Pacific Science (2000), vol. 54, no. 4: 345-363 © 2000 by University of Hawai'i Press. All rights reserved A Preliminary Checklist of the Flora of Rotuma with Rotuman Names! WILL MCCLATCHEY,2 RANDY THAMAN,3 AND SAULA VODONAIVALU3 ABSTRACT: The terrestrial flora of the Rotuma island group consists of over 500 species of indigenous and introduced plants. Although the environment of these islands has been higWy modified by the Rotuman people, areas of ancient forest have survived. We provide here a list of the taxa identified by ourselves and others from Rotuma in the Bryophyta, Microphyllophyta, Pteridophyta, Coniferophyta, and Anthophyta. ROTUMA IS A GROUP of 10 volcanic islands Rotuma Island is composed of at least 21 that was administered as part of the British small volcanic peaks (or hills) and craters Crown Colony of Fiji from 1881 until Fijian that provide many gentle slopes and some independence in 1970. Since 1970, Rotuma steep inclines but no peaks of substantial administratively has remained a part of the height. Valleys found in and between volca­ independent nation of Fiji. It is located at nic cones form a ring plain in the center of 12° 30' S, 177° 05' E, about 450 km north­ Rotuma. These are filled with rich soils de­ northwest ofthe main Fiji group and 400 km veloped from erosion of the surrounding hills southwest of Tuvalu (Figure lA). The indig­ (Laffan et al. 1982, Ladefoged 1993). Histor­ enous Polynesian population of Rotuma in ical accounts from the l800s emphasize the the 1996 census was 9727, with 2580 resident abundance of food and the high fertility of in Rotuma and 7147 living elsewhere in Fiji the interior valleys (ring plain) (Bennett 1831, (Fiji Bureau of Statistics 1996). Of Rotuma's Lesson 1839). No permanent rivers exist on 10 volcanic islands, the largest, with an area Rotuma (one does exist on Uea), but many 2 of about 44 km , is the main island, Rotuma temporary stream flows occur following fre­ (Figure IE). The island of Uea is the second quent storms. Areas without rich soils are largest island, having a surface area of just covered in more recent lava flows or, in lower over 1 km2. It is the highest island in the areas, mixtures of sand and nutrient-poor, group, with an elevation of 260 m. The other swampy soils. Rotuma's climate is tropical eight islands are currently uninhabited but oceanic with a fairly even distribution of serve as resource islands for the Rotuman rain throughout the year (although dry people and may have served as refuges for periods can occur), with an average rainfall certain elements of the native flora. A good of 335 cm (Woodhall 1987). Temperatures description of the geology of the islands has range from 22 to 33°C with an annual mean been provided by Woodhall (1987), but there of 26.7°C (Mueller-Dombois and Fosberg has been no published research yet to corre­ 1998). In general the climate supports a lush late the geology and geography with the dis­ growth of plants on all land features. tribution of Rotuman plants. St. John (1954) described Rotuma Island as largely converted to copra production, with the native forest being cleared. He de­ scribed two areas on Rotuma Island, Kilinga 1 Manuscript accepted 13 January 2000. and Pepjei, as well as the isolated island of 2 Department of Botany, University of Hawai'i at Uea as representing the only remaining areas Manoa, Honolulu, Hawai'i 96822-2279. 3Department of Geography, School of Social and of native forest. These areas had survived Economic Development, The University of the South because of the rugged terrain and lack of soil Pacific, P.O. Box 1168, Suva, Fiji. suitable for agriculture. This picture has not 345 346 PACIFIC SCIENCE, Volume 54, October 2000 A ~, ~o~, Tuvalu ". ...' '\10' Solomon Islands ~ . "" ..,. ~ .. ... Rotu.rna Wallls& Samoa ... Futuna'" '0." o· . ~ ~, ~j Vanuatu , .~,. ~. O·Fij~'.:: ll, ." :New Caledonia G' ,. Il... ... ~ .'" ., .... B () Uea t!JHatana 0. Haua'ti'u Malbaba o Haua'meamea (l,HoOl.a Itu'tl'u Pepjei Noata. fgaha (J c:::> a Solnobu Solkope FIGURE 1. A, The southwestern Pacific area. B, The Rotuma island group. changed substantially since St. John's field­ root crops, banana and plantain cultivars, work in 1938. However, "copra has declined and other planted and protected useful trees. in importance as a major source of income, Pig rearing, often within elaborate stone­ although it remains Rotuma's main export" walled pens, is also an integral component of (RenseI1994: 66). There has been, as stressed the agricultural system and has been recog­ by Clarke and Thaman (1993), development nized by Rotumans as having a considerable and maintenance of a polycultural agro­ impact on the vegetation, especially herba­ forestry system, employing a diversity of ceous understory species and species with A Preliminary Checklist of the Flora of Rotuma-MCCLATCHEY ET AL. 347 vulnerable juvenile stages. Human popula­ MATERIALS AND METHODS tion pressures on Rotuma have decreased over the last 30 yr with heavy migrations to Many botanists and other plant collectors Fiji, New Zealand, and Australia. The 1956 have visited Rotuma, recording their obser­ census reported a population of 2993 Rotu­ vations and preparing herbarium vouchers. mans on Rotuma (as cited in Rensel 1997). The following individuals are known to have In 1991, during our research, the population collected from Rotuma: George Bennett, was estimated by the District Officer to be at Todd Capsin, William Clarke, Paul Cox, around 2500 people. Evidence of a substan­ J. Stanley Gardiner, D. Hassall, V. Kauvale, tial level of depopulation over the years is Harley Manner, Will McClatchey, Antoine widespread, with many vacant houses, open N'Yeurt, Michael Stevens, Harold St. John, house foundations, and fallow gardens being Randy Thaman, John Thurston, Saula found throughout the island. This is partially Vodonaivalu, A. K. Waqatabu, and Arthur due to population migrations and partially Whistler. In addition, specimens have been due to changing from traditional to modern found in several herbaria with no collector housing (Rensel 1997). listed, and a Fiji Department of Agriculture The earliest European botanical explora­ number has been assigned to the specimens. tion of the islands occurred less than 2 yr The main research by McClatchey, Tha­ before 1831, when George Bennett stayed for man, Vodonaivalu, Clarke, and Manner took a short period on his way to Australia (Ben­ place in conjunction with several of the other nett 1831, 1860). Other early plant collectors listed researchers beginning in 1985 and end­ who visited Rotuma and provided limited ing in 1994, with about 8 months being spent comments on the flora during the 1800s were in the island group. As part of our continuing Sir John Thurston (undated manuscript, studies of culturally important plants, we "Ramble on Rotuma," in Thurston private surveyed all major terrestrial ecosystems in papers, Fiji National Archives, Suva) and J. each of the seven political districts of Ro­ Stanley Gardiner (Gardiner 1898). Terres­ tuma: Noa'tau, Oinafa, Malhaha, Itu'muta, trial botanical literature from Rotuma is Itu'ti'u, Juju, and Pepjei (Figure lB). Plant largely limited to the published and un­ specimens were collected as encountered in published results of St. John's 1938 trip to nonvillage settings. Some plants of notable the islands (St. John 1938a,b, 1954, 1970a,b, cultural importance were also collected from 1975, n.d., Bartram 1943), very short agri­ within villages, but most ornamentals were cultural reports (parham 1941, Hartley 1963, not. Each of the islands was visited although Brodie 1982), and ethnobotanical studies most collection time was dedicated to Ro­ (McClatchey and Cox 1992, McClatchey tuma and Uea. Our voucher specimens were 1993a,b, 1996a,b, Thaman and Clarke 1993). added to those of previous work already Although Rotuma is politically part of Fiji, found in herbaria (BISH, H, K, SUVA, and us). it was specifically excluded from the most Names for plants were provided by Rotu­ recently published flora of Fiji (Smith 1979, man collaborators. Names were either freely 1981, 1985, 1988, 1991) and from the floristic assigned in the field by Rotuman guides or inventory of Fiji (Ash and Vodonaivalu were assigned in village group sessions with 1989). In addition to studies of terrestrial Rotuman elders reviewing specimens, dis­ plants, identification of the surrounding reef cussing names, and reaching a consensus. All algae has been carried out by N'Yeurt names recorded are the result of at least two and South (N'Yerut 1993a,b, 1995, 1996, independent reports of the same name. In South and N'Yeurt 1993, South et al. 1993, some cases a plant name was only provided N'Yeurt et al. 1996). The study reported here by a single informant. These names have not is limited to terrestrial botany with the ex­ been included. In a few cases two different ception of angiosperms that have invaded the names were each independently verified so marine environment. we have chosen to report both. The written 348 PACIFIC SCIENCE, Volume 54, October 2000 Rotuman language system incorporates a CassythaceaejLauraceae, CuscutaceaejCon­ system of diacritical marking on many of the volvulaceae, PunicaceaejLythraceae, Ver­ vowels. These have been omitted but in many benaceae jLamiaceae, and the families of cases can be found by referencing the Rotu­ Liliopsida [sensu Cronquist 1988]). man dictionary (Inia et al. 1998). DISCUSSION RESULTS The taxa listed in Appendix 1 indicate an The checklist of Rotuman plants (Appen­ overwhelming majority of angiosperms. The dix 1) is a compilation of the herbarium ferns (St. John 1954) compose the next most sheets available in the acknowledged her­ common group, with only a few bryophytes baria as well as our own private collections, having been identified.