A data set assembled from published literature supported the hypotheses that (i) home range size increases allometrically with body in temperate freshwater fishes, and (ii) fish ranges are larger lakes than rivers. The allometric model fitted was = A∙(body size) B . Home were 19–23 times those Additional analyses showed membership different taxonomic groupings of fish, presence–absence piscivory, method measuring range, latitude position water bodies not significant predictive factors....

ABSTRACT Climate change will ultimately affect the supply and quality of freshwater lakes rivers throughout world. This study examines potential impacts climate on fish distributions in Canada. normals data (means from 1961 to 1990) Environment Canada were used map current found tertiary watersheds Logistic regressions based these develop predictive presence‐absence equations for (a) common commercially recreationally important species (b) an Arctic a conservation significance listed by...

Abstract Predicted increases in water temperature response to climate change will have large implications for aquatic ecosystems, such as altering thermal habitat and potential range expansion of fish species. Warmwater species, smallmouth bass, Micropterus dolomieu , may access additional favourable under increased surface‐water temperatures, thereby shifting the northern limit distribution species further north Canada potentially negatively impacting native communities. We assembled a...

Karr's Index of Biotic Integrity (IBI) approach provides a biological measure ecosystem health using wide spectrum metrics which can be extracted from fish catch data obtained standardized methods. Extensive electrofishing surveys littoral assemblages, conducted in three Great Lakes' Areas Concern, provided the basis for developing lacustrine IBI that was 12 broad types: (i) species composition, (ii) trophic and (iii) abundance condition. In contrast with lotic IBIs where diversity have...

Community fish production data were summarized from the literature to test hypothesis that is higher in rivers than lakes. Average community at 55 river sites was three times greater (273 kg∙ha −1 ∙year ) 22 lakes (82 ). Higher (P) resulted much densities of (14 times) and biomass (B) (about 2 times). weight P/B ratios inversely correlated. 7 less, 1.5 (after correction for size), Thus, not only had average biomasses but also turnover rate greater. Fish positively correlated with phosphorus...

An index of fish production was significantly higher in littoral habitats with abundant submerged macrophytes, as measured by percent bottom cover, than adjacent areas low macrophyte abundance. Plots abundance versus size showed that vegetated sites had densities fish, smaller and greater species richness unvegetated sites. Using information on biomass (B) (W), a (PI) calculated log10 PI = –0.35 W + 0.90 B. The related to density, phosphorus, slope the area, richness. regression model...

Freshwater ecosystems and the fisheries they support are increasingly threatened by human activities. To aid in their management protection, we outline nine key principles for supporting healthy productive based on best available science, including laws of physics chemistry apply to ecology; population dynamics regulated reproduction, mortality, growth; habitat quantity quality prerequisites fish productivity; connectivity among habitats is essential movements fishes resources; freshwater...

Rushed efforts to repair freshwater ecosystems are obstructing the scientific assessment of successes and failures. Existing ecosystem science is ignored as ecologists plan restoration projects. The problem detecting fish responses habitat alterations reviewed via linked issues: expectations, measures, variability, scale. Habitat directed at single species populations usually affect other components. In community, no population reference point for responses. A set 15 alternate highlights...

Species-specific production rate per unit biomass (P/B, year) ratios were calculated for 79 freshwater fish species of eastern Canada. P/B (per using two methods, which based on allometry with weight-at-maturity and life expectancy, respectively. values obtained by the methods significantly correlated, as expected from history theory, since predictors (longevity, size-at-maturity) themselves correlated. also correlated field observations published sources. The estimation size is recommended...

Commonest lake types of the 15 combinations four fish species (walleye, Stizostedion vitreum vitreum; northern pike, Esox lucius; trout, Salvelinus namaycush and smallmouth bass, Micropterus dolomieui) were walleye–pike (22%), pike "only" (19%), trout (16%) bass (10%). Lake trout–walleye trout–walleye–smallmouth extremely rare. depth area variables greatest significance in distinguishing by discriminant analysis. Climatic factors explained general geographic distribution bass. Hypotheses to...

A large data set on Ontario lakes and their fish species was examined for evidence of the influence richness regional, local, anthropogenic, methodological factors. Analysis regional distributions associations showed patterns consistent with invasion into since last period glaciation. comparison local (mean among lakes) pointed to a dominance over factors in determining lake richness. multiple regression model accounted 48% variance. Of two included model, watershed increased elevation...

The availability of suitable thermal habitat for fishes in streams is influenced by several factors, including flow, channel morphology, riparian vegetation, and land use. This study examined the influence air temperature groundwater discharge, predictors stream temperature, on diversity (cold-, cool-, warm-water preferences) fish communities southern Ontario watersheds. Site-level sampling data were used to assess 43 quaternary watersheds using three metrics, proportion sites within a...

Habitat temperature is a major determinant of performance and activity in fish. We summarize published studies 173 North American freshwater fish species to examine the interrelationships among thermal response metrics associated with three types individual performance: growth (optimal (OGT), final preferendum (FTP)), survival (upper incipient lethal (UILT), critical maximum (CTMax)), reproduction (optimum spawning (OS), optimum egg development (OE)). found that all were highly correlated,...

Changes in resource development and expansions of urban centres suggest that the intensity types anthropogenic stressors affecting Canada’s watersheds are changing. Chu et al. (2003) integrated indices freshwater fish biodiversity, environmental conditions, stress to identify priority for conservation management. Here, we update those using recent climate census data assess changes through time. We also applied different management scenarios evaluate robustness our prioritization approach....

We used acoustic telemetry and acceleration sensors to compare population-specific measures of the metabolic costs an apex fish predator living in four separate lakes. chose our study species populations provide a strong test recent theoretical predictions that optimal foraging by typical aquatic environment would be consistent with feeding satiation rather than continuous feeding. where primary prey type differed along body size gradient (from small invertebrates large planktivorous fish)...

Linked regional chemical and biotic models predicted that at least 20% of all lakes in 15 38 secondary watersheds eastern Canada had lost their potential species richness given 1980 acidic sulphate deposition levels; represents circa 55 000 lakes. Fish molluscs were the most affected seven aquatic taxonomic groups, rotifers least. Mean percent loss ranged from 5.0 to 9.5% for groups biota under deposition. Sulphur dioxide emission reductions 42% United States reduce number seven, leaving 25...

Abstract Presence‐absence data for New Zealand's freshwater fish fauna were analysed evidence of species interactions and links with land‐use geological patterns. Co‐occurrence patterns differed between site regional levels. Native exotic had overlapping geographical distributions but tended to be segregated at the level. Species‐area curves developed lotic lentic sites which explained a small portion variation. Regressions involving variables accounted more Zealand catchments appeared...

Knowledge of Canada’s lakes is needed to manage environmental stresses. Lake inventory and lake feature databases were used build a national impact assessment template assess regional typology. There are ~910 400 with area ≥ 0.1 km 2 (10 ha), 37% the Earth’s total. features (number by size class, maximum depth, mean–maximum depth ratio, Secchi pH, total dissolved solids) modeled regionally secondary watershed (SWS) using linear regression models. trout ( Salvelinus namaycush ) occurrence was...

Climate change and invasive species are two stressors that should have large impacts on native in aquatic terrestrial ecosystems. We quantify integrate the effects of climate establishment an (smallmouth bass Micropterus dolomieu ) lake trout Salvelinus namaycush populations. assembled a dataset almost 22 000 Canadian lakes contained information fish communities, morphologies, geography. examined pelagic‐benthic littoral forage community available to populations across three size classes...

In situ and remote-sensed data on freeze-up break-up dates for lakes spread over much of Canada were used to develop validate simple regression models linking lake ice phenology climatic conditions morphometry. The primary variables affecting fall the date when 30-day smoothed air temperatures reached 0 °C mean depth; spring °C, solar elevation that date, number days winter <0 °C. These project potential impacts climate change across Canada; by 2055 (under Intergovernmental Panel Climate...

Abstract Climate warming is a major disruptor of fish community structure globally. We use large-scale geospatial analyses 447,077 Canadian Arctic lakes to predict how climate change would impact lake thermal habitat diversity across the landscape. Increases in maximum surface temperature (+2.4–6.7 °C), ice-free period (+14–38 days), and stratification presence (+4.2–18.9%) occur under all scenarios. Lakes, currently fishless due deep winter ice, open up; many thermally uniform become...

Conservation, like beauty, is clearly in the eye of beholder. The lack a clear definition what meant by term conservation, however, may encourage misconceptions about degree to which biological objectives can be traded off against pressing economic and social objectives. Our purpose promote dialogue meaning practice might lead toward consensus on essential We present brief history philosophical evolution conservation offer based argument for an ecological ethic. This ethic requires that...

This study presents a broad analysis of freshwater fish species biodiversity in relation to environmental and stress metrics throughout Canada. Species presence–absence data were used calculate richness rarity indices by tertiary watershed. Richness is higher the southern parts Canada, whereas concentrated "ring rarity" around periphery country. Environmental developed for each watershed using readily available mapped information. The index was estimated growing degree-days above 5°C,...