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Coral Reefs and Their Management in Tanzania
G M Wagner
Western Indian Ocean Journal of Marine Science , 2004,
Abstract: Coral reefs are very important in Tanzania, both ecologically and socio-economically, as major fishing grounds and tourist attractions. Numerous fringing and patch reefs are located along about two-thirds of Tanzania's coastline. These reefs have been partially to severely degraded by human (primarily destructive fishing practices) and natural (particularly coral bleaching) causes. These immediate human causes have been brought about by various socioeconomic root causes, particularly poverty and lack of proper management. After decades of human and natural impacts there has been only limited reef recovery. This paper presents a region-by-region analysis of trends in the condition of coral reefs in Tanzania in relation to the causes of damage. While earlier approaches to management were aimed at non-use of coral reefs in marine protected areas (seldom achieved), recent approaches have aimed at integrated coastal management (ICM) (whether in programs or conservation areas), where zonation into core protected areas and multiple-use areas is based on participatory decision-making involving fishing communities and other stakeholders. Some management initiatives also involve communities in reef monitoring, restoration and ecotourism. This paper examines the management approaches and strategies implemented by various ICM programs, conservation areas and marine parks in Tanzania. It also provides recommendations for further research and coral reef management strategies.
SIMAC: Development and implementation of a coral reef monitoring network in Colombia
Garzón-Ferreira,Jaime; Rodríguez-Ramírez,Alberto;
Revista de Biología Tropical , 2010,
Abstract: significant coral reef decline has been observed in colombia during the last three decades. however, due to the lack of monitoring activities, most of the information about health and changes was fragmentary or inadequate. to develop an expanded nation-wide reef-monitoring program, in 1998 invemar (instituto de investigaciones marinas y costeras: "colombian institute of marine and coastal research") designed and implemented simac (sistema nacional de monitoreo de arrecifes coralinos en colombia: "national monitoring system of coral reefs in colombia") with the participation of other institutions. by the end of 2003 the simac network reached more than twice its initial size, covering ten reef areas (seven in the caribbean and three in the pacific), 63 reef sites and 263 permanent transects. simac monitoring continued without interruption until 2008 and should persist in the long-term. the simac has a large database and consists basically of water quality measurements (temperature, salinity, turbidity) and a yearly estimation of benthic reef cover, coral disease prevalence, gorgonian density, abundance of important mobile invertebrates, fish diversity and abundance of important fish species. a methods manual is available in the internet. data and results of simac have been widely circulated through a summary report published annually since 2000 for the colombian environmental agencies and the general public, as well as numerous national and international scientific papers and presentations at meetings. simac information has contributed to support regional and global reef monitoring networks and databases (i.e. caricomp, gcrmn, reefbase). rev. biol. trop. 58 (suppl. 1): 67-80. epub 2010 may 01.
Calibration of Community-based Coral Reef Monitoring Protocols: Tanzanian Case Study
CA Muhando
Western Indian Ocean Journal of Marine Science , 2010,
Abstract: Coral reef monitoring (CRM) has been recognised as an important management tool and has consequently been incorporated in Integrated Coastal Area Management (ICAM) programmes in the Western Indian Ocean (WIO). Community-based coral reef monitoring (CB-CRM), which uses simplified procedures suitable for local conditions, was introduced in Tanzania in 1996. Despite its widespread use, the method has not been calibrated and the validity of merging CB-CRM results with those gained using other techniques has not been determined. In this study, CB-CRM protocols adopted by the Tanga Coastal Zone Conservation and Development Programme (TCZCDP) were tested against SCUBA-based coral reef monitoring (SB-CRM) as practiced by the Institute of Marine Sciences, University of Dar es Salaam. Calibration showed no significant differences in measuring percent cover of live hard corals, sponges, dead corals and substrata (non-biotic cover). However, CB-CRM monitors recorded higher soft coral and lower fleshy algal cover. Larger differences were observed in deeper (>6 m) transects. Counts of sea cucumbers, clams, gastropods and bivalves categories were not significantly different. However, CB-CRM underestimated the abundance of sea urchins, starfish and younger macro-invertebrates in crevices or under overhangs. There were no differences in the identification of reef fish categories but CB-CRM recorded slightly higher reef fish densities than SB-CRM. If properly trained, CB-CRM monitors can generate results that are comparable to those obtained from SB-CRM on shallow reefs. Although a powerful tool which engenders community involvement and a sense of ownership in the sustainable use of coastal resources, CB-CRM has limitations of which managers need to be aware.
Mid-term coral-algal dynamics and conservation status of a Gorgona Island (Tropical Eastern Pacific) coral reef
Zapata,Fernando A; Rodríguez-Ramírez,Alberto; Caro-Zambrano,Carlos; Garzón-Ferreira,Jaime;
Revista de Biología Tropical , 2010,
Abstract: colombian coral reefs, as other reefs worldwide, have deteriorated significantly during the last few decades due to both natural and anthropogenic disturbances. the national monitoring system for coral reefs in colombia (simac) was established in 1998 to provide long-term data bases to assess the changes of colombian coral reefs against perturbations and to identify the factors responsible for their decline or recovery. on the pacific coast, data on coral and algal cover have been collected yearly during seven consecutive years (1998-2004) from 20 permanent transects in two sites at la azufrada reef, gorgona island. overall, coral cover was high (55.1%-65.7%) and algal cover low (28.8%-37.5%) and both exhibited significant changes among years, most notably on shallow areas. differences between sites in both coral and algal cover were present since the study began and may be explained by differences in sedimentation stress derived from soil runoff. differences between depths most likely stem from the effects of low tidal sub-aerial exposures. particularly intense sub-aerial exposures occurred repeatedly during january-march, 2001 and accounted for a decrease in coral and an increase in algal cover on shallow depths observed later that year. additionally, the shallow area on the northern site seems to be negatively affected by the combined effect of sedimentation and low tidal exposure. however, a decrease in coral cover and an increase of algal cover since 2001 on deep areas at both sites remain unexplained. comparisons with previous studies suggest that the reef at la azufrada has been more resilient than other reefs in the tropical eastern pacific (tep), recovering pre-disturbance (1979) levels of coral cover within a 10 year period after the 1982-83 el ni?o, which caused 85% mortality. furthermore, the effects of the 1997-98 el ni?o, indicated by the difference in overall live coral cover between 1998 and 1999, were minor (<6% reduction). despite recurrent natural
The Ecology of ‘Acroporid White Syndrome', a Coral Disease from the Southern Great Barrier Reef  [PDF]
George Roff, E. Charlotte E. Kvennefors, Maoz Fine, Juan Ortiz, Joanne E. Davy, Ove Hoegh-Guldberg
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0026829
Abstract: Outbreaks of coral disease have increased worldwide over the last few decades. Despite this, remarkably little is known about the ecology of disease in the Indo-Pacific Region. Here we report the spatiotemporal dynamics of a coral disease termed ‘Acroporid white syndrome’ observed to affect tabular corals of the genus Acropora on the southern Great Barrier Reef. The syndrome is characterised by rapid tissue loss initiating in the basal margins of colonies, and manifests as a distinct lesion boundary between apparently healthy tissue and exposed white skeleton. Surveys of eight sites around Heron Reef in 2004 revealed a mean prevalence of 8.1±0.9%, affecting the three common species (Acropora cytherea, A. hyacinthus, A. clathrata) and nine other tabular Acropora spp. While all sizes of colonies were affected, white syndrome disproportionately affected larger colonies of tabular Acroporids (>80 cm). The prevalence of white syndrome was strongly related to the abundance of tabular Acroporids within transects, yet the incidence of the syndrome appears unaffected by proximity to other colonies, suggesting that while white syndrome is density dependant, it does not exhibit a strongly aggregated spatial pattern consistent with previous coral disease outbreaks. Acroporid white syndrome was not transmitted by either direct contact in the field or by mucus in aquaria experiments. Monitoring of affected colonies revealed highly variable rates of tissue loss ranging from 0 to 1146 cm?2 week?1, amongst the highest documented for a coral disease. Contrary to previous links between temperature and coral disease, rates of tissue loss in affected colonies increased threefold during the winter months. Given the lack of spatial pattern and non-infectious nature of Acroporid white syndrome, further studies are needed to determine causal factors and longer-term implications of disease outbreaks on the Great Barrier Reef.
SIMAC: Development and implementation of a coral reef monitoring network in Colombia
Jaime Garzón-Ferreira,Alberto Rodríguez-Ramírez
Revista de Biología Tropical , 2010,
Abstract: Significant coral reef decline has been observed in Colombia during the last three decades. However, due to the lack of monitoring activities, most of the information about health and changes was fragmentary or inadequate. To develop an expanded nation-wide reef-monitoring program, in 1998 INVEMAR (Instituto de Investigaciones Marinas y Costeras: "Colombian Institute of Marine and Coastal Research") designed and implemented SIMAC (Sistema Nacional de Monitoreo de Arrecifes Coralinos en Colombia: "National Monitoring System of Coral Reefs in Colombia") with the participation of other institutions. By the end of 2003 the SIMAC network reached more than twice its initial size, covering ten reef areas (seven in the Caribbean and three in the Pacific), 63 reef sites and 263 permanent transects. SIMAC monitoring continued without interruption until 2008 and should persist in the long-term. The SIMAC has a large database and consists basically of water quality measurements (temperature, salinity, turbidity) and a yearly estimation of benthic reef cover, coral disease prevalence, gorgonian density, abundance of important mobile invertebrates, fish diversity and abundance of important fish species. A methods manual is available in the internet. Data and results of SIMAC have been widely circulated through a summary report published annually since 2000 for the Colombian environmental agencies and the general public, as well as numerous national and international scientific papers and presentations at meetings. SIMAC information has contributed to support regional and global reef monitoring networks and databases (i.e. CARICOMP, GCRMN, ReefBase). Rev. Biol. Trop. 58 (Suppl. 1): 67-80. Epub 2010 May 01. En respuesta al proceso de deterioro de los arrecifes coralinos colombianos en las últimas tres décadas, y con el propósito de establecer un sistema de vigilancia para el manejo apropiado de estos valiosos ecosistemas, el Instituto de Investigaciones Marinas y Costeras (INVEMAR) desde 1998 ha impulsando y puesto en marcha el Sistema Nacional de Monitoreo de Arrecies Coralinos en Colombia (SIMAC), con el apoyo de varias instituciones colombianas. El SIMAC ha operado sin interrupción por más de ocho a os, periodo durante el cual se han establecido 63 parcelas permanentes de observación y 267 transectos fijos de evaluación, en diez de las principales áreas geográficas con arrecifes de Colombia (siete en le Caribe y tres en el Pacífico). Los procedimientos metodológicos del SIMAC se hallan descritos detalladamente en el manual de métodos e incluyen: cobertura del bentos
MAPPING OF CORAL REEF ECOSYSTEM IN THE NATUNA ISLANDS USING ALOS IMAGERY  [cached]
Suyarso,Yaya Ihya Ulumuddin,Bayu Prayuda
Journal of Coastal Development , 2011,
Abstract: The coral reef ecology of the Natuna Islands has been studied over 10 years. However, none of those studies produced a coral reef map. Maps of coral reef ecosystem are important for planning, management and monitoring tool. The present study integrates the 115 field data and the ALOS satellite data, using depth invariant index algorithm to generate coral reef ecosystem classes. Those classes are: life corals, dead coral and rubble aggregates, mixing of substrates and sand. The algorithm that composed of three visible bands is applicable at clear water rather than at turbid water environment. Hence, vegetation coverage as well as seagrass, seaweed and macro algae which are in small extent and usually covered by fine sand materials and associated with turbid water, cannot be classified.The aim of this research, which is funded by Critic Coremap – LIPI, is to produce map of coral reef ecosystem in the Natuna Islands.
Mid-term coral-algal dynamics and conservation status of a Gorgona Island (Tropical Eastern Pacific) coral reef
Fernando A Zapata,Alberto Rodríguez-Ramírez,Carlos Caro-Zambrano,Jaime Garzón-Ferreira
Revista de Biología Tropical , 2010,
Abstract: Colombian coral reefs, as other reefs worldwide, have deteriorated significantly during the last few decades due to both natural and anthropogenic disturbances. The National Monitoring System for Coral Reefs in Colombia (SIMAC) was established in 1998 to provide long-term data bases to assess the changes of Colombian coral reefs against perturbations and to identify the factors responsible for their decline or recovery. On the Pacific coast, data on coral and algal cover have been collected yearly during seven consecutive years (1998-2004) from 20 permanent transects in two sites at La Azufrada reef, Gorgona Island. Overall, coral cover was high (55.1%-65.7%) and algal cover low (28.8%-37.5%) and both exhibited significant changes among years, most notably on shallow areas. Differences between sites in both coral and algal cover were present since the study began and may be explained by differences in sedimentation stress derived from soil runoff. Differences between depths most likely stem from the effects of low tidal sub-aerial exposures. Particularly intense sub-aerial exposures occurred repeatedly during January-March, 2001 and accounted for a decrease in coral and an increase in algal cover on shallow depths observed later that year. Additionally, the shallow area on the Northern site seems to be negatively affected by the combined effect of sedimentation and low tidal exposure. However, a decrease in coral cover and an increase of algal cover since 2001 on deep areas at both sites remain unexplained. Comparisons with previous studies suggest that the reef at La Azufrada has been more resilient than other reefs in the Tropical Eastern Pacific (TEP), recovering pre-disturbance (1979) levels of coral cover within a 10 year period after the 1982-83 El Ni o, which caused 85% mortality. Furthermore, the effects of the 1997-98 El Ni o, indicated by the difference in overall live coral cover between 1998 and 1999, were minor (<6% reduction). Despite recurrent natural disturbances, live coral cover in 2004 was as high as that existing before 1982 at La Azufrada, and one of the highest observed on healthy coral reefs in the TEP region. Rev. Biol. Trop. 58 (Suppl. 1): 81-94. Epub 2010 May 01. A través del Sistema Nacional de Monitoreo de Arrecifes Coralinos en Colombia (SIMAC) se han colectado anualmente (1998-2004) datos de cobertura de corales y algas en 20 transectos de 10m localizados en dos profundidades de dos sitios del arrecife de La Azufrada, Isla Gorgona (costa Pacífica). En general, la cobertura coralina fue alta (55.1% - 65.7%) y la de algas baja
Analysis on variation trend of coral reef in Xisha

Dao-Ru Wang,Zhong-Jie Wu,Yuan-Chao Li,Jia-Ri Chen,Min Chen,

生态学报 , 2011,
Abstract: Xisha Islands, located in the northern part of South China Sea, consist of more than 20 islands and atolls. The coral reef of Xisha Islands belongs to the typical ocean distribution of world’s coral reefs, its ecosystem is the most typical in our country and hermatypic coral species are about three-quarters of the total coral species in China. It is addressed with the oldest coral reef community which of the most original and valuable in China. The previous research shows that the islands studded in South China Sea such as Xisha Islands have important influence on the formation of coral reefs along the mainland coast by multiplying and migrating from south to the north. It is supplementary sources of coastal coral larvae in Hainan and Guangdong. Therefore, carrying out the monitoring of coral reef community ecosystem is of great significance to the ecological protection. By the Manta tow and the Line Intercept Transect method, five stations (Xisha Yong xing dao, Shi dao, Xisha zhou, Zhao Shu dao and Bei dao) on Xisha ecological monitoring area were monitored continually from 2005 to 2009. We compared the index changes of Hermatypic coral’s species, coverage and recruitment, and combining with Condition Index, Succession Index, and the variation trend of hard coral in Xisha were analyzed.The results show that, from 2005 to 2009, the coverage of living hermatypic corals in ecological monitoring area is sharply reduced from 68.19% to 7.93%, while the dead coral coverage is sharply increased from 4.70% to 72.90%. Coral recruitment is reduced from 1.18 ind/100 m2 to 0.07 ind/100 m2, hermatypic coral species decreased from 87 to 35. In 2005, the health of coral reefs was very good, and the Condition Index was 1.097. However, the Condition Index cut down to a very low degree in 2009. It was only 0.880. The Succession Index belonged to “very low degree” from 2005 to 2009, and the numerical value was gradually reduce from 0.984 to 1.876.As a whole, hermatypic corals are serious degrade regionally and caused great change to the coral structure and biodiversity, this will lead to a continuous degradation of coral reefs.
Status and conservation of coral reefs in Costa Rica
Cortés,Jorge; Jiménez,Carlos E; Fonseca,Ana C; Alvarado,Juan José;
Revista de Biología Tropical , 2010,
Abstract: costa rica has coral communities and reefs on the caribbean coast and on the pacific along the coast and off-shore islands. the southern section of the caribbean coast has fringing and patch reefs, carbonate banks, and an incipient algal ridge. the pacific coast has coral communities, reefs and isolated coral colonies. coral reefs have been seriously impacted in the last 30 years, mainly by sediments (caribbean coast and some pacific reefs) and by el ni?o warming events (both coasts). monitoring is being carried out at three sites on each coast. both coasts suffered significant reductions in live coral cover in the 1980’s, but coral cover is now increasing in most sites. the government of costa rica is aware of the importance of coral reefs and marine environments in general, and in recent years decrees have been implemented (or are in the process of approval) to protect them, but limited resources endanger their proper management and conservation, including proper outreach to reef users and the general public. rev. biol. trop. 58 (suppl. 1): 33-50. epub 2010 may 01.
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