Journal articles: 'Fish habitat assessment'

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Pratt, Thomas C., and Karen E. Smokorowski. "Fish habitat management implications of the summer habitat use by littoral fishes in a north temperate, mesotrophic lake." Canadian Journal of Fisheries and Aquatic Sciences 60, no. 3 (March 1, 2003): 286–300. http://dx.doi.org/10.1139/f03-022.

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Compensation measures in response to Fisheries and Oceans Canada (DFO) Policy for the Management of Fish Habitat includes provisions for habitat creation and enhancement. Thus, an assessment of nearshore habitat utilization patterns by fishes is needed to put DFO compensation measures in the context of the "no net loss of the productive capacity of fish habitat" directive. Measures of abundance, richness, and diversity of fishes were compared across nine habitat types in a lake using rapid visual underwater assessment. Multivariate analyses separated habitats into three groups and identified two distinct species assemblages. Most species were associated with macrophytes, but a few were primarily associated with rocky substrate. Shallow mud (open) habitats contained significantly fewer species and had lower mean scores and diversity than all other habitat types. Rocky habitats had lower mean scores and diversity than some vegetated habitat types containing similar fish assemblages. Surprisingly, within-site fish assemblage heterogeneity was similar to among-site heterogeneity, and among-habitat heterogeneity was lower than within-habitat heterogeneity, further supporting our inability to distinguish among vegetated habitat types. Our results suggest that habitat heterogeneity is critical in maintaining diverse communities and that compensation measures should account for differences in fishhabitat associations among varied habitats.

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Minns, Charles K., and James E. Moore. "Assessment of net change of productive capacity of fish habitats: the role of uncertainty and complexity in decision making." Canadian Journal of Fisheries and Aquatic Sciences 60, no. 1 (January 1, 2003): 100–116. http://dx.doi.org/10.1139/f02-168.

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Canada's fish habitat management is guided by the principle of "no net loss of the productive capacity of fish habitat" (NNL). Many development proposals are assessed using habitat information alone, rather than fish data. Because fishhabitat linkages are often obscured by uncertainty, uncertainty must be factored into NNL assessments. Using a quantitative framework for assessing NNL and lake habitats as a context, the implications of uncertainty for decision making are examined. The overall behaviour of a net change equation given uncertainty is explored using Monte Carlo simulation. Case studies from Great Lakes development projects are examined using interval analysis. The results indicate that uncertainty, even when large, can be incorporated into assessments. This has important implications for the habitat management based on NNL. First, schemas to specify relative levels of uncertainty using simple habitat classifications can support robust decision making. Second, attaining NNL requires greater emphasis on minimizing habitat loss and creating new areas to compensate for losses elsewhere and less on detailing small incremental changes in modified habitats where the fish response is difficult to demonstrate. Third, the moderate to high levels of uncertainty in fishhabitat linkages require that created compensation is at least twice the losses to reasonably ensure NNL.

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Rosenfeld, Jordan S., and Todd Hatfield. "Information needs for assessing critical habitat of freshwater fish." Canadian Journal of Fisheries and Aquatic Sciences 63, no. 3 (March 1, 2006): 683–98. http://dx.doi.org/10.1139/f05-242.

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The core assumptions of critical habitat designation are a positive relationship between habitat and population size and that a minimum habitat area is required to meet a recovery target. Effects of habitat on population limitation scale from (i) effects on performance of individuals (growth, survival, fecundity) within a life history stage, to (ii) limitation of populations by habitats associated with specific life history stages, and (iii) larger-scale habitat structure required for metapopulation persistence. The minimum subset of habitats required to achieve a recovery target will depend on the extent, quality, and spatial configuration of habitats available to sequential life history stages. Although populations may be limited by available habitat for a single life history stage, altering habitat quality for subsequent stages will also affect individual survival and population size, providing multiple leverage points within a life history for habitat management to achieve recovery targets. When habitat-explicit demographic data are lacking, consequences of uncertainty in critical habitat assessment need to be explicit, and research should focus on identifying habitats most likely to be limiting based on species biology.

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Minns, C. K. "Quantifying “no net loss” of productivity of fish habitats." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 10 (October 1, 1997): 2463–73. http://dx.doi.org/10.1139/f97-149.

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A net change equation is derived for assessing no net loss of productivity of fish habitat (NNL). NNL is the guiding principle of the Canadian policy for the management of fish habitat. The equation provides a middle ground between the extremes of no conservation and no development. Projects affecting fish habitat are accountable for the productive capacity in loss areas and the difference between current and future productivities in modified areas. The equation implies quantitative conservation targets overall and loss-offsetting equivalencies in modified habitat areas. Generalization of the net change equation to heterogeneous habitats is illustrated with a development in a coastal wetland on the Great Lakes. The net change framework has implications for linkages between suitable habitat supply and fish population dynamics. Area fish habitat management plans envisioned in the policy and site-level net change assessments are connected. Quantitative ways are proposed for simultaneous assessment of NNL and ``harmful alteration, disruption, or destruction'' of fish habitat, as required in the Canadian Fisheries Act. Defensible methods for applying the net change equation are superior to earlier nonquantitative approaches. If the available science is insufficient, the precautionary principle is recommended. Future development steps for the quantitative net change framework are suggested.

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Jenkins, Amy R., and Ernest R. Keeley. "Bioenergetic assessment of habitat quality for stream-dwelling cutthroat trout (Oncorhynchus clarkii bouvieri) with implications for climate change and nutrient supplementation." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 2 (February 2010): 371–85. http://dx.doi.org/10.1139/f09-193.

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We used a bioenergetic model to determine if cutthroat trout ( Oncorhynchus clarkii bouvieri ) abundance was related to net energy intake rates (NEI) and the proportion of suitable habitat and to evaluate potential changes in habitat quality due to climate change and stream fertilization efforts. We conducted monthly sampling of cutthroat trout, invertebrate drift, and physical habitat features in pool and riffle habitats. Fish in this study selected foraging positions that enabled them to maximize NEI, and most fish were capable of sustaining high growth rates from July to September. Mean NEI and the proportion of suitable habitat at sites were greater in pools relative to riffle habitats and declined from July to October, primarily due to a decline in temperature over the four months. Cutthroat trout biomass was significantly related to NEI and the proportion of suitable habitat at a site. Model simulations indicated that climate change might reduce habitat quality for small-bodied trout, while extending the growing season for larger fish. Increased food abundance provided only marginal changes to model outcomes, whereas reductions in food significantly reduced habitat quality.

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Searcy, Steven P., David B. Eggleston, and Jonathan A. Hare. "Is growth a reliable indicator of habitat quality and essential fish habitat for a juvenile estuarine fish?" Canadian Journal of Fisheries and Aquatic Sciences 64, no. 4 (April 1, 2007): 681–91. http://dx.doi.org/10.1139/f07-038.

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A common assumption throughout the marine ecological and fisheries literature is that growth is a valid indicator of habitat quality and can be used as a criterion for designation of essential fish habitat (EFH). In this study, the validity of growth as an index of habitat quality was tested by examining how variability in otolith growth was related to abiotic and biotic environmental conditions and could be biased by previous growth history, density dependence, and selective mortality. The study was conducted with juvenile Atlantic croaker (Micropogonias undulatus) collected in two North Carolina, USA, estuaries during two seasons of two recruitment years. Water temperature, a component of habitat quality, explained nearly 40% of the variability in juvenile otolith growth. There was also evidence that estimates of growth could be biased by density dependence (slower growth at higher conspecific abundance) and by selective mortality (higher mortality of individuals with relatively slower larval and juvenile otolith growth). Studies using growth-based assessment of habitat quality that fail to identify factors underlying growth rate differences among habitats may reach incorrect decisions regarding quality of different habitats and assignment of EFH.

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Stål, Johan, and Leif Pihl. "Quantitative assessment of the area of shallow habitat for fish on the Swedish west coast." ICES Journal of Marine Science 64, no. 3 (March 2, 2007): 446–52. http://dx.doi.org/10.1093/icesjms/fsm018.

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Abstract Stål, J., and Pihl, L. 2007. Quantitative assessment of the area of shallow habitat for fish on the Swedish west coast. – ICES Journal of Marine Science, 64: 446–452. Much effort has been focused recently on juvenile and adult fish habitat use in shallow coastal areas. However, to understand fully the importance of such habitats for fish production it is necessary also to quantify the area of existing habitat types. We inventory and quantify the area of major habitat types in a 1000 km2 area of the Swedish west coast, on a scale appropriate for coastal-zone management. An echosounder and GPS-transmitter mounted on a small boat were used to estimate the distribution of habitat along transects in seven regions of differing coastal morphology. The signal from the echosounder separated major habitat types, and recordings were verified by video documentation and visually. The information was used with GIS-software to estimate the quantitative extent of bottom habitats at depth ranges of 0–3, 3–6, and 6–10 m. Of the major habitat types, soft substrata dominated all except one region, and increased in size with depth in all regions. There were rocky substrata in all regions, but as steep rock walls in the north and more gently sloping substrata with pebbles and boulders in the south. Approximately half the rocky habitat was in the shallowest depth range. Seagrass meadows on soft substrata were mainly in the shallow protected archipelago of the central coast.

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Kovalenko, Katya E., Lucinda B. Johnson, Catherine M. Riseng, Matthew J. Cooper, Kristofer Johnson, Lacey A. Mason, James E. McKenna, Beth L. Sparks-Jackson, and Donald G. Uzarski. "Great Lakes coastal fish habitat classification and assessment." Journal of Great Lakes Research 44, no. 5 (October 2018): 1100–1109. http://dx.doi.org/10.1016/j.jglr.2018.07.007.

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Sullivan, S. Mažeika P., and Mary C. Watzin. "Relating stream physical habitat condition and concordance of biotic productivity across multiple taxa." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 12 (December 2008): 2667–77. http://dx.doi.org/10.1139/f08-165.

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To explore the potential of assessments of stream geomorphic condition and habitat quality in evaluating lotic productivity, we investigated concordance of stream biotic productivity (aquatic macroinvertebrates, crayfish, fish, and belted kingfishers ( Ceryle alcyon )) and their physical habitat correlates in 18 streams in the Champlain Valley, Vermont, USA. Pearson correlation analysis indicated significant concordance between macroinvertebrate density and fish biomass (r = 0.76), between the density of macroinvertebrates in the orders Ephemeroptera, Plecoptera, and Trichoptera and fish biomass (r = 0.81), and between fish biomass and kingfisher brood weight (r = 0.54). We used principal component analysis followed by linear regression to investigate relationships between physical habitat condition and biotic productivity and to identify key components of physical habitat condition assessments. Our analysis supported the combined use of geomorphic and habitat assessments as a comprehensive indicator of stream physical habitat condition. We found relationships between habitat assessment scores and productivity measures of all taxa except crayfish, suggesting similar responses to physical condition across trophic levels. Our results encourage the use of additional taxa, in addition to widely used macroinvertebrate metrics, as indicators of the composite effects of physical habitat impairment in stream ecosystems.

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Mameri, Daniel, Corina van Kammen, Ton G. G. Groothuis, Ole Seehausen, and Martine E. Maan. "Visual adaptation and microhabitat choice in Lake Victoria cichlid fish." Royal Society Open Science 6, no. 3 (March 2019): 181876. http://dx.doi.org/10.1098/rsos.181876.

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When different genotypes choose different habitats to better match their phenotypes, genetic differentiation within a population may be promoted. Mating within those habitats may subsequently contribute to reproductive isolation. In cichlid fish, visual adaptation to alternative visual environments is hypothesized to contribute to speciation. Here, we investigated whether variation in visual sensitivity causes different visual habitat preferences, using two closely related cichlid species that occur at different but overlapping water depths in Lake Victoria and that differ in visual perception ( Pundamilia spp.). In addition to species differences, we explored potential effects of visual plasticity, by rearing fish in two different light conditions: broad-spectrum (mimicking shallow water) and red-shifted (mimicking deeper waters). Contrary to expectations, fish did not prefer the light environment that mimicked their typical natural habitat. Instead, we found an overall preference for the broad-spectrum environment. We also found a transient influence of the rearing condition, indicating that the assessment of microhabitat preference requires repeated testing to control for familiarity effects. Together, our results show that cichlid fish exert visual habitat preference but do not support straightforward visual habitat matching.

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Roberts, Ryan. "New National Fish Habitat Assessment Report Provides Key Information for Fish Conservation Planning." Fisheries 42, no. 1 (January 2, 2017): 5–6. http://dx.doi.org/10.1080/03632415.2017.1262674.

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Carbajal, Soler, Tallo-Parra, Isasa, Echevarria, Lopez-Bejar, and Vinyoles. "Towards Non-Invasive Methods in Measuring Fish Welfare: The Measurement of Cortisol Concentrations in Fish Skin Mucus as a Biomarker of Habitat Quality." Animals 9, no. 11 (November 8, 2019): 939. http://dx.doi.org/10.3390/ani9110939.

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Cortisol levels in fish skin mucus have shown to be good stress indicators in farm fish exposed to different stressors. Its applicability in free-ranging animals subject to long-term environmental stressors though remains to be explored. The present study was therefore designed to examine whether skin mucus cortisol levels from a wild freshwater fish (Catalan chub, Squalius laietanus) are affected by the habitat quality. Several well-established hematological parameters and cortisol concentrations were measured in blood and compared to variations in skin mucus cortisol values across three habitats with different pollution gradient. Fluctuations of cortisol in skin mucus varied across the streams of differing habitat quality, following a similar pattern of response to that detected by the assessment of cortisol levels in blood and the hematological parameters. Furthermore, there was a close relationship between cortisol concentrations in skin mucus and several of the erythrocytic alterations and the relative proportion of neutrophils to lymphocytes. Taken together, results of this study provide the first evidence that skin mucus cortisol levels could be influenced by habitat quality. Although results should be interpreted with caution, because a small sample size was collected in one studied habitat, the measurement of cortisol in skin mucus could be potentially used as a biomarker in freshwater fish.

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Soldo, Alen, Igor Glavičić, and Marcelo Kovačić. "Combining Methods to Better Estimate Total Fish Richness on Temperate Reefs: The Case of a Mediterranean Coralligenous Cliff." Journal of Marine Science and Engineering 9, no. 6 (June 18, 2021): 670. http://dx.doi.org/10.3390/jmse9060670.

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Coralligenous habitat is considered as one of the most important special habitat types in the Mediterranean; however, due to its inaccessibility, little is known about it, although it is considered as one of the Mediterranean’s richest habitats in terms of species. Due to a low number of studies, it was presumed that the richness of coralligenous fish assemblages is underestimated using traditional visual census methods which are not applicable to the deep, steep, and vertical slopes of coralligenous cliffs and do not capture exhaustively cryptobenthic species commonly found in this habitat. This paper aims at producing a more complete assessment of fish assemblages on a coralligenous cliff by combining different methods, particularly the deep vertical transect visual census and square with anesthetics method. A total of 76 fish species were recorded on a single coralligenous cliff, supporting the opinion that coralligenous cliffs are important Mediterranean biodiversity hotspots. The analysis of species traits between species recorded by the different methods showed how complementary they are to better describe species compositions. Hence, the result of this study demonstrates that the combined use of methods is essential for a more exhaustive description of the whole fish community structure and for accurate estimates of the abundance and diversity patterns, particularly in complex habitats such as coralligenous cliffs.

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Guay, J. C., D. Boisclair, M. Leclerc, and M. Lapointe. "Assessment of the transferability of biological habitat models for Atlantic salmon parr (Salmo salar)." Canadian Journal of Fisheries and Aquatic Sciences 60, no. 11 (November 1, 2003): 1398–408. http://dx.doi.org/10.1139/f03-120.

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We assessed the transferability of the habitat suitability index (HSI) and the habitat probabilistic index (HPI) between two rivers. Transferability was measured by the ability of HSI and HPI models developed in the Sainte-Marguerite River to predict the distribution of Atlantic salmon parr (Salmo salar) in the Escoumins River. HSI and HPI were based on the pattern of utilization by fish of water depth, current velocity, and substrate size. HSI was developed using the preference curve approach, and HPI was developed using a multiple logistic regression. Predicted values of HSI and HPI in Escoumins River ranged from 0 (poor habitat) to 1 (excellent habitat). Fish density in habitat patches assigned different HSI or HPI values ranged from 0 to 1 fish·100 m–2. Only HPI adequately predicted local variations in parr density (r2 = 0.84) in habitat patches of Escoumins River. Our results suggest that HSI is less transferable between rivers than HPI. Differences in substrate size between the two rivers is suspected to impede the transferability of the HSI model. We also argue that the mathematical structure of HPI provides a larger degree of flexibility that facilitates its transferability and its potential generalization.

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Loesch, Charles R., Ronald E. Reynolds, and LeRoy T. Hansen. "An Assessment of Re-Directing Breeding Waterfowl Conservation Relative to Predictions of Climate Change." Journal of Fish and Wildlife Management 3, no. 1 (June 1, 2012): 1–22. http://dx.doi.org/10.3996/032011-jfwm-020.

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Abstract The U.S. Fish and Wildlife Service has a long history of habitat conservation in the Prairie Pothole Region (PPR) of the United States that has focused on migratory birds, particularly waterfowl. The ongoing acquisition program of the U.S. Fish and Wildlife Service National Wildlife Refuge System has conserved approximately 1.1 million hectares of critical breeding waterfowl habitat. Results of recent predicted future climate scenarios are being used to suggest that waterfowl conservation be shifted away from currently important areas in the western and central portions of the U.S. PPR eastward, to locations where wetland and climate models suggest may become more conducive for providing wetland habitat for breeding ducks in the future. We used 24 years of breeding waterfowl and wetland monitoring data collected by the U.S. Fish and Wildlife Service National Wildlife Refuge System in the PPR of North and South Dakota and northeast Montana, along with land value and restoration cost data to conduct an economic assessment of the biological risk of refocusing waterfowl conservation efforts eastward due to recent projections of climate change. We considered the immediate risk of the loss of existing wetland and grassland resources in the western portion of the U.S. PPR, their current carrying capacity and production potential, the financial cost of protection vs. restoration relative to current conservation priorities, and the uncertainty of climate change effects on waterfowl habitat distribution. Because unprotected wetland and grassland habitats exist in the western and central portions of the PPR that are important for maintaining current waterfowl carrying capacity and productivity, and climate change effects are highly uncertain, maintaining the current focus of habitat protection appears to be the most cost effective approach for waterfowl habitat conservation efforts. Additionally, continued intensive monitoring activities designed to detect changing waterfowl populations and upland and wetland habitat as they relate to anthropogenic impacts (e.g., pattern tile drainage, grassland conversion) and climatic changes (e.g., wetland hydro-period), should provide more precise results to inform and adapt management and conservation activities accordingly should spatial and temporal changes in wet-dry cycles occur in the future.

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Smokorowski, K. E., and T. C. Pratt. "Effect of a change in physical structure and cover on fish and fish habitat in freshwater ecosystems – a review and meta-analysis." Environmental Reviews 15, NA (December 2007): 15–41. http://dx.doi.org/10.1139/a06-007.

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Aquatic resource managers are continually faced with construction or site development proposals which, if allowed to proceed, would ultimately alter the physical structure and cover of fish habitat. In the absence of clear quantitative guidelines linking the change in habitat to fish, resource managers often use the change in habitat area as a basis for decisions. To assess the weight of scientific evidence in support of management decisions, we summarized both the observational and experimental freshwater fish-habitat literature. We then extracted data from experimental studies (where possible) for inclusion in a meta-analysis, to provide a more rigorous assessment of the published results of experimental habitat manipulations. We found relatively strong and consistent correlational evidence linking fish and physical habitat features, yet inconsistent evidence when narratively reviewing the experimental literature. On the whole, decreases in structural habitat complexity are detrimental to fish diversity and can change species composition. Increases in structural complexity showed increases, decreases, or no measurable changes in species and (or) communities. The majority of our meta-analyses resulted in supporting a direct link between habitat and fish abundance or biomass, with fish biomass responding most strongly to habitat change. Habitat alterations are most likely to affect individual species or community structure, and thus evaluating the extent of the effect on a biological basis depends on management objectives.

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Benfield, Sarah, Laura Baxter, Hector M. Guzman, and James M. Mair. "A comparison of coral reef and coral community fish assemblages in Pacific Panama and environmental factors governing their structure." Journal of the Marine Biological Association of the United Kingdom 88, no. 7 (July 22, 2008): 1331–41. http://dx.doi.org/10.1017/s0025315408002002.

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We compared the reef fish assemblages of two habitats, coral reefs and coral communities (rocky substratum with coral colonies), in the Las Perlas Archipelago in Pacific Panama and attempted to determine associations with habitat variables. We used a modified Atlantic and Gulf Rapid Reef Assessment (AGRRA) survey to record fish species and quadrat transects to determine benthic composition. Multivariate non-parametric multi-dimensional scaling (MDS) ordinations were performed in PRIMER and univariate correlations were used to determine relationships. The reef fish of coral communities were significantly more diverse and species rich than those of coral reefs. The two habitats had significantly different species and size composition, but trophic and family groups overlapped between habitats. Topography, exposure, and the percentage cover of branching and massive corals correlated significantly with differences in fish parameters. The reef fish assemblages of this region appear to be determined more by the larger scale structural features that characterize the two habitats than by features that vary over small scales within the habitats.

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Casatti, L., F. Langeani, A. M. Silva, and R. M. C. Castro. "Stream fish, water and habitat quality in a pasture dominated basin, southeastern Brazil." Brazilian Journal of Biology 66, no. 2b (May 2006): 681–96. http://dx.doi.org/10.1590/s1519-69842006000400012.

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A fish survey in 35 stream reaches (from 1st to 3rd order) with physicochemical and habitat assessment in the São José dos Dourados system, southeastern Brazil, was conducted. Most of the basin land cover (77.4%) is used for pasture. From the sampled stream reaches, 24 were of good physicochemical quality, 10 of fair quality, and only one of poor quality. A habitat assessment showed that 10 stream reaches were considered fair, 22 were poor, and 3 were very poor. Fifty species were collected and their abundances showed strong correlation with habitat descriptors. In addition to the correlation between fish abundance and habitat, some species also showed optimal distribution related to the degree of physical habitat conservation. Streams located in this region experience organic pollution, but the most important aspect is the decline of the instream physical habitat condition, especially in first order streams, which negatively affects coarse substrates and water column dependent fish species. Effluent control, riparian vegetation restoration programs, siltation control and adequate sustainable soil use are practices which could mitigate such impacts.

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Park, Sangyoung, Jeongkon Kim, Ick Hwan Ko, Angela Arthington, Gary Jones, and Kyung Taek Yum. "Assessment of hydraulic fish habitat condition using integrated toolkit: a case study of the Geum river basin, Republic of Korea." Water Science and Technology 62, no. 12 (December 1, 2010): 2811–18. http://dx.doi.org/10.2166/wst.2010.425.

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Artificial changes of rivers, including construction and operation of dams, inevitably lead to physical and ecological changes throughout waterways and their floodplains. In this study, a conceptual model coupled with integrated numerical modeling is presented for hydraulic fish habitat assessment of the Geum River basin, Republic of Korea. Based on the major events which might have affected the ecological system, a conceptual model was formulated to guide desktop and field studies, modeling and scenario evaluations. The result of hydraulic fish habitat assessment indicated that the construction of the Daecheong Multipurpose Dam (DMD) in the Geum River basin has altered flow magnitudes and reduced the river's flow variability. Changes are evident in the magnitude of medium and small flows and the river experiences increased low flows during the dry season. Black shiner, an endangered fish species in Korea, was selected and analyzed to explore relationships between flow regime change by dams and changes to its preferred habitats. As a result, fewer sensitive riffle-benthic species were observed in the reaches downstream of DMD due to the reduction of suitable habitat conditions such as riffle-pool sequences. The proposed conceptual model and integrated toolkit would allow river managers to isolate the physical and biological effects associated with dam operation and could be useful for developing river management strategies.

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Subarno, Tarlan, Vincentius Paulus Siregar, and Syamsul Bahri Agus. "OBIA AND BTM INTEGRATION FOR MAPPING HABITAT COMPLEXITY OF CORAL REEFS ON HARAPAN-KELAPA ISLANDS, KEPULAUAN SERIBU." Coastal and Ocean Journal (COJ) 2, no. 1 (May 10, 2018): 11–22. http://dx.doi.org/10.29244/coj.2.1.11-22.

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The habitat complexity is indirectly closely related to reef fish abundance. This study aims to map reefs habitat complexity by integrating object-based image analysis (OBIA) and habitat complexity analysis using benthic terrain modeler (BTM). The datasets used were SPOT-7 imagery and water depth derived from satellite imagery. The ground check was conducted to collect field data used as reference for classification and accuracy assessment of classification results. Classification of SPOT-7 imagery was performed using support vector machines (SVM) algorithm, by grouping shallow waters habitats into 4 classes on level 2 and 3 classes on level 3. Accuracy assessment was done by confusion matrix and resulting overall accuracy (OA) 83.55% for level 2 and 79.66% for level 3. The habitat complexity was analyzed using rugosity analysis method (Arc-Chord Ratio) from benthic terrain modeler (BTM) to obtain rugosity index in reefs area. The substrate covers were obtained from OBIA and complexity of habitats were obtained from BTM, then the overlay result shows varying rugosity index on the reef area in Harapan-Kelapa Islands. Keywords: coral reefs, OBIA, habitat complexity, rugosity

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Nandy, Vaswati, Madhurima Bakshi, Somdeep Ghosh, Harish Sharma, Barnali Ray Basu, and Punarbasu Chaudhuri. "Potentiality Assessment of Fish Scale Biodegradation Using Mangrove Fungi Isolated from Indian Sundarban." International Letters of Natural Sciences 14 (April 2014): 68–76. http://dx.doi.org/10.18052/www.scipress.com/ilns.14.68.

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The mangrove fungi, morphologically and physiologically adapted in a different habitat, were isolated from mangrove habitat of Jharkhali, Sundarban, India. The physico-chemical properties like temperature, pH, soil colour, moisture content, carbon and nitrogen content of soil determines the load of microbial population. The soil sample was serially diluted and plated on potato dextrose agar plate with ampicillin to obtain fungal isolates. Total of six isolates were characterized microscopically by lacto phenol cotton blue staining. Two of them were identified as Aspergillus niger and Penicillium sp. and are subjected to biodegradation of fish scale, the major waste of fish processing industries. Aspergillus niger was found to be the best for degradation of fish scale powder by producing zone of clearance. Moreover, media without fish scale didn’t show any zone of clearance indicates the mangrove fungi are capable of degrading the fish scale component

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Quist, Michael C., Wayne A. Hubert, Mark Fowden, Steven W. Wolff, and Michael R. Bower. "Feature - Fish Habitat - The Wyoming Habitat Assessment Methodology (WHAM): A Systematic Approach to Evaluating Watershed Conditions and Stream Habitat." Fisheries 31, no. 2 (February 2006): 75–81. http://dx.doi.org/10.1577/1548-8446(2006)31[75:ffhtwh]2.0.co;2.

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Rooper, Christopher N., Gerald R. Hoff, and Alex De Robertis. "Assessing habitat utilization and rockfish (Sebastes spp.) biomass on an isolated rocky ridge using acoustics and stereo image analysis." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 10 (October 2010): 1658–70. http://dx.doi.org/10.1139/f10-088.

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For those marine fish species with specific habitat preferences, a habitat-based assessment may provide an alternative to traditional surveys. We conducted a habitat-based acoustic and stereo image stock assessment survey for rockfishes (Sebastes spp.) on a rocky ridge habitat in the eastern Bering Sea. Video analysis suggested that juvenile and adult rockfishes were more abundant on the seafloor in the rocky ridge area than on the surrounding sandy flats. Over the ridges, the distribution of rockfishes was uniformly low in the water column during nighttime surveys and higher during daytime surveys. The opposite pattern was observed in the video on the seafloor between night (high density) and day (lower density), indicating that fish in the water column during the day moved to the seafloor at night. Mean biomass of adult rockfishes for the rocky ridges was 1.54 × 104 tonnes based on acoustic data. The biomass of juvenile fish was estimated to be 9.2 × 102 tonnes. Utilization of similar survey methodologies on a larger scale might improve assessment of rockfishes not only in Alaska, but also throughout their range where fishery-independent biomass estimates have been difficult to obtain.

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QUIST, M. C., W. A. HUBERT, and F. J. RAHEL. "Concurrent assessment of fish and habitat in warmwater streams in Wyoming." Fisheries Management and Ecology 13, no. 1 (February 2006): 9–20. http://dx.doi.org/10.1111/j.1365-2400.2006.00463.x.

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Marshall, Kristin N., Laura E. Koehn, Phillip S. Levin, Timothy E. Essington, and Olaf P. Jensen. "Inclusion of ecosystem information in US fish stock assessments suggests progress toward ecosystem-based fisheries management." ICES Journal of Marine Science 76, no. 1 (October 25, 2018): 1–9. http://dx.doi.org/10.1093/icesjms/fsy152.

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Abstract The appetite for ecosystem-based fisheries management (EBFM) approaches has grown, but the perception persists that implementation is slow. Here, we synthesize progress toward implementing EBFM in the United States through one potential avenue: expanding fish stock assessments to include ecosystem considerations and interactions between species, fleets, and sectors. We reviewed over 200 stock assessments and assessed how the stock assessment reports included information about system influences on the assessed stock. Our goals were to quantify whether and how assessments incorporated broader system-level considerations, and to explore factors that might contribute to the use of system-level information. Interactions among fishing fleets (technical interactions) were more commonly included than biophysical interactions (species, habitat, climate). Interactions within the physical environment (habitat, climate) were included twice as often as interactions among species (predation). Many assessment reports included ecological interactions only as background or qualitative considerations, rather than incorporating them in the assessment model. Our analyses suggested that ecosystem characteristics are more likely to be included when the species was overfished (stock status), the assessment is conducted at a science centre with a longstanding stomach contents analysis program, and/or the species life history characteristics suggest it is likely to be influenced by the physical environment, habitat, or predation mortality (short-lived species, sessile benthic species, or low trophic-level species). Regional differences in stomach contents analysis programs may limit the inclusion of predation mortality in stock assessments, and more guidance is needed on best practices for the prioritization of when and how biophysical information should be considered. However, our results demonstrate that significant progress has been made to use best available science and data to expand single-species stock assessments, particularly when a broad definition of EBFM is applied.

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Dai, Dongchen, Hongwei Fang, Songheng Li, Guojian He, Lei Huang, and Wenqi Peng. "Numerical simulation of fish movement behavior for habitat assessment by Eulerian-Eulerian-Habitat-Selection (EEHS) method." Ecological Modelling 337 (October 2016): 156–67. http://dx.doi.org/10.1016/j.ecolmodel.2016.06.016.

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Minns, Charles K., Robert G. Randall, Karen E. Smokorowski, Keith D. Clarke, Antonio Vélez-Espino, Robert S. Gregory, Simon Courtenay, and Patrice LeBlanc. "Direct and indirect estimates of the productive capacity of fish habitat under Canada’s Policy for the Management of Fish Habitat: where have we been, where are we now, and where are we going?" Canadian Journal of Fisheries and Aquatic Sciences 68, no. 12 (December 2011): 2204–27. http://dx.doi.org/10.1139/f2011-130.

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No net loss of productive capacity (PC) of fish habitat has been the central concept guiding Canadian fish habitat management policy since 1986. The purpose of this paper is to describe the concept of PC, to review the history and application of the fish habitat management policy in Canada, and to provide a critical review of the range of potential approaches to estimating PC. The approaches were grouped by their central focus: habitat, individual, population, and community–ecosystem. A set of case studies is used to illustrate the use of some approaches drawn from freshwater and marine contexts. Ten components to assessing no net loss of PC were developed and used in the review of approaches for evaluating potential limitations. The review also highlighted the likely future direction of method development, with increasing emphasis on dynamic models integrating population responses to habitat supply characteristics. More work needs to be done to turn research-based metrics of PC into practical operational management assessment tools and to better quantify the link between habitat structure and function and fisheries productivity. The evolving approaches to measure PC reinforce the ties that fish habitat management has to the emerging practices in ecosystem-based management.

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Oh, Kukryul, Jooheon Lee, Christabel J. Rubio, Leehyung Kim, and Sangman Jeong. "Assessment of aquatic habitat effect by artificial change of streambed topography." Water Science and Technology 62, no. 12 (December 1, 2010): 2872–79. http://dx.doi.org/10.2166/wst.2010.226.

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As interest in ecosystems and the environment has recently increased, efforts for the preservation and restoration of river ecosystems have increased. The purpose of this study is to estimate the fish physical habitat by artificial change of streambed topography applying two-dimensional simulation model, River2D. A total reach length of 130 m along the Je stream located within the Geum River basin in Korea was used in this study. The target fish is the dominant fish species, Zacco platypus, which was evaluated for two growth steps (adult and spawning). Five scenarios were considered which included the installation of small dams at three different heights (0.25 m, 0.50 m, and 1.00 m) and installation of small pool with 0.25 m and 0.50 m depth. Results indicated that for natural streambed conditions the adult optimum flow was 1 m3/s, and the spawning optimum flow was 3 m3/s. The mean annual outflow for the natural condition was 0.64 m3/s, lower than the evaluated optimum flows. Applying the three discharges observed in 2008 to the five scenarios, the installation of the small dam increased the weighted usable area (WUA) while the installation of pools decreased the WUA, both as compared to the WUA for the natural condition.

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Mendonça-Neto, José Policarpo de, Cassiano Monteiro-Neto, and Luiz Eduardo Moraes. "Reef fish community structure on three islands of Itaipu, Southeast Brazil." Neotropical Ichthyology 6, no. 2 (2008): 267–74. http://dx.doi.org/10.1590/s1679-62252008000200015.

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We provide here the first assessment of the composition, abundance and distribution of rocky reef fishes of Itaipu Sound, Rio de Janeiro, off the southeastern Brazilian coast. Monthly visual censuses, benthic quadrats and chain link transects were conducted over one year on rocky reefs at three islands (Menina, Mãe and Pai). A total of 2466 individual fish, belonging to 29 families and 42 species were recorded. The most abundant fish species were Parablennius pilicornis, Haemulon steindachneri, Orthopristis ruber and Diplodus argenteus. Sheltered and complex habitats showed the most abundant and diverse fish populations. There was a major significant separation between sampling sites and a secondary seasonal pattern. The three sites showed similar fish communities with locally structured environmental gradients according to their inherent habitat characteristics.

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Santos, Alejandra F. G. N., Carles Alcaraz, Luciano N. Santos, Carmino Hayashi, and Emili García-Berthou. "Experimental assessment of the effects of a Neotropical nocturnal piscivore on juvenile native and invasive fishes." Neotropical Ichthyology 10, no. 1 (2012): 167–76. http://dx.doi.org/10.1590/s1679-62252012000100016.

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We experimentally examined the predator-prey relationships between juvenile spotted sorubim Pseudoplastystoma corruscans and young-of-the-year invasive and native fish species of the Paraná River basin, Brazil. Three invasive (peacock bass Cichla piquiti, Nile tilapia Oreochromis niloticus, and channel catfish Ictalurus punctatus) and two native (yellowtail tetra Astyanax altiparanae and streaked prochilod Prochilodus lineatus) fish species were offered as prey to P. corruscans in 300 L aquaria with three habitat complexity treatments (0%, 50% and 100% structure-covered). Prey survival was variable through time and among species (C. piquiti < O. niloticus < A. altiparanae < P. lineatus < I. punctatus), depending largely on species-specific prey behavior but also on prey size and morphological defenses. Habitat complexity did not directly affect P. corruscans piscivory but some prey species changed their microhabitat use and shoaling behavior among habitat treatments in predator's presence. Pseudoplatystoma corruscans preyed preferentially on smaller individuals of those invasive species with weak morphological defensive features that persisted in a non-shoaling behavior. Overall, our results contrast with those in a companion experiment using a diurnal predator, suggesting that nocturnal piscivores preferentially prey on different (rather diurnal) fish species and are less affected by habitat complexity. Our findings suggest that recovering the native populations of P. corruscans might help controling some fish species introduced to the Paraná River basin, particularly C. piquiti and O. niloticus, whose parental care is expected to be weak or null at night.

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Guareschi, Simone, Alex Laini, Pierluigi Viaroli, and Rossano Bolpagni. "Integrating habitat- and species-based perspectives for wetland conservation in lowland agricultural landscapes." Biodiversity and Conservation 29, no. 1 (October 17, 2019): 153–71. http://dx.doi.org/10.1007/s10531-019-01876-8.

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Abstract Wetlands are among the most endangered ecosystems worldwide with multiple direct and indirect stressors, especially in human-altered areas like intensive agricultural landscapes. Conservation management and efforts often focus on species diversity and charismatic taxa, but scarcely consider habitats. By focusing on a complex formed by 107 permanent wetlands at 18 Natura 2000 sites in the Emilia-Romagna region (northern Italy), the patterns of habitats of conservation concern were investigated and the concordance with threatened species patterns was analysed. Wetlands were characterised in terms of morphology, connectivity, land use and management as drivers of assemblage and richness patterns of habitats. Our results showed a strong concordance between the distribution and richness patterns of both habitats and threatened taxa (birds, mammals, amphibians, reptiles, fish, invertebrates, and plants). Thus, habitats seem an effective proxy of species patterns. The variables related with perimeter, environmental heterogeneity and presence of water bodies were the most important ones associated with habitat richness patterns. The presence of aquatic systems (measured as the percentage of wetland area occupied by an aquatic surface) and their position in the hydrographic network were associated mostly with habitats distribution. Low richness wetlands (in habitat terms) were not complementary as no new habitat types were supported. The results stressed the relevance of wetlands with wide water body perimeters composed of diverse systems as being key for biodiversity conservation in a simplified agricultural matrix. Integrating habitat- and species-based perspectives seems a promising field and may provide a rapid assessment tool to acquire effective information for wetlands conservation and assessment.

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Swanson, S. M., R. Schryer, R. Shelast, P. J. Kloepper-Sams, and J. W. Owens. "Exposure of fish to biologically treated bleached-kraft mill effluent. 3. Fish habitat and population assessment." Environmental Toxicology and Chemistry 13, no. 9 (September 1994): 1497–507. http://dx.doi.org/10.1002/etc.5620130912.

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Choi, Byungwoong, and Seung Se Choi. "Integrated Hydraulic Modelling, Water Quality Modelling and Habitat Assessment for Sustainable Water Management: A Case Study of the Anyang-Cheon Stream, Korea." Sustainability 13, no. 8 (April 13, 2021): 4330. http://dx.doi.org/10.3390/su13084330.

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Recent ecological stream restoration projects have focused on expanding the water-friendly space of streams, promoting the health of aquatic ecosystems, and restoring various habitats, which raise the need for relevant research. Applying integrated environmental analysis, this study quantifies the change in hydraulic characteristics before and after the restoration projects through physical habitat simulation and links the results of physical impacts to estimate benefits of increase in water quality and aquatic ecosystem health due to the implementation of the project. For this, the study area is a 3.3 km long reach of the Anyang-cheon Stream, Korea. Field monitoring revealed that five fish species are dominant and sub-dominant, and account for 76% of the total fish community. To assess the change of before and after ecological stream restoration project, the River2D and Coastal Modelling System (CMS)-Flow 2D models were used for hydraulic and water quality simulations, respectively. For the habitat simulation, the HSI (Habitat Suitability Index) model was used. In addition, the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was used to calculate changes in water quality index and to examine changes in habitat areas with an integrated quantitative index, the methodology of Zingraff-Hamed et al. was adopted. It was found that the ecological stream restoration project significantly increased for the eco-friendly area. In addition, the changes in water quality and habitat suitability grades before the ecological river restoration project were improved to two stages and one stage, respectively. This study applied the integrated analytical framework as a policy/project assessment tool and the results of this study will be useful for the integrated water management policy.

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Hinch, Scott G., Keith M. Somers, and Nicholas C. Coliins. "Spatial Autocorrelation and Assessment of Habitat–Abundance Relationships in Littoral Zone Fish." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 3 (March 1, 1994): 701–12. http://dx.doi.org/10.1139/f94-070.

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Spatial autocorrelation, wherein intersite similarity is correlated with distance between sites, is a characteristic of most ecological studies spanning a large environmental range. If data are spatially autocorrelated, classical statistical techniques provide biased estimates of relationships between species attributes and environmental variables. We examined abundances of seven littoral fishes in 25 lakes that varied substantially in morphometry, chemistry, and elevation across central Ontario. Weak correlations were observed between abundances of particular species and environmental variables before correcting for spatial autocorrelation, and we hypothesized that correlations reflected species' habitat preferences. However, spatial autocorrelation existed in the abiotic and fish abundance datasets. Once large-scale geographic patterns (spatial autocorrelation) were removed using partial Mantel tests, correlations changed within and between datasets. A strong relationship emerged between abundances and lake elevation. By comparing patterns within geographically corrected data with those without correction, we identified particular species that exhibited spatially autocorrelated abundances. The geographic direction of spatial autocorrelation provided additional insights into environmental factors also correlating with species abundance. We recommend that ecologists examine both geographically corrected and noncorrected data when developing hypotheses to explain regional variation in species abundance.

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Clua, Eric, Pierre Legendre, Laurent Vigliola, Franck Magron, Michel Kulbicki, Sébastien Sarramegna, Pierre Labrosse, and René Galzin. "Medium scale approach (MSA) for improved assessment of coral reef fish habitat." Journal of Experimental Marine Biology and Ecology 333, no. 2 (June 2006): 219–30. http://dx.doi.org/10.1016/j.jembe.2005.12.010.

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Kallasvuo, Meri, Jarno Vanhatalo, and Lari Veneranta. "Modeling the spatial distribution of larval fish abundance provides essential information for management." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 5 (May 2017): 636–49. http://dx.doi.org/10.1139/cjfas-2016-0008.

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Productive fisheries are strongly linked to the ecological state of the essential habitats. In this study, we developed a methodology to assess the most important reproduction habitats of fish by using larval survey data and Bayesian species distribution models that predict the spatial distribution and abundance of fish larvae. Our case study with four commercially and ecologically important fish species in the coastal zone of the northern Baltic Sea demonstrated that the production of fish stocks can be concentrated to an extremely limited area compared with the entire suitable production area. The area suitable for larval production varied from 3.7% to 99.8% among species, but the smallest area responsible for 80% of the cumulative larval production was two to five times more limited, varying from 1.4% to 52.9% among species. Hence, instead of the traditional approach of modeling only habitat suitability for fish production, marine spatial planning and management should take into account the areal production potential. Moreover, the developed methodology enables linking of the total production potential across the whole distribution area to fisheries stock assessment and management.

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DiPinto, Lisa, Tony Penn, John Iliff, and Charles Peterson. "DETERMINING THE SCALE OF RESTORATION FOR A FISH KILL IN THE ALAFIA RIVER, FLORIDA1." International Oil Spill Conference Proceedings 2001, no. 2 (March 1, 2001): 1511–16. http://dx.doi.org/10.7901/2169-3358-2001-2-1511.

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ABSTRACT In December 1997, a phosphogypsum stack wall failed at a phosphoric acid/ fertilizer production facility in Mulberry, Florida, releasing 50–56 million gallons of acidic process water into the Alafia River, a major tributary of Tampa Bay. The process water lowered the pH along 35 miles of the river to levels ranging from approximately 2.3 in the freshwater portion to 3–4 in the lower 10-mile estuarine portion. This release resulted in a significant fish kill and injuries to other natural resources and services. This paper describes the fish kill assessment and the determination of restoration type and scale to offset the fish injuries. The assessment team quantified the fish kill as total biomass lost, defined as the sum of direct mortality plus the foregone future production, as loss of somatic growth of those individuals that were killed. The team identified creation and/or enhancement of fish habitats as the preferred alternatives to provide fish production of the species that were injured, which is an established approach to compensate for acute, species-specific losses. Case-specific analytic techniques were used to estimate secondary productivities from the preferred habitats. Based on the productivity data, the assessment team calculated the scale of the habitat projects that, over the course of their lifetimes, would provide the same amount of biomass that was lost. While the injuries were the result of a hazardous substance release, as opposed to an oil spill, the methods used for injury determination and restoration scaling are directly applicable to an oil spill scenario.

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Kim, Jung-Jae, Usman Atique, and Kwang-Guk An. "Long-Term Ecological Health Assessment of a Restored Urban Stream Based on Chemical Water Quality, Physical Habitat Conditions and Biological Integrity." Water 11, no. 1 (January 10, 2019): 114. http://dx.doi.org/10.3390/w11010114.

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We studied the chemical water quality, physical habitat and biotic integrity of an urban stream subjected to restoration measures in South Korea. We used the water pollution index (WPI), qualitative habitat evaluation index (QHEI) and index of biotic integrity (IBI) on the water quality, physical habitat and fish assemblage data respectively, during 2007–2016 in Gap Stream to evaluate the ecological health before and after restoration measures. The results revealed annual mean total phosphorus (TP) dramatically decreased by 13-fold for 10 years and the values of biological oxygen demand (BOD) and chemical oxygen demand (COD) also decreased by >50% over the time, indicating decrease in nutrient enrichment and organic matter pollution after restoration measures. In the meantime, biological health analyses using IBI indicated no major transformation in fish assemblages under restoration impact. However, the proportion of sensitive species increased, and tolerant species decreased after restoration. Gap stream is home to 50 distinct fish species. QHEI proposed that the physical habitat health was in ‘good’ condition during the study period. WPI showed the chemical water quality status remained ‘poor’ during and before restoration but improved to ‘fair-good’ condition in the ensuing years after restoration. The IBI results, however, indicated ‘very poor-poor’ biotic integrity irrespective of restoration measures. CHL-a and TP showed strong (r < 0.7) to moderately strong (r = 0.5–0.7) correlation with significantly important water quality factors. Spatially significant pattern change in TN and TP was obvious as measured levels were significantly higher (p < 0.01) in downstream than upstream. Principal component analysis successfully indicated the placement of water quality factors and indices used as in three distinct stream compartments. The higher pollutant levels in the downstream mainly linked to the nutrient-rich effluents from emerging from the wastewater treatment plants (WWTPs) and industrial complexes operative in the stream catchment. Overall, restoration measures indicated minor impact on fish assemblages and physical habitat due to slow and steady improvement, however, water quality improved due to a decline of nutrients and chemicals downstream. This indicated a positive tendency of improvements in physical habitat and richness of fish assemblages in Gap Stream.

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Macura, Viliam, Zuzana Š. Štefunková, Martina Majorošová, Peter Halaj, and Andrej Škrinár. "Influence of discharge on fish habitat suitability curves in mountain watercourses in IFIM methodology." Journal of Hydrology and Hydromechanics 66, no. 1 (March 1, 2018): 12–22. http://dx.doi.org/10.1515/johh-2017-0044.

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Abstract In this study, the quality of the aquatic habitats of mountain and piedmont streams was evaluated using the ‘Instream Flow Incremental Methodology (IFIM)’ decision-making tool. The quality of habitats was interpreted from the behaviour of bioindicators in the form of habitat suitability curves (HSCs). From 1995 until the present, 59 different reaches of 43 mountain streams in Slovakia and 3 validation reaches were evaluated, and the results analysed. The aim of this study was to generalize the parameters of the HSCs for the brown trout. The generalized curves will be useful for water management planning. It is difficult and time-consuming to take hydrometrical and ichthyological measurements at different water levels. Therefore, we developed a methodology for modifying suitability curves based on an ichthyological survey during a low flow and a flow at which fish lose the ability to resist the flow velocity. The study provides the information how such curves can be modified for a wider flow range. In summary, this study shows that generalized HSCs provide representative data that can be used to support both the design of river restoration and the assessment of the impacts of the water use or of climate change on stream habitat quality.

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Ahmad, Aditiyawan. "RESPON IKAN KARANG PADA AREA APARTEMEN IKAN DI PERAIRAN TOBOLOLO DAN GAMALAMA KOTA TERNATE." Coastal and Ocean Journal (COJ) 1, no. 1 (June 14, 2017): 1–6. http://dx.doi.org/10.29244/coj.1.1.1-6.

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Fish apartment is a management actions to maintain the presence of coral fish that serves as a new habitat well as shelter and spawning. The number of fish apartment at each location is 20 units. The present study aimed at assessment the response of coral fish to the fish apartment based on the species and number of individuals coral fish. Total species found in the area of fish apartment as much as 7 families and 9 species with a total of 241 individual coral fish in the Tobololo, while 12 families and 23 species with a total of 567 individual. Moreover, the juvenile of coral fish is not identified with a size of 2-3 cm, the number of individuals in Tobololo 154 and 275 in Gamalama. The response of coral fish positively to the fish apartment evidenced by an increase in abundance and the percentage of the number and types of coral fish. So that management action with fish apartment approach provides a positive impact on the presence of coral fish as a new habitat and supports the corals juvenile.

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Vriese, F. T., S. Semmekrot, and A. J. P. Raat. "Assessment of Spawning and Nursery Areas in the River Meuse." Water Science and Technology 29, no. 3 (February 1, 1994): 297–99. http://dx.doi.org/10.2166/wst.1994.0124.

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In commission of Rijkswaterstaat Directorate Limburg, a desk study was carried out by the OVB to assess whether fish species in the river Meuse are restricted in their abundance and distribution by the lack of appropriate spawning habitat. The area studied comprises the Dutch part of the river between Eijsden and Hedel, including old river arms and former gravel pits connected with the main stream. Not included in the study is the Grensmaas, a non-canalised stretch of the river. A total of 21 fish species were selected, whose habitat requirements regarding spawning and growth were collected by a literature survey. The assessment was made by relating habitat-associated factors (water depth, rate of flow, substratum, macrophytes) with fish-specific requirements on spawning and growth. Thus it was possible to assess per river section of 100 meters length its potential suitability as spawning and nursery area for 17 species. It was concluded that no potential spawning and nursery areas are available for barbel (Barbus barbus), chub (Leuciscus cephalus), nose carp (Chondrostoma nasus) and dace (Leuciscus leuciscus). The presence of these species in the study area can be explained by migration out of the Grensmaas. Only on 1.5 % of the total amount of river sections macrophytes are present, which obviously limits the possibilities for the phytophilic species pike (Esox lucius), tench (Tinca tinca), crucian carp (Carassius carassius), carp (Cyprinus carpio), bitterling (Rhode us sericeus amarus), white bream (Blicca bjoerkna) and rudd (Scardinius erythrophthalmus). For ide (Leuciscus idus), gudgeon (Gobio gobio), bleak (Alburnus alburnus), perch (Perca fluviatilis), pikeperch (Stizostedion hicioperca) and ruffe (Gymnocephalus cernua) potential spawning and nursery areas are abundantly present.

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Lazzarini Wolff, Luciano, and Norma Segatti Hahn. "Fish habitat associations along a longitudinal gradient in a preserved coastal Atlantic stream, Brazil." Zoologia 34 (December 18, 2017): 1–13. http://dx.doi.org/10.3897/zoologia.34.e12975.

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Habitat conditions at multiple scales are one of the major factors structuring ichthyofauna. Thus, we analyzed the fish habitat associations along the headwater-mouth gradient of a coastal Atlantic stream. We categorized the sampling sites into habitat units, so that in the middle reach these categories were statistically differentiated into riffles, runs and pools. Samplings were carried out quarterly from May 2009 to February 2010 using electrofishing. Principal component analysis (PCA) indicated an environmental gradient from higher water velocity and rocky bottom to deeper and sandy areas in the headwater-mouth direction. A total of 1,495 individuals belonging to 27 species were captured, being 13, 18 and 22 from headwater, middle and mouth reaches, respectively. Shannon diversity was slightly higher in the middle reach, while beta diversity showed higher rates of addition than turnover in species along the longitudinal gradient. Fish structure, evaluated by DCA (detrended correspondence analysis) scores, showed significant differences between upper reaches and mouth reach, but the middle riffles did not differ from headwater habitats. In the middle reach, mesohabitat analysis distinguished riffles, with higher abundance of fast-water crenuchids, from pools, with a higher abundance of lentic-water characids. These results suggest that environmental differences along the stream determine the wider structural patterns. However, the middle reach amassed species from upper areas and lowlands in structured fish mesohabitat associations, possibly implying distinct local ecological interactions. These findings contribute to the assessment of stream conservation status and to recognize eventual direct impacts on fish structures along longitudinal gradients.

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Katopodis, C., and H. K. Ghamry. "Hydrodynamic and physical assessment of ice-covered conditions for three reaches of the Athabasca River, Alberta, Canada." Canadian Journal of Civil Engineering 34, no. 6 (June 1, 2007): 717–30. http://dx.doi.org/10.1139/l07-026.

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Water is needed for oil sand developments in the lower Athabasca River basin of northern Alberta, Canada, and is also a key consideration from an ecological and fish habitat perspective, particularly in winter when river flows are at their lowest. Efforts to establish an appropriate flow management regime for the lower Athabasca included revision of River2D, a fixed bed, depth-averaged finite element model, available from www.river2d.ca, to predict hydraulics with a partial or total ice cover. Hydrometric surveys from three reaches of the Athabasca River were used to test the model, assess different model calibration methods, and simulate hydrodynamics for ice-covered conditions. Calibrating bed roughness from ice-free data, assuming the same bed roughness for ice-covered conditions, or the reverse, provided a close fit to the surveyed water surface elevations. The applied ice and composite roughness heights differed according to the applied method of calibration. This may have implications for local velocity estimates possibly affecting fish habitat suitability. A range of bed and composite grain roughness heights, corresponding to different bed substrates and ratios of bed and composite roughness heights to water depths, are provided for model calibration purposes. Key words: hydrodynamics, hydraulics, ice, ecology, environment, fish habitat, winter, oil sands.

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Teresa, Fabrício Barreto, and Lilian Casatti. "Development of habitat suitability criteria for Neotropical stream fishes and an assessment of their transferability to streams with different conservation status." Neotropical Ichthyology 11, no. 2 (June 2013): 395–402. http://dx.doi.org/10.1590/s1679-62252013005000009.

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We assessed the preference of 10 fish species for depth and velocity conditions in forested streams from southeastern Brazil using habitat suitability criteria (HSC curves). We also tested whether preference patterns observed in forested streams can be transferred to deforested streams. We used data from fish sampled in 62 five-meter sites in three forested streams to construct preference curves. Astyanax altiparanae, A. fasciatus, Knodus moenkhausii, and Piabina argentea showed a preference for deep slow habitats, whereas Aspidoras fuscoguttatus, Characidium zebra, Cetopsorhamdia iheringi, Pseudopimelodus pulcher, and Hypostomus nigromaculatus showed an opposite pattern: preference for shallow fast habitats. Hypostomus ancistroides showed a multimodal pattern of preference for depth and velocity. To evaluate whether patterns observed in forested streams may be transferred to deforested streams, we sampled 64 five-meters sites in three deforested streams using the same methodology. The preference for velocity was more consistent than for depth, as success in the transferability criterion was 86% and 29% of species, respectively. This indicates that velocity is a good predictor of species abundance in streams, regardless of their condition

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Davey, Andrew J. H., Douglas J. Booker, and David J. Kelly. "Diel variation in stream fish habitat suitability criteria: implications for instream flow assessment." Aquatic Conservation: Marine and Freshwater Ecosystems 21, no. 2 (January 21, 2011): 132–45. http://dx.doi.org/10.1002/aqc.1166.

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Kang, Hyeongsik, and Jun Wook Hur. "Aquatic Ecosystem Assessment and Habitat Improvement Alternative in Hongcheon River using Fish Community." Journal of The Korean Society of Civil Engineers 32, no. 5B (September 15, 2012): 331–43. http://dx.doi.org/10.12652/ksce.2012.32.5b.331.

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Boavida, I., J. M. Santos, R. V. Cortes, A. N. Pinheiro, and M. T. Ferreira. "Assessment of instream structures for habitat improvement for two critically endangered fish species." Aquatic Ecology 45, no. 1 (August 27, 2010): 113–24. http://dx.doi.org/10.1007/s10452-010-9340-x.

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Contente, R. F., M. F. Stefanoni, and H. L. Spach. "Feeding ecology of the Brazilian silverside Atherinella brasiliensis (Atherinopsidae) in a sub-tropical estuarine ecosystem." Journal of the Marine Biological Association of the United Kingdom 91, no. 6 (July 14, 2010): 1197–205. http://dx.doi.org/10.1017/s0025315410001116.

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The feeding ecology of the Brazilian silverside, Atherinella brasiliensis, in a sub-tropical estuary of Brazil was investigated through the gut analysis of 1431 individuals. We described dietary composition and analysed seasonal, estuarine habitat, and body size variations in the diet; trophic level; feeding diversity; and gut fullness indices. Results reveal that A. brasiliensis is a typical, generalistic and opportunistic predator that makes use of a wide array of prey types (at least 89 different types), with zooplankton (mainly calanoids), diatoms, terrestrial insects, and plant detritus making up the bulk of the overall diet. The exotic calanoid Temora turbinata ranked as the primary prey. A wide feeding diversity (mean H′ = 2.26), low trophic level (mean TROPH = 2.57), and high gut replenishment were persistent across seasons and habitats. Diet composition varied largely and significantly with respect to habitat, season, and body size. A closer assessment showed that habitat and season had a stronger effect on diet than fish size.

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MacRae, Pamela SD, and Donald A. Jackson. "The influence of smallmouth bass (Micropterus dolomieu) predation and habitat complexity on the structure of littoral zone fish assemblages." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 2 (February 1, 2001): 342–51. http://dx.doi.org/10.1139/f00-247.

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Fish assemblages in small lakes ([Formula: see text]50 ha) in central Ontario were characterized to determine the impact of smallmouth bass (Micropterus dolomieu) predation and habitat complexity on the structure of littoral zone fish assemblages. Data were collected employing minnow traps and visual assessment. Although species richness did not differ between lakes with and without smallmouth bass, species composition and relative abundance did differ. We identified two distinct fish assemblage types: one characterized by small-bodied species, mainly cyprinids, and a second by large-bodied centrarchid species, e.g., smallmouth bass. Smallmouth bass appear to reduce abundance, alter habitat use, and extirpate many small-bodied species such as brook stickleback (Culaea inconstans), fathead minnow (Pimephales promelas), pearl dace (Margariscus margarita), and Phoxinus spp.

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Glavičić, Igor, Marcelo Kovačić, Alen Soldo, and Ulrich Schliewen. "A quantitative assessment of the diel influence on the cryptobenthic fish assemblage of the shallow Mediterranean infralittoral zone." Scientia Marina 84, no. 1 (March 3, 2020): 49. http://dx.doi.org/10.3989/scimar.04994.21a.

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Cryptobenthic fishes are an underestimated and probably important component of coastal marine ecosystems that are usually overlooked by standard methods for collecting and studying benthic fishes. Studies focusing on cryptobenthic fishes have been rare and all have been based on samples taken during daytime. The present study tested the difference in epibenthic and cryptobenthic fish composition, diel differences in cryptobenthic fish assemblage and diel shifts of infralittoral fish species between hidden and open bottom spaces. It also looked for the significant habitat variables structuring the cryptobenthic fish assemblage. The daylight, sunset and night samples of epibenthic and cryptobenthic fish assemblages were collected from 78 squares of 1 m2 shallow water plots (0.5 to 3 m) on Brač island in the eastern Adriatic. The study recorded 27 species, among which the family Gobiidae dominated fish diversity with 14 species. Cryptobenthic specimens highly outnumbered epibenthic specimens, with a ratio of 7.5 to 1. Species composition of cryptobenthic and epibenthic fish assemblages differed significantly. No diel variation in composition, species richness or abundance of the cryptobenthic fish assemblage was detected. Occurrence frequencies in hidden and open bottom spaces of ambivalent species did not change significantly between times of day, so no dial switches between open and hidden places were apparent. In combination, these results suggest that the cryptobenthic fish assemblage has diel stability and is mostly composed of permanent inhabitants of hidden spaces with domination of miniature gobies. Significant habitat variables for species occurrence were the presence of multiple layers, bottom inclination and the presence of cobbles, while depth also had a large but not significant effect.

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Journal articles on the topic 'Fish habitat assessment'

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