(1) During 1978–1981, marked individuals of 107 species of treelets and shrubs in three forest types between 1300–1650 m elevation at Monteverde, Costa Rica, were monitored at monthly intervals for behaviour of leafing, flowering, and fruiting.

(2) Although there was not a pronounced seasonal pattern of leafing activity, more species produced new leaves in the dry season. Species that flush large quantities of new leaves do so more commonly in the drier months. Leaf loss was gradual and unobtrusive in species observed.

(3) Flowering activity was greatest in the late dry season and early wet season. Most species exhibited extended flowering; only 15% of the species were massively flowering. Massive flowerers showed less seasonality than extended flowerers.

(4) Of the species studied, the majority had relatively unspecialized flowers which were visited by a variety of insects; small bee-pollination was the next most common, followed by hummingbird, beetle, settling moth, sphingid, butterfly, large bee and fly pollination (the pollination system of 18 species was unknown). Hummingbird pollinated species showed little seasonality of flowering when compared with species exhibiting small moth, and beetle pollination syndromes, as well as those with unspecialized flowers.

(5) The vast majority of species studied have fleshy fruits (sarcochores). Fruiting activity was less markedly seasonal than flowering. Species with fruit are more numerous in the second half of the year (the wet season and early dry season). The second year of the study saw substantially fewer species in fruit than the first year; this is attributed to the greater than usual rainfall and inclement weather during the peak flowering season.

(6) Cloud forest shrub and treelet phenology is compared with patterns of other forests that have been studied. In general, the greater the rainfall, the less seasonality of flowering and fruiting is seen. Although Monteverde is very wet, rainfall is intermediate between that of lowland dry and lowland wet forest in Costa Rica. Seasonality of flowering and fruiting at Monteverde is more pronounced than at La Selva (wet) and less obvious than in Guanacaste (dry).

The herpetofauna of a floodplain monsoon rain forest in northern Australia is composed primarily of species from non rain forest habitats. The majority of frog species use rain forest as a seasonal refuge, and there is a marked increase in numbers during the dry season. Faunal richness lies within limits expected on the basis of the length of the dry season and species richnesses of non-Australian faunas. There are few lizard species and an abundance of frog species (none of which is a rain forest specialist) in comparison to rain forest herpetofaunas in other tropical regions. The impoverished lizard fauna, and the paucity of rain forest specialists may be because (a) seasonal invasion of rain forest by frogs prevents evolution of, or colonization by, specialists or (b) rain forest specialists may not have been able to cross semiarid habitats separating the Northern Territory from eastern Australian rain forests. The herpetofaunas of monsoon forests in Cape York Peninsula may provide a means of distinguishing between these hypotheses.

A unique stand of mangroves of the genus Bruguiera occurs on the shore terrace at Hosnies Spring, Christmas Island, Indian Ocean. The mangrove stand, of about 0.33 ha, occurs 120 m inland and over an elevational range of 13 m, from 24 to 37 m above sea level. It is flooded by freshwater from a spring which trickles over a partially-cemented calcsinter concretion gravel with mud. Trees reach 30–40 m high, and 80 cm diameter breast height. The size structure is bimodal with few trees in the 10–25 cm dbh size classes, but abundant propagules, seedlings and saplings. The shore terrace contains corals, some in their position of growth, and has been shown by Uranium-series dating to be Last Interglacial in age. Several alternative explanations of how the mangroves reached this site are examined. One explanation is that this stand of mangroves has persisted at the site for approximately 120,000 years since the Last Interglacial. While this cannot be proved it does appear that the stand is relict and is actively regenerating in this unusual location.

In Costa Rican tropical wet forest the distribution of seedlings of most tree species colonizing 51 tree-fall gaps is clumped, probably because of differences in the proximity of gaps to fruiting trees. Different gap zones (root, bole and crown) are more similar to one another, in terms of their species composition, than they are to other zones in the same gap. This nonrandom pattern is established soon after gap formation, indicating that mortality of young seedlings is both high and related to gap zones. Some tree species are strongly positively associated with one of the gap zones, whereas others are associated with the age of the gap at the time the census was taken or the species of tree whose fall caused the gap. Root zones are dominated by fewer species than are bole or crown zones. Results are consistent with the assumption that an initial random distribution of seedlings is quickly changed to a strongly non-random pattern by selective mortality of seedlings of different tree species in the different gap zones. The internal heterogeneity of gaps is probably one of the factors helping to maintain the high tree species richness characteristic of tropical wet forests.

The distribution and microhabitat preference of the freshwater prawn, Caridina singhalensis, endemic to Sri Lanka, was determined. The species is now restricted to a 10–15 km stretch of the Behihul Oya headwaters, its distribution being determined by physiography and agricultural development.

Beds of Isolepis fluitans support some 76% of the adult population, at mean monthly densities of around 210 individuals m−2. Aponogeton jacobsenii beds and roots of marginal vegetation beneath overhanging banks support about 12% each, at mean monthly densities of 41 individuals m−2. The prawn produces young all year round but a peak in the number of ovigerous females occurs from September to January. Only juveniles produced after the rains appear to survive in great numbers. The submerged roots of marginal vegetation form a nursery area for about 45% of the annual output of young. Conservation plans for this endangered species need to take account of the particular importance of I. fluitans and root habitats to C. singhalensis.

A total of 52,467 wind-dispersed seeds from 14 tree and 32 liana species fell into 1720 seed traps in 43 paired light-gap and adjacent forest sites on Barro Colorado Island, Panama. Summed at the community level, many more wind-dispersed seeds were collected from light-gaps (61%) than from forest sites (39%). They accumulated from March through May, 1984 to a density of 328 m-2 in gaps and 207 m-2 in forest sites. In contrast, only 33% of the total of 2782 non-wind-dispersed seeds were collected in gaps. Due to the extreme heterogeneity of the seed rain, these differences between gap and forest sites were not statistically significant at the community-level. Gap sites received more wind-dispersed seeds than adjacent forest sites in only 20 of 43 locations and in 13 of 20 species, especially those with individuals of high fecundity near gap sites. Of the estimated 105 million wind-dispersed seeds contributing to the seed rain of the 50 ha study plot, only 4.1% were dispersed to the rare gap sites that enhance the establishment and growth of seedlings for many of these species.

Abundance and density data for terrestrial arthropods from the forest floor, trunk and canopy of primary and secondary dryland forests near Manaus, Brazil are given.

Early studies comparing adult and juvenile tree populations in West Africa described a contrast in flonstic composition between the two age classes. These studies have been mis-represented in more recent literature, and confusion has arisen over their interpretation.

Similar comparisons are reported here for six forest sites in Ghana. At any one site, clear differences in composition were recognized between adult and juvenile samples, but in terms of the variation in flonstic composition over the whole of the forest zone, they are slight and forest types appear to ‘breed true’.

At one site, Kade, compositional differences between size classes are fully described for all canopy species on a 0.25 ha plot. There was an abrupt change in composition at about 30 cm gbh. At this site, mortality rates for trees >30 cm gbh were greater amongst species with a high proportion of juveniles in the population. At other sites, changes in composition were sometimes abrupt, occurring at various size classes, or were more gradual.

The populations of some species included a large number of juveniles at all sample sites, but the converse, where species always have low densities of juveniles, were not seen. The possible implications of these results for future canopy composition are discussed in relation to temporal equilibrium, or lack of it, in tropical forest composition.

We describe forests from three areas of Jamaica, all on White Limestone but with markedly different rainfall regimes. The areas are Hog House Hill in the north-east with lower montane rain forest at c. 450 m altitude with a rainfall of c. 4000 mm yr−1; Broom Hall in the centre of the island with evergreen seasonal forest at c. 670 m altitude and with a rainfall of c. 1600 mm yr−1 and a marked dry season; and Round Hill near the south coast with dry semi-evergreen forest at c. 300 m altitude with an irregularly distributed rainfall of c. 1000 mm yr−1. Species lists were made from c. 180 ha at Hog House Hill, c. 5 ha at Broom Hall and c. 50 ha at Round Hill, and detailed inventories made of five sample sites of c. 1000 m2, two at Hog House Hill, one at Broom Hall and two at Round Hill.

At Hog House Hill we listed 280 vascular plant species, including 118 species of trees and larger shrubs; at Broom Hall 247 and 135; at Round Hill 129 and 81. Species-area and species-individuals curves confirm that Broom Hall was richer in tree species than Hog House Hill. The wetter forests contain high proportions of species endemic to Jamaica: 40% of the total flora at Hog House Hill and 36% at Broom Hall. Canopy height decreased from c. 26–28 m at Hog House Hill to c. 13–24 m at Broom Hall to c. 8–15 m at Round Hill. Predominant leaf size decreased from mesophyll at Hog House Hill to notophyll at Broom Hall to microphyll at Round Hill.

Compared with forests on other Caribbean islands, the Jamaican forests appear to be as species-rich as any, but lower in stature than natural forest in Trinidad and Dominica. Continental Neotropical forests are both more species-rich and taller.

Fruit production, frugivore foraging activity and seed dispersal was studied at 10 Cymbopetalum baillonii (Annonaceae) trees during an entire fruiting season. Fruits dehisced during the first six months of the year offer to potential dispersal agents a package of 8–24 arillate seeds. Insects and fungi, however, killed up to 14% of the seeds potentially available for dispersal before fruit dehiscence. Visitation by 24 species of birds and one mammal to the trees closely followed the availability of arillate seeds. The foraging activity of Peromyscus and Heteromys rodents accounted for ≥ 80% mortality of the seeds deposited under the crown of the parent tree. Among those seedlings that became established under the crown mortality was ≥ 90% after 12 months. Seeds dispersed under conspecific fruiting trees experienced intense predation by vertebrates. Field experiments showed that seeds and seedlings planted ≥ 30 m away from adult trees survived significantly longer than those planted under the crown and at distances ≤ 30 m. An unequivocal advantage to dispersal away from the tree and under allospecific trees was evident from the data. A very narrow range of frugivores (N = 8 species) accounted for the quality component of dispersal services to the trees. The tree with the lowest animal visitation and fruit crop was the most efficient in the dispersal of its seeds.

In 1933/34 eight coppice plots were established in Brachystegia-Julbemardia (miombo) woodland at Ndola in the Copperbelt area of Zambia by the Forestry Department. These plots have been maintained under fire protection, annual early or late dry season burning since 1934/35. Before establishment stems over 20.3 cm girth at breast height were enumerated. Three of the eight plots (one fire protected and two annually early burnt) were enumerated in 1982, 48–49 years after establishment. In addition, a coppice plot at Chitwi, 16 km southwest of the Ndola plots, cleared in 1972 and left to regenerate naturally was enumerated in May 1982 and August 1986 to assess woody plant growth.

The density of stems over 20.0 cm girth in the 13-year-old coppice at Chitwi was 2.5 times that in an adjacent shelterbelt woodland. The stem density in the fire protected plot at Ndola in 1982 was 86% of the pre-felling density while in one of the early burnt plots it was 95% of the pre-felling density. The protected plot had the lowest species diversity after 49 years, largely because of the loss of 11 understorey species that were present before felling.

There were no significant differences in stem mean girth at breast height (gbh) of canopy species in the Ndola plots under fire protection and early burning regimes. Mean annual gbh increments of abundant species were estimated at 1.17–2.21 cm yr−1 and 0.59–1.42 cm yr−1 during 0–9 and 0–49 year age-periods, respectively. Estimated mean annual basal area increments for stems over 30 cm gbh were 0.35 m2 ha−1 for the 13-year-old coppice and 0.24–0.27 m2 ha−1 for the 49-year-old coppice. These results indicate a decrease in both gbh and basal area increment with increasing age of miombo coppice

Litterfall was measured monthly in ten 1 m2 traps in each of two 0.25 ha plots in the rain forest of Southern Bakundu Forest Reserve, Cameroon for 18 months from 1 July 1982 to 31 December 1983. Particular emphasis was placed on measuring species contributions and in relating litterfall to climatic factors; the litterfall data were also used in estimating leaf production. Annual litterfall ranged between 12.9 and 14.1 t ha−1 and was partitioned to leaves (61–66%), branches (23–38%), fruits and flowers (8–12%) and ephiphytes (0.8%). Emergents and top canopy species like Desbordesia glaucescens (evergreen) and Ceiba pentandra (deciduous) contributed more litter than the numerically dominant lower storey species like Cola lepidota and Diospyros spp. Litter fell throughout the year but was greatest during the dry season (November to March); litterfall was thus strongly negatively correlated with environmental moisture variables and could be predicted from its linear regression on time of year, throughfall and relative humidity. By correcting the leaf fall data for leaf weight losses due to grazing and re-translocation, leaf production rates of 10.2 to 11.2 t ha−1 yr−1 were estimated for the forest.

Thirty-four spedes of mosquitoes (Diptera: Culicidae) were collected at a series of human-bait catches designed to study evening crepuscular biting activity using the Nielsen crep unit, at a site at Peradeniya, Sri Lanka. Crepuscular biting profiles of seven species (Armigeres subalbatus, Aedes albopictus, Culex pseudovishnui, Cx. gelidus, Cx. fuscocephala, Cx. tritaeniorhynchus and Mansonia uniformis) were obtained. Modal periods for the onset of biting were analysed in six species: Cx. pseudovishnui, Cx. fuscocephala, Cx. gelidus, Cx. tritaeniorhynchus, Cx. quinquefasciatus and Ma. uniformis. Successions in the biting peaks and in modal onset of biting were seen in these species. Analysis of biting in Ar. subalbatus and Cx. pseudovishnui under high (clear sky) and low (cloud-overcast sky) light intensities showed earlier biting in both species under the latter conditions. The value of the Nielsen crep unit in making latitudinal comparisons is illustrated in Ma. uniformis, for which parallel data are available from Africa.

During the unusually extended breeding season of 1984/85 in Tsavo-East National Park, Kenya, Quelea quelea were sampled and moult patterns recorded. Particular attention was paid to individuals with an interrupted moult pattern. These were further classified as either having their moult arrested or suspended. Apparently, post-nuptial moult begins earlier in males than in females. Although the majority of quelea bred and moulted sequentially, these activities overlapped in many individuals and moulting suspended after the replacement of a few feathers. The initiation of post-nuptial moult before the cessation of breeding, followed by moult interruption, is evidence for the physio-ecological drive in quelea to complete their moult as soon as possible to prepare for the next breeding opportunity.