Palm heart harvesting in the Brazilian Atlantic forest: changes in industry structure and the illegal trade

1. Until the late 1960s, Euterpe edulis was the most important edible palm species in the Brazilian markets. Since then, overharvesting of natural stands and the limited scope of plantations have caused the industry to shift to the multistemmed E. oleracea from the Amazon river estuary.
2. As a result of the relocation of the industry, the structure of the palm harvesting industry has changed and illegal trade has continued to exploit the remaining natural stands of E. edulis .
3. It is suggested that, to avoid the total harvesting of E. edulis and to achieve sustainable management of the palm heart, it will be necessary to diversify the local economy, create incentives for small land owners to improve their management practices, while keeping their competitiveness against the illegal trade, create the incentive of new sources of palm hearts and create a 'green stamping' for management palms.
4. Transformation of the illegal structure of the palm heart industry is probably the only solution to avoid the total depletion of the wild stands of E. edulis .     

Fruit Availability and Peccary Frugivory in an Isolated Atlantic Forest Fragment: Effects on Peccary Ranging Behavior and Habitat Use

The goal of this study was to examine seasonal frugivory by two sympatric peccary species ( Tayassu pecari and T. tajacu ) in a small (2178 ha), Atlantic Forest fragment on the inland plateau region of São Paulo State, Brazil. Fruit availability was determined with systematic ground surveys conducted over a 5-yr period. Examining fruit availability trends for dry and wet seasons, we found that species diversity was greater in the wet season, but the total number and dry mass of fruits were higher in the dry season. Fruit abundance in the dry season was due to one palm, 'jeriva' ( Syagrus romanzoffiana ), which could be considered a keystone species at Caetetus Ecological Station as it also supported a diverse array of mammals, birds, reptiles, and insects. White-lipped peccaries were the only ungulates that ate palmito fruits ( Euterpe edulis ) at Caetetus. They consumed ripe and unripe fruits and predated the seeds by chewing the pulp and seed. This occurred primarily during the dry season and was associated with a seasonal range shift and a preference for palmito habitat by the white-lipped peccaries. The dominance of fruits in peccary diets (80% fruit items in scat) has management implications for other plateau forest fragments. Forest fragments with diminished fruit abundance or diversity, or lacking key species such as S. romanzoffiana or E. edulis , will not support the energetic requirements of the characteristically large and highly mobile white-lipped peccary populations.     

Exploiting fruits of a threatened palm to trigger restoration of Brazil's Atlantic Forest

Recent global commitments to forest and landscape restoration in the tropics call for new management approaches that benefit both biodiversity and livelihoods of forest‐dependent people. The sustainable use of wild forest products is a promising pathway, but requires clarity about harvested species' demography and harvesters' rights. Here, we explored how the exploitation of fruits of the threatened palm Euterpe edulis, a key fruit source for wildlife in Brazil's globally important Atlantic Forest biodiversity hotspot, could trigger local community involvement in restoration. This palm has both non‐destructive (fruit) and destructive (palm heart) culinary uses, each with unique biological and resource‐use conditions. We quantified all demographic stages of this species in multiple agroforests, secondary forests, and protected areas to parameterize demographic projections of palm populations, harvest profitability, and fruit provisioning to wildlife under different management scenarios. Field observations showed a clear depression of adult palm populations in protected areas, likely due to palm heart poaching, and of intermediate size classes in agroforests, probably from weeding by farmers. Field data and demographic models reveal that in this region, agroforests and secondary forests can successfully conserve this species while providing lasting profits for farmers under most scenarios. These findings demonstrate a clear case where local stakeholders both contribute to and benefit from restoration through harvest of wild products and also highlight a potential source of income from regenerating tropical forests.     

Genetic structure, mating system, and long-distance gene flow in heart of palm (Euterpe edulis Mart.)

We report a detailed analysis of the population genetic structure, mating system, and gene flow of heart of palm (Euterpe edulis Mart.-Arecaceae) in central Brazil. This palm is considered a keystone species because it supplies fruits for birds and rodents all year and is intensively harvested for culinary purposes. Two populations of this palm tree were examined, using 18 microsatellite loci. The species displays a predominantly outcrossed mating system (tm = 0.94), with a probability of full sibship greater than 70% within open-pollinated families. The following estimates of interpopulation genetic variation were calculated and found significant: FIT = 0.17, FIS = 0.12, FST = 0.06, and RST = 0.07. This low but significant level of interpopulation genetic variation indicates high levels of gene flow. Two adult trees were identified as likely seed parents (P > 99.9%) of juveniles located at a distance of 22 km. Gene flow over such distances has not been reported before for tropical tree species. The establishment and management of in situ genetic reserves or ex situ conservation and breeding populations for E. edulis should contemplate the collection of several hundreds open-pollinated maternal families from relatively few distant populations to maximize the genetic sampling of a larger number of pollen parents.     

Palm Harvest Impacts in North-Western South America

Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants in tropical American forests. This paper introduces a cross-disciplinary study of the effects of harvesting palm products from the tropical forests in north-western South America. The size of the resource is estimated through palm community studies in the different forest formations that determines the number of species and individuals of all palm species. The genetic structure of useful palm species is studied to determine how much harvesting of the species contributes to genetic erosion of its populations, and whether extraction can be made without harm. Almost all palm species are used in rural communities for subsistence purposes Quantitative ethno-botanical research in different forest types have identified thousands of different ways of using palms for food, construction, tool-making, etc. Although most palms are used by the person harvesting them, many are sold on local markets as fruits, fiber, tools, construction materials etc., and a few have reached larger markets, including international markets. Palm populations are managed in various ways of which some are sustainable and others are destructive. National level mechanisms that governs extraction, trade and commercialization of palm products, are used to identify positive and negative policies in relation to resilience of ecosystems.     

Fruiting phenology of palms and trees in an Atlantic rainforest land-bridge island

Tropical forests show periods of scarcity and high fruit production in the same year and/or between years. Palms are an important component of Neotropical rainforests and a significant food resource for several frugivores. Therefore, their role as keystone resource may be exacerbated in highly impoverished areas. In Anchieta Island, São Paulo/Brazil, human settlements have modified and impoverished the forest, mainly through overharvesting and the introduction of exotic plants and several mammal species. We assessed the offer of fruits consumed by vertebrate frugivores at this island, the vegetation of which is belonging to the Brazilian Atlantic rainforest. We compared whether the fruiting patterns and fruit fall differ between palms and trees, and discuss the importance of palms as a food resource for frugivores and the implications for Anchieta Island conservation. Phenological patterns were seasonal for both trees and palms; however, the times of fruiting occurrence differed. Fruit fall biomass was at least twice lower than reported for other Atlantic rain forests and was also different between trees and palms. Palms contributed more than 80% of the overall fruit fall biomass. Palms may constitute an alternative food resource in periods of low fruit availability, although they do not provide resources for the entire assemblage of vertebrate frugivores. Energy-rich fruits, such as those produced by palms, may play an important role in the maintenance of frugivore populations in isolated, disturbed environments with a high density of vertebrate frugivores, low diversity of fruiting species and fruit biomass such as those found on Anchieta Island.     

Disruption of recruitment in two endemic palms on Lord Howe Island by invasive rats

Invasive species may have negative impacts on many narrow range endemics and species restricted to oceanic islands. Predicting recent impacts of invasive species on long-lived trees is difficult because the presence of adult plants may mask population changes. We examined the impact of introduced black rats (Rattus rattus) on two palm species restricted to cloud forests and endemic to Lord Howe Island, a small oceanic island in the southern Pacific. We combined estimates of the standing size distribution of these palms with the proximal impacts of rats on fruit survival in areas baited to control rats and in unbaited areas. The size distribution of palms with trunks was comparable across baited and unbaited sites. Small juvenile palms lacking a trunk (<50 cm tall) were abundant in baited areas, but rare in unbaited sites for Lepidorrhachis mooreana, and rare or absent in 3 out of 4 unbaited Hedyscepe canterburyana sites. All ripe fruits were lost to rats in the small fruited L. mooreana. Fruit removal was widespread but less (20–54%) in H. canterburyana. Both palms showed evidence of a reduced capacity to maintain a juvenile bank of palms through regular recruitment as a consequence of over 90 years of rat impact. This will limit the ability of these species to take advantage of episodic canopy gaps. Baiting for rat control reduced fruit losses and resulted in the re-establishment of a juvenile palm bank. Conservation of both endemic palms necessitates control (or eradication) of rat populations on the unique cloud forest summits of the island.     

Edge effects on palm diversity in rain forest fragments in western Ecuador

At the edges of tropical rain forest fragments, altered abiotic and biotic conditions influence the structure and dynamics of plant communities. In Neotropical rain forests, palms (Arecaceae) are important floristic and ecological elements. Palms’ responses to edge effects appear to be idiosyncratic and to depend on the level of disturbance at edges. This paper explores how variation in forest structure at the edges of two old-growth forest fragments in a tropical rain forest in western Ecuador affects palms of different species, life-forms, and size classes. We investigate (1) how edge effects influence the relative proportion of palm adults and juveniles, (2) how distance from the forest edge affects palm density and species richness, (3) how altered forest structure along edges affects palm density. We found that at edges (1) palm communities had a lower proportion of adults relative to juvenile individuals compared to continuous forests, (2) the density of two species of palms and the overall species richness of the palm community tended to decrease toward the edges within forest fragments, and, (3) altered forest structure decreased the density of adult palms. Hence, edge effects on palms were controlled by the degree of modification of the forest structure, and by species responses to edge-related disturbance.     

Prospects for conserving biodiversity in Amazonian extractive reserves

Non‐timber forest product (NTFP) extraction is a popular alternative to timber extraction that figures prominently in efforts to utilize tropical forests sustainably. But the ability to conserve biodiversity through NTFP management, particularly in extractive reserves in Amazonia, has remained untested. We found that intensive management of Euterpe oleracea (Palmae) fruit, one of the most important extractive products in the Amazon, has substantial impacts on biodiversity, whereas moderate management does not. We mimicked traditional levels of fruit harvest in a replicated experiment over one fruiting season. High‐intensity harvest (75% of fruits removed) reduced avian frugivore species diversity by 22%. Low‐intensity harvest (40% of fruits removed), however, had no effect on diversity. On a larger scale, we found that forests with enriched densities of E. oleracea supported more fruit‐eating birds but fewer non fruit‐eating birds than non‐enriched forests. Taken together, these results suggest that intensive NTFP management to meet market demands may trigger substantial ecological impacts, at least at the level of our study. E. oleracea harvest should be limited where conservation of biodiversity is a goal.     

Landscape‐scale deforestation decreases gene flow distance of a keystone tropical palm,Euterpe edulis Mart (Arecaceae)

Habitat loss represents one of the main threats to tropical forests, which have reached extremely high rates of species extinction. Forest loss negatively impacts biodiversity, affecting ecological (e.g., seed dispersal) and genetic (e.g., genetic diversity and structure) processes. Therefore, understanding how deforestation influences genetic resources is strategic for conservation. Our aim was to empirically evaluate the effects of landscape‐scale forest reduction on the spatial genetic structure and gene flow of Euterpe edulis Mart (Arecaceae), a palm tree considered a keystone resource for many vertebrate species. This study was carried out in nine forest remnants in the Atlantic Forest, northeastern Brazil, located in landscapes within a gradient of forest cover (19–83%). We collected leaves of 246 adults and 271 seedlings and performed genotyping using microsatellite markers. Our results showed that the palm populations had low spatial genetic structure, indicating that forest reduction did not influence this genetic parameter for neither seedlings nor adults. However, forest loss decreased the gene flow distance, which may negatively affect the genetic diversity of future generations by increasing the risk of local extinction of this keystone palm. For efficient strategies of genetic variability conservation and maintenance of gene flow in E. edulis, we recommend the maintenance of landscapes with intermediary to high levels of forest cover, that is, forest cover above 40%.     

Microhabitat specialization in a species-rich palm community in Amazonian Ecuador

1 Relationships between microhabitat variables (altitude, inclination, topographic position, drainage, canopy height) and the distribution and abundance of palms and palm-like plants in 50 ha of old-growth terra firme rain forest in the Yasuní National Park, lowland Amazonian Ecuador, were examined using 118 20 × 20 m plots laid out in a stratified random design.
2 If microhabitat niche differentiation is important for maintaining the species richness of the community, then (i) the distribution of the palms will be strongly influenced by microhabitat heterogeneity and (ii) palms of similar growth form will show antagonistic microhabitat relationships.
3 Mantel and cluster analyses showed that palm species distributions were strongly structured by topography. The main difference in species composition was between plots in the bottomland and plots on the upper slopes and hill tops.
4 Logistic and logit analyses showed that 20 of the 31 palm and palm-like taxa analysed had distributions that were significantly related to the microhabitat variables measured, mainly to topography but also to drainage and canopy height.
5 Spatial autocorrelation in the overall community structure was not explained by the microhabitat variables. Analyses of distributions or abundances of single species showed neighbourhood effects for seven taxa.
6 Antagonistic patterns of microhabitat preferences were recognizable among some species pairs of small palms, medium-sized palms and palm-like plants, but not among canopy palms.
7 It is concluded that microhabitat specialization is an important factor in maintaining the diversity of this palm community, while mass effects might also be important.     

Fruit patch size and frugivory in the lowland tapir (Tapirus terrestris)

Large non-ruminant ungulates consume the more abundant low-quality forage because this gives them the advantage of reducing search effort. However, large-bodied herbivores would be predicted to search for high-quality fruit patches if these patches were of large size and the fruits rich in nutrients. Diets of lowland tapir ( Tapirus terrestris ), a large non-ruminant of the Amazon basin, were examined from animals of north-eastern Peru to investigate this relationship between high-quality fruit, lower-quality browse and searching behaviour. Lowland tapir consumed on average 33% fruit, which is relatively high for a large non-ruminant ungulate. The fruit portion of lowland tapir diets was dominated by the nutritious Mauritia flexuosa (Palmae) drupes, which were selected by tapir more frequently than other fruit types. M. flexuosa palms grow in virtually monotypic stands and occur in larger patches than other fruit trees used by terrestrial herbivores of the Amazon. Lowland tapir encountered fruits more frequently when ranging in M. flexuosa palm forests than in non-palm forests, because they changed their searching behaviour once they entered palm forests by turning more abruptly. It appears that lowland tapir can consume greater proportions of fruit than other large non-ruminant ungulates, because they exploit a nutritious fruit that occurs in large patches and that meets the energy demands of their large body size.     

Genetic differentiation of Euterpe edulis Mart. populations estimated by AFLP analysis

Heart-of-palm (Euterpe edulis Mart.) is a wild palm with a wide distribution throughout the Atlantic Rainforest. Populations of E. edulis represent important renewable natural resources but are currently under threat from predatory exploitation. Furthermore, because the species is indigenous to the Atlantic Rainforest, which is located in the most economically developed and populated region of Brazil, social and economic pressures have devastated heart-of-palm forests. In order to estimate the partitioning of genetic variation of endangered E. edulis populations, 429 AFLP markers were used to analyse 150 plants representing 11 populations of the species distribution range. Analysis of the genetic structure of populations carried out using analysis of molecular variance (AMOVA) revealed moderate genetic variation within populations (57. 4%). Genetic differentiation between populations (FST = 0.426) was positively correlated with geographical distance. These results could be explained by the historical fragmentation of the Atlantic coastal region, together with the life cycle and mating system. The data obtained in this work should have important implications for conservation and future breeding programmes of E. edulis.     

Degraded lands worth protecting: the biological importance of Southeast Asia's repeatedly logged forests

Southeast Asia is a hotspot of imperilled biodiversity, owing to extensive logging and forest conversion to oil palm agriculture. The degraded forests that remain after multiple rounds of intensive logging are often assumed to be of little conservation value; consequently, there has been no concerted effort to prevent them from being converted to oil palm. However, no study has quantified the biodiversity of repeatedly logged forests. We compare the species richness and composition of birds and dung beetles within unlogged (primary), once-logged and twice-logged forests in Sabah, Borneo. Logging had little effect on the overall richness of birds. Dung beetle richness declined following once-logging but did not decline further after twice-logging. The species composition of bird and dung beetle communities was altered, particularly after the second logging rotation, but globally imperilled bird species (IUCN Red List) did not decline further after twice-logging. Remarkably, over 75 per cent of bird and dung beetle species found in unlogged forest persisted within twice-logged forest. Although twice-logged forests have less biological value than primary and once-logged forests, they clearly provide important habitat for numerous bird and dung beetle species. Preventing these degraded forests from being converted to oil palm should be a priority of policy-makers and conservationists.     

Demography of Euterpe precatoria and Mauritia flexuosa in the Amazon: application of integral projection models for their harvest

Non‐Timber Forest Products like palm fruits are fundamental in the livelihood of Amerindian groups. For the last 10 years the fruits of wild palm species, like Euterpe precatoria and Mauritia flexuosa, have been entering into global markets. These species are mostly harvested felling the adults, a practice that may have a disproportionate impact in the conservation of the populations. We studied the demography of E. precatoria and M. flexuosa, two important palms of the Amazon, using integral projection models, to characterize the population dynamics and project impact of different fruit harvest methods: adult felling and direct fruit harvest. We followed over 1400 individuals from populations with low harvest intensities in the Tikuna community of Amacayacu, Amazonas, Colombia from 2011 to 2013, establishing four plots for E. precatoria in seasonally inundated forests and two for M. flexuosa in swamps. The population growth in E. precatoria was slightly declining, whereas M. flexuosa was stable. As expected, the simulations of adult felling diminished λ and the number of available adults under any scenario for either species. On the contrary, the simulations support existing information that climbing and other non‐destructive harvest methods would probably allow a sustainable management, satisfying the demand and preserving wild populations.     

How human disturbance of tropical rainforest can influence avian fruit removal

Fruit consumption by birds is an important ecological interaction that contributes to seed dispersal in tropical rainforests. In this field experiment, we asked whether moderate human disturbance alters patterns of avian frugivory: we measured fruit removal by birds in the lower montane rainforest of Tobago, West Indies, using artificial infructescences made with natural fruits from two common woody plants of the forest understory (Psychotria spp., Rubiaceae). Displays were mounted simultaneously in three forest habitats chosen to represent a gradient of increasing habitat disturbance (primary, intermediate and disturbed), caused by subsistence land use adjacent to a protected forest reserve. We measured the numbers of fruits removed and the effect of fruit position on the likelihood of removal, along with the abundances of all fruits and fruit‐eating birds at the study sites. Fruit removal was highly variable and there was not a significant difference in removal rate among forest habitats; however, the trend was for higher rates of removal from displays in primary forest. Canopy cover, natural fruit availability, and frugivore abundance were not good predictors of fruit removal. Birds preferred more accessible fruits (those proximal to the perch) in all habitats, but in disturbed forest, there was a tendency for distal fruits to be chosen more frequently than in the other forest types. One possible explanation for this pattern is that birds in disturbed forests were larger than those in other habitats, and hence were better able to reach the distal fruits. Coupled with differences in bird community composition among the forest types, this suggests that different suites of birds were removing fruit in primary versus disturbed forest. As frugivore species have different effectiveness as seed dispersers, the among‐habitat differences in fruit removal patterns that we observed could have important implications for plant species experiencing disturbance; these possible implications include altered amounts of seed deposition and seedling recruitment in Tobago's tropical rainforest.     

Damage and Recovery of Riparian Sierra Palms after Hurricane Georges: Influence of Topography and Biotic Characteristics

Tropical forests are often shaped by disturbance events, especially in regions where hurricanes and other severe storms occur. We studied the effects of Hurricane Georges (September 1998) on the sierra palm ( Prestoea acuminata var. montana ) in the Luquillo Mountains of Puerto Rico. We established riparian transects along two headwater streams that were similar in size and location, but differed in riparian tree species composition and land-use history. Following Hurricane Georges, sierra palms were surveyed periodically for damage and recovery (measured by initial loss and subsequent regrowth of palm leaves), tree height, sun exposure, and production of inflorescences and infructescences. Palm height had the highest association with damage, with most damage occurring to canopy palms. Palm recovery (4 mo and 10 mo post-hurricane) was associated with high tree density, indicating that sun exposure was not limiting. Hurricane Georges likely reduced production of flowers and fruits in sierra palms for at least 10 mo following the storm, although production of new leaves was rapid. Although palms recovered quickly from defoliation after the hurricane, decreased reproduction resulted in reduced availability of fruit for terrestrial and aquatic consumers.     

Determinants of fruit removal in <Emphasis Type="Italic">Geonoma pauciflora</Emphasis>, an understory palm of neotropical forests

Competition for seed dispersers is supposedly a selective force that drives the evolution of plant reproductive traits. In the understory of tropical forests, such competition should be especially severe among bird-dispersed plant species because (i) the production of copious fruit crops is limited by low light availability; (ii) there usually is a high density of fleshy fruited plants, and (iii) understory frugivorous birds are not abundant. In this paper, we took advantage of a high-density population of Geonoma pauciflora, a bird-dispersed palm species growing in the understory of the Brazilian Atlantic forest, to investigate the influence of plant traits and its immediate neighborhood on fruit removal. Intrinsic (crop and fruit sizes) and extrinsic traits (related to light availability) affected the fruit removal of G. pauciflora. Crop size had a greater influence than fruit size on the absolute number of fruits removed, whereas none of the investigated traits influenced decisively fruit removal efficiency (i.e., the proportion of an individual’s crop removed). The influence of light availability was mostly indirect, through its positive influence on fruit production. A significant positive spatial autocorrelation in removal efficiency occurred among neighboring plants within a 7-m radius, which is indicative of facilitation among neighboring individuals. The consequence of such positive spatial autocorrelation in removal efficiency for clonal plants such as G. pauciflora is that by attracting a frugivore a given ramet may promote the removal of fruits of other ramets, thus enhancing the reproductive output of the genet as a whole.     

Chorology of New Caledonian palms and possible evidence of Pleistocene rain forest refugia.

The distribution of the 36 palm species of New Caledonia is studied in relation to several parameters: elevation, rainfall, geological substrate, phytogeographical sectors and vegetation types. The climate (thermal gradient and rainfall) appears to be the principal factor influencing the distribution of palms, the substrate effect being subordinate to the climatic pattern. Nearly all palm populations are included within the 1,500 mm isoline. Maximum levels of species richness and endemism are located in four areas receiving more than 3,000 mm of annual rainfall. We interpret these areas as former Pleistocene refugia of lowland rain forest based on three lines of evidence: 1) all locally endemic lowland palm species and genera are restricted to these areas; 2) local endemics occur on east-facing slopes receiving the highest rainfall and most likely to have sustained rain forests during the driest periods; and 3) several pairs of sister species are disjunct between the southeastern and northeastern high rainfall areas.     

Effects of frugivore impoverishment and seed predators on the recruitment of a keystone palm

Many plant species are threatened as a result of extinction of their large-bodied frugivores all over the world. Additionally, introduced herbivores and seed predators may cause severe pressure on early stages of plant recruitment. We studied the seed dispersal and seed predation of the keystone palm Euterpe edulis on a land-bridge island with a highly impoverished frugivore fauna and overabundant seed predators, and in a continuous Atlantic forest in Brazil. While the diversity of avian seed dispersers and predators was higher on the mainland, the abundance of seed dispersers was 4-fold higher on the island. Turdus flavipes was responsible for 72% and 96% of seeds removed in the island and mainland, respectively. However, the higher density of T. flaviceps on the island did not result in higher seed removal. In fact, seed removal rate was 1.7 times lower there than on the mainland, probably due to the aggressive behavior of the major seed disperser who defend palm fruits. Seed predation, on the other hand, was markedly higher on the island, where nearly 100% of seeds were preyed upon, but only 0.3% on the mainland. As a consequence of higher seed predation the population of E. edulis has few numbers of seedlings and saplings on the island. Therefore, management of the seed predator populations on the island is a key priority for recovering the natural population of this keystone palm and the frugivores that depend on its fruits.