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BOX 5The Relationship between Forest Cover and WildlifeStudies have shown that logging in tropical forests can change the composition of wildlife in direct proportion to forestdisturbance. 1 Selective logging and subsequent silvicultural techniques (e.g., enrichment strip planting) can result in adramatic change in forest condition, reducing the presence of those animal species dependent on primary habitats. Forexample, an investigation of understory birds in Venezuela found that of the twenty-two bird species occurring in primaryforest, two increased in number after selective logging but sixteen declined and four were no longer recorded. Thecreation of enrichment strips changed the composition even more. 2For some species of small tropical mammals (e.g. bats, small rodents, and marsupials), logging provides several benefits,including more food resources provided by pioneer plants, fungi, and invertebrates on the forest floor and more roostingcavities associated with fallen trees. 3 However, logging is usually only beneficial to a relatively small number of species,and the loss of other sensitive species may have ecological consequences. Many wildlife species affected by logging providefundamental services and regulate key ecological processes in forest ecosystems (e.g., pollination, dispersion ofseeds and micorrhiza, regeneration of degraded areas, and control of insect populations). Their absence in logged foreststherefore can also have negative impacts on plant population dynamics. Furthermore, declines in the population of someanimals (or even local extinction) can have repercussions on the survival of their predators as well.Changes in bat communities have been observed in logged areas of the Venezuelan Guayana region. Figure below showsthe relationship between the absolute numbers of individuals and the number of different species under three scenarios:primary forests, selective logging, and selective logging with enrichment strips. Note that the curve for enrichment stripshas the lowest level for both numbers of individuals and numbers of species, with only three species representingapproximately 65 percent of individuals. A similar pattern was found in logged forests without enrichment strips (70percent of individuals represented by only five species), even though the abundance of individuals and species richnesswas higher. The reduced diversity in intensively logged areas may have negative impacts on the regenerative capacity ofthe forest and its potential for wood production. For example, commercially valuable trees such as Pachira quinata(saqui saqui) and Ceiba pentandra (ceiba) depend on particular bat species for pollination.Effects of Logging on Bat Populations in the Guayana RegionSource: Copyrighted 2000 by the Association for Tropical Biology, PO Box 1897, Lawrence, KS 66044-8897. Reprinted by permission.Notes:1. F.E. Putz et al., “Biodiversity conservation in the context of tropical forest management,” The World Bank Environment Department Papers,Biodiversity Series-Impacts Studies (Washington, DC: World Bank , ), 75: 1-80; J.M. Thiollay, “Influence of selective logging on bird speciesdiversity in a Guianan rain forest,” Conservation Biology vol. 6: 47-63 (1992); D.J. Mason, “Responses of Venezuelan understory birds toselective logging, enrichment strips, and vine cutting.” Biotropica vol. 28: 296-309 (1996); J. Ochoa G., “Efectos de la extracción de maderassobre la diversidad de pequeños mamíferos en bosques de tierras bajas de la Guayana Venezolana,” Biotropica vol 32: 146-164 (2000).2. D.J. Mason, op.cit.3. P. Charles-Dominique, “Inter-relations between frugivorous vertebrates and pioneer plants: Cecropia, birds, and bats in French Guyana,” inA. Estrada y T. H. Fleming (Eds.), Frugivores and seed dispersal, pp. 119-135. (Dordrecht, Holand: Dr W. Junk Publishers, 1986); J. Kikkawaand P.D. Dwyer, “Use of scattered resources in rain forest of humid tropical lowlands,” Biotropica vol. 24: 293-308 (1992); J. Ochoa G.,“Efectos de la extracción de maderas sobre la diversidad de pequeños mamíferos en bosques de tierras bajas de la Guayana Venezolana,”Biotropica vol 32: 146-164 (2000); A.D. Johns, “Effects of ‘Selective’ Timber Extraction on Rain Forest Structure and Composition and SomeConsequences for Frugivores and Folivores,” Biotropica vol.20: 31-37 (1988).28
Threatened and Endemic Species by Sub-Region of GuayanaMAP 7These are schematic sub-regions based on general geographic and administrative zones. For source information, see Annex 1.*According to the Geneva Agreement of February 7, 1966, Venezuela claims two-thirds of the territory of Guyana.29
Page 2 and 3: The State of Venezuela’s ForestsA
Page 5: PresentationMan has become increasi
Page 9 and 10: ForewordForests help to slow global
Page 11 and 12: AcknowledgmentsGlobal Forest Watch
Page 13 and 14: Mining ............................
Page 15 and 16: 6. Actual and Potential Conflicts B
Page 18 and 19: Key FindingsVenezuela is still home
Page 20 and 21: However, the forests of the Guayana
Page 22 and 23: 2Political and Administrative Bound
Page 24: MAP 2Settlements in the Forests of
Page 27 and 28: In 1998, the Venezuelan Forest Serv
Page 29 and 30: Legal Instrument Year RelevanceDecr
Page 31 and 32: CHAPTER 2Forest Cover and Protectio
Page 33 and 34: 13Forest CoverMAP 3Data on forest c
Page 35 and 36: • Lack of consistency in results.
Page 37 and 38: 17Areas Strictly Protected for Cons
Page 39 and 40: Areas protected for natural resourc
Page 41 and 42: Actual and Potential Conflicts Betw
Page 43 and 44: Capacity to Manage Protected Areas
Page 45 and 46: CHAPTER 3Non-Extractive Value of Fo
Page 47: Wildlife Species Richness in the Gu
Page 51 and 52: At least thirteen plants and animal
Page 53 and 54: The capture and collection of parro
Page 55 and 56: CHAPTER 4Forest Development TrendsV
Page 57 and 58: Imports, Exports, and National Prod
Page 59 and 60: Industrial Wood Production, 1980-19
Page 61 and 62: • In 1997, royalties and fees com
Page 63 and 64: Status of Logging Concessions in th
Page 65 and 66: Irregularities in Logging Concessio
Page 67 and 68: Low extraction rates in the Guayana
Page 69 and 70: The Guayana region lacks a transpar
Page 71 and 72: The capacity for regeneration of co
Page 73 and 74: MiningWhat is the relative importan
Page 75 and 76: Venezuelan Gold and Diamond Product
Page 77 and 78: • Concession owners are required
Page 79 and 80: Foreign Mining Companies with Holdi
Page 81 and 82: By nature, mining is a speculative
Page 83 and 84: signs of contamination, 97 and anot
Page 85 and 86: SettlementsHow are settlement patte
Page 87 and 88: What is the impact of population ch
Page 89 and 90: y these actors. In addition, becaus
Page 91 and 92: CHAPTER 5ConclusionsGlobal Forest W
Page 93 and 94: Providing Better Information for In
Page 95 and 96: 18 Ministerio del Ambiente y de los
Page 97 and 98: 37 MARN, Boletín Estadístico Fore
Page 99 and 100:
62 R. Posada, “Algunos aspectos s
Page 101 and 102:
83 Government of Venezuela (GOV), D
Page 103 and 104:
103 Legislation does not define sta
Page 105 and 106:
Methodology:• Data on the locatio
Page 107 and 108:
• TREES from ATSR onboard the ERS
Page 109 and 110:
Maps 4-6, Figures 2-4Venezuela’s
Page 111 and 112:
• There are differences between t
Page 113 and 114:
Wildlife Restricted to Forests of t
Page 115 and 116:
Threatened Animals Used by Indigeno
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Chapter 4: Forest Development Trend
Page 119 and 120:
Note: There are many inconsistencie
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Annual Cutting Plans (Executed)Area
Page 123 and 124:
Management Area (ha) Contract Years
Page 125 and 126:
Table Sources:• Concession manage
Page 127 and 128:
Price of Gold, 1975-2000 (Figure 20
Page 129 and 130:
Methodology (Figure 23, Table 11, M
Page 131 and 132:
Change in Selected Indigenous Popul
Page 133 and 134:
iar with forest issues in Venezuela
Page 135 and 136:
Gydris Adrián Comisión Especial p
Page 137 and 138:
Ortegano, O. “Nueva Política For
Page 139 and 140:
Chapter 3: Non-timber Forest Produc
Page 141 and 142:
Dessene, P., and S. Strhal. “Situ
Page 143 and 144:
Hernández, L., P. Williams, R. Azu
Page 145 and 146:
Ojasti, J. “Fauna silvestre del e
Page 147 and 148:
Técnica Minera C.A. Inventario de
Page 149 and 150:
Nepstad, D., et al. “Large-scale
Page 151 and 152:
Government Industry Task Force on t
Page 153 and 154:
All data presented in this report a
Page 155:
GLOBAL FOREST WATCH (GFW)WORLD RESO
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