At least half of the world's population resides in the coastal zone and the livelihoods of billio... more At least half of the world's population resides in the coastal zone and the livelihoods of billions of people are affected either directly or indirectly by the production and sustainability of nearshore fisheries. Landscape change, specifically development of tree plantations, is accelerating worldwide as developing countries integrate into global markets to sell goods, offer climate-mitigation services (carbon), and/or provide renewable energy. These changes can release excess nutrients into adjacent coastal waters causing eutrophication that alters the structure and function of coastal ecosystems. This study examined the relationship between coastal drainage basin land use/land cover change (LCLUC), specifically development of tree plantations, patterns of chlorophyll-a in nearshore coastal waters, and the biological condition of commercially important shellfish, Concholepas concholepas (loco) in southern Chile. Locos (N = 1374) were sampled across 13 watersheds (35 853 km 2 ) and 42 fisheries management areas (spanning 250 km of coastline). Locos harvested from management areas influenced by tree plantations had approximately 30% more endobiont (shell-boring) phoronids, almost twice as many endobiont polychaetes and twice as many epibiont (shell-attaching) barnacles than locos from areas in close proximity to watersheds dominated by native forests (15-20% of the watershed). Phoronid infested locos from coastal waters adjacent to watersheds with tree plantations were of relatively poor biological condition (smaller and narrower in width) and of reduced market value. Our study suggests that tree plantations result in indirect ecological impacts to coastal fisheries (more nutrients and higher phytoplankton biomass, resulting in smaller, low quality locos), and costs are born by coastal fishers (lower prices for locos). Increases in tree plantations could thus potentially significantly impact coastal fisheries worldwide and such problems should be managed as an interconnected network of land use change, oceanic ecosystems, and economic systems that are considered an integrated socio-ecological system.
We used cultural consensus models to test whether hunters shared perceptions of wildlife abundanc... more We used cultural consensus models to test whether hunters shared perceptions of wildlife abundance and the relative importance of hunting and fishing in a Guarayo indigenous community in the Bolivian Amazon. Results show that highly prized animals that were considered rare are either those with lower reproductive rates and more sensitivity to land use changes and harvest (white-lipped peccary and spider monkey) or those with marked seasonal distribution patterns (barred sorubim and tiger-fish). Rapidly reproducing and resilient species (agouti and armored catfish) were perceived as abundant. More tapirs and red brocket deer were present than predicted by scientific models possibly because hunters were harvesting these species in new forest management areas. Residents identified hunting and fishing among their most important livelihood activities, recognized bush meat and fish as basic food resources, and expected wildlife harvests to be part of their future livelihoods, although market-based livelihoods and domestic replacements for bush meat were reported.
Today researchers need an efficient and valid approach to mine and analyze the large amount of te... more Today researchers need an efficient and valid approach to mine and analyze the large amount of textual information that is available. Automated coding approaches offer promise but a major concern is the accuracy of such codes in capturing the meaning and intent of the original texts. We compare the recall (number of codes identified) and precision (accuracy of the codes) that included bodies of texts coded (1) manually by humans based on the Outline of Cultural Materials (OCM) code book, (2) semi-automatically by computers that used a human-generated content dictionary containing Rapid Ethnographic Retrieval (RER) codes, and (3) automatically by computers that used an automated version of the OCM content dictionary (AOCM). We applied network visualization and statistics to quantify the relative importance of codes. The semi-automatic coding approach had the highest balance of recall and precision. Network visualization and metrics identified relationships among concepts and frame codes within a context. Semiautomated approaches can code much more data in a shorter period of time than humans and researchers can more easily refine content dictionaries and analyses to address errors, which makes semi-automated coding a promising method to analyze the ever-expanding amount of textual information that is available today. #
We used local and landscape models to predict fish assemblages in the Great Swamp, NY, a region u... more We used local and landscape models to predict fish assemblages in the Great Swamp, NY, a region undergoing rapid development. Fish were surveyed across 17 sites. Fish-species richness, diversity, percent intolerant species, and IBI metrics for fish species richness, benthic insectivores, terete minnows, and dominant species were calculated. Local stream features were characterized and surrounding land cover/use was quantified at four different scales (reach, segment, network, and watershed). Regression analysis and multinomial cumulative logit models were used to predict how fish assemblages varied according to habitat characteristics. Within the local variables, pool variability predicted diversity and epifaunal substrate/available cover predicted percent intolerant species and IBI metrics for fsh species richness, benthic insectivores, and terete minnows. The scale of analysis influenced which landscape-level predictors measuring percent wetland, forest cover, or residential land use best explained diversity, percent intolerant species, and IBI metrics for benthic insectivores, terete minnows, and dominant species. Although no single model (local or landscape) best predicted assemblages, the land cover/use at the segment (100-m buffer for 1 km upstream) scale provides sufficient information about fish assemblages to support this scale as optimal for regional land-use planners. Our findings show that forest cover should be maintained to protect fish assemblages in the Great Swamp and development that alters stream-habitat heterogeneity should be curtailed.
Determinants of fisher success in southern Chile's loco (Concholepas concholepas) fishery are exa... more Determinants of fisher success in southern Chile's loco (Concholepas concholepas) fishery are examined by comparing fisher success in exclusive access territories that vary in relationship to tree-plantation development, which can affect shellfish quality. The relative importance of fishers' experience and capture technology (traditional measures of fisher success) are evaluated against environmental and geospatial characteristics. While knowledge and technology explained variation in catches, this did not translate into higher prices or profit. Fishers succeeded (gained higher prices for locos and had higher monthly incomes from their management areas) when they harvested shellfish from closed (exclusive) nearshore management areas where the environmental condition produced high quality locos regardless of their fishing experience, technology, and the geospatial features of management areas. Experienced fishers who worked in management areas near tree plantations that fail to produce resources of sufficient quality shifted to offshore fisheries where their experience counted. Offshore fishers working in the congrio (Genypterus chilensis) fishery likely exposed themselves to more risk and benefited from their experience and available technology; environmental condition and geospatial factors played little role in their success (price). Closed management areas provided resources to harvest, but may reduce a fisher's ability to adapt to environmental change because success depends on environmental factors outside of a fisher's control. Fishers were not financially rewarded for their experience or their technology in the loco fishery.
At least half of the world's population resides in the coastal zone and the livelihoods of billio... more At least half of the world's population resides in the coastal zone and the livelihoods of billions of people are affected either directly or indirectly by the production and sustainability of nearshore fisheries. Landscape change, specifically development of tree plantations, is accelerating worldwide as developing countries integrate into global markets to sell goods, offer climate-mitigation services (carbon), and/or provide renewable energy. These changes can release excess nutrients into adjacent coastal waters causing eutrophication that alters the structure and function of coastal ecosystems. This study examined the relationship between coastal drainage basin land use/land cover change (LCLUC), specifically development of tree plantations, patterns of chlorophyll-a in nearshore coastal waters, and the biological condition of commercially important shellfish, Concholepas concholepas (loco) in southern Chile. Locos (N = 1374) were sampled across 13 watersheds (35 853 km 2 ) and 42 fisheries management areas (spanning 250 km of coastline). Locos harvested from management areas influenced by tree plantations had approximately 30% more endobiont (shell-boring) phoronids, almost twice as many endobiont polychaetes and twice as many epibiont (shell-attaching) barnacles than locos from areas in close proximity to watersheds dominated by native forests (15-20% of the watershed). Phoronid infested locos from coastal waters adjacent to watersheds with tree plantations were of relatively poor biological condition (smaller and narrower in width) and of reduced market value. Our study suggests that tree plantations result in indirect ecological impacts to coastal fisheries (more nutrients and higher phytoplankton biomass, resulting in smaller, low quality locos), and costs are born by coastal fishers (lower prices for locos). Increases in tree plantations could thus potentially significantly impact coastal fisheries worldwide and such problems should be managed as an interconnected network of land use change, oceanic ecosystems, and economic systems that are considered an integrated socio-ecological system.
We used cultural consensus models to test whether hunters shared perceptions of wildlife abundanc... more We used cultural consensus models to test whether hunters shared perceptions of wildlife abundance and the relative importance of hunting and fishing in a Guarayo indigenous community in the Bolivian Amazon. Results show that highly prized animals that were considered rare are either those with lower reproductive rates and more sensitivity to land use changes and harvest (white-lipped peccary and spider monkey) or those with marked seasonal distribution patterns (barred sorubim and tiger-fish). Rapidly reproducing and resilient species (agouti and armored catfish) were perceived as abundant. More tapirs and red brocket deer were present than predicted by scientific models possibly because hunters were harvesting these species in new forest management areas. Residents identified hunting and fishing among their most important livelihood activities, recognized bush meat and fish as basic food resources, and expected wildlife harvests to be part of their future livelihoods, although market-based livelihoods and domestic replacements for bush meat were reported.
Today researchers need an efficient and valid approach to mine and analyze the large amount of te... more Today researchers need an efficient and valid approach to mine and analyze the large amount of textual information that is available. Automated coding approaches offer promise but a major concern is the accuracy of such codes in capturing the meaning and intent of the original texts. We compare the recall (number of codes identified) and precision (accuracy of the codes) that included bodies of texts coded (1) manually by humans based on the Outline of Cultural Materials (OCM) code book, (2) semi-automatically by computers that used a human-generated content dictionary containing Rapid Ethnographic Retrieval (RER) codes, and (3) automatically by computers that used an automated version of the OCM content dictionary (AOCM). We applied network visualization and statistics to quantify the relative importance of codes. The semi-automatic coding approach had the highest balance of recall and precision. Network visualization and metrics identified relationships among concepts and frame codes within a context. Semiautomated approaches can code much more data in a shorter period of time than humans and researchers can more easily refine content dictionaries and analyses to address errors, which makes semi-automated coding a promising method to analyze the ever-expanding amount of textual information that is available today. #
We used local and landscape models to predict fish assemblages in the Great Swamp, NY, a region u... more We used local and landscape models to predict fish assemblages in the Great Swamp, NY, a region undergoing rapid development. Fish were surveyed across 17 sites. Fish-species richness, diversity, percent intolerant species, and IBI metrics for fish species richness, benthic insectivores, terete minnows, and dominant species were calculated. Local stream features were characterized and surrounding land cover/use was quantified at four different scales (reach, segment, network, and watershed). Regression analysis and multinomial cumulative logit models were used to predict how fish assemblages varied according to habitat characteristics. Within the local variables, pool variability predicted diversity and epifaunal substrate/available cover predicted percent intolerant species and IBI metrics for fsh species richness, benthic insectivores, and terete minnows. The scale of analysis influenced which landscape-level predictors measuring percent wetland, forest cover, or residential land use best explained diversity, percent intolerant species, and IBI metrics for benthic insectivores, terete minnows, and dominant species. Although no single model (local or landscape) best predicted assemblages, the land cover/use at the segment (100-m buffer for 1 km upstream) scale provides sufficient information about fish assemblages to support this scale as optimal for regional land-use planners. Our findings show that forest cover should be maintained to protect fish assemblages in the Great Swamp and development that alters stream-habitat heterogeneity should be curtailed.
Determinants of fisher success in southern Chile's loco (Concholepas concholepas) fishery are exa... more Determinants of fisher success in southern Chile's loco (Concholepas concholepas) fishery are examined by comparing fisher success in exclusive access territories that vary in relationship to tree-plantation development, which can affect shellfish quality. The relative importance of fishers' experience and capture technology (traditional measures of fisher success) are evaluated against environmental and geospatial characteristics. While knowledge and technology explained variation in catches, this did not translate into higher prices or profit. Fishers succeeded (gained higher prices for locos and had higher monthly incomes from their management areas) when they harvested shellfish from closed (exclusive) nearshore management areas where the environmental condition produced high quality locos regardless of their fishing experience, technology, and the geospatial features of management areas. Experienced fishers who worked in management areas near tree plantations that fail to produce resources of sufficient quality shifted to offshore fisheries where their experience counted. Offshore fishers working in the congrio (Genypterus chilensis) fishery likely exposed themselves to more risk and benefited from their experience and available technology; environmental condition and geospatial factors played little role in their success (price). Closed management areas provided resources to harvest, but may reduce a fisher's ability to adapt to environmental change because success depends on environmental factors outside of a fisher's control. Fishers were not financially rewarded for their experience or their technology in the loco fishery.
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