Jacques H. C. Delabie

Landscape and farm scale management to enhance biodiversity conservation in the cocoa producing region of southern Bahia, Brazil

In southern Bahia, Brazil, large land areas are used for the production of cocoa (Theobroma cacao), which is predominantly grown under the shade of native trees in an agroforestry system locally known as cabruca. As a dominant forest-like landscape element of the cocoa region, the cabrucas play an important role in the conservation of the region’s biodiversity. The purpose of this review is to provide the scientific basis for an action plan to reconcile cocoa production and biodiversity conservation in southern Bahia. The available research collectively highlights the diversity of responses of different species and biological groups to both the habitat quality of the cabrucas themselves and to the general characteristics of the landscape, such as the relative extent and spatial configuration of different vegetation types within the landscape mosaic. We identify factors that influence directly or indirectly the occurrence of native species in the cabrucas and the wider landscape of the cocoa region and develop recommendations for their conservation management. We show that the current scientific knowledge already provides a good basis for a biodiversity friendly management of the cocoa region of southern Bahia, although more work is needed to refine some management recommendations, especially on shade canopy composition and density, and verify their economic viability. The implementation of our recommendations should be accompanied by appropriate biological and socioeconomic monitoring and the findings should inform a broad program of adaptive management of the cabrucas and the wider cocoa landscape.

Contribution of cocoa plantations to the conservation of native ants (Insecta: Hymenoptera: Formicidae) with a special emphasis on the Atlantic Forest fauna of southern Bahia, Brazil

By maintaining a forest-like structure, shaded cocoa plantations contribute to the conservation of ants that usually live in the soil, leaf litter or canopy of tropical forests. Here we synthesize the available information on the diversity and community structure of ants in shaded cocoa plantations in the Atlantic forest region of Brazil, compare ant assemblages in cocoa agroforests with forests and other forms of agriculture, and discuss how these shaded plantations contribute to the conservation of the ants in the Atlantic Forest region. We also discuss ants of economical importance and of special interest, including Camponotus, Dolichoderus, Gnamptogenys, Pachycondyla, Pseudomyrmex and other litter dwelling genera. We discuss the situation of the tramp ant Wasmannia auropunctata in the Bahian cocoa-producing region where it is considered as native, and that of the two cryptobiotic genera Thaumatomyrmex and Typhlomyrmex, as well as that of proven and possible endangered army ant and Ponerini species. A total of 192 ant species from four strata were found in extensive sampling of a cocoa plantation with a relatively simple shade canopy (comprised primarily of Erythrina). Species richness in the cocoa plantations corresponded roughly to that of low diversity native forests, and species composition of cocoa plantations was most similar to native habitats (forest and mangroves) while ant composition in other agricultural habitats was most similar to that of urban areas. Although occurrences of Wasmannia auropunctata were similar in cocoa plantations and forests, abundance of Thaumatomyrmex and Typhlomyrmex, generally thought to be rare ants, was relatively high in cocoa plantations. These results, from cocoa plantations with relatively simple shade, demonstrate the importance of cocoa for ant conservation in the Atlantic forest region of Brazil. It is likely that cocoa plantations with a greater number of vegetation strata and higher tree species richness (such as traditional cabruca plantations) provide even more important habitat for ants generally and for ant species of conservation concern.

Conservation in tropical landscape mosaics: the case of the cacao landscape of southern Bahia, Brazil

A recent debate has contrasted two conservation strategies in agricultural landscapes; either “land sparing” farm development combining intensive production practices with forest set-asides, or “wildlife-friendly” farming with greater on-farm habitat value but lower yields. We argue that in established mosaic landscapes including old cacao production regions where natural forest has already been reduced to relatively small fragments, a combination of both strategies is needed to conserve biodiversity. After reviewing the evidence for the insufficiency of either strategy alone if applied to such landscapes, the paper focuses on the cacao production landscape of southern Bahia, Brazil, once the world’s second largest cacao producer. Here, small remaining areas of Atlantic Forest are embedded in a matrix dominated by traditional cacao agroforests, resulting in a landscape mosaic that has proven favorable to the conservation of the region’s high biodiversity. We show that current land use dynamics and public policies pose threats but also offer opportunities to conservation and describe a three-pronged landscape conservation strategy, consisting of (i) expansion of the protected areas system, (ii) promotion of productive yet biodiversity-friendly cacao farming practices, and (iii) assistance to land users to implement legally mandated on-farm reserves and voluntary private reserves. We discuss recent experiences concerning the implementation of this strategy, discuss likely future scenarios, and reflect on the applicability of the Bahian experience to biodiversity rich cacao production regions elsewhere in the tropics.

Diversidade de formigas (Hymenoptera: Formicidae) da serapilheira em eucaliptais (Myrtaceae) e área de cerrado de Minas Gerais

The inventory of the ant fauna in a cerrado area and in eucalypt plantations with five classes of understory ages, has been carried out in Bom Despacho (MG), in the aim to evaluate the effect of plantation age on the diversity of native cerrado ants. Fifteen areas of eucalypt have been sampled, being three per age class, as follows: areas with understory of 0 to 2, 2 to 4, 4 to 6, 6 to 8 and 8 to 10 years old, respectively). The same has been made in a native vegetation area used as control . The ants from the litter have been extracted using Winkler sacks. One hundred and forty three ant species have been collected, belonging to six subfamilies, being 67 in the native area (50 samples) and 133 in the eucalypt plantations (750 samples, corresponding to an average of 52 species per group of 50 samples, or sampled area). With the Chao 2 diversity estimator index, there is no significant differences between areas (Kruskal-Wallis, P>0.05). It has been demonstrated that most of the species found in native vegetation occur also in the eucalypt plantations, although these ones present a drastic diminution of the species density, suggesting that the ant regional richness do not depend on the complexity of the habitat, because the cerrado ant fauna is well conserved in the eucalypt plantations, contradicting most of the literature on this subject.

As formigas como indicadores biológicos do impacto humano em manguezais da costa sudeste da Bahia

Mangroves are common in estuaries along the Atlantic coast of Brazil. Although plant diversity is low, this ecosystem supports a range of animals, offering some resources for non-aquatic organisms. Many insects live in mangroves and, between them, many ant species that are exclusively arboreous. Mangroves throughout the world suffer from high levels of human impact, and this is particularly true for southeastern Bahia, where land-uses include traditional crab and fish exploitation, urban development, refuse pollution, recreation, and timber extraction. The ants of 13 mangrove sites, representing a range of levels of human use, have been studied along 250 km of the southern Bahia littoral, between Itacaré and Porto Seguro. Ants were sampled both inside and on the periphery of the tidal zone, using entomological rainbow, baiting, collect of hollow branches and pit-fall. A total of 108 species have been collected, with the richest genera being Camponotus and Pseudomyrmex, and the most frequent belonging to the genera Azteca and Crematogaster. The ant community living on the periphery of mangrove areas is rather homogeneous regardless of the degree of environmental perturbation, but varies markedly with the disturbance inside the mangroves themselves. The evolution of richness of the both communities, mangrove and periphery, is negatively related to the human effects, even limited to the periphery. Ant communities therefore have the potential to be useful as biological indicators of ecological impacts of land-use in these mangrove systems.

Impacto de iscas formicidas granuladas sobre a mirmecofauna não-alvo em eucaliptais segundo duas formas de aplicacação

The effect of localized and systematic use of granulated bait for cutting ant control was assessed on a community of non-target ants in eucalyptus in the municipality of Bom Despacho, Minas Gerais State, Brazil. The ants were collected in Winkler traps on three occasions: eight days before bait distribution, eight and sixty days after distribution by removing the mirmecofauna from 50 1-m2 samples of litter. A total of 102 species was collected belonging to six sub-families. The seven most frequent ant species were analyzed in more detail to assess more precisely the consequences of insecticide treatments. The study showed that systematic control caused negative and more prolonged impact on the ant community than localized control.

Avaliação rápida da diversidade de formigas em sistemas de uso do solo no sul da Bahia

We aimed to compare the soil ant diversity in different land use systems from Atlantic Forest area, in Southern Bahia state, Brazil. The ants were sampled in 16 sites: two primary forest sites (un-logged forest); three young secondary forests (<8 years old); three intermediate secondary forests (8-20 years old); three old secondary forests (>20 years old); three Eucalyptus grandis plantations (3-7 years old), and two introduced pastures. Each site was sampled in three sampling points 15 m apart, and distant over 50 m from the site edge. In each sampling point we gathered the litter from a 1 m² and extracted the ants with Winkler extractors during 48h. We found 103 ant species from 29 genera and eight subfamilies. The five richest genera were Pheidole (19 species), Solenopsis (8), Apterostigma (10), Hypoponera (7) e Paratrechina (5). The highest ant richness density was found in the primary forest (7.4 species/sample; S = 37; n = 5); followed by the old secondary forest (5.33 species/sample; S = 48; n = 9); young secondary forest (5.25 species/sample; S = 42, n = 8); eucalyptus plantation (4.22 species/sample; S = 38, n = 9), intermediate secondary forest (3.5 species/sample; S = 35, n = 10, and introduced pasture (2.67 species/sample; S = 16, n = 6). The ecosystems with higher structural complexity showed the highest ant richness density by sample. Therefore, in the Atlantic Forest region, the eucalyptus plantation is a better alternative of land use to conserve the ant biodiversity than pastures, and quite similar to native secondary forests in ant community characteristics.

Check list of ground-dwelling ants (Hymenoptera: Formicidae) of the eastern Acre, Amazon, Brazil

The ant fauna of state of Acre, Brazilian Amazon, is poorly known. The aim of this study was to compile the species sampled in different areas in the State of Acre. An inventory was carried out in pristine forest in the municipality of Xapuri. This list was complemented with the information of a previous inventory carried out in a forest fragment in the municipality of Senador Guiomard and with a list of species deposited at the Entomological Collection of National Institute of Amazonian Research– INPA. The resulting list covered 268 species distributed in 52 genera and nine subfamilies, and records 23 species and four morphospecies for the first time in the state of Acre. Due to the large environmental heterogeneity, future inventories will be crucial to properly describe and understand ant species distribution patterns in southwestern Amazon.

Interação de fragmentos florestais com agroecossistemas adjacentes de café e pastagem: respostas das comunidades de formigas (Hymenoptera, Formicidae)

The responses of the ant community to environmental change, from forest fragment to agroecosystems (coffee or pasture) were evaluated in the south of the state of Minas Gerais, Brazil. In this paper we analized the interactions between forest and the two most typical agroecosystem from southest Brazil: sun-growing coffee plantation and introduced pasture. We sampled the ant community from five of each agroecosystems, inside the adjacent forest fragment, and on the edge between them. In each site we removed the litter from fifteen 1m2 plots and extracted the ants using a Winkler extractor. A total of 165 ant species, distributed in 48 genera and 10 subfamilies were recorded. The coffee plantation presented the lowest abundance and estimated species richness. The causes of the changes observed among the areas are discussed.

Impacto das capinas mecânica e química do sub-bosque de Eucalyptus grandis sobre a comunidade de formigas (Hymenoptera: Formicidae)

O efeito das capinas mecânica e quimica do sub-bosque em plantacoes de eucaliptos e as consequencias desses tratamentos sobre a comunidade de formigas foram avaliados no municipio de Bom Despacho, Minas Gerais, Brasil. As formigas foram coletadas com o extrator de Winkler. Coletou-se um total de 86 especies, pertencentes a seis subfamilias. Oito dias apos as capinas, o numero de especies reduziu-se de um quarto para os dois tipos de capina. Sessenta dias apos, o numero de especies tendeu a retornar ao estagio inicial, verificando-se que a eliminacao do sub-bosque causa efeito deleterio imediato, de igual intensidade e de pouca duracao sobre a comunidade de formigas. As razoes das variacoes observadas serao discutidas.