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Iain M Suthers - One of the best experts on this subject based on the ideXlab platform.
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Modelling the distribution of fish around an Artificial Reef
Marine and Freshwater Research, 2017Co-Authors: James A Smith, Michael B. Lowry, William K. Cornwell, Iain M SuthersAbstract:Artificial Reefs are a widely used tool aimed at fishery enhancement, and measuring the scale at which fish assemblages associate with these Artificial habitat patches can aid Reef design and spatial arrangement. The present study used rapidly deployed underwater video (drop cameras) to determine the magnitude and spatial scale of associations between a fish assemblage and a coastal Artificial Reef. Count data from drop cameras were combined with distance and bathymetry information to create a suite of explanatory generalised linear mixed models (GLMMs). The GLMMs showed that Artificial Reefs can influence surrounding fish abundance, but that the magnitude and scale is species specific. Three of the eight taxonomic groups examined showed a positive association with the Artificial Reef (with model fit poor for the remaining groups); and depth and bottom cover were also influential variables. The spatial scales of these associations with the Artificial Reef were small, and it was generally the presence of Reef (i.e. a Reef bottom type) that explained more variation in fish abundance than did distance to Reef. The schooling baitfish yellowtail scad was an exception, and had elevated abundance >50m from the Artificial Reef. Further distribution modelling of Artificial Reefs will benefit species-specific design and management of Artificial Reefs.
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The effects of substratum material and surface orientation on the developing epibenthic community on a designed Artificial Reef
Biofouling, 2016Co-Authors: Shinjiro Ushiama, Michael B. Lowry, James A Smith, Iain M Suthers, Emma L. JohnstonAbstract:AbstractArtificial Reefs provide shelter and can be an important source of food for fish depending on the epibenthic community on the structure. The growth and diversity of this community is influenced by the substratum material and the surface orientation of the Reef. Settlement plates of four materials (Perspex, sandstone, wood and steel) were deployed in three orientations (upwards, downwards and vertical) at a depth of 33 m on a designed Artificial Reef (DAR) off the coast of Sydney, Australia. After three months, the steel surfaces had lower invertebrate species richness, total abundance and diversity compared to other surfaces. Steel was not an ideal material for the initial recruitment and growth of epibenthic invertebrates. A longer duration would be required to develop a mature epibenthic community. Surface orientation had species-specific impacts. Surface material and orientation are important factors for developing epibenthic assemblages, and are thus likely to affect the broader Artificial ree...
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monitoring boat based recreational fishing effort at a nearshore Artificial Reef with a shore based camera
Fisheries Research, 2016Co-Authors: Krystle Keller, Michael B. Lowry, Aldo S Steffe, Jeffrey J Murphy, Iain M SuthersAbstract:Abstract Recreational fishing effort was quantified at a 700 m3 steel Artificial Reef (AR) off coastal Sydney with a shore-based camera (06:00–18:00) over a two-year period. Stratified random sampling was used to select days for analysis of fishing effort from digital images. Fishing effort estimates derived from the digital images were adjusted to account for visibility bias using information from a validation study. The levels of effort recorded in the first two seasons were low as the AR had been recently deployed and colonization of the AR by sessile organisms and fishes was still occurring. The effort intensity (fisher hours per square kilometer) at the Sydney AR was compared with three South Australian ARs and 14 estuarine fisheries in New South Wales (NSW) to provide context for the study. Effort intensity at the AR was found to be up to 12 times higher than that recorded from some estuarine fisheries in NSW. Conversely, the levels of effort intensity at two South Australian ARs were much higher compared to those at the Sydney AR site in both survey years. Effort intensity comparisons showed that the relative levels of usage at Australian ARs were higher than those recorded from estuarine fisheries. The Sydney AR provides diverse fishing opportunities that may be concentrated in a small area. Camera-based technologies can provide a solution for cost effective monitoring of AR sites, providing the accuracy of fishing effort information derived from camera images is validated. Our study has broad implications for other recreational ARs, including many future deployments planned for eastern Australia.
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Zooplanktivory is a key process for fish production on a coastal Artificial Reef
Marine Ecology Progress Series, 2015Co-Authors: Curtis Champion, Iain M Suthers, James A SmithAbstract:Artificial Reefs continue to be deployed in coastal areas to enhance local fisheries. An important factor influencing the success of Artificial Reefs may be the provision of refuge for zooplank- tivorous fishes, which use Artificial Reefs as a base to forage the surrounding zooplankton. A numerical model was developed to quantify this trophic pathway on a designed coastal Artificial Reef, using field-parameterised data for zooplankton biomass, current velocity, and the consumption rate and abundance of a Reef-resident zooplanktivorous fish (Atypichthys strigatus). The model estimated that this species consumed ~2.9 kg (1.0 g m −3 ) of zoo- plankton per day on this Artificial Reef, which repre- sents only 0.35% of the total zooplankton biomass. The ability of this Artificial Reef to support ~130 kg standing stock of this species suggests that the zoo- plankton pathway is a reliable mechanism for fish production. A second model explored the influence of Reef size on zooplanktivorous fish densities and the supply of zooplankton required to sustain their consumption rate. As Reef size increased, the ratio between the foraging volume and refuge volume declined, meaning that small Reefs have lots of food and not much refuge, and large Reefs can have lots of refuge but not enough food. This indicates that Reef size can be manipulated to maximise fish abun- dance while avoiding food limitation. Reef size, shape, and orientation should be considered care- fully during the planning of Artificial Reefs, as it can greatly influence the foraging of Reef-resident zoo- planktivorous fishes and thus influence the entire Reef assemblage.
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The influence of an offshore Artificial Reef on the abundance of fish in the surrounding pelagic environment
Marine and Freshwater Research, 2015Co-Authors: Molly E. Scott, Michael B. Lowry, James A Smith, Matthew D Taylor, Iain M SuthersAbstract:Artificial Reefs are a popular fisheries management tool, but the effect of these Reefs on the abundance of fish in the surrounding pelagic environment is uncertain. Pelagic baited remote underwater video (PBRUV) was used to observe the fish assemblage surrounding an offshore Artificial Reef (OAR), near Sydney, Australia. PBRUVs were deployed at three distances (30, 100, 500m) from the OAR, and compared with a drop camera deployed directly over the OAR. There was a significantly greater abundance of fish on the OAR, but no significant difference in abundance at the 30-, 100- or 500-m distances. Two highly mobile non-resident species (Seriola lalandi, Pseudocaranx dentex) were significantly more abundant on the OAR, but this association was not detected 30m away. The lack of a significant difference in total fish abundance, or in assemblage composition, between the 30-, 100- and 500-m distances suggests that any association with the OAR is on a localised scale (
Miguel N. Santos - One of the best experts on this subject based on the ideXlab platform.
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Local fishermen's perceptions of the usefulness of Artificial Reef ecosystem services in Portugal
PeerJ, 2019Co-Authors: Jorge Ramos, Pedro G. Lino, Amber Himes-cornell, Miguel N. SantosAbstract:Proponents of Artificial Reef (AR) deployment are often motivated by the usefulness of such structures. The usefulness of ARs is related to their capability of providing ecosystem services/additional functions. We present two distinct Portuguese AR case studies: (1) The Nazare Reef off the central coast of Portugal and (2) the Oura Reef off the Algarve coast. Semi-structured interviews were conducted with local fishermen in the fishing towns of Nazare and Quarteira pre-and post-AR deployment. The main focus of the interviews was to understand fishermen's perception of AR usefulness (or lack thereof) in terms of nine ecosystem services/additional functions potentially provided by the ARs. We tested the null hypothesis that ARs do not provide additional ecosystem services/additional functions. When queried pre-AR deployment, fishermen indicated that ARs are most likely to provide three ecosystem services: "habitat and refuge," "biodiversity preservation" and "food production." Fishermen had similar perceptions post-deployment. For the Nazare Reef, fishermen tended to have a positive or neutral perception of ecosystem services/additional functions being provided by ARs. For the Oura Reef, fishermen tended to have a mostly neutral perception of AR ecosystem services; however, there were also some positive and other negative perceptions. It was difficult for stakeholders to conceptualize some of the ecosystem services/additional functions provided by ARs prior to actively using them. As a result, some stakeholders changed their perception of the ecosystem services/additional functions after using the structures. These results indicate that stakeholders likely need to perceive ARs as useful in order for them to provide their support for AR installation. Likewise, their support is often needed to justify the use of public funds to install ARs, therefore making it imperative for resource managers to undertake similar interviews with fishermen when considering the use of ARs in other areas.
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Local fishermen’s perceptions of the usefulness of Artificial Reef ecosystem services in Portugal
PeerJ Inc., 2019Co-Authors: Jorge Ramos, Pedro G. Lino, Amber Himes-cornell, Miguel N. SantosAbstract:Proponents of Artificial Reef (AR) deployment are often motivated by the usefulness of such structures. The usefulness of ARs is related to their capability of providing ecosystem services/additional functions. We present two distinct Portuguese AR case studies: (1) The Nazaré Reef off the central coast of Portugal and (2) the Oura Reef off the Algarve coast. Semi-structured interviews were conducted with local fishermen in the fishing towns of Nazaré and Quarteira pre-and post-AR deployment. The main focus of the interviews was to understand fishermen’s perception of AR usefulness (or lack thereof) in terms of nine ecosystem services/additional functions potentially provided by the ARs. We tested the null hypothesis that ARs do not provide additional ecosystem services/additional functions. When queried pre-AR deployment, fishermen indicated that ARs are most likely to provide three ecosystem services: “habitat and refuge,” “biodiversity preservation” and “food production.” Fishermen had similar perceptions post-deployment. For the Nazaré Reef, fishermen tended to have a positive or neutral perception of ecosystem services/additional functions being provided by ARs. For the Oura Reef, fishermen tended to have a mostly neutral perception of AR ecosystem services; however, there were also some positive and other negative perceptions. It was difficult for stakeholders to conceptualize some of the ecosystem services/additional functions provided by ARs prior to actively using them. As a result, some stakeholders changed their perception of the ecosystem services/additional functions after using the structures. These results indicate that stakeholders likely need to perceive ARs as useful in order for them to provide their support for AR installation. Likewise, their support is often needed to justify the use of public funds to install ARs, therefore making it imperative for resource managers to undertake similar interviews with fishermen when considering the use of ARs in other areas
Jorge Ramos - One of the best experts on this subject based on the ideXlab platform.
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Local fishermen's perceptions of the usefulness of Artificial Reef ecosystem services in Portugal
PeerJ, 2019Co-Authors: Jorge Ramos, Pedro G. Lino, Amber Himes-cornell, Miguel N. SantosAbstract:Proponents of Artificial Reef (AR) deployment are often motivated by the usefulness of such structures. The usefulness of ARs is related to their capability of providing ecosystem services/additional functions. We present two distinct Portuguese AR case studies: (1) The Nazare Reef off the central coast of Portugal and (2) the Oura Reef off the Algarve coast. Semi-structured interviews were conducted with local fishermen in the fishing towns of Nazare and Quarteira pre-and post-AR deployment. The main focus of the interviews was to understand fishermen's perception of AR usefulness (or lack thereof) in terms of nine ecosystem services/additional functions potentially provided by the ARs. We tested the null hypothesis that ARs do not provide additional ecosystem services/additional functions. When queried pre-AR deployment, fishermen indicated that ARs are most likely to provide three ecosystem services: "habitat and refuge," "biodiversity preservation" and "food production." Fishermen had similar perceptions post-deployment. For the Nazare Reef, fishermen tended to have a positive or neutral perception of ecosystem services/additional functions being provided by ARs. For the Oura Reef, fishermen tended to have a mostly neutral perception of AR ecosystem services; however, there were also some positive and other negative perceptions. It was difficult for stakeholders to conceptualize some of the ecosystem services/additional functions provided by ARs prior to actively using them. As a result, some stakeholders changed their perception of the ecosystem services/additional functions after using the structures. These results indicate that stakeholders likely need to perceive ARs as useful in order for them to provide their support for AR installation. Likewise, their support is often needed to justify the use of public funds to install ARs, therefore making it imperative for resource managers to undertake similar interviews with fishermen when considering the use of ARs in other areas.
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Local fishermen’s perceptions of the usefulness of Artificial Reef ecosystem services in Portugal
PeerJ Inc., 2019Co-Authors: Jorge Ramos, Pedro G. Lino, Amber Himes-cornell, Miguel N. SantosAbstract:Proponents of Artificial Reef (AR) deployment are often motivated by the usefulness of such structures. The usefulness of ARs is related to their capability of providing ecosystem services/additional functions. We present two distinct Portuguese AR case studies: (1) The Nazaré Reef off the central coast of Portugal and (2) the Oura Reef off the Algarve coast. Semi-structured interviews were conducted with local fishermen in the fishing towns of Nazaré and Quarteira pre-and post-AR deployment. The main focus of the interviews was to understand fishermen’s perception of AR usefulness (or lack thereof) in terms of nine ecosystem services/additional functions potentially provided by the ARs. We tested the null hypothesis that ARs do not provide additional ecosystem services/additional functions. When queried pre-AR deployment, fishermen indicated that ARs are most likely to provide three ecosystem services: “habitat and refuge,” “biodiversity preservation” and “food production.” Fishermen had similar perceptions post-deployment. For the Nazaré Reef, fishermen tended to have a positive or neutral perception of ecosystem services/additional functions being provided by ARs. For the Oura Reef, fishermen tended to have a mostly neutral perception of AR ecosystem services; however, there were also some positive and other negative perceptions. It was difficult for stakeholders to conceptualize some of the ecosystem services/additional functions provided by ARs prior to actively using them. As a result, some stakeholders changed their perception of the ecosystem services/additional functions after using the structures. These results indicate that stakeholders likely need to perceive ARs as useful in order for them to provide their support for AR installation. Likewise, their support is often needed to justify the use of public funds to install ARs, therefore making it imperative for resource managers to undertake similar interviews with fishermen when considering the use of ARs in other areas
Xujian Lin - One of the best experts on this subject based on the ideXlab platform.
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biogenic sulfuric acid corrosion resistance of new Artificial Reef concrete
Construction and Building Materials, 2018Co-Authors: Yu Yang, Caiyi Chen, Xujian Lin, Zhengxian YangAbstract:Abstract Through biogenic sulfuric acid attack on concrete, comparisons between ordinary Portland cement concrete (OPCC) and new Artificial Reef concrete (NARC) prepared with sulphoaluminate cement, marine sand and sea water were made. Biogenic sulfuric acid corrosion resistance was studied by analyzing the surface and localized morphology, mass loss and compressive strength of both concrete specimens. The corrosion products were investigated by environmental scanning electron microscope (ESEM), X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR). Results showed that the visually apparent corrosion degree and loss rates of mass and compressive strength are higher for OPCC than for NARC following exposure to biogenic sulfuric acid.
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workability mechanical properties and affinity of Artificial Reef concrete
Construction and Building Materials, 2015Co-Authors: Caiyi Chen, Yizhou Zhuang, Xujian LinAbstract:Abstract A new Artificial Reef concrete (NARC) with sulphoaluminate cement, marine sand and sea water et al. was proposed. The effect of cement type, sand type and water type on the workability (namely slump, slump loss cohesiveness, water retention), mechanical properties namely compressive strength, splitting tensile strength and dynamic elastic modulus) and affinity (namely surface initial pH value and the leaching rate of alkaline material in concrete) of concrete was studied. The microstructure of concrete was detected by X-ray diffraction, scanning electron microscope and pore structure analyzer, respectively. The studies show that NARC has superior workability, mechanical properties and affinity compared to ordinary Portland cement concrete with river sand and fresh water. Therefore, the feasibility of NARC in Artificial Reef is verified.
Michael B. Lowry - One of the best experts on this subject based on the ideXlab platform.
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Modelling the distribution of fish around an Artificial Reef
Marine and Freshwater Research, 2017Co-Authors: James A Smith, Michael B. Lowry, William K. Cornwell, Iain M SuthersAbstract:Artificial Reefs are a widely used tool aimed at fishery enhancement, and measuring the scale at which fish assemblages associate with these Artificial habitat patches can aid Reef design and spatial arrangement. The present study used rapidly deployed underwater video (drop cameras) to determine the magnitude and spatial scale of associations between a fish assemblage and a coastal Artificial Reef. Count data from drop cameras were combined with distance and bathymetry information to create a suite of explanatory generalised linear mixed models (GLMMs). The GLMMs showed that Artificial Reefs can influence surrounding fish abundance, but that the magnitude and scale is species specific. Three of the eight taxonomic groups examined showed a positive association with the Artificial Reef (with model fit poor for the remaining groups); and depth and bottom cover were also influential variables. The spatial scales of these associations with the Artificial Reef were small, and it was generally the presence of Reef (i.e. a Reef bottom type) that explained more variation in fish abundance than did distance to Reef. The schooling baitfish yellowtail scad was an exception, and had elevated abundance >50m from the Artificial Reef. Further distribution modelling of Artificial Reefs will benefit species-specific design and management of Artificial Reefs.
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The effects of substratum material and surface orientation on the developing epibenthic community on a designed Artificial Reef
Biofouling, 2016Co-Authors: Shinjiro Ushiama, Michael B. Lowry, James A Smith, Iain M Suthers, Emma L. JohnstonAbstract:AbstractArtificial Reefs provide shelter and can be an important source of food for fish depending on the epibenthic community on the structure. The growth and diversity of this community is influenced by the substratum material and the surface orientation of the Reef. Settlement plates of four materials (Perspex, sandstone, wood and steel) were deployed in three orientations (upwards, downwards and vertical) at a depth of 33 m on a designed Artificial Reef (DAR) off the coast of Sydney, Australia. After three months, the steel surfaces had lower invertebrate species richness, total abundance and diversity compared to other surfaces. Steel was not an ideal material for the initial recruitment and growth of epibenthic invertebrates. A longer duration would be required to develop a mature epibenthic community. Surface orientation had species-specific impacts. Surface material and orientation are important factors for developing epibenthic assemblages, and are thus likely to affect the broader Artificial ree...
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monitoring boat based recreational fishing effort at a nearshore Artificial Reef with a shore based camera
Fisheries Research, 2016Co-Authors: Krystle Keller, Michael B. Lowry, Aldo S Steffe, Jeffrey J Murphy, Iain M SuthersAbstract:Abstract Recreational fishing effort was quantified at a 700 m3 steel Artificial Reef (AR) off coastal Sydney with a shore-based camera (06:00–18:00) over a two-year period. Stratified random sampling was used to select days for analysis of fishing effort from digital images. Fishing effort estimates derived from the digital images were adjusted to account for visibility bias using information from a validation study. The levels of effort recorded in the first two seasons were low as the AR had been recently deployed and colonization of the AR by sessile organisms and fishes was still occurring. The effort intensity (fisher hours per square kilometer) at the Sydney AR was compared with three South Australian ARs and 14 estuarine fisheries in New South Wales (NSW) to provide context for the study. Effort intensity at the AR was found to be up to 12 times higher than that recorded from some estuarine fisheries in NSW. Conversely, the levels of effort intensity at two South Australian ARs were much higher compared to those at the Sydney AR site in both survey years. Effort intensity comparisons showed that the relative levels of usage at Australian ARs were higher than those recorded from estuarine fisheries. The Sydney AR provides diverse fishing opportunities that may be concentrated in a small area. Camera-based technologies can provide a solution for cost effective monitoring of AR sites, providing the accuracy of fishing effort information derived from camera images is validated. Our study has broad implications for other recreational ARs, including many future deployments planned for eastern Australia.
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The influence of an offshore Artificial Reef on the abundance of fish in the surrounding pelagic environment
Marine and Freshwater Research, 2015Co-Authors: Molly E. Scott, Michael B. Lowry, James A Smith, Matthew D Taylor, Iain M SuthersAbstract:Artificial Reefs are a popular fisheries management tool, but the effect of these Reefs on the abundance of fish in the surrounding pelagic environment is uncertain. Pelagic baited remote underwater video (PBRUV) was used to observe the fish assemblage surrounding an offshore Artificial Reef (OAR), near Sydney, Australia. PBRUVs were deployed at three distances (30, 100, 500m) from the OAR, and compared with a drop camera deployed directly over the OAR. There was a significantly greater abundance of fish on the OAR, but no significant difference in abundance at the 30-, 100- or 500-m distances. Two highly mobile non-resident species (Seriola lalandi, Pseudocaranx dentex) were significantly more abundant on the OAR, but this association was not detected 30m away. The lack of a significant difference in total fish abundance, or in assemblage composition, between the 30-, 100- and 500-m distances suggests that any association with the OAR is on a localised scale (
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the influence of an offshore Artificial Reef on the abundance of fish in the surrounding pelagic environment
Marine and Freshwater Research, 2015Co-Authors: Molly E. Scott, Michael B. Lowry, James A Smith, Matthew D Taylor, Iain M SuthersAbstract:Artificial Reefs are a popular fisheries management tool, but the effect of these Reefs on the abundance of fish in the surrounding pelagic environment is uncertain. Pelagic baited remote underwater video (PBRUV) was used to observe the fish assemblage surrounding an offshore Artificial Reef (OAR), near Sydney, Australia. PBRUVs were deployed at three distances (30, 100, 500m) from the OAR, and compared with a drop camera deployed directly over the OAR. There was a significantly greater abundance of fish on the OAR, but no significant difference in abundance at the 30-, 100- or 500-m distances. Two highly mobile non-resident species (Seriola lalandi, Pseudocaranx dentex) were significantly more abundant on the OAR, but this association was not detected 30m away. The lack of a significant difference in total fish abundance, or in assemblage composition, between the 30-, 100- and 500-m distances suggests that any association with the OAR is on a localised scale (<30m). One exception was the ocean leatherjacket (Nelusetta ayraudi), which had an association detected 100m from the OAR. This predominantly small-scale effect may be influenced by the proximity of this OAR to numerous natural Reefs.