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Forest dynamics papers presented at conservation conference in Brazil Annual Meeting of the Society for Conservation Biology July 27, 2005 Below is a sampling of some forest dynamics papers submitted for the conference. All descriptions are excepts from the official "Book of Abstracts" from the meeting. More abstracts. VULINEC, KEVINA; Lima, Albertina Pimentel. Department of Agriculture and Natural Re-XIX Annual Meeting of the Society for Conservation Biology ABSTRACTS sources, Delaware State University, Dover, Delaware USA (kvulinec((AT)) desu.edu); Instituto Nacional de Pesquisas da Amazônia, Departamento de Ecologia, Manaus, AM, Brasil (APL). Dung beetles are often considered to have positive effects on seeds defecated by frugivores in tropical forests. In research that spanned several divergent locations and habitat types across the Amazon, we surveyed beetle communities through baited pitfall trap transects. We determined that dung beetle community structure varied substantially and resulted in dominance by different species at each locality. Large nocturnal tunnelers (Dichotomius spp.) dominated terra firme forest, medium-sized diurnal and nocturnal rollers (Canthon fulgidus and C. aequinoctialis) dominated varzea sites, and dry tropical forest fragments were dominated by one medium-sized tunneler (Dichotomius lucasi). Additionally, we measured seed burial and movement patterns at three locations. The pattern of bead movement and burial differed radically across locations, indicating that seeds may be both positively and negatively impacted by the activity of dung beetles. Forest disturbance generally has a detrimental effect on beetle communities, although secondary forest in most areas contains a high biomass of large nocturnal tunneling beetles that bury large seeds effectively. Because secondary forests often harbor as many frugivorous primates as primary forests, these habitats may become critical refugia for important suites of seed dispersers and deserve protection for their potential to regenerate to primary forest VEGETATION STRUCTURE OF GALLERY FORESTS VERSUS BOSQUETS: CONSERVATION OF NATURAL FRAGMENTS AT LOPÉ NATIONAL PARK IN CENTRAL GABON. UKIZINTAMBARA, THARCISSE. Department of Environmental Studies Antioch New England Graduate School; Avon Street, Keene, New Hampshire 03431, USA. Studies have been conducted on human-induced fragmentation - one of the major causes of species decline in tropical forests. However, we know little on the extent of natural fragmentation and how they have sustained rare species that could have been lost due colonization by continuous forest. Between February 2001 and January 2003, we studied the natural fragmentation in the north of Lopé National Park. This landscape was created and maintained by periodic climate changes. We compared vegetation composition of isolated fragments (bosquets) with that of gallery forests. Both shared 39% of 251 species inventoried. Gallery forests contained 45% of species no encountered in bosquets while the later accounted for 16% of all species. Distance to gallery forests was a determinant factor of the differences in species diversity and composition within bosquets. The Shannon index H' was higher in bosquets closer to a gallery forests regardless of their sizes (ranging between 0.5 and 38ha). Larger bosquets were formed farther away from gallery forests and inaccessible by most seed dispersing animals. Seasonal fires have also been playing an important role in blocking the advancing continuous forest that could engulf forest fragments and eliminate this unique vegetation formation from the Lopé landscape RESTORATION OF THE PALO VERDE MARSH (COSTA RICA): RESPONSES OF PLANT COMMUNITIES TO Typha domingensis CONTROL. TRAMA, FLORENCIA; Rizo-Patrón, Federico; González, Eugenio. Programa Regional en Manejo de Vida Silvestre, Universidad Nacional. Apartado 1350- 3000. Heredia, Costa Rica, ftrama((AT))jabiru.ots.ac.cr(FT); Organización para Estudios Tropicales. De la UNED, Carretera a Sabanilla, 50 Este, 100 Sur. Ciudad de la Investigación UCR, último edificio, P.O Box 676-2050, San Pedro, Costa Rica (EG). Instituto Regional de Estudios en Sustancias Toxicas, Universidad Nacional, Apdo 86-3000. Heredia, Costa Rica (FRP). We assessed aquatic plant communities responses to restoration activities carried out at Palo Verde wetland (1207 ha), Costa Rica. By 1980 and due to changes in traditional management activities and hydrological alterations, this wetland was invaded by cattails (Typha domingensis). As a result, habitat quality decreased and fauna and flora diversity declined. In 2002 management activities started to reduce cattails by fangueo (crushing cattails under water with paddling wheels). From August 2003 to July 2004 we evaluated the response of aquatic plants to the restoration activities in three plots (80 ha each one), two under different restoration intensities and a control plot. Species richness and vegetation cover were measured using transects. We registered 61 plant species in treated plots and only 20 species in the control plot. The number of plant species was higher in plots under restoration than in the control plot (F=104; gl=2,195; P < 0.0001). Linear regression analysis showed a negative relationship between cattail cover and plant species richness (F=268.65; gl=1,112; r²=60.1; P < 0.0001). Plant species cover increased in plots with fangueo actions. Restoration activities have improved plant species habitat by decreasing cattails competition, and creating a habitat mosaic more suitable for waterbirds and other wildlife CREATION OF FOREST EDGES AND THE IMPOVERISHMENT OF FRAGMENTED LANDSCAPES IN THE BRAZILIAN ATLANTIC FOREST. SANTOS, BRÁULIO A.; Oliveira, Marcondes A.; Grillo, Alexandre S.; Tabarelli, Marcelo. Departamento de Botânica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Recife, PE, 50670-901, Brazil, santosba((AT))ufpe.br. Edge effects change both the taxonomic and ecological composition of tree species assemblages in tropical forest edges and small fragments. Recent reviews have suggested that these habitats tend to be converted into "secondary forests" in the long term. In order to test this hypothesis, we sampled tree species (DBH > 10 cm) in three habitats of a 3,500-ha fragment in the Brazilian Atlantic forest: (1) forest edges, i. e. 0-100 m distant from fragment border and not previously submitted to agriculture; (2) forest interior, i. e. patches of mature forests > 200 m distant from fragment border; and (3) 4-65-yr old patches of secondary forest, which were regenerating after slash-and-burn agriculture promoted in the center of the fragment. Simple linear regression models indicated that forest edges are similar to 30-40-yr old forests in terms of tree species density and richness, a half of the observed in the forest interior. Moreover, forest edges were similar to 15-28-yr old forests in terms of the percentage of emergent, shade-tolerant and large-seeded trees. Creation of edges promotes the establishment of low diversity "early secondary forests" and because of this highly fragmented landscapes in the Atlantic forest tend to retain impoverished and biased samples from the original flora ACCELERATING ECOSYSTEM RECOVERY AND RESTORATION IN DEGRADED LOWLAND FORESTS. Rolph, David; GRAY, ELIZABETH; Kollasch, Tom. The Nature Conservancy of Washington, 217 Pine Street, Suite 1100, Seattle, WA 98101, USA, egray((AT))tnc.org. Over the last century, low elevation temperate coniferous forests in the Pacific Northwest have been managed largely for commercial timber production, which has left a legacy of degraded habitat. It is widely recognized that restoration of these forests is critical. What is unknown is which restoration methods are most promising for accelerating ecosystem recovery and maximizing species diversity. To investigate this question, The Nature Conservancy recently acquired a 2,200 ha watershed on the Olympic peninsula of Washington state, USA. Because >95% of the watershed wasXIX Annual Meeting of the Society for Conservation Biology ABSTRACTS logged previously, our goal was to implement a long-term experimental study investigating how best to restore this landscape in a cost-effective manner. Success in designing and implementing an experimental approach to watershed-scale restoration has been challenging. We've found that to succeed in large scale experimental restoration, one must strive to not only restore habitat in a financially feasible manner, but to do it in a way that provides future restoration efforts with sound scientific milestones. Our findings suggest that this is best accomplished with an active adaptive management approach. In addition, projects will be most successful when resource management objectives are compatible between public and private landowners, and funding cycles encourage longterm experimentation and monitoring FRAGMENT SIZE AND EDGE EFFECTS ON LITTERFALL AND LITTER HUMIDITY IN ATLANTIC RAIN FOREST FRAGMENTS IN SOUTH-EAST BRAZIL. PORTELA, RITA DE C. Q.; Santos, Flavio A. M. Programa de Pós-Graduação em Ecologia, Departamento de Botânica, IB, UNICAMP, Campinas, SP, CP 6109,13.083-970, Brazil, rita((AT))quiteteportela.com.br. We assessed the litterfall, litter humidity, litter accumulation on the ground and canopy openness during 2001 and 2002 at the edge and interior of three small (14, 20, 29 ha) and one large (11,000 ha with three replicates) fragments of Atlantic Forest in São PauloABSTRACTS Universidade de Brasília, Brazil, July 2005 State. The litter production was bigger in the larger fragment, litter humidity and canopy openness did not vary with fragment size, and thickness of the litter layer was bigger in the smaller fragments. We can infer that the differences between litter fall and accumulation in the ground may be related with differences in the decomposition rate in these areas. Difference in the litter production and thickness of the litter layer was not found between fragments edges and interiors, litter humidity was bigger in the interior of the fragments, and the canopy of the forest was more opened in the edges. In the dry season there were an increase of litter production, a reduction of litter humidity and an increase of canopy openness, but did not have difference in the thickness of the litter layer FRAGMENT SIZE AFFECTS SEED DISPERSAL AND SEEDLING RECRUITMENT OF THE PALM Astrocaryum aculeatissimum IN THE BRAZILIAN ATLANTIC FOREST. PIRES, ALEXANDRA S.; Galetti, Mauro. Departamento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, 13507-700, Brazil, aspires((AT))biologia.ufrj.br (ASP, MG). Laboratório de Ecologia e Conservação de Populações, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil (ASP). Palms, an important food resource in tropical forests, are currently threatened by habitat loss, logging and defaunation. Seed fate was compared between two large (2400 and 3500ha) and three small (< 60ha) forest fragments. Endocarps within a 2m radius around stems were categorized as intact, predated by beetles or by rodents. In each fragment 20 experimental stations, with five threaded fruits each, were placed at 50m spacing. Experiments were checked 30 days latter and seeds categorized as intact, moved, buried or predated by rodents. In each area densities of seedlings, juveniles and adults were estimated in 0.5ha. The numbers of endocarps remaining below parent trees were significantly greater at small fragments, which had less seeds predated by rodents. In all fragments seeds not removed were heavily predated by beetles. The number of stations showing removal was significantly greater in larger fragments. Fate of removed seeds differed significantly among fragments; more buried seeds were found in the larger ones. Camera-traps showed the agouti Dasyprocta leporina as the principal consumer of A. aculeatissimum seeds. Seedling density was correlated with fragment size but independent of adult density, suggesting that habitat loss affects recruitment patterns of A. aculeatissimum through reduced quality of dispersal and increased predation SEED RAIN IN ATLANTIC FOREST FRAGMENTS AT DIFFERENT LEVELS OF HABITAT ISOLATION. PIVELLO, VÂNIA R.; Petenon, Daniela; Meirelles, Sérgio T.; Jesus, Flávia M.; Vidal, Mariana M.; Alonso, Regina; Franco, Geraldo C. Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05598-900, Brazil, vrpivel((AT))ib.usp.br (VRP, DP, STM, FMJ, MMV, RASA). Instituto Florestal de São Paulo, São Paulo, SP, 04301-900, Brazil (GCF). Habitat fragmentation may affect seed dispersal according to landscape pattern and community dispersal strategies. We compared the seed rain of three Atlantic forest fragments (SP, Brazil) to evaluate the influence of habitat connectivity and edge effect in the seed composition. Seed traps were placed at the border and centre of one large (175 ha) and 2 small fragments (around 5 ha), being one isolated in an agricultural matrix and the other connected to the large one by a corridor. Seeds were identified and classified according to species habit, functional group and main dispersal agent. The independence of these seed attributes were tested against their position in the fragment (centre/border), and the abundance of each seed type according to the fragment isolation, through chi-squared, DCA, ANOVA + Dunnet, and Spearman correlation analysis. The majority of the 27,873 seeds belonged to zoochoric trees of the early successional phases. Species richness was similar in all fragments, but higher in the centre of the large and small-isolated fragments. The small-isolated fragment was associated to late anemochoric tree species, and the smallconnected fragment to early and zoochoric species. Vines were associated to the borders of small fragments. Edge effects were stronger in the small-connected fragment SYNERGISTIC EFFECTS OF HABITAT DISTURBANCE AND FRAGMENTATION ON AMAZONIAN FOREST VERTEBRATES. MICHALSKI, FERNANDA; Peres, Carlos A. Centre for Ecology, Evolution & Conservation, University of East Anglia, Norwich, NR4 7TJ, England, f.michalski((AT))uea.ac.uk (FM, CP). Instituto Pró-Carnívoros, C.P. 10, Atibaia, SP, 12940-970, Brazil (FM). Habitat fragmentation has been shown to influence the abundance, movements and persistence of many tropical forest species. Here we examine the effects of forest patch and landscape metrics, and levels of forest disturbance on the species diversity, and guild structure of midsized to large-bodied vertebrates in 23 forest patches in a highly fragmented forest landscape of southern Brazilian Amazonia. Line-transect census, armadillo burrow census, camera-trapping, and habitat sampling were carried out during 14 months (2003-2004) in the Alta Floresta region, Mato Grosso, Brazil. Forest patch area was the strongest predictor of vertebrate occurrence and abundance. Landscape metrics (e. g. distance from source areas) were also important determinants of the persistence of forest vertebrate species. Anthropogenic disturbance including surface wildfires, timber extraction and hunting had detrimental effects on the persistence and abundance of some species over and above those of fragment size. Different species ranged in their responses from highly sensitive to highly tolerant to forest fragmentation. A threshold area of approximately 100 ha appears to be the minimum patch size required to sustain 52.4% to 76.2% of vertebrate species, whereas patches of around 1,000 ha showed full assemblages of large vertebrates, including white-lipped peccaries and large predators TROPICAL RAIN FOREST RESPONSE TO STAND REPLACING DISTURBANCE: PLANT FUNCTIONAL GROUPS, RARITY AND LONG-TERM FOREST DYNAMICS IN NORTHERN COSTA RICA. FINEGAN, BRYAN; Nasi, Robert; Zamora, Nelson. Centro Agronómico Tropical de Investigación y Enseñanza (CATIE), Turrialba 7170, Costa Rica, bfinegan((AT))catie.ac.cr; Centre for International Forestry Research (CIFOR), c/o CIRAD, Campus International de Baillarguet, TA 10/D, 34398 Montpellier, France, r.nasi((AT))cgiar.org; Instituto Nacional de Biodiversidad, Santo Dominago de Heredia, Costa Rica, n.zamora((AT))inbio.ac.cr. Which of the hundreds of tree species in degrading tropical landscapes are most threatened? We sought insights using long-term permanent sample plot (PSP) studies and multidimensional ecological groupings. Fifteen years of data > 10 cm dbh were from secondary forest (three 1.0 ha PSPs at our "core" site, light use, age range 15 - 41 years) compared with mature forest (seven PSPs, core site plus two others). We assigned 260 core site species to the functional groups (FG) diameter growth rate (DGR) adult height (AH), dispersal syndrome (DS) and to log2 abundance classes (log2N) in mature forest at local (core site) and landscape (34 PSPs at 16 sites) scales. Individuals of canopy species were overrepresented in secondary stands, mid-canopy and understorey species underrepresented, due to slow DGR rather than DS. The most speciose mature forest DGR/log2N classes, slow-growing species with N <16, contributed disproportionately to reduced species-richness in secondary stands. Species-richness of underrepresented groups increased unambiguously over time though N did not; those of overrepresented groups varied little. These results increase understanding of floristic response to disturbance and its possible functional consequences but only emphasize the need for habitat protection to conserve tropical tree species. These analytical tools are now being applied to the study of logging and edge effect impacts LEAF-CUTTING ANTS NESTS IN FOREST FRAGMENTS: A THREAT TO SHADE TOLERANT SPECIES? CORRÊA, MICHELE M.; Bieber, Ana G.; Tabarelli, Marcelo; Wirth, Rainer; Leal, Inara R. Departamento de Botânica, CCB, Universidade Federal de Pernambuco, Recife, PE, 50.670-901, Brazil, correamm((AT))uol.com.br (MMC, AGB, MT, IRL). Dep. of Plant Ecology & Systematics, University of Kaiserslautern, P.O. box 3049, 67653 Kaiserslautern, Germany (RMW). The construction and maintenance of nests by leaf-cutting ants create understory gaps, which modify vegetation structure and light intensity at ground level. Here, we test if nests of Atta cephalotes reduce the proportion of shade tolerant species in forest fragments. We hypothesized that these species present lower frequency near ant nests because of their low light requirement. We selected eight equal-sized nests at the edge and eight in the interior of a 3.500- ha fragment of Atlantic forest in Serra Grande, Alagoas. For each nest we established four plots: (1) over the nest, (2) contiguous to the first plot, (3) 5 m far from the second plot, and (4) 20 m far from the third plot. We identified all trees from 1.5 to 10 cm DBH and gro uped species as shade tolerant or intolerant. The proportion of shade tolerant species was positively correlated with distance from the nest but only in colonies of the forest interior. The forest vegetation around edge nests was not affected, probably because the proportion of shade tolerant species is naturally lower in this habitat. In a fragmented environment the decreased abundance of shade tolerant species caused by Atta nests threats the few remnants of primary forest BIOTIC SEED DISPERSAL DECREASE IN SECONDARY ATLANTIC FORESTS OF RIO DE JANEIRO STATE, BRAZIL. CARVALHO, FABRÍCIO ALVIM. Laboratório de Ciências Ambientais (LCA/CBB), Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, RJ, 28015-620, Brazil, fabricioalvim((AT))yahoo.com.br. The objective of this study was to check the differences in the proportion of tree seed dispersion syndromes between secondary and mature forests in the submontane ombrofilous Atlantic Forest of the Rio de Janeiro coastal lowland, Brazil. Lists of species of nine secondary and five mature forests were used. Dispersion syndromes were determined through literature data. Biotic seed dispersal mode (zoocory) prevails in the sixteen forests analyzed (range from 64% to 87%). Significant differences were found between the two forest types (t test, p<0,05), and the proportion of biotic dispersion were greater in mature forests (83,2% versus 67,8%). Secondary forests show a decrease in the proportion of tree species dispersed by large-bodied frugivorous vertebrates, belonging to Lauraceae, Myrtaceae and Sapotaceae. It was verified that, as the composition of the seed disperser fauna appears to be one of the major filters for the seedling recruitment in succesional forest landscapes, the absence of adequate associated fauna is a risk to natural forest regeneration and colonization of new secondary forest patches. Thus, programs of restoration and management of secondary forests in this region must take in account the disperser-plant interactions to successful conservation and maintenance of these forest ecosystems LANDSCAPE STRUCTURE, EDGE EFFECTS AND NEST PREDATION IN SOUTHEASTERN BRAZILIAN ATLANTIC RAINFOREST. CANDIA-GALLARDO, CARLOS E.; Develey, Pedro F.; Metzger, Jean Paul. Laboratório de Ecologia da Paisagem e Conservação, IB, Universidade de São Paulo, São Paulo, SP, 05508-900, Brazil, candiagallardo((AT))yahoo.com.br (CECG, JPWM). Birdlife International, Brazil Programme, Barueri, SP, 06474-010, Brazil (PFD). Numerous studies have linked high forest bird nest predation rates to fragmentation and habitat edges. These evidences mainly come from studies conducted in the northern hemisphere, with low or no support in the Neotropics. Our aim was to test the effects of landscape structure, edge distance and small mammals abundance on artificial nest predation rates, in an Atlantic Rainforest region, one of the world's top five hotspots. We sampled 12 fragments (ranging from 1.4 to 175 ha) and Morro Grande Forest Reserve (9400ha). We did not find any significant effect of fragmentation or edge on nest predation. Nevertheless, we found a positive relation between big-eared opossum (Didelphis aurita) abundance and nest predation. These findings corroborate most studies conducted in the Neotropics, which do not give support to the "edge effect on nest predation hypothesis". Our results indicated that, at least in the study region, the major nest predators (e. g. opossum) do not avoid forest interiors; instead they may even prefer them. If this hypothesis is correct, even forest interior nests could suffer high predation rates. To avoid unusual high rates of predation in fragmented landscapes, efforts should be done to identify factors affecting predators abundance REGENERATION OF SEASONAL RAIN FOREST IN A PROTECTED AREA IN THE FLOODPLAIN OF THE HIGH PARANÁ RIVER, BRAZIL. CAMPOS, JOÃO BATISTA; Dickinson, Gordon. Instituto Ambiental do Paraná, Av Bento M. Rocha Neto, 16, 87.030-010, Maringá, PR, Brazil, redebio((AT)) wnet.com.br. University of Glasgow, Department of Geography and Geomatics, Scotland—UK, gdickinson((AT))geog.gla.ac.uk. This study analyses patterns of forest regeneration in the floodplain of the High Paraná River, Brazil. The Protected Area of Porto Rico Island, 100 hectares in extent, had been deforested for cattle ranching. Cattle were removed in 1996, the island given protected status and forest allowed to regenerate. We investigated forest regeneration using a series of phytosociological transects along environmental gradients. The locations of the transects were established accurately by use of marked trees and GPS, surveyed in 2002, 2003 and 2004. Phytosociological types, functional groups and diversity indices were established. We compared these data with nearly undamaged natural forest sites. The regeneration showed spatial and temporal patterns indicating three seral stages of development to climax forest, with dominance of disturbancetolerant pioneer tree species around the island's shore. The regenerating forest was less species diverse than primary forest. However around remaining mature climax forest trees, left to shade cattle, there was more species-diverse climax forest developing. We propose that these trees can be used, with site management, to reproduce forest closer to natural forest than that developing by regeneration alone. This will reduce "time tax" losses PLANT DIVERSITY OF UNDERSTORY IN THREE REFORESTATION AREAS IN THE NORTH OF PARANA STATE, BRAZIL. BENATO, TAIS; Barbosa, Carlos Eduardo A.; Jardim, Pedro S.; Torezan, Jose Marcelo. Departamento de Biologia Animal e Vegetal, Universidade Estadual de Londrina, Londrina, PR, 86.051-990, Brazil, torezan((AT))uel.br. Forest cover in the Parana State represents less than 10% of the existent in the early 20th century. This situation difficults the regeneration of degraded lands through secondary succession, due to the lack of seed sources. In this context, reforestation programs may accelerate the process. We analyzed the success of reforested areas - understory composition and structure, and the influence of environment factors on diversity and the aspects of the ecology of the species sampled. Three reforestation areas, implanted 9, 10 and years ago, were sampled, with six plots of 25 m2 each, including plants over 10 cm of height. Data over the crown cover, herb cover, light intensity and distance from fragments were collected. There were 139 species sampled, belonging to 41 families. The most common dispersion syndrome was zoochory, followed by anemochory and autochory, highlighting the importance of fauna dispersion. Within the sampled species, 73 are trees, 28 lian as and 19 bushes. There is a slight tendency of a richer understory as the herbaceous cover and the fragments distance decrease, both factors explain richness and abundance. Crown cover and light intensity were not significant to any index analyzed. Tree species were more representative, maintaining the successional process. DENSITY OF LEAF-CUTTING ANTS IN REMNANTS OF THE ATLANTIC FOREST OF NORTHEAST BRAZIL. ALMEIDA, WALKIRIA R.; Araújo Jr., Manoel V. de; Barbosa, Veralucia S.; Silveira, Úrsula A.; Wirth, Rainer; Leal, Inara R. Departamento de Botânica, Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Recife, PE, 50.670-901, Brazil, walreal((AT))yahoo.com.br (WRA, MVAJr, VSB, UAS, IRL). Dep. of Plant Ecology & Systematics, University of Kaiserslautern, P.O. box 3049, 67653 Kaiserslautern, Germany (RMW). In this study, we investigated whether fragmentation and habitat loss of the Brazilian Atlantic rainforest affected the population density of leaf-cutting ants (LCA). The study was conduced in 14 remnants at Usina Serra Grande, Alagoas, where a 3.500-ha fragment, the largest of the Pernambuco Center of Endemism, was used as the control area. Using the transect method, we surveyed colonies of Atta cephalotes and Atta sexdens in 67.1 ha of forest. The colony density was 1.75 ± 6.35 ha¡1 in the interior of the control area (22 colonies in 39.5 ha), 5.0 ± 7.42 ha¡1 in the edge (< 100 m) of the control area (21 colonies in 4.2 ha), and 2.6 ± 2.38 ha¡1 in the fragments (46 colonies in 23 ha). Although the difference in colony density across the three habitats was not significant (H = 4.6549, gl = 2, p = 0.0975) LCA appear to accumulate in forest fragments, and especially along the forest edge. This indicates that both area loss and edge creation affect population regulation in LCA. The fragmentation-related propagation of LCA may, in turn, considerably influence vegetation dynamics of small and large remnants of Atlantic rainforest (see poster by Corrêa et al.). Society for Conservation Biology - Brasilia 2005 News index | RSS | Add to MyYahoo! Advertisements: Organic Apparel from Patagonia | Insect-repelling clothing |
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