Parajubaea sunkha

If the palm remains undisturbed it shows an abundant regeneration in its natural habitat, but overgrazing, land clearing, fires and human use of the palm’s fibres have a strong impact on the regeneration dynamics of this rare species (Vargas 1994).

On many sites the palm is a direct competitor to agriculture. The custom of felling the tallest trees when their productivity ceases, shows clearly that the palm will not be conserved unless it provides important socio-economic benefits to the farmers. This means that there is a dilemma between the usefulness and the subsequent overexploitation of the species, and the uselessness and clear cutting of the remaining populations.

See the Supplementary Material for figure 1: population structure of four representative palm stands.

A first inventory was carried out in January 2001. The diagrams of the forest inventory (fig. 1) depict the population structure of four representative palm stands of 1ha in size that belong to four different farmers. The diagrams show clearly that the population structure is unbalanced: while 2–5 years old palm plants are very abundant in all populations, the generation of 0.5 m tall palm trees is missing completely in populations P1 and P2 and is underrepresented in populations P3 and P4.

The absence of palms around 0.5 m of height (+/-20 years old) can be traced back to the construction of a road that connects the rural area with the town. Before the road was built, farmers transported the fibre with donkeys and on their backs to the local market. This limited them in terms of the quantity they could transport and secured the fructification of adult palms to ensure regeneration. Since the road was build in 1984, it is possible to harvest and transport much larger quantities of palm fibre. Farmers confirm that in this time almost all palms were under exploitation. As a result, regeneration almost came to a halt. This is shown by the absence of the 0.5 m tall palms in the populations 1 and 2 (fig. 1). These palm stands are directly linked to the road and as consequence were exploited heavily.

The populations 3 and 4 belong to farmers that live within about an hour walk from the road. As a result, exploitation in these palm stands was not as intensive and regeneration could occur to some degree. This is testified by the presence of more young palms between 0.5–1 m of height compared to population 1 and 2 (fig.1).

Utilization
The palm produces a fibre, which grows in its leaf axils and is locally used to make mattresses, ropes and saddle pillows. Apart from subsistence use these products are sporadically sold on local markets.

The leaves are used to manufacture hats, baskets and fans (Vargas 1994). Leafs and fruits serve as fodder for livestock. Furthermore, the species is internationally traded as ornamental plant.

There is not yet any in-situ conservation activity in place. The habitat of the palm is not covered by any kind of protected area.

Ex-situ conservation is provided by the Bolivian NGO “FAN-Bolivia” who has made efforts for in vitro propagation. Furthermore, seeds of the palm can be purchased on the internet from various ornamental palm dealers. This kind of trade, however, is not legally approved by international and Bolivian national legislation article 15 of the CBD (Convention on Biological Diversity) and the Decision 391 of the treaty of Cartagena (in Bolivia: Decreto supremo 24676, Art. 3).

Project proposals for in situ conservation are ready (FAN-Bolivia 2003), but lack of financing and the implementation of national legislation are hindering the proceedings.

In 2008, a second inventory will be carried out in order to re-asses the status of conservation of the species