Can oil palm plantations become bird friendly?

Abstract

Despite the increasing claims that structural complexity in agroforestry plantations is a key variable for enhancing bird biodiversity, few studies have experimentally manipulated the understory component of structural complexity. Here, we examined the impact of removing understory vegetation from oil palm plantations on the richness and abundance of birds in eastern Guatemala, testing if bird richness and abundance are positively affected by the presence of understory vegetation. Oil palm plantations with understory hold more bird richness and abundance than those lacking it. The experimental removal of this vegetation, equivalent to a reduction in complexity, decreases bird richness but not abudance. Our analysis shows clear effects of vegetation removal on bird richness, such that removal reduces richness and abundance to levels found in areas without understory. Hence, leaving or implementing structural complexity within plantations could satisfy the current need of making commodity production a cleaner industry, fulfilling both, the production of highly demanded commodities and the conservation of biodiversity in productive landscapes. Oil palm (Elaeis guineensis) is one of the most rapidly expanding crop in tropical regions, representing the major cause of loss of natural forests and of the decline of endangered species in several countries. Enhancing understory vegetation might reduce such negative effects. This is one of the few experimental tests about how a component of the vegetation and structural complexity of plantations affects birds.Fundacion Defensores de la Naturaleza; AGCI (Agencia de Cooperacion Internacional de Chile

Providing Habitat for Native Mammals through Understory Enhancement in Forestry Plantations

“…Understory of plantations seems a key factor that could increase the occurrence of native fauna in plantations. We found that stands of Monterery pine with no or barely developed understory contained fewer species of medium‐sized mammals, which is consistent with Nájera and Simonetti's () finding that Guatemalan oil palm plantations with little understory support fewer bird species than stands with a well‐developed understory. That the experimental removal of understory reduced the use of such stands by mammals strongly suggests understory enhances the quality of plantations as habitat for native fauna, which in this case includes 2 vulnerable species, kodkod and Southern pudu.…”

Conservation opportunities in commercial plantations: The case of mammals

“…Although it has been recognised that the maintenance of the understory vegetation can improve habitat quality within plantations by providing resources for mammals (Bellows et al 2001;Hartley 2002;Lindenmayer & Hobbs 2004), no experimental studies have addressed this issue at this time. Nájera and Simonetti (2010b) have demonstrated that the removal of the understory vegetation reduces bird diversity and abundance in oil palm plantations, but this kind of research is absent in the case of mammals.…”

Establishing the evidence base for maintaining biodiversity and ecosystem function in the oil palm landscapes of South East Asia

“…Understorey vegetation has been shown to be important in maintaining the abundance and richness of beetle assemblages in oil palm in Sabah [18] and of bird communities in Guatemalan oil palm [100]. Understorey vegetation can also be important in producing increased amounts of leaf litter in plantations, which can itself support a higher diversity and abundance of taxa [18].…”