Rapid Biodiversity Assessment of Halcrow
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E1751 RAPID BIODIVERSITY ASSESSMENT OF HALCROW AND GUYSUCO CONSERVANCIES Public Disclosure Authorized Public Disclosure Authorized Public Disclosure Authorized FINAL R EPORT Example: Densely populated JANUARY 2006 wooded reefs of low-medium height Photo: W. Prince Environmental Management Consultants Public Disclosure Authorized 60 Area H Ogle East Coast Demerara Cover photos: Waldyke Prince and Dr. Gary Clarke Top: Yellow Oriole Icterus nigrogularis Spectacled Caiman Caiman crocodilus Mabuya Skink Mabuya mabuya White Leaf Frog Hyla leucophyllata Bottom: Aerial view of the Skeldon Water Path bordering the Guysuco Conservancy Page 2 of 47 CONTENTS PAGES Executive Summary 6 1. INTRODUCTION 8 2. METHODOLOGY 2.1 Study Site 9 2.2 Schedule of Fieldwork 9 2.3 Vegetation Surveys 9 2.4 Faunal Surveys 11 2.5 Sampling Protocol 12 2.6 Collection of specimens 12 2.7 Photography 13 2.8 Data Analysis 13 3. RESULTS & DISCUSSION 3.1 Vegetation 14 3.2 Invertebrate fauna 19 3.3 Fish Fauna 20 3.4 Amphibian Fauna 21 3.5 Reptile Fauna 23 3.6 Mammal Fauna 24 3.7 Avifauna 26 3.8 Key Species and Habitats of Conservation Importance 32 3.9 Indicator Species 32 3.10 Summary of Flora and Fauna Species Diversity 32 3.11 Shift in Species Composition 33 4. CONSTRAINTS & LIMITATIONS 34 5. MANAGEMENT RECOMMENDATIONS 5.1 Biodiversity monitoring 35 5.2 Hunting 35 5.3 Cattle Ranching 35 5.4 Fire Control 35 5.5 Management of Watershed/Catchment Area 35 6. LITERATURE CITED 36 APPENDIX I Terms of Reference 37 APPENDIX II Schedule of Activities and Fieldwork 39 APPENDIX III Avifauna Transect Monitoring Datasheet 40 APPENDIX IV Images 42 Page 3 of 47 Table 1. Composition of Assessment Team, Team Member Expertise and Roles 9 Table 2. Geographical location of transects 11 Table 3. List of Flora Species recorded in the Halcrow and GUYSUCO Conservancies 14 Table 4. Frequency of Woody Species above 5cm dbh in all Halcrow Conservancy Transects 16 Table 5. Frequency of Woody Plant Species frequency in Halcrow Conservancy Transects 16 Table 6. Understorey Species < 5cm dbh occurring in each quadrat in the Halcrow Conservancy 17 Table 7. Frequency of Woody Plant Species in the GUYSUCO Conservancy Transect 18 Table 8. Understorey Species < 5cm dbh occurring in each quadrat in the GUYSUCO Conservancy 19 Table 9. Invertebrate Fauna of the Conservancies 19 Table 10. Fish Species Diversity and Abundance in the Skeldon Water Path and surrounding Waterways 20 Table 11. Amphibian Species Diversity and Abundance in the GUYSUCO and Halcrow Conservancies 22 Table 12. Reptile Species Diversity and Abundance in the GUYSUCO and Halcrow Conservancies 23 Table 13. Mammal species diversity and abundance recorded during transect surveys, time searches and opportunistic observations in the GUYSUCO and Halcrow conservancies 25 Table 14. Bat Species Diversity and Abundance in the GUYSUCO and Halcrow Conservancies 26 Table 15. Avifauna Species Diversity and Abundance in the GUYSUCO and Halcrow Conservancies 26 Page 4 of 47 ACRONYMS GUYSUCO Guyana Sugar Corporation EMC Environmental Management Consultants GPS Global Positioning System CITES Convention on International Trade in Endangered Species IUCN International Union for the Conservation of Nature NTFP Non-Timber Forest Species Page 5 of 47 EXECUTIVE SUMMARY The Guyana Sugar Corporation has agreed to manage the Halcrow and GUYSUCO conservancies, Skeldon Estate, to secure the water supply needed for a new sugar factory and expanded cane cultivation and also to conserve the biological diversity of the conservancies. A biodiversity assessment team was contracted to survey the flora and fauna within the Halcrow and GUYSUCO conservancies, collect baseline data on the presence, distribution and relative abundance of species, and take special note of key species and habitats of conservation interest. In total the assessment team conducted 17 days of fieldwork from 14th to 30th November 2005. Three broad vegetation types were found to exist in the conservancies, with one intermediate type: 1) densely populated wooded reefs of low-medium height, 2) low-grass savannah, 3) papyrus-dominated wet savannah, and 4) sparsely wooded savannah with isolated trees and/or tree islands (intermediate). In total 56 plant species were recorded. Vegetation types and plant species assemblages were similar between the two conservancies. Within each of the vegetation types species assemblages were fairly homogenous and were typical of secondary or disturbed wet marsh habitats. The vegetation is disturbed due to the area historically and currently being used as cattle pasture. Also there is evidence that the grassland (and forest) is subject to burning in the dry season either naturally or by man. No plant species of national or regional significance or global conservation importance were found. In total 481 fish belonging to 20 species and 9 families were recorded. Perch-like fishes (perciformes) and characids (characiformes) dominated the fish fauna. The main species caught by local fishermen to sell for human consumption (of economic importance) were the hassa Hoplosternum littorale, common pattwa Cichlasoma bimaculatum, and the huri Hoplias marabalicus. In total 113 amphibians belonging to 10 species and three families were recorded: one toad species (Bufonidae), six species of tree frogs (Hylidae), and three species of rain frogs (Leptodactylidae). The ubiquitous cane toad Bufo marinus dominated the amphibian community. In total 69 reptiles belonging to 12 species and seven families were recorded: one caiman species, six lizard species, four snake species and one tortoise species. Spectacled caiman Caiman crocodiles, the giant ameiva Ameiva ameiva, and the common tegu Tupinambis teguixin dominated the reptile community. In total 93 volant and non-volant mammals belonging to 13 species were recorded. Sixty non-volant mammals belonging to eight species and six families were recorded. The most commonly observed non- volant mammals were the squirrel monkey Saimiri scuireus and red rumped agouti Dasyprocta leporina. Five bats species were recorded during surveys and mist netting, one emballonurid, the proboscis bat Rhynconycteris naso, and four phyllostomid species (leaf-nosed bats) bats, which were captured in mist nets. In total 2797 birds belonging to 119 species and 38 families were recorded and we estimate that the true species richness for the avifauna is around 140 species. The smooth billed ani Crotophaga ani, brown- throated parakeet Aratinga pertinax and the great kiskadee Pitangus sulpharatus dominated the avifauna community. All of the faunal species recorded have a wide geographical distribution, are relatively common, and are tolerant of a wide range of habitats, including disturbed habitats. Plant species in the conservancies also have a wide geographical distribution and are not uncommon in Guyana. Only three animal species of conservation importance were recorded. The yellow-footed tortoise Geochelone denticulata is listed by IUCN as Vulnerable and in the region it is harvested at an unsustainable rate for human consumption. We observed signs indicating the presence of jaguar Panthera onca, a species listed as Near Threatened by IUCN. Finally, we recorded the blue-cheeked amazon parrot Page 6 of 47 Amazona dufresnia, which is listed by IUCN as Near Threatened. The assessment team surveyed the area for West Indian manatee Trichechus manatus, listed by IUCN as Vulnerable, and interviewed local people. No manatees were observed and local’s state that they have not been seen for many years and are likely to have been extirpated (hunted out) from the area. In this report a number of recommendations are made as to how the conservancies could be managed to conserve biodiversity, including the need for biodiversity monitoring. It is suggested that birds be used as indicator species for biodiversity monitoring as they are ecologically diverse, relatively common in the conservancies, well studied, relatively easy to sample and identify, and able to respond rapidly to environmental changes. Page 7 of 47 1. INTRODUCTION The Guyana Sugar Corporation (GUYSUCO) is building a larger, modern sugar factory at Skeldon, Corentyne Berbice, Guyana. Sugar cane cultivation will be expanded to supply the capacity of the new factory. The new factory and expanded sugar cane cultivation will require a constant supply of fresh water. Therefore GUYSUCO has agreed to manage two adjacent conservancies, which are state lands under long-term management by GUYSUCO, to secure the water supply needed and conserve biodiversity. Dams are being built around the conservancies that will lead to an increase in water level within the conservancies and the creation of a mini-reservoir with a total surface area estimated to be approximately 1520ha and a maximum depth of 1m (Anon. 2002). The mini-reservoir will thus cover the entire 1400 ha of the GUYSUCO conservancy and small fraction of the Halcrow conservancy, approximately 120ha of 6000ha (2%). Water will be drawn from these conservancies to irrigate new areas under sugar cane cultivation. In order to manage the conservancies for biodiversity conservation there is a need to document the flora and fauna. EMC was contracted to conduct a Rapid Biological Assessment (RBA) of both Halcrow and GUYSUCO conservancies (Appendix I). The EMC biodiversity assessment team surveyed the flora and fauna within habitat types encompassed by both conservancies, collecting baseline data on the presence, distribution and relative abundance of species and taking