Sustainable ecotourism in Costa Rica: the Monteverde Cloud Forest Preserve

The paper discusses the sustainability of the Monteverde Cloud Forest Preserve in the context of Costa Rican ecotourism. While the history of the Preserve is somewhat unique, the analysis of visitation, financial, ecological and economic factors provides a convincing case that tourism at the Preserve is sustainable. The experience of the Preserve is also put in the context of Costa Rican ecotourism, particularly to the national parks. The paper concludes that the Preserve has played a very important role in the development of Costa Rica as an ecotourism destination. Nonetheless, the failure of experience at the Preserve to inform recent changes in national park pricing policy reveal that Costa Rica has yet to fully capitalize on the experience gained and lessons learned at the Preserve.     

Tropical Rain Forest Structure,Tree Growth and Dynamics along a 2700-m Elevational Transect in Costa Rica

Rapid biological changes are expected to occur on tropical elevational gradients as species migrate upslope or go extinct in the face of global warming. We established a series of 9 1-ha plots in old-growth tropical rainforest in Costa Rica along a 2700 m relief elevational gradient to carry out long-term monitoring of tropical rain forest structure, dynamics and tree growth. Within each plot we mapped, identified, and annually measured diameter for all woody individuals with stem diameters >10 cm for periods of 3-10 years. Wood species diversity peaked at 400-600 m and decreased substantially at higher elevations. Basal area and stem number varied by less than two-fold, with the exception of the 2800 m cloud forest summit, where basal area and stem number were approximately double that of lower sites. Canopy gaps extending to the forest floor accounted for <3% of microsites at all elevations. Height of highest crowns and the coefficient of variation of crown height both decreased with increasing elevation. Rates of turnover of individuals and of stand basal area decreased with elevation, but rates of diameter growth and stand basal area showed no simple relation to elevation. We discuss issues encountered in the design and implementation of this network of plots, including biased sampling, missing key meteorological and biomass data, and strategies for improving species-level research. Taking full advantage of the major research potential of tropical forest elevational transects will require sustaining and extending ground based studies, incorporation of new remotely-sensed data and data-acquisition platforms, and new funding models to support decadal research on these rapidly-changing systems.     

The Landscape Ecology of Tropical Secondary Forest in Montane Costa Rica

Multinomial logistic models of land use/land cover in montane Costa Rica and landscape pattern analysis showed that relative to agriculture, secondary forest occurred closer to old-growth forest, further from roads, in forest reserves, and at higher elevations. Collinearity between explanatory variables yielded simple multivariate models; proportion of surrounding old growth predicted secondary forest most accurately. An old-growth matrix [mean patch size (MPS) 24.5 ha], located mainly within protected areas, dominated elevations greater than 2500 m. A matrix of agriculture (MPS 23.5 ha), with smaller patches (approximately 9 ha) of secondary forest and old growth, dominated elevations from 1500 to 2500 m. Combining secondary forest with old growth decreased forest patch number and increased MPS from 7.3 to 37.1 ha. I concluded that: (a) secondary forest pattern is nonrandom, so ancillary data will aid its mapping with satellite imagery. The variables elevation, agriculture distance, road distance, and population density distinguished secondary forest from old growth with 74% accuracy; (b) socioeconomic and biological forces probably interact to create these secondary forest patterns; and (c) the strong association between secondary forest and old growth supports the concept that tropical forest recovery depends on the landscape structure of remnant forest. Received 16 February 1999; accepted 20 August 1999.     

Microhabitat distribution of protostelids in a Tropical Wet Forest in Costa Rica

A microhabitat study of protostelids was carried out in a Tropical Wet Forest at the La Selva Biological Station in Costa Rica. Nine species were recorded from sterile wheat straws placed out and then re-collected over a period of six weeks from two different litter microhabitats in an area of primary forest. All nine species were present on straws placed in the aerial litter microhabitat, but only six species were present on straws placed in the forest floor litter microhabitat. Total colonies, percent of straws colonized, and mean number of species per straw increased significantly over time. One species (Schizoplasmodiopsis pseudoendospora) typical of temperate litter was the overwhelming dominant on the forest floor litter, while Echinostelium bisporum, a species rare in temperate litter microhabitats, was the single most abundant species in the aerial litter microhabitat. Both of these species had significantly increased frequencies over time. Two species abundant in temperate aerial litter microhabitats and one species abundant in temperate forest floor litter were rare at La Selva. Our data conform to those obtained in an earlier study carried out in tropical forests in the mountains of Puerto Rico and provide additional support towards developing a model of microhabitat distribution of protostelids in terrestrial ecosystems.     

Early Tree Diversity and Composition Effects on Topsoil Chemistry in Young Forest Plantations Depend on Site Context

Ecosystems - Trees have a strong influence on the chemical properties of the soil in which they grow. Establishing plantations with different tree species combinations thus potentially leads to...     

Box-Jenkins analysis for shark landings in Costa Rica

Sharks are highly vulnerable to intense and prolonged fishery extraction. This article analyzes the data on shark landings from the artisan fishing fleet on Costa Rica's Pacific coast between 1988 and 1997. The data come from an invoicing system administered by the Costa Rican Fisheries Institute (Instituto Costarricense de la Pesca y Acuacultura, INCOPESCA). Pacific coast shark fishing during the period under study represented approximately 20% of the total national fisheries volume. According to data from the invoicing system, the Northern Pacific region was the most productive, reporting 58% of the shark catch nationwide. Within this region, shark fishing in Papagayo Gulf represented 91% and 53% of the landings by fishery region and nationwide, respectively. The mid-sized and advanced (length of boat > 10 meters) artisan fishing fleets reported 96% of the shark catches in the zone. The study of shark fisheries in the Papagayo Gulf zone is crucial for an understanding of fishery dynamics for this resource at the national level. A monthly chronological series was constructed with the landings in the Papagayo Gulf zone, and a Univariate Box-Jenkins (UBJ) Model was estimated for first-order moving averages MA(1) with a seasonal component of the Yt = lamda(t-1) + gammaS12 + a(t) type.     

The Influence of Habitat Variables on Bird Communities in Forest Remnants in Costa Rica

This study examined the effects of forest structure (tree species richness, canopy height, percent canopy cover, understory density, tree density and DBH) and avian species traits (nest type and indicator list status) on the diversity, abundance and dissimilarity of bird communities in forest remnants and reforestation areas adjacent to Costa Rican banana plantations. Bird species richness and abundance were significantly related to tree species richness, canopy height and canopy cover in multiple linear regressions, the latter two forest structure variables being the best statistical predictors. Stratification of analyses by bird species indicator categories improved fits of regressions, because correlations with environmental variables differed in sign for different guilds of birds, a result likely to hold for other avifaunas. Analysis of avifauna dissimilarities among sites demonstrated that the species composition of bird communities was highly correlated with forest structure and tree species composition. Logistic regressions indicated that birds making protected (cavity, burrow, pendant, sphere and covered) nests were 2–6 times more likely to be present in the study avifauna than birds making open (cup, saucer, platform and scrape) nests and indicators of disturbed habitats were 11 times more likely to be present than indicators of primary forest. The forest structure data used were simple and inexpensive to collect, and data on avian traits were drawn from the literature. Thus, these methods could easily be replicated at other locations and would be valuable management aids and biodiversity assessment tools for conservation planning.     

Forest Regeneration in a Chronosequence of Tropical Abandoned Pastures: Implications for Restoration Ecology

During the mid‐1900s, most of the island of Puerto Rico was deforested, but a shift in the economy from agriculture to small industry beginning in the 1950s resulted in the abandonment of agricultural lands and recovery of secondary forest. This unique history provides an excellent opportunity to study secondary forest succession and suggest strategies for tropical forest restoration. To determine the pattern of secondary succession, we describe the woody vegetation in 71 abandoned pastures and forest sites in four regions of Puerto Rico. The density, basal area, aboveground biomass, and species richness of the secondary forest sites were similar to those of the old growth forest sites (>80 yr) after approximately 40 years. The dominant species that colonized recently abandoned pastures occurred over a broad elevational range and are widespread in the neotropics. The species richness of Puerto Rican secondary forests recovered rapidly, but the species composition was quite different in comparison with old growth forest sites, suggesting that enrichment planting will be necessary to restore the original composition. Exotic species were some of the most abundant species in the secondary forest, but their long‐term impact depended on life history characteristics of each species. These data demonstrate that one restoration strategy for tropical forest in abandoned pastures is simply to protect the areas from fire, and allow natural regeneration to produce secondary forest. This strategy will be most effective if remnant forest (i.e., seed sources) still exist in the landscape and soils have not been highly degraded. Patterns of forest recovery also suggest strategies for accelerating natural recovery by planting a suite of generalist species that are common in recently abandoned pastures in Puerto Rico and throughout much of the neotropics.     

Peasants against Globalization: Rural Social Movements in Costa Rica

Peasants against Globalization: Rural Social Movements in Costa Rica. Marc Edelman. Stanford: Stanford University Press, 1999. 308 pp.     

Familial breast cancer in Costa Rica: an initial approach

Cancer is a worldwide problem because of its high rates of incidence and associated mortality. By 2000, more than 6.2 million people died from this illness worldwide. Among all types of cancer, breast cancer is one of the most studied. Each year, one million new cases are diagnosed around the world. We can classify breast cancer into two main kinds: sporadic cases and those which are a product of inherited genetic alterations. Approximately 5-10% of breast cancer cases are the result of inherited mutations, or alterations in breast cancer susceptibility genes, BRCA1 and BRCA2. Like other countries, Costa Rica possesses high rates of incidence and mortality for breast cancer. According to the "Registro Nacional de Tumores" (National Office of Tumor Records), in 2000 breast cancer had the highest rate of incidence and in 2002 it had the highest rate of mortality in comparison to other types of cancer. For this reason and the generalized lack of knowledge in the field we conducted an epidemiological research on breast cancer patients from Hospital San Juan de Dios, San José, Costa Rica, to find families with a history of breast cancer, and to determine the occurrence of familial cases within the population studied. So far, we have found 23 families, within which we discovered very informative cases that have rendered the identification of a pattern of inheritance. These findings allow us to announce that in Costa Rica there are several cases of inherited breast cancer and that we need more research is needed to improve the prevention, control, and treatment of this disease.     

Equine pythiosis in Costa Rica: Report of 39 cases

Thirty-nine pythiosis equine cases, were studied at the Veterinary Medicine School of the National University of Costa Rica, between 1981 and 1984. Lesions were located in different parts of their anatomy: anterior and posterior extremities, abdomen, thorax, breast and mammary gland, and were characterized by their tumoral appearance with necrotic tissue in which yellow-white coral-like necrotic masses, called kunker or leeches were shown. Splendore-Hoeppli like phenomenon and eosinophilic inflammatory reaction aroud the hyphae, was microscopically observed. Pythium sp. (Hyphomyces destruens) was isolated in Sabouraud dextrose agar from ground kunkers. Immunodiffusion (ID) to diagnose this disease in equines, was performed with succes. Immunotherapy was applied to 5 of affected horses, and three were cured. Some epizootiological aspects of the the pythiosis are also discussed.     

Centruroides Schmidti (scorpiones: Buthidae) in Costa Rica

Centruroides schmidti Sissom, 1995 is the new identification designate of the scorpions previously known as C. thorelli (Kraepelin, 1891) in Northwest Costa Rica. The geographical distribution of the species in this country is established on the basis of new collected material. Its distribution includes the Pacific slope of the Guanacaste volcanic range, and the Pacific and Atlantic slopes of the Tilarán volcanic range between 50 and 775 m elevation above sea level, within the Costa Rican Guanacaste and Alajuela provinces.     

Large-scale Ecological Restoration of Degraded Tropical Forest Lands: The Potential Role of Timber Plantations

Large areas of the world's tropical forests are being degraded, with a consequent loss of species diversity. Only some of these are able to recover unaided. Where attempts are being made to restore such forests, the scale of the attempts is usually small. Timber plantations are one of the few means by which large areas of cleared or degraded landscape can be reforested. These usually restore the productive capacity of the landscape but do little to recover biological diversity. But a number of approaches might be used to redesign such plantations so that they would both yield the timber needed to justify the investment and also contain some proportion of their former biodiversity. These approaches include using indigenous species rather than exotic species, creating species mosaics by matching species to particular sites, embedding the plantation monocultures in a matrix of intact or restored vegetation, using species mixtures rather than monocultures, or encouraging the diverse plant understories that can often develop beneath plantations. The degree of ecological restoration possible using these alternatives ranges from modest to significant, although none is likely to achieve complete restoration. Any improvements in regional biodiversity brought about by these changes might be seen as being at the expense of plantation productivity. But many of these approaches have advantages other than just restoring former biodiversity. I discuss some of the trade-offs and implications for plantation managers and restorationists.     

Current Loads of Coarse Woody Debris on Southeastern Australian Floodplains: Evaluation of Change and Implications for Restoration

We evaluated the status of coarse woody debris (CWD, fallen wood) on floodplains of the southern Murray‐Darling basin of southeastern Australia. The floodplains are dominated floristically by the river red gum Eucalyptus camaldulensis. Aerial survey techniques were used to estimate the amounts of woody debris within 200 m of the channels along 2,442 km of 11 rivers of the system, including the Murray and Darling Rivers and the Darling Anabranch. Aerially based indices were converted into wood volumes by using ground‐truthing at a selection of sites; there was a strong correlation between index values and measured wood volume densities. For thickly forested sites such as Barmah, Gunbower Island, and the Ovens floodplains, the aerial method was not useful, so ground measurements at randomly positioned sites within the forests were used. Volumes were translated into mass by using conversion factors drawn from the literature. We estimated that total tonnage on approximately 221,000 ha of floodplain forests was 4.175 ± 0.579 × 10⁶ tonne. In the larger forested blocks (>7,000 ha), mean wood densities ranged between approximately 12 tonne/ha on the lower Goulburn up to approximately 24 tonne/ha at Barmah State Forest. The area‐weighted mean for the entire area was approximately 19 tonne/ha. A main purpose of the research was to place these figures into an historical perspective to evaluate implications for restoration. A thorough search of historical documentation revealed that there are no extant data upon which to estimate pre‐European settlement levels. We used information from an apparently undisturbed “unmanaged” site in the Millewa forests of southern New South Wales as a basis. Wood density there corresponded to a mean figure of 125 tonne/ha wood‐mass density. By using this figure we estimate that CWD levels on the southern Murray‐Darling basin may be of the order of 15% of pre‐European settlement levels. Full restoration of the 221,000 ha surveyed would require 23.5 ± 0.579 × 10⁶ tonne, which is equivalent to about 600,000 mature (1 m diameter at breast height) river red gum trees or the amount of timber derived from clear felling about 115,000 ha of river red gum forest at current stocking levels. We discuss the implications of this massive deficit and possible short‐ and long‐term solutions.     

Gringos En El Bosque: Introduced Tree Invasion in a Native Nothofagus/Austrocedrus Forest

We studied invasion into native Nothofagus/Austrocedrus forest by many introduced tree species planted between 1910 and 1940 in plantations near the center of Isla Victoria, in northern Patagonia. We located virtually all individuals of these species in 30 ha of forest in two series of transects at increasing distances from the plantations. Although these species included many reported as highly invasive elsewhere, we found little evidence for invasion on Isla Victoria, with many invasive species utterly failing to invade native forest. There was a notable decline with distance in number of introduced individuals, but wind direction appeared to be unimportant. Pseudotsuga menziesii and Juniperus communis were the only 2 species represented by many individuals, while 4 pine species plus Araucaria araucana were far less numerous and 6 other species were found fewer than 10 times each. Even those species found repeatedly were represented overwhelmingly by small individuals, and the great majority of introduced individuals were found not in native forest proper, but in somewhat open areas such as road verges, small remnant pastures, and deer trails. Invasion may be occurring, but too slowly to be clearly evidenced yet because of the longevity of the dominant native trees. Factors that may be stopping or slowing invasion include competition in gaps with native species, browsing by introduced deer, unfavorable soil, allelopathy, and natural enemies or other idiosyncratic factors for particular species. The absence of substantial invasion so far is no guarantee against future invasion, particularly if some major natural or anthropogenous disturbance were to occur.     

Understanding Smallholder Participation in Payments for Ecosystem Services: the Case of Costa Rica

This paper uses household survey data to examine factors associated with smallholder households that enroll in Costa Rica’s longstanding payments for ecosystem services (PES) program. To date, most evaluations of this sort have focused on larger landowners. Results from this study show that smallholders enrolled in PES tend to be older, wealthier, and have access to non-farm salaried income. These features match enrollment patterns of larger landowners in that enrollees tend to be relatively wealthy and only marginally engaged in agriculture. In addition, smallholders on state agrarian reform lands are significantly less likely to enroll in PES. These results indicate that targeting PES toward smaller landowners does not necessarily equate to a policy that reaches the rural poor, and suggests that further work is needed to address the access barriers to this program for economically marginal landowners.