EPFL | ENAC | IA Laboratory of construction and architecture Rapa Nui Superstudio
10 Natural resources Prepared by: Ricardo Serpell, André Ullal, September 2018.
10.1 Agriculture
Until the first half of the 20th century, the isolation of the Island forced its inhabitants to be self- sufficient in procuring their food. Nowadays the sector has receded in favour of tourism and it is unable to supply the local demand. In 2016, 2,111 tons of perishable food and 2,199 tons of food were transported by airplane and ship, respectively [1]. As the former community-based extended-family microeconomic organization evolves into a nuclear-family based one, the population relies more on buying in the local commerce to supply themselves with food. Nevertheless, in the Carrying Capacity Poll carried out in 2016, 52.2% of the households declared maintaining a permanent family orchard (responds: always or almost always), compared to 37.1% that declared never having pursued it [1].
Due to increased produce and people arrivals from the continent and from the rest of Polynesia, several pests affected agricultural production on the Island in the 1970s. The use of pesticides was significant between 1975 and 1978, with widespread fumigations performed on a weekly basis [2].
In 2007, only around 180 hectares were under crop cultivation (aprox. 1% of the total land area) on 195 land holdings [3]. All cultivation was small scale and for local consumption. Only 12.2 hectares were recorded as irrigated. The main crops were: vegetables (43% of cultivated area), fruits (30%) and legumes and tubers (22%). The fraction of land used for tubers had decreased compared to previous census findings [4]. In comparison, a study of historic cultivation on the island suggests that tubers were the main crops: sweet potato, taro and yam [5].
Observations suggest that the total cultivated area has been increasing. In 2016, 798 hectares were identified as being used for agriculture (aprox. 4.8% of the total land area) [1]. In satellite imagery, cultivation appears to be concentrated to the east and north-east of Hanga Roa. Uncultivated land in these areas provides scope for the expansion of crop production. Other land on the island outside the national park has been identified as suitable for cultivation [6]. In general, there are 4,850 hectares of land with soils classified as cultivable (classes II to IV). Best soils, classes II and III, account for 1,749 hectares (around 10.6% of total land area) [4]. On most years, precipitations exceed evapotranspiration enabling rainfed agriculture. However, inter-annual and seasonal variation in precipitation makes the use of irrigation a necessity if a steady production is to be expected.
10.2 Animal husbandry
Sheep rearing played a significant role in the Island’s history, with up to 70,000 head roaming freely on the island during the first half of the 20th century, when land was being leased to the CEDIP. Animal husbandry identified in the Censo Agropecuario 2007 [3] was limited to cattle (2,284 head) and horses (604 head). Notably, cattle pastures accounted for 2,284 hectares, or around 7% of the total land area and around 12% of the area outside the National Park.
Current husbandry practices are spontaneous and uncontrolled. Livestock usually trespass the limits of the private land holdings, grazing the land inside the national park with significant damage to the natural ecosystem and archaeological heritage [7,8]. Private installations, such as water wells, have EPFL | ENAC | IA Laboratory of construction and architecture Rapa Nui Superstudio been activated inside the national park, often in the proximity of the archaeologic heritage sites. In some cases, livestock owners have installed fences inside the national park land.
Livestock is considered a safety asset by a fraction of the Rapanui population that regards country life as outside the Chilean sphere of influence. It is a reserve of food as well as a reserve of exchange value in case of future needs, an investment and a source of social status [8]. Some individuals were reported to have over 200 free-ranging horses for “no apparent practical reason” [2]. Horses frequently enter rural roads and city streets posing serious risk for drivers and pedestrians. Livestock robbery is frequently denounced.
Burning of shrubs and grasslands to eradicate unwanted species and favour the development of pasture for livestock feeding is a common practice among animal tenants and farmers on Rapa Nui. The burnings favour erosion of the soil, particularly on sloped terrain.
Current land granting practices, based on the assignment of 5-hectare plots of land to Rapanui individuals, difficult the development of animal husbandry. Most plots don’t have access to water, and their size prevents efficient tenure of animals without supply of imported pastures.
10.3 Fishing
Archaeological evidence suggests that both onshore and offshore fishing was undertaken historically by the Rapa Nui, with various fishing implements and the bones of tuna, shark and swordfish found in excavations. Current data on official fisheries is not available for Rapa Nui. Based on historical data from the 1970s, national catch statistics, and statistics recording vessel movements catches in the Exclusive Economic Zone were estimated in the range 150-200 tonnes for 2010 [9]. In 2011, the National Fishing Service (SERNAPESCA) reported 123 artisan fishers and 31 boats operating from the island [10]. There are 5 small fishing harbours in operation on the Island: La Perouse (northeast coast), Vaihu (south coast), Hanga Nui (west coast near ahu Tongariki), Hanga-Roa Otai and Hanga Piko (both near Hanga Roa).
Figure 10.1 Location of the 5 coves and 10 main inner fishing grounds used by artisan fishers, including number of times each ground was mentioned by 37 fishers interviewed by Yañez et al., 2007 (from [10]). EPFL | ENAC | IA Laboratory of construction and architecture Rapa Nui Superstudio
The main species targeted are yellowfin tuna, snoek, Pacific rudderfin (Nanue), rainbow runner, glasseye, oilfish, deep-water jack and swordfish [10]. Several local species are fished from or near the coast. The Mahi-Mahi is fished by hand line in spring and summer. The Nanue is a staple fish in the local diet. It is fished year-round by diving with nets and using hand lines. Catches were estimated at around 1,000 kg per month in 2013 [11]. In addition to fish, corals and seashells are extracted for their touristic sale value. Around 50,000 units of a small seashell called Pure and around 1,000 units of coral are extracted annually in spring and summer to manufacture handcrafted ornaments [11]. A significant decline in the abundance of Pure has been reported as a consequence of the increase in its extraction rate [10]. Control over landings and resource management is complicated by conflicting perceptions of Chilean central fishing authorities and rules [12].
Figure 10.2 Nanue fish and Pure seashells extracted from the inner inshore (sources: www.easterisland.travel and www.greenreport.it, respectively).
The marine ecosystem around Rapa Nui contains a remarkably high percentage of endemic species for such a small and geologically new landmass [13]. In December 2010 the ‘Motu Motiro Hiva’ Marine Park was established around nearby islands Sala y Gomez, with an area of 150,000 km2. At Our Oceans Conference 2015, the Chilean government announced the creation of two additional marine reserves, including the Rapa Nui Marine Park, a 720,000 km2 protected area that encompass the former ‘Motu Motiro Hiva’ [14]. The park became a reality when it was favourably voted by the Rapanui community in September 2017 [15].
10.4 Forestry
The first eucalyptus plantations on the island were carried out in 1900, soon after the annexation to Chile. By then the island was destitute of larger trees, just as had been described by the first European explorers. In 1970 new forests were planted, again of eucalyptus. The initial intention was to source biomass for thermal electricity generation. The biomass generation project was never implemented, as it was deemed more effective to expand the existing diesel generation base instead. The eucalyptus wood finds little use on the Island. It is a fast-growing dense hardwood with an irregular grain that makes it difficult to mill, producing timber that tends to twist and check badly. Construction uses in the Island are limited to massive elements made with whole logs (mostly columns and beams). EPFL | ENAC | IA Laboratory of construction and architecture Rapa Nui Superstudio
Forestry identified in the Censo Agropecuario 2007 accounts for 252 hectares of eucalyptus plantations [3]. Most of the forested areas are included in the land to be segregated from the Vaitea farm to grant land titles to additional Rapa Nui families. Planted forests and vegetable cover in protected areas have been subject to frequent fires, particularly in the spring and summer months.
Recent plantations have been carried out in different parts of the Island in order to repair damaged ecosystems (native species) or control erosion processes (mostly introduced species) [16].
10.5 References
[1] Observatorio de Ciudades UC, Estudio de Capacidad de Carga Demográfica para el Territorio de Isla de Pascua - Etapa 3 - Fase 4, Santiago, Chile, 2017. [2] Ilustre Municipalidad de Isla de Pascua, Proyecto: Plan de Desarrollo Comunal, Hanga Roa, Chile, 2004. http://www.municipalidaddeisladepascua.cl/sites/default/files/Plan de Desarrollo Comunal.pdf (accessed July 12, 2018). [3] INE, Censo Agropecuario y Forestal 2007, (2007). http://www.ine.cl/estadisticas/censos/censo-agropecuario-y-forestal-2007 (accessed August 1, 2018). [4] Ingeniería Agrícola Ltda., Diagnóstico para el Desarrollo Integral de Isla de Pascua: Proyecto Piloto de Riego en Cultivos Hortofrutícolas V Región - Resumen Ejecutivo, Isla de Pascua - Santiago, Chile, 1998. http://bosques.ciren.cl/bitstream/handle/123456789/9647/CNR- 0137_3.pdf?sequence=1&isAllowed=y (accessed September 11, 2018). [5] C.M. Stevenson, T.L. Jackson, A. Mieth, H.-R. Bork, T.N. Ladefoged, Prehistoric and early historic agriculture at Maunga Orito, Easter Island (Rapa Nui), Chile, Antiquity. 80 (2006) 919– 936. https://www.cambridge.org/core/services/aop-cambridge- core/content/view/5D4C954B6DB796B76518976CEB36A4FC/S0003598X00094515a.pdf/prehi storic_and_early_historic_agriculture_at_maunga_orito_easter_island_rapa_nui_chile.pdf (accessed May 18, 2018). [6] J. Flores V., E. Martínez, Determinación de la Erosión Actual y Potencial de los Suelos en la Isla de Pascua. Informe Final - 2013, Santiago, Chile, 2013. doi:10.13140/RG.2.1.4919.2165. [7] P. Muñoz-Santibañez, A. Meza, Manejo Sustentable : La Clave en la Peninsula del Volcán Poike, Isla de Pascua, Chile For. (2016) 24–26. [8] J.A. Gisolf, La ganadería Rapa Nui: El inicio a la participación, Van Hall Larenstein, Velp, Netherlands, 2002. http://www.agricolturaconsapevole.it/sites/default/files/janneke_gisolf_- _lallevamento_del_bestiame_sullisola_di_pasqua.pdf (accessed September 12, 2018). [9] K. Zylich, S. Harper, R. Licandeo, R. Vega, D. Zeller, D. Pauly, Fishing in Easter Island, a recent history (1950 2010), Lat. Am. J. Aquat. Res. 42 (2014) 845–856. doi:10.3856/vol42-issue4- fulltext-11. [10] J.C. Castilla, E. Yáñez, C. Silva, M. Fernández, A review and analysis of Easter Island’s traditional and artisan fisheries, Lat. Am. J. Aquat. Res. 42 (2014) 690–702. doi:10.3856/vol42- issue4-fulltext-3. [11] Faseuno Consultores, Capítulo 1 - Memoria, Ajustes Al Plan Regul. Comunal Isla Pascua. (2018) EPFL | ENAC | IA Laboratory of construction and architecture Rapa Nui Superstudio
65. http://faseuno.cl/prisladepascua/wp- content/uploads/2016/07/0_INTRODUCCION_PRC_ISLA_DE_PASCUA.pdf (accessed July 12, 2018). [12] J.A. Aburto, C.F. Gaymer, Struggling with social-ecological mismatches in marine management and conservation at Easter Island, Mar. Policy. 92 (2018) 21–29. doi:10.1016/J.MARPOL.2018.01.012. [13] C.B. Boyko, The Endemic Marine Invertebrates of Easter Island: How Many Species and for How Long?, in: J. Loret, J.T. Tanacredi (Eds.), Easter Isl. Sci. Explor. into World’s Environ. Probl. Microcosm, Kluwer Academic / Plenum Publishers, New York, 2003: pp. 258–260. doi:10.1038/046258b0. [14] M. Wei-Haas, Chile Announces Protections for Massive Swath of Ocean With Three New Marine Parks, Smithson. Mag. (2018). https://www.smithsonianmag.com/science- nature/chile-protects-massive-swath-ocean-new-marine-parks-180968275/ (accessed July 24, 2018). [15] Institute of Marine Conservation, Rapa Nui Rahui Marine Protected Area, Atlas Mar. Prot. (2017). http://www.mpatlas.org/mpa/sites/68807896/ (accessed July 24, 2018). [16] A. Dubois, Plantas de Rapa Nui. Guía Ilustrada de la Flora de Interés Ecológico y Patrimonial. Umanga mo te Natura, Santiago, Chile, 2013. www.umtn-rapanui.com (accessed September 12, 2018).