Vanuatu is a Melanesian island republic in the south-west Pacific, consisting
of 80 islands spanning 850 km from 13°S to 22°S and covering 12,200 km2 (Anon.
1994) (see Figure 1). The country had a population of 186,000-200,000 (Loughman,
2001, SPC), with the 1999 census indicating a population of 186,678. Recent SPC
2008) were for a mid-2008 population of 233,026 and a mid-2010 estimate of
245,224 (and a 2008-2010 estimated growth rate of 2.6%). According to the World
Factbook the July 2008 population estimate is 215,446 with a 2008 growth
rate estimate of 1.434%. This is concentrated on 3 of the major islands, and a
total land mass of 1.2 M ha of which 41% is arable (Anon 1994). In 1990, the
agricultural sector contributed 23% of GDP and national exports continue to be
dominated by agricultural commodities, primarily copra and beef and to a lesser
extent cocoa and timber (Anon. 1994). Subsistence agriculture accounts for 43%
of agricultural production and 80% of working age ni-Vanuatu (indigenous
citizens) cultivate their own land for their livelihoods. The livestock sector
is dominated by beef cattle production and contributes 12% to GDP and 22% to
national exports. A national goat herd of 12,000 is reported but this figure may
be significantly overestimated. |
The national cattle herd is estimated to be approximately 140,000-150,000 of which 77,000 are owned by the smallholder sector (Macfarlane 1998) and the remainder by the plantation or large holding sector (>100 head of cattle) which includes both ni-Vanuatu and expatriate graziers. Larger holdings are concentrated on the islands of Efate and Espiritu Santo whereas smallholder cattle are widely dispersed but more prevalent on Espiritu Santo, Malo and Epi. The average ni-Vanuatu household owns 9 cattle, increasing to 13 on Espiritu Santo (Anon. 1994). Vanuatu has 2 export standard abbatoirs, based on Efate and Espiritu Santo, and exported 1,200 tonnes of beef in 1992, primarily to Japan, Papua New Guinea and Solomon Islands. Exports in 1999 and 2000 respectively were 1577 and 1361 tonnes to Japan, Solomon Islands and Papa New Guinea and following a trade arrangement in 1999, also to Fiji. 684 Mt in 2002, but rose again to 1,021 Mt in 2003 and 1,049 Mt in 2006. Approximately 20% of slaughtered cattle are sourced from ni-Vanuatu producers. Quite a number of cattle are sold by subsistence farmers to regional butcheries or to villagers for traditional ceremonies and feasts (Anon. 1994). Loughman (2001) indicates that around 16,000 head of cattle are slaughtered annually with approximately 7000 to 8000 being killed in rural areas for consumption.
Figure 1. Map of Vanuatu
|5. THE PASTURE RESOURCE
The plantation sector grazes 58,000 ha, of which 16,000 ha is under coconuts.
The pasture resource is 21,000 ha of improved grass pastures, 7,500 ha of
naturalized buffalo grass (Stenotaphrum secundatum), 7,000 ha of carpet
grass (Axonopus compressus) and T-grass (Paspalum conjugatum), and
the balance is partly cleared bush (Macfarlane et al. 1994a). The
productivity of the various pasture systems is dependent on edapho-climatic
conditions, the presence or absence of a legume component, and the degree of
weed invasion. Considerable pasture rehabilitation and development was
stimulated by the activities of the recent AusAID Vanuatu Pasture Improvement
Project 1988-1993 (Macfarlane et al. 1994b). |
Carpet grass and T-grass dominate the native/naturalised pastures of the high rainfall regions in combination with the naturalized legumes Mimosa pudica, Desmodium canum, and Desmodium triflorum. In low rainfall regions, Dicanthium, Bothriochloa and Heteropogon spp. dominate (Evans et al. 1992). Herbaceous and woody weeds seriously reduce the productivity of native pastures throughout Vanuatu (Mullen et al. 1993).
Open pasture systems
The principal improved pasture system in Vanuatu is signal grass (Brachiaria decumbens). Over 16,000 ha of signal grass has been planted, predominantly on expatriate plantations on relatively fertile interior soils in full sun (Evans et al. 1992). Liveweight gains of 0.4 kg/ha/day are common from cattle grazing legume-deficient signal grass and 0.5 kg/ha/day is readily achieved when a significant legume component is included (Macfarlane 1993).
A significant research effort was invested in identifying legumes that would persist in vigorous signal grass swards (Macfarlane et al. 1994a). Puero (Pueraria phaseoloides), Amarillo peanut (Arachis pintoi) and to a lesser exent centro (Centrosema pubescens) and Glenn and Lee joint vetch (Aeschynomene americana) were found to persist well. Some problems with puero dominance of pastures were experienced but this was controlled by short-term heavy grazing once puero dry matter reached a composition of 40% of the pasture.
Other pasture grasses well suited to the high rainfall areas are para grass (Brachiaria mutica), koronivia (Brachiaria humidicola), hamil, green panic and embu (Panicum maximum) (Table 2). Pasture mixtures of signal and Hamil guinea are compatible with twining legumes and have been highly productive.
In low rainfall regions, sabi grass (Urochloa mozambicensis) and Bothriochloa pertusa proved to be valuable grasses in combination with Seca stylo (Stylosanthes scabra), siratro (Macroptylium atropurpureum) and leucaena (Leucaena leucocephala). In the subtropical environment of Middle Bush, Tanna, kikuyu (Pennisetum clandestinum) combines productively with Shaw vigna (Vigna parkeri) and Safari white clover (Trifolium semipilosum). Stocking rates in Vanuatu range from 1.5 hd/ha in less fertile, lower rainfall sites (<1500 3.0="" fertile="" ha="" hd="" interior="" mm="" on="" soils="" to="" up="" with="" yr="">2200 mm rainfall. 1500>
Table 2. Liveweight gains for cattle grazing various pasture types in Vanuatu
Pastures under coconuts* not sustainable
The preferred pasture species for coconuts planted at 8-10m spacings is buffalo grass. Buffalo grass is extremely tolerant of high grazing pressure and tolerates the lower rainfall coastal environments where coconuts are typically grown (Mullen and Shelton 1996). Where coconuts are mature and light transmission is >70%, grasses such as sabi grass and signal grass can be grown. The alkalinity of the coastal soils reduces the range of suitable companion legumes. Glenn and Lee joint vetch (Aeshynomene americana), Desmanthus virgatus and siratro (Macroptilium atropurpureum) have all proved to be well adapted to coastal coralline pastures but none are as persistent, productive or as high quality as Leucaena leucocephala.
In 2003 a plot of Mulato grass (Brachiaria hybrid cv Mulato; produced at CIAT as the result of 14 years of research, being a cross between Brachiaria brizantha cv Marandu and B.ruziziensis 44-6; see <Grupo Papalotla>) was established for evaluation and multiplication on the Government Farm. Vegetative cuttings are being used to establish additional areas.
In 2004 a small area of Hybrid Napier (Pennisetum purpureum cv. Hawaiian Hybrid) was established (with canes from Tonga) for evaluation and multiplication for cut-and-carry feed for dairy animals.
|7. ORGANIZATIONS AND PERSONNEL INVOLVED IN PASTURE RESEARCH AND DEVELOPMENT There is no recurrent pasture research activity in the Vanuatu Department of Livestock or within the various research institutions. However, a considerable amount of pasture research activity was undertaken during the early 80s through the Vanuatu Pasture Improvement Project with AusAID support. Technical reports, technical bulletins and other materials published form the basis of the current research knowledge (Macfarlane and Shelton 1986, Macfarlane et al. 1994a and 1994b, Evans et al. 1992, Mullen et al. 1993, Mullen and Macfarlane 1998, Macfarlane 1998). The following Department of Livestock personnel have considerable practical knowledge of pasture research and development in Vanuatu|