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Polynesian-South America Round Trip Canoe Voyages Ben Finney University of Hawai'i

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Polynesian-South America Round Trip Canoe Voyages Ben Finney University of Hawai'i Rapa Nui Journal: Journal of the Easter Island Foundation Volume 8 Article 2 Issue 2 Rapa Nui Journal 8#2 June 1994 1994 Polynesian-South America Round Trip Canoe Voyages Ben Finney University of Hawai'i Follow this and additional works at: https://kahualike.manoa.hawaii.edu/rnj Part of the History of the Pacific slI ands Commons, and the Pacific slI ands Languages and Societies Commons Recommended Citation Finney, Ben (1994) "Polynesian-South America Round Trip Canoe Voyages," Rapa Nui Journal: Journal of the Easter Island Foundation: Vol. 8 : Iss. 2 , Article 2. Available at: https://kahualike.manoa.hawaii.edu/rnj/vol8/iss2/2 This Research Report is brought to you for free and open access by the University of Hawai`i Press at Kahualike. It has been accepted for inclusion in Rapa Nui Journal: Journal of the Easter Island Foundation by an authorized editor of Kahualike. For more information, please contact [email protected]. Finney: Polynesian-South America Round Trip Canoe Voyages Polynesian-South America Round Trip Canoe Voyages Ben Finney, Ph.D. University ofHawai 'i The well-documented cultivation of the sweet potato in exposed Polynesian voyagers sailing in open canoes to the East Polynesia, plus the much more arguable pre-European cold, rough seas of the higher latitudes which could easily presence in Polynesia of other cultigens as well as some have broken up their vessels, or simply killed them through artifacts and human genes from South America, has been hypothermia. Departing from Rapa Nui would, of course, explained by various authorities as either the result of one­ greatly shorten such a voyage and therefore lessen the way raft voyages by South American sailors to Polynesia, or dangers to crew and canoe (Figure 1, route C). of two-way canoe voyages by Polynesian sailors to South Fortunately, Polynesian voyagers who had reached the America and return. Although the simplicity of imagining a edge oftheir island world and wanted to probe the apparently raft voyage from South America to Polynesia is appealing, island-less seas to the east had a number of warm water we should not dismiss the possibility that some particularly alternatives to dipping down into the higher latitudes to find daring Polynesian sailors might have made a round-trip westerly winds. In the long migration from the Asian side of voyage. In the last issue of this journal, George Gill (1994) the Pacific to the mid-ocean islands of Polynesia their proposed a round-trip between Polynesia and South America ancestors had learned how to exploit westerly wind shifts to that probably started in the Marquesas and ended up at Rapa sail to the east Each summer speIls of westerly winds Nui as one of three scenarios that would be consistent with periodically interrupt the easterly trade winds, particularly in his osteological findings of an apparent mixture of the western Pacific. The regular seasonal dominance of these Polynesian and South American features on Rapa Nui. Based westerlies in the seas betwe<:n New Guinea and FUi, Tonga, on my own thoughts on sailing to South America and back and Samoa may help to explain why pioneering Lapita contained in an article now in press in the Japanese journal voyagers were able to move so swiftly from the Bismarck Man and Culture in Oceania (Finney in press), I would like Archipelago to the edge of Polynesia. Although these to offer some comments on Gill's suggestion. summer westerlies become more episodic the farther east one If ever a Polynesian canoe reached South America, and sails across Polynesia, they were probably critical to provided the crew was able to refit it and lay in sufficient continued eastward migration from Samoa and Tonga to the stores, a return voyage would have been more than just archipelagos of central east Polynesia. Certainly, historical possible, for voyaging canoes excel at sailing with the wind-­ accounts, including one penned by Captain Cook, indicate in this case the southeast trades--blowing abaft abeam. It is that Tahitians and other eastern Polynesians waited for the the voyage from Polynesia to South America that appears to winds whenever they wanted to sail to the east. Given, present a much greater challenge. That is because it looks however, the great ocean gap between the archipelagos of like a canoe would have to beat for some four thousand of central East Polynesia and Rapa Nui, one wonders whether miles from the Marquesas, Tuamotu-Gambiers, or Australs, the settlers of Rapa Nui had been able to exploit episodes of or at least the 2300 miles from Rapa Nui, against steady these summer westerlies to sail all the way to this trades and accompanying currents to reach the continent. easternmost Polynesian island. Scenarios featuring canoes beating to windward are most There are at least two other westerly wind regimes that unrealistic, given the trigonometry of windward sailing. A might have been used by adventurous voyagers to sail to double canoe that can make good about 75° to windward Rapa Nui or perhaps even to South America (Finney 1993). would have to tack back and fOlth over almost four miles of During major EI Nino conditions the normal atmospheric ocean to make one mile directly upwind, a ratio that pressure gradient (high over Rapa Nui and low over increases markedly when sailing against a current, such as Indonesia) basic to easterly trade wind flow reverses (low that which usually accompanies the trades (Finney 1985). In over Rapa Nui and high over Indonesia) weakening the this light, the direct sail from the Marquesas to South trades and bringing outbreaks of strong westerlies that reach America pictured in the end paper of Buck's Vikings ofthe far across the Pacific. During the last major EI Nino, that of Sunrise (see Figure I, route A) seems highly implausible. 1982-1983, the weather station at Rapa Nui recorded Sailors in the age of the square-riggers recognized this frequent westerly winds (Caviedes and Wayland 1993), problem, and avoided trying to beat windward against the suggesting that under such conditions a canoe could have trades. In the nineteenth century sailing manuals, for sailed directly from the Marquesas to Rapa Nui. example, the recommended route from the Marquesas to Furthermore, since these EI Nino westerlies probably spread Valparaiso takes a ship on a roundabout course south out of much farther to the east than Rapa Nul, perhaps some time the trade wind belt and into the higher latitudes where in the past a similarly massive outbreak of such winds might westerlies prevail, and then east to run directly to the coast of have enabled a group of Marquesans or other East Chile before these westerlies (Labrosse 1874, Figure 1, route Polynesians to sail directly to South America. B). However, the eastbound leg of such a route would have East Polynesians living farther to the south might have Rapa Nui Journal 33 Vol 8 (2) June 1994 Published by Kahualike, 1994 1 Rapa Nui Journal: Journal of the Easter Island Foundation, Vol. 8 [1994], Iss. 2, Art. 2 Rapa Nui (Easf---r Island) _...... (C)/- .... ---(D)---~-- ~ /(. , I.-A .. ~ '- ~ __.~ -':~olparoiso ----.. -- ----- ~ ---------~ Figure J. Some routes between Polynesia and South America. A: Peter Buck's direct canoe route from the Marquesas and return; B: the recommended square-rigger route from the Marquesas to Valparaiso; C: a high latitude westerlies canoe route from Rapa Nui to the coast; D: a winter westerlies canoe route directly ji-om Rapa Nui to the coast (Finney In Press). been able to work their way to South America by another trade wind zone to another, making us wonder about the way: exploiting spells of westerlies that occur episodically possibility of using this counter current flow to work our way during the winter along the southern fringe of Polynesia. to South America. Some sixty years ago, the French When low pressures systems that normally pass well to the adventurer Eric de Bisschop had also become intrigued with south of the trade wind belt are displaced to the north, the possibility that the ancestors of the Polynesian had troughs extending northward from these lows cut through the exploited this Equatorial Countercurrent, only he saw it as trade wind field, bringing brief spells of westerly winds in the key to understanding how they had managed to sail, their wake. In 1986 Hokule 'a was sailed from Samoa to against the trade winds, from Southeast Asia to Polynesia He Tahiti, directly against the direction of the prevailing trade was living in China at the time, and decided to try to use this wind flow, by exploiting a succession of such episodes of current to work ajunk all the way to Polynesia to confirm his winter westerlies (Finney et a!. 1989). theory. Unfortunately, De Bisschop discovered what Just as these winter westerlies may have been used by oceanographers have since confirmed: there is no monolithic voyagers who reached Rapa Nui, so might others have counter current, just a narrow band where jets ofcurrent flow employed them to sail from the Southern Cooks, Australs, or fitfully to the east. After struggling for months to gain Mangareva to South America. Alternately, eastbound easting, he cut his attempt short and headed north for the explorers may have pushed off from Rapa Nui with a much Marshall Islands of Micronesia--only to be arrested by the greater prospect of exploiting these westerlies all the way to suspicious Japanese occupiers of the islands (De Bisschop continental shores, since the gap between Polynesia and 1939:5-6). South America is narrowest at this point (Figure 1, route D). A few years after I read about De Bisschop's attempt I Gill (1994: 17) has proposed still another way to sail to talked with oceanographers at the Scripps Institute of South America: by exploiting the eastward flow of the Oceanography about the possibility that Polynesians might Equatorial Countercurrent.
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