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• 1. [Article] Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems

  Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such ...

  Citation × Citation Citation Abstract Copy Title: Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems Author: Granek, Elise F. Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such as movement of organisms and particulate matter and ways in which anthropogenic disturbance to interface habitats may affect immediate and adjacent ecosystems. Mangrove forests, a common interface habitat in tropical coastal zones, once lined much of the tropical and subtropical shores worldwide. However, anthropogenic influences on these systems have led to a ~35% reduction in mangrove area over the last fifty years. In light of the perceived importance of mangrove forests as coastal habitat, the rapid decline of this habitat type, and the potential implications of mangrove habitat loss to adjacent ecosystems, it is important to build upon the current state of knowledge for mangrove forests. The chapters in this dissertation report on the following topics. First I review the published literature to examine the available evidence for connections between mangrove forests and coral reefs. I synthesize previous research findings, highlight areas of future research priorities, and propose a conceptual model of how areas of mangrove disturbance and resulting impacts on coral reefs are related. Second, I assess the effects of mangrove clearing on the immediate habitat. I examine how the physical environment changes following mangrove clearing by examining abiotic factors. I also measure changes in algal biomass and diversity to determine what effects physical changes have on the primary producer community. My results indicate that mangrove clearing has dramatic effects on both the physical and biotic environment. Based on measured changes in abiotic and biotic conditions, K. Frasier and I investigate how larval and zooplankton communities differ between intact and cleared mangrove areas. We find that diversity and community composition differ between intact and cleared mangrove areas, highlighting an additional effect of mangrove disturbance with potential implications for adjacent systems. To address the unanswered question of whether and how abiotic and biotic changes in cleared mangrove areas impact adjacent coral reefs, I repeat and expand upon the study I had conducted on abiotic and biotic changes following mangrove removal. The results in the immediate habitat indicate that the effects of mangrove disturbance are broad. Results from the reefs indicate that mangrove disturbance does have effects on adjacent coral reefs. To determine the relative importance of mangrove-derived nutrients to adjacent coral reef ecosystems and to examine how distance from mangroves to reefs and clearing of mangroves affected energy transfer, I sample sessile reef invertebrates. I employ carbon, nitrogen and sulfur stable isotope analysis as a tool to evaluate whether sessile invertebrates: corals, sponges, a bivalve and feather duster worm, utilize mangrovederived nutrients. Though the pattern varies by taxon, this research provides evidence that sessile reef invertebrates utilize mangrove-derived nutrients. Finally, I examine the effect of two consecutive storm events, the 2005 Tropical Storm (later Category 5 Hurricane) Wilma and the subsequent Tropical Storm Gamma, on the coastal zone. The retention rate of field equipment following storm events provides a picture of how coastal protection changes following anthropogenic mangrove disturbance and the implications of continuing mangrove loss as storm frequency and intensity increase in parallel with climate change. These studies provide new evidence on the effects of disturbance to mangroves on coastal and reef systems. Many new research areas are raised by the results presented here. However, these data provide a useful framework for considering conservation and management strategies for mangrove forest – coral reef systems. Title: Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems Author: Granek, Elise F. Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such as movement of organisms and particulate matter and ways in which anthropogenic disturbance to interface habitats may affect immediate and adjacent ecosystems. Mangrove forests, a common interface habitat in tropical coastal zones, once lined much of the tropical and subtropical shores worldwide. However, anthropogenic influences on these systems have led to a ~35% reduction in mangrove area over the last fifty years. In light of the perceived importance of mangrove forests as coastal habitat, the rapid decline of this habitat type, and the potential implications of mangrove habitat loss to adjacent ecosystems, it is important to build upon the current state of knowledge for mangrove forests. The chapters in this dissertation report on the following topics. First I review the published literature to examine the available evidence for connections between mangrove forests and coral reefs. I synthesize previous research findings, highlight areas of future research priorities, and propose a conceptual model of how areas of mangrove disturbance and resulting impacts on coral reefs are related. Second, I assess the effects of mangrove clearing on the immediate habitat. I examine how the physical environment changes following mangrove clearing by examining abiotic factors. I also measure changes in algal biomass and diversity to determine what effects physical changes have on the primary producer community. My results indicate that mangrove clearing has dramatic effects on both the physical and biotic environment. Based on measured changes in abiotic and biotic conditions, K. Frasier and I investigate how larval and zooplankton communities differ between intact and cleared mangrove areas. We find that diversity and community composition differ between intact and cleared mangrove areas, highlighting an additional effect of mangrove disturbance with potential implications for adjacent systems. To address the unanswered question of whether and how abiotic and biotic changes in cleared mangrove areas impact adjacent coral reefs, I repeat and expand upon the study I had conducted on abiotic and biotic changes following mangrove removal. The results in the immediate habitat indicate that the effects of mangrove disturbance are broad. Results from the reefs indicate that mangrove disturbance does have effects on adjacent coral reefs. To determine the relative importance of mangrove-derived nutrients to adjacent coral reef ecosystems and to examine how distance from mangroves to reefs and clearing of mangroves affected energy transfer, I sample sessile reef invertebrates. I employ carbon, nitrogen and sulfur stable isotope analysis as a tool to evaluate whether sessile invertebrates: corals, sponges, a bivalve and feather duster worm, utilize mangrovederived nutrients. Though the pattern varies by taxon, this research provides evidence that sessile reef invertebrates utilize mangrove-derived nutrients. Finally, I examine the effect of two consecutive storm events, the 2005 Tropical Storm (later Category 5 Hurricane) Wilma and the subsequent Tropical Storm Gamma, on the coastal zone. The retention rate of field equipment following storm events provides a picture of how coastal protection changes following anthropogenic mangrove disturbance and the implications of continuing mangrove loss as storm frequency and intensity increase in parallel with climate change. These studies provide new evidence on the effects of disturbance to mangroves on coastal and reef systems. Many new research areas are raised by the results presented here. However, these data provide a useful framework for considering conservation and management strategies for mangrove forest – coral reef systems. Close

• 2. [Article] An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli

  Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, ...

  Citation × Citation Citation Abstract Copy Title: An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli Author: Granek, Elise F. Year: 2000 Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, as part of a project to assess areas for nature reserves which will be able to protect and conserve forest resources in the islands; the bat is postulated to be a useful indicator of undisturbed forest. Known roost sites (n=9) before the survey were between 500 and 1100 m altitude, on steeply sloping land, with some indigenous forest cover present. Thirteen new potential roost sites were identified, of which at least six were confirmed as roost sites for P. livingstonii. Bats showed positive associations with two tree species: Gambeya sp. and Nuxia pseudodentata. The study also investigated the participation by local village communities in monitoring bat populations, and the protection of roost sites. Title: An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli Author: Granek, Elise F. Year: 2000 Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, as part of a project to assess areas for nature reserves which will be able to protect and conserve forest resources in the islands; the bat is postulated to be a useful indicator of undisturbed forest. Known roost sites (n=9) before the survey were between 500 and 1100 m altitude, on steeply sloping land, with some indigenous forest cover present. Thirteen new potential roost sites were identified, of which at least six were confirmed as roost sites for P. livingstonii. Bats showed positive associations with two tree species: Gambeya sp. and Nuxia pseudodentata. The study also investigated the participation by local village communities in monitoring bat populations, and the protection of roost sites. Close

• 3. [Article] Conservation des habitats de Roussettes de Livingstone – Les Massifs Forestiers d’Anjouan et Moheli, Comores: Utilisation d’Indicateurs sociaux et ecologiques

  Le déboisement sur les lles d'Anjouan et Moheli a augmenté a un taux alarmant au cours de ce siecle (PNUD 1998). Ce changement de la couverture des sols et des forets naturelles a des consequences nefastes ...

  Citation × Citation Citation Abstract Copy Title: Conservation des habitats de Roussettes de Livingstone – Les Massifs Forestiers d’Anjouan et Moheli, Comores: Utilisation d’Indicateurs sociaux et ecologiques Author: Granek, Elise F. Year: 2000 Le déboisement sur les lles d'Anjouan et Moheli a augmenté a un taux alarmant au cours de ce siecle (PNUD 1998). Ce changement de la couverture des sols et des forets naturelles a des consequences nefastes pour toutes les especes vivant sur les iles, en particulier pour les especes vegetales et animales endemiques, et les communautes humaines locales. Pour diminuer la pression anthropique sur Ie milieu naturel, le Fonds pour l'Environnement Mondial et Ie PNUD ont mis en place un projet de cinq ans qui travaille avec Ie Ministere comorien de l'Environnement pour creer un reseau d'aires protegees dans les trois iles qui forment la Republique Federale Islamique des Comores (PNUD rapport non pub lie). Deux de ces aires protegees integreront le milieu forestier. II s'agit de l'aire protegee de Moheli et de celle de la foret de Lingoni it Anjouan. La creation d'une aire protegee capable d'assurer une protection durable de Ia faune endemique des milieux forestiers ne peut se faire qu'avec la participation des communautes locales. II est donc important de mettre en place une approche qui permette de considerer les dimensions sociales et ecologiques de la conservation. Title: Conservation des habitats de Roussettes de Livingstone – Les Massifs Forestiers d’Anjouan et Moheli, Comores: Utilisation d’Indicateurs sociaux et ecologiques Author: Granek, Elise F. Year: 2000 Le déboisement sur les lles d'Anjouan et Moheli a augmenté a un taux alarmant au cours de ce siecle (PNUD 1998). Ce changement de la couverture des sols et des forets naturelles a des consequences nefastes pour toutes les especes vivant sur les iles, en particulier pour les especes vegetales et animales endemiques, et les communautes humaines locales. Pour diminuer la pression anthropique sur Ie milieu naturel, le Fonds pour l'Environnement Mondial et Ie PNUD ont mis en place un projet de cinq ans qui travaille avec Ie Ministere comorien de l'Environnement pour creer un reseau d'aires protegees dans les trois iles qui forment la Republique Federale Islamique des Comores (PNUD rapport non pub lie). Deux de ces aires protegees integreront le milieu forestier. II s'agit de l'aire protegee de Moheli et de celle de la foret de Lingoni it Anjouan. La creation d'une aire protegee capable d'assurer une protection durable de Ia faune endemique des milieux forestiers ne peut se faire qu'avec la participation des communautes locales. II est donc important de mettre en place une approche qui permette de considerer les dimensions sociales et ecologiques de la conservation. Close

• 4. [Article] Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing

  Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” ...

  Citation × Citation Citation Abstract Copy Title: Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing Author: Hayden, Heather Lyn, Granek, Elise F. Year: 2015 Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five study sites, each containing paired intact (+mangrove) and cleared (-mangrove) plots. Five sediment elevation pins were deployed in each plot: behind areas cleared of mangroves (-mangrove) and behind adjacent intact mangroves (+mangrove). Sediment elevation increased at intact mangrove sites (M= +3.83 mm, SE=0.95) whereas cleared mangrove areas suffered elevation loss (M= -7.30 mm, SE=3.38). Mangroves inshore of partial or continuous gaps in the adjacent fringing reefs had higher rates of elevation loss (M=-15.05mm) than mangroves inshore of continuous fringing reefs (M=-1.90mm). Our findings provide information on potential effects of mangrove clearing and the role of offshore habitat characteristics on coastal sediment trapping and maintenance of sediment elevation by mangroves. With implications for coastline capacity to adjust to sea level rise, these findings are relevant to management of coastal fringing mangrove forests across the Caribbean. Title: Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing Author: Hayden, Heather Lyn, Granek, Elise F. Year: 2015 Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five study sites, each containing paired intact (+mangrove) and cleared (-mangrove) plots. Five sediment elevation pins were deployed in each plot: behind areas cleared of mangroves (-mangrove) and behind adjacent intact mangroves (+mangrove). Sediment elevation increased at intact mangrove sites (M= +3.83 mm, SE=0.95) whereas cleared mangrove areas suffered elevation loss (M= -7.30 mm, SE=3.38). Mangroves inshore of partial or continuous gaps in the adjacent fringing reefs had higher rates of elevation loss (M=-15.05mm) than mangroves inshore of continuous fringing reefs (M=-1.90mm). Our findings provide information on potential effects of mangrove clearing and the role of offshore habitat characteristics on coastal sediment trapping and maintenance of sediment elevation by mangroves. With implications for coastline capacity to adjust to sea level rise, these findings are relevant to management of coastal fringing mangrove forests across the Caribbean. Close

• 5. [Article] Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach

  Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of ...

  Citation × Citation Citation Abstract Copy Title: Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach Author: Prichard, Emma C, Granek, Elise F. Year: 2016 Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change. Title: Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach Author: Prichard, Emma C, Granek, Elise F. Year: 2016 Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change. Close