A high-diversity primate community consisting of 13 species was examined at an entirely undisturbed and remote terra firme forest near the headwaters of the Urucu River, Amazonas, Brazil. Twelve of these species used a 900-ha study plot, located 4 km or more inland from the river, and comprised a total group density of 16 groups km−2, an overall density of 146 individuals km−2, a crude community biomass of 381 kg km−2, and a metabolic biomass of 278 kg0.75 km−2. These species were occasionally found together within small (≥1 km2) areas of forest, so long as they included the full complement of available forest types. More frequently, however, only half the species co-occurred in a single habitat type at any one time, reflecting a relatively consistent pattern of subcommunity spatial organization. Habitat generalist species making extensive, yearround use of the predominant habitat type (high forest), were common, whereas habitat specialists were uncommon to very rare, and confined to minor habitats. Those species coexisting throughout the year in high forest were found to segregate vertically from one another. These and other modal patterns of community structure were disrupted seasonally by long-distance, inland movements by two ‘igapó’ forest species living in large groups – squirrel monkeys and white-face capuchins – to high forest areas, which apparently resulted from a food bottleneck in their habitat. Another species found in large groups – woolly monkeys – also exercised seasonally vagrant movements within the high forest matrix, which coincided with periods of greatest scarcity of mature fleshy fruits.

In 14 forest plots (36 m2) all terrestrial plant species were recorded before slashing and burning of the vegetation. During subsequent cultivation with rainfed rice all resprouting plants were registered in permanent plots (72 m2). The fields studied (one per forest) covered all combinations of forest type and soil usually cultivated on local farms. Forest plots (total 409 species) and field plots (358 species) had 226 species in common. Most resprouting plants were woody. Though nine forests in the sample were secondary, 70% of resprouting plants belonged to primary forest species and with three exceptions, these species did not regenerate by seed.

Experiments in one field inlcuded: different intensities of initial burning, weeding (none, once, twice) and length of the rice cultivation period (1, 2, 3 y). Resprouting plants were monitored in permanent plots (108 m2) during 3 y of cultivation and 2 y of fallow. More plants resprouted after a mild initial burning (5.8 plants m−2) than after a burn of normal intensity (1.4 plants m−2). Weeding and prolonged cultivation strongly reduced species diversity but plant densities were less affected because some climbers and trees were apparently stimulated and expanded.

Fields abandoned after one rice harvest had, within six months, a closed forest canopy of pioneer trees emerging from the pre-existing seed bank and from the growth of resprouting trees. Prolonged cultivation (3 y) destroyed the pre-existing seed bank but affected sprouting plants less, these being the only component in the vegetation able to shade out weeds and forbs such as Chromolaena odorata.

Study of forest dynamics commonly requires measurement of canopy gap size. Hemispherical photographs can be analysed to provide various measures whereby gaps can be ranked in order of size. For ten artificial gaps in a Bornean tropical rain forest these measures were better correlated with gap microclimate than gap area measured physically on the ground. All these measures are however relative. For detailed (e.g. ecophysiological) studies the greater detail provided by absolute measures of photosynthetically active radiation (PAR) are required. Long term PAR values can be computed from hemiphots so long as measurements in the open nearby are available. Correction for cloudy weather is essential. Computed and measured PAR are compared for the test gaps. Both have inherent limits which means that below c. 15% canopy openness, differences in PAR between gaps cannot be assessed accurately.

The effects of forest habitat, canopy light condition, vertebrate herbivory and species mean seed size on growth of tree seedlings were evaluated for six widely different species of North Queensland tropical rain forests. Two forest localities differing in size and rainfall intensity were used for the trial. In each forest, seedlings were transplanted three weeks after germination into small to medium-sized canopy gaps and into the forest interiors, with half protected by cages and the other half unprotected. Growth measurements were made over a period of 16 months. All growth parameters examined differed significantly between the six species. At the end of the study period, for most species, forest site and protection from vertebrates did not affect seedling biomass. For all species, growth was higher in gaps than in forest interior, but most biomass allocation patterns did not differ between the two habitats. This was attributed to the small difference in photosynthetically active radiation (PAR) levels between the two habitats (interior, 0.48–2.53% PAR; gap, 3.58–7.09% PAR). Between species, seedling growth in the forest interior and sensitivity to increasing light were significantly correlated with initial mean seed size. The growth ability of the six species in and out of canopy gaps is discussed in terms of regeneration status of forest tree species.

Two kinkajous (Potos flavus) were equipped with radio-transmitters and tracked during a 14- and a 7-day period in a primary forest of French Guiana. Both individuals were strictly nocturnal. They moved between food patches (flowering or fruiting trees) during c. 65% of the night, visited food trees during c. 20%, while the remaining time was devoted to rest. Rest time tended to peak in the middle of the night, whereas distances travelled peaked at the beginning and the end of the night. Minimum and maximum home range areas, estimated from minimum area and minimum convex polygon methods respectively, reached 15.7 and 17.6 ha in the female, 26.6 and 39.5 ha in the male. Mean daily activity area amounted to 5.5 ha in the female, 11.3 ha in the male. Distances travelled in a night averaged 1495 m for the female, 2540 m for the male. In contrast to the female, the male used the periphery more intensively than the centre of its home range. Both individuals occupied several roosts located in the canopy, but one far more frequently than the others. The male's roosts were all situated in the periphery of the home range.

Kinkajous were observed feeding on flowers or fruits of 15 plant species. Among the 10 species exploited for fruits, at least seven were dispersed. Dispersal distances averaged 200 ± 75 m (13 seed dispersal occurrences for 16 defecations), while seed transit time varied from 45 min to 3 h 35 min. P. flavus appears to be nocturnal, solitary, a generalist fruit and flower-eater and an important seed dispersal agent.

We sampled riparian frogs along 18 streams at eight localities in Borneo. At four of these sites we sampled during more than one year. Altogether 49 species were included in our study and total sample size was 13,249. We measured overlap in species occurrences and arrays of abundances within and among localities. Variation over the time span of our study was minor within communities. Overlaps between streams at a locality were generally higher than overlaps of pairs of streams from different localities. Environmental variation, particularly in stream width and gradient, had a clear effect on both intra-and inter-locality overlaps. Although rainfall varied between localities and within localities over time, that variation did not seem to affect overlaps among or within communities. Environmental factors did not account for all differences in overlaps between communities. Instead, regional processes, perhaps the timing of barriers or speciation events, appear to have been responsible for geographic restrictions of several species, leading to variation in overlap values.

Floristic and structural comparisons and a numerical classification were performed to identify the priority areas for conservation of genetic resources in central Brazil. The main type of woody vegetation, cerrado sensu stricto (savanna woodland with 10–60% tree cover), was sampled under a uniform methodology in six selected sites (total sample of 6 ha) scattered in a physiographic unit called the Pratinha Plateau located between 15–20° S and 46–49° W. A total of 6971 trees belonging to 139 species and 42 families was measured. Each site had a combination of 50–80 species and approximately 30 families but only 22 species from 14 families were common to all sites. Similarity decreased with distance, indicating the existence of geographical gradients as the physical characteristics were relatively uniform and the soils were dystrophic at all sites. The most dissimilar sites, in the localities of Patrocínio-MG and Paracatu-MG were recommended for the establishment of conservation units. The already existent conservation units arc all clumped in the Federal District and are not enough to protect the genetic heritage of the plateau. Floristics and phytosociological surveys based on land system zoning were recommended as useful tools in planning conservation areas at a regional level to preserve the maximum biodiversity.

Density and biomass of four ungulate species, elephant (Elephas maximus) and seven other mammal species were estimated in an area of about 50 km2 in a dry tropical forest in Huai Kha Khaeng Wildlife Sanctuary, western Thailand. Density estimations employed line transects, using either direct sightings or indirect signs. Total biomass of these ungulates and elephant was 1450 kg km–2 which was lower than that found in a well protected and managed area of similar forest, Nagarahole National Park, in India. This is due to the intensive poaching activity and the lack of wildlife management in this study site. Three species of ungulate, banteng (Bos javanicus), gaur (Bos gaurus) and sambar deer (Cervus unicolor), contributed over 70% of the estimated herbivore biomass. This situation is similar to that found in other parts of Asia. The high biomass of a subterranean mammal, Cannomys badius, has not been documented elsewhere in Asia; this species probably influences the forest dynamics and ecology of small carnivores in this area.

Present theories of tropical rain forest regeneration dynamics suggest that different tree species specialize on the microclimates of different sizes of canopy gap. A detailed analysis of the microclimates of closed forest and 10 canopy gaps of different sizes was carried out in lowland dipterocarp rain forest, Sabah, Malaysian Borneo. It reveals that gaps exhibit considerable spatial and temporal variation in microclimate. As a consequence the relationship between microclimate and gap sizes is not simple. Gaps of the same size do not necessarily have the same microclimate and may favour the growth of different seedling species. Chance location and timing of gap creation play an important role in regeneration dynamics.

We report long-term observations on leaf herbivory in the mangroves Rhizophora mangle and Avicennia germinans, on the Placencia Peninsula of Belize. We labelled and traced leaves and recorded the amount of damage appearing over a period of 310 days. Herbivores had damaged 1–4% of total mean leaf area within the first 10 days, but damage rates levelled off thereafter, to a final total of 4–10% damage. Herbivores did not concentrate on leaves of younger age classes. Rhizophora mangle growing in the high tidal zone (HHW) exhibited the highest initial and total attack rates at all but the final sampling dates. We also documented the dynamics of injury expansion and necrosis following artificial injury to seedling and tree leaves. Artificial holes in leaves were associated with higher subsequent rates of herbivory that varied among leaf age classes, and particular damage types were more prevalent in previously injured leaves. Artificial holes expanded significantly more in young leaves of both species. Holes in young leaves of both species expanded by up to 45.1% in area over 50 days, consistent with a similar study in Australia. Substantial necrotic areas developed around the injury site; a secondary effect of damage not often considered in herbivory studies. We discuss the implications of hole expansion and necrosis in estimating error in herbivory measurements. Temporally dynamic studies of herbivory are especially needed in tropical systems that show non-deciduous phenologies and long-lived leaves.

The ecology of the Sri Lankan elephant in the Wasgomuwa Strict Nature Reserve and its environs is reported for the first time. Seasonal changes in the availability of grazing sites influenced changes in the home range of elephants. Availability of such sites in the wet season was limited by agricultural activities. Paddylands, after the harvest of the rice crop in the late wet season, became important dry season grazing sites. In the Reserve and areas outside its southern boundary on the left bank of the Mahaweli River, (a) female herds were seen more often than solitaries (b) female herds were larger and had a higher than expected number of juveniles in the dry than in the wet season (c) about 45% of the individuals were juveniles and (d) 7.4% of adult and sub-adult females had calves. Conflict between elephants and farmers will be most intense along the southern and eastern boundaries of the Wasgomuwa National Park, established in 1984 by the addition of new areas predominantly to the northern part of the Wasgomuwa Strict Nature Reserve.

Data on litterfall, litter layers accumulated on top of the mineral soil and layer mineralization collected for three years in a tropical rain forest at Pernambuco, Brazil, were implemented on a simulation model. Litterfall was collected biweekly using 11 collectors 1 × 1 m. Every three months, 20 litter mat samples, 0.5 × 0.5 m, were collected, divided into the L, F and H layers and the CO2 evolution from each litter layer was determined in the laboratory. Litterfall, in the three years, averaged 7.8, 8.3 and 8.2 Mg ha-1 y-1, most of it leaves. Litter mat masses varied widely from place to place (15–90 Mg ha-1) and the overall averages were 5.6, 7.6 and 26.1 Mg ha-1 for the L, F and H layers, with CO2 evolution averages of 2.27, 0.507 and 0.123 mgC g litter C-1 day-1. According to the model, the L layer had a high turnover rate, losing 4.7 Mg ha-1 y-1 through mineralization and 3.4 Mg ha-1 y-1 transferred to the F layer. Values for the F and H layers were 1.4 and 1.2 mineralized and 2.0 and 0.8 Mg ha-1 y-1 transferred. Thus, it would take 2.1, 6.7 and 39 years for newly fallen leaves to be mostly fragments, to be transformed to humus and to be incorporated to the soil organic matter, respectively. Variations of litterfall throughout the three years would have little effect on the system which was not very sensitive to litterfall changes, except for the top layer.

This study focused on relationships between a tropical forest grasshopper and a major group of its host plants. Microtylopteryx hebardi (Acrididae:Ommatolampinae) at La Selva Biological Station, Costa Rica, feeds on understorey palms as well as other understorey plants. We assessed leaf damage levels in populations of three geonomoid palm species (Geonoma cuneata, Geonama congcsta, Asterogyne martiana), investigated feeding response of M. hebardi to the three palms, and examined leaf characteristics presumed to be important to herbivores. In understorey and gapedge habitats, total leaf damage did not differ significantly between palm species. In the centre of small light gaps, where M. hebardi was most abundant, total leaf damage and total herbivory on G. cuneata was equal to that on the other species, but herbivory attributable to grasshoppers was significantly greater. Female M. hebardi showed strong preference for G. cuneata over the other palm species in laboratory feeding trials. Experiments to elucidate the proximate basis for this feeding preference showed that grasshoppers preferentially bit filter paper discs containing cuticular wax extract of G. cuneata. In consumption and digestibility experiments, grasshoppers consumed more fresh weight of G. cuneata and gained more weight per unit time spent feeding on this species. Leaves of G. cuneata had the highest percentage water content, highest fresh and dry mass per unit leaf area, and the lowest percentage crude lignin among the three palms studied. These factors may partially explain the preference of M. hebardi for G. cuneata, which was reflected in higher herbivory rates incurred by G. cuneata in sites where M. hebardi was locally abundant.

Dung beetles attracted to howler monkey (Alouatta palliata) and coati (Nasua narica) dung were studied for an annual cycle in the tropical rain forest of Los Tuxtlas, Mexico. Pitfall traps set for 24 h month−1 captured 1567 dung beetles of 21 species. The species Canlhidium martinto, Deltochilum pseudoparile and Canthon femoralis accounted for 62% of all individuals captured. While species overlap was high (> 80%) between diurnal and nocturnal samples and between howler monkey and coati dung baits, coati dung attracted species such as C. martinezi, D. pseudoparile and Onthophagus rhinolophus while species such as C. femoralis and Copris laeviceps were numerically dominant at howler monkey dung. Thirteen non-ball rolling dung beetle species and eight ball-rolling species accounted for 43% and for 57% of all beetles captured respectively. Dung beetles were present and active in all months of the year, but occurred in higher numbers between the months of March and October, when temperatures were higher. Relative abundance of howler monkey and coati dung in the rain forest of Los Tuxtlas was estimated at 11.2 g (fresh weight) ha−1 day−1 and at 13.0 g ha−1 day−1 respectively, a seemingly low amount for the large number of scarabs attracted to the dung.