-Bowen2,

Kathleen McGovern-Hopkins2 and Hi‘ilei Kawelo3. Kamakakūokalani Center for Hawaiian Studies1, Department of Molecular Biosciences and Bioengineering2, Paepae o He‘eia3

Materials and Methods

Experiments were conducted at Windward Community College’s Aquaculture/Aquaponic Research and Extension Center based on a report by Küҫük (2010) using fasted juvenile Blue Tilapia (Orechromis aureus), weighing between 5-15g. Raw ‘auhuhu seedpods were pounded using a mortar and pestle, and a stock solution was diluted directly with tap water into 10 L aquaria. Each dose was added to 2 groups of five fish (duplicate). Stock solution and recovery buckets were well aerated. Water quality parameters routinely monitored were DO and pH, without any significant difference throughout the duration of the experiment. Following timed exposure the fish were removed into recovery buckets to record the induction and recovery time of each dose. The induction time was recorded at the initial loss of equilibrium as the fish began to swim vertically. Recovery time was recorded when equilibrium was regained. Following recovery, fish were observed for 96 hours for adverse affects.

References Abbott, I. A. Laau Hawaii: Traditional Hawaiian Uses of Plants. Honolulu: Bishop Museum Press, 1992. p. 225. Chaudhari, T. B. Phytopharmacolgy of Tephrocia puropurea Pers. (Fabaceae)- A Review. IJPI’s Journal of Pharmacognosy and Herbal Formulations, 2012. http://www.ijpijournals.com Küҫük, S. Efficacy of Tricaine on Peocilia latipinna at Different Temperatures and Concentrations. African Journal of Biotechnology Vol. 9(5), 2010. p. 755-759. http://www.academicjournals.org/AJB Stokes, J. Fish-Poisoning in the Hawaiian Islands. Occasional Papers of the Bernice Pauahi Bishop Museum of Polynesian Ethnology and Natural History. Honolulu: Bishop Museum Press, 1921 p. 3-17.

Acknowledgements SEED/McNair Student Achievement Program, Grant No. P217A090206

College of Tropical Agriculture and Human Resources, USDA-ARS Agreement No. 58-5320-8-392

Traditional Application This project revives a traditional fishing practice known as hola, it signifies the plants prepared for fishing, as well as this type of fishing technique . Hola was used in fresh-water streams, on reefs, along rocky shores and in tide pools. The plants commonly used were ‘auhuhu (Tephrosia purpurea) and akia (Wikstroemia sp.) both were used traditionally for medicine as well. The plants were prepared quickly by pounding with a stone or by mortar and pestle, as the strength of the poison rapidly dissipated, losing its effect. It was believed the odor emanating from the freshly crushed vegetation was what affected the fish. When used in streams, a dam would be built and the hola placed in the water directly above the dam. Along the shores and the reefs, the hola would be placed in loosely woven grass hīna‘i (baskets) or placed in a sheath of niu (Cocos nucifera, coconut) when it was dispersed in tide pools to avoid being bitten by eels. Within a few minutes the fish would show the effects of the poison by swimming aimlessly or floating up to the surface . They were easily caught by hand or with dip nets and were safe to eat as the poison only left a bitter taste in the entrails of the fish which were discarded (Stokes 1921: 225).

Conclusion • This once common powerful plant is now extremely rare in the main Hawaiian islands and with its many

valuable qualities it is worthy of propagation and conservation. • As a medicine, this plant has been used over many centuries by Native Hawaiians externally for skin

diseases and internally as a tonic and relaxant when added to other remedies. • The extended period from induction to recovery observed in the current study (16 to 30 min) is

advantageous in the field of aquaculture for handling and surgical procedures as compared to the most commonly used anesthetic, MS-222 (1.5 to 3 min).

• The minimal costs, convenience, ease of propagation, preparation and implementation of this organic plant material offers a valuable alternative to synthetic anesthetics currently used in the aquaculture industry.

• As a fish poison, ʻauhuhu shows potential for the eradication of invasive species in our loko iʻa (fishponds), kahawai (streams) and along the reefs and warrants further investigation.

Abstract ‘Auhuhu (Tephrosia purpurea) is a Polynesian introduced plant, used by Native Hawaiians in a system of fishing called hola. The ‘auhuhu plant, which contains the chemical tephrosin, was traditionally pounded and scattered in tide pools, stunning fish and making them easily caught by hand or net. The objectives of this project are: 1) establish the lowest effective anesthetic dose of raw extract of ‘auhuhu: 2) establish optimal induction and recovery times for each dose and overall survival of fish which was found to be a concentration of raw extract at 0.2g/L and an exposure time of 30 seconds. This project demonstrates a valuable and viable alternative to addressing natural resource management from a Hawaiian perspective. Ko mākou mau kūpuna o Hawai‘i, our ancestors of Hawai‘i continually demonstrate the importance of living in harmony with spirit, man and nature. Integration of traditional ecological knowledge in modern research and education affirms its necessity in providing alternatives for the many challenges we face today in striving to become better stewards of our land.

'Auhuhu (Tephrosia purpurea)

Kumu Levon Ohai “E Kū Makani “

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Preparing the Hola Applying the Hola Preparing the grass hīna‘i

Bernice Pauahi Bishop Museum of Polynesian Ethnology and Natural History , Vol. VIII, No 10 with Plates XVII, XVIII

Introduction The investigation of the ‘auhuhu plant was prompted by the desire to promote the propagation and conservation of Hawaiian and other medicinal plants using aquaponic technologies. Through the Waihona Lā‘au Lapa‘au Project ongoing research has encompassed the holistic investigation of medicinal plants and their varied uses by Native Hawaiians. This plant shows excellent reproductive growth in the aquaponic environment, prompting further investigation into its various uses as an herbal medicine as well as a fish anesthetic and poison. ‘Auhuhu has antibacterial, anticancer, antioxidant, anti-inflammatory, antiulcer and wound healing qualities (Chaudhari, Vol 2:8, 2012). Defining the fine line between ‘auhuhu as a fish anesthetic as opposed to a poison offers alternatives for aquaculture research, operations and natural resource management. A natural, easily accessible and inexpensively produced anesthetic that reduces stress and physical injury of fish during weighing, tagging, measuring, transporting, surgery and other handling procedures is valuable. The chemical tephrosin, a natural rotenoid, administered in high doses and with prolonged exposure will result in the paralyzing of fish leading to death. Tephrosin does not have an effect on mammals and amphibians (Abbott 1992:86).

Blue Tilapia Juveniles Anesthetized

Propagation in Aquaponics System

Summary • The potency of raw ʻauhuhu extract in static experimental systems was found to decrease remarkably

within 2 hours of preparation. • Traditionally prepared ʻauhuhu was found to be an effective anesthetic at concentrations that are

comparable to commercial products. • Upper or lethal (0.4g/L) and lower or sub lethal (0.2g/L) concentrations of aqueous ʻauhuhu extracts were

established in this study for tilapia. • While there was no consistent effect on dose and time on induction, recovery appeared to be dependent

on time of exposure. • Time of exposure was found to be crucial in survival; the difference between 15 seconds of exposure

resulted in 5 fold difference in survival.

Blue Tilapia (Orechromis aureus)