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Understanding detection range is a key factor for the use of acoustic telemetry in fisheries research. Lakes have strong seasonal changes in thermal stratification, as well as short-term changes due to internal seiches. These thermal gradients in lakes imply strong sound-speed gradients that can refract and diverge acoustic signals, leading to acoustic attenuation and smaller detection range. Using field-based range testing and the Bellhop acoustic model, we investigated how changes in stratification lead to changes in detection range within Hamilton Harbour, Ontario, Canada. During the summer stratified period, the detection range was less than 350 m, whereas in the isothermal fall, range was up to 500 m. Range test data from three separate field observations showed a good correlation with Bellhop predictions. Owing to the intense internal seiches in Hamilton Harbour, the stratification in the shallower littoral regions essentially switched between stratified and isothermal conditions over short timescales, which is predicted to lead to high temporal variability in detection range that must be accounted for during the analysis and interpretation of telemetry-derived data.

Two primary goals in fisheries research are to (i) understand how habitat and environmental conditions influence the distribution of fishes across the landscape and (ii) make predictions about how fish communities will respond to environmental and anthropogenic change. In inland, freshwater ecosystems, quantitative approaches traditionally used to accomplish these goals largely ignore the effects of species interactions (competition, predation, mutualism) on shaping community structure, potentially leading to erroneous conclusions regarding habitat associations and unrealistic predictions about species distributions. Using two contrasting case studies, we highlight how joint species distribution models (JSDMs) can address the aforementioned deficiencies by simultaneously quantifying the effects of abiotic habitat variables and species dependencies. In particular, we show that conditional predictions of species occurrence from JSDMs can better predict species presence or absence compared with predictions that ignore species dependencies. JSDMs also allow for the estimation of site-specific probabilities of species co-occurrence, which can be informative for generating hypotheses about species interactions. JSDMs provide a flexible framework that can be used to address a variety of questions in fisheries science and management.

The Canadian Fisheries Research Network (CFRN) was a collaboration among fish harvesters, academic researchers, and government scientists that undertook research between 2010 and 2016 on questions about fisheries that were identified by fish harvesters and pertinent to management objectives. This paper provides a synthesis of the scope and results of the CFRN. It explores the link between the increasing challenges to fisheries sustainability and the need for increased research capacity and for a collaborative approach. It documents the creation of the collaboration, the research it accomplished, and its benefits and explores the need for ongoing collaboration. The papers in this special issue on the CFRN demonstrate the benefits of collaborative fisheries research that are of relevance internationally and support the need for a permanent collaborative platform to conduct research to support fisheries management capacity and decision-making in Canada.

Fisheries involve complex problems not easily addressed by a single discipline, methodology, or set of stakeholders. In 2010, the Canadian Fisheries Research Network (CFRN) was initiated to increase fisheries research capacity in Canada through interdisciplinary and inclusive research collaborations. As post-graduate students in the network, we reflected on the type of training necessary to tackle fisheries problems and reviewed opportunities available at Canadian universities to receive such training. This paper presents an overview of fisheries education currently available in Canada, reflects on our training within the CFRN, and proposes improvements to fisheries education and research. Our review of the subject revealed few dedicated fisheries programs, limited interdisciplinary programs, few specialized fisheries training programs, and a heavy reliance on academic supervisors to secure research opportunities in fisheries. In contrast, the CFRN enhanced our training by deliberately focusing on tools and techniques to address fisheries issues, providing venues to foster interdisciplinary and inclusive research collaborations, and exposing the realities of stakeholder collaborations. We call for post-graduate-level fisheries education and research that is interdisciplinary, collaborative, and inclusive to produce well-rounded scientists and managers, and we suggest ways that universities, researchers, and funding agencies can incorporate these themes into fisheries education and research.

This review assessed the status and scope of freshwater hydroacoustic fisheries research in global aquatic ecosystems with emphasis on (i) geographical and spatial scope, (ii) taxonomic range at the species and family levels (restricted to bony fishes of the Actinopterygii and Sarcopterygii), and (iii) temporal scope. Hydroacoustic measures have been used by ecologists and managers of freshwater systems for several decades, with major progress in technology and methods in recent years. A literature review indicated 296 research contributions that employed hydroacoustics to study freshwater fisheries in 294 different aquatic ecosystems. Spatially, hydroacoustics research in freshwater systems have thus far been concentrated in developed countries, particularly in North America and Northern and Central Europe (83% of the studies reviewed here). Most studies were small in spatial scale and short-term, with 80% including only a single body of water and 63% conducted over a single year or season (75% spanning less than two years). In addition, effects of fish morphology and behavior on acoustic target strength (TS) and taxonomic identification are not well parameterized, with only 21 species receiving empirical study of TS. Despite progress, the present study reveals gaps in the knowledge needed for wider applications to management. These include larger biogeographical and temporal scales of study and further empirical research on TS and taxonomic identification. Recent advances in size rather than species-based methods and theory offer potential solutions to this issue but require further investigation. We conclude with recommendations for systematic hydroacoustic research to enable more effective monitoring, management, and conservation of fisheries and freshwater ecosystems.

Relationships among catch, fishing effort, and measures of fish stock abundance have several implications for fisheries research. In this context, spatial and seasonal aspects are of significant importance for management decisions, especially when effort regulation schemes are used. In this paper, the multispecies trawl fishery in the Northern and Central Adriatic Sea was investigated, taking into account the heterogeneous distribution of fish stocks. Two approaches are presented depending on the availability (or not) of fishery-independent indices of stock abundance. The empirical results indicate that (i) aggregation and targeting behaviours affect catches by modifying the relationship between abundance and catch per unit effort and (ii) these relationships are not homogenous across space. Data from the Adriatic Sea is still insufficient to guarantee reliable estimations. However, these preliminary results call into question management decisions being made on the basis of catch per unit effort. Furthermore, the high heterogeneity between the northern and central areas of the sea basin calls for the adoption of spatially explicit management systems.

Tracking vessel movements has become increasingly important in fisheries research to identify fishing grounds, monitor responses to area closures, and other actions for fishery managers. Vessel monitoring systems (VMS) have given fishery managers and researchers the ability to study vessel interactions by automated tracking of vessels throughout fishing seasons. The high spatial and temporal resolution obtained from VMS records in the Gulf of St. Lawrence snow crab (Chionoecetes opilio) fishery provides information on movement patterns and fishing locations. With the use of hidden Markov models (HMM), we inferred behaviours exhibited by the fishermen during the course of fishing trips and related these behaviours to catch rates across years with varying abundance estimates. The HMM classified three behavioural states in the VMS data that were identified with travelling, setting traps in novel locations (new sets), and retrieving previously set traps (resets). Catches within a trip were modeled by combining VMS-based estimates of these behaviours with logbook information in a generalized linear model. Our model demonstrates that behavioural variables can contribute to the standardization of catch similar to classical trip and vessel variables used in constructing abundance indices.

Nearly 40% of commercial fisheries have now collapsed or are in serious decline. In response, governments have invested millions of dollars into artificial breeding programs, but many programs have failed to rehabilitate dwindling wild stocks. This failure may in part lie in the lack of knowledge about the genetic architecture of fitness: the genes and genotypes that are associated with individual performance. In this paper we discuss (i) artificial breeding programs, (ii) the genetic architecture of fitness, (iii) additive and nonadditive genetic effects on fitness, (iv) genetic diversity and evolvability, and (v) natural breeding and adaptation. We argue that most breeding programs do not maintain genetic adaptations and may consequently be ineffective at rehabilitating or enhancing wild populations. Moreover, there is no evidence that preserving genetic diversity as measured from neutral genetic markers increases fish performance or population viability outside of populations that experience strong inbreeding depression, and limited data that genetic diversity increases the potential for populations to adapt to changing environments. We suggest that artificial breeding programs should be used only as a last resort when populations face imminent extirpation and that such programs must shift the focus from solely preserving genetic diversity to preserving genetic adaptations.

Ecologists are increasingly interested in how disjunct habitats are connected through the cross-habitat movement of matter, prey, nutrients, and detritus and the implications for recipient systems. The study of lake ecosystems has been dominated by the study of pelagic (open-water) production and processes, though there is growing awareness of the role of terrestrial inputs and benthic trophic pathways. Here, we review the phenomena of airborne fluxes to and from lakes. We assemble published data on terrestrial particulate organic carbon (TPOC) deposition to lakes, insect production, and insect emergence and use these data to simulate how airborne lake-to-land and land-to-lake carbon flux is expected to scale with ecosystem size, while taking into account among-lake variability in emergence and TPOC deposition. Emergent insect flux to land increases as a function of lake size, while TPOC deposition to lakes decreases as a function of lake size. TPOC deposition exceeds insect emergence in small lakes, while in large lakes, insect emergence exceeds TPOC deposition. We present a general framework for considering directional fluxes across habitat boundaries. Furthermore, our results highlight the overarching role of ecosystem geometry in determining insect emergence, airborne carbon deposition, and net carbon flux between adjacent ecosystems.

I briefly trace the evolution of the Experimental Lakes Area project from its beginning as a temporary site sponsored by the now-defunct Fisheries Research Board of Canada, with the sole mandate to investigate the effects of nutrients on lake eutrophication, to its current status: a permanent field station cosponsored by the Canadian Departments of Environment and Fisheries and Oceans, with a mandate to investigate the aquatic effects of a wide variety of stresses on lakes and their catchments. Throughout, experiments have been designed to address important aquatic management issues, but this mandate has not hindered the production of pure research on a broad variety of issues.

Ecological speciation occurs when adaptation to different environments or resources causes the evolution of reproductive isolation. This process is now thought to be very important in the evolution of biological diversity. Indeed, support for ecological speciation is so often asserted in the literature that one can get the impression of ubiquity. Eager to ride on the coattails of this exciting work, my own research has investigated ecological speciation in guppies, sticklebacks, and Darwin’s finches. Much to my initial dismay, I failed to find simple and strong signatures of ecological speciation in the first two of these systems. Setting aside the possibility of personal incompetence, my apparent deviation from ubiquity might simply reflect an existing literature bias. This bias seems obvious in retrospect given that essentially all published studies of ecological speciation purport to be confirmatory, whereas many cases of divergent selection and adaptive divergence are associated with only weak to modest levels of reproductive isolation. In short, different populations can be arrayed along a continuum from panmixia to complete reproductive isolation. Variation along this continuum might profitably be used for studying factors, outlined herein, that can promote or constrain “progress” toward ecological speciation.

Estimation of von Bertalanffy growth parameters has received considerable attention in fisheries research. Since Sainsbury (1980, Can. J. Fish. Aquat. Sci. 37: 241–247) much of this research effort has centered on accounting for individual variability in the growth parameters. In this paper we demonstrate that, in analysis of tagging data, Sainsbury's method and its derivatives do not, in general, satisfactorily account for individual variability in growth, leading to inconsistent parameter estimates (the bias does not tend to zero as sample size increases to infinity). The bias arises because these methods do not use appropriate conditional expectations as a basis for estimation. This bias is found to be similar to that of the Fabens method. Such methods would be appropriate only under the assumption that the individual growth parameters that generate the growth increment were independent of the growth parameters that generated the initial length. However, such an assumption would be unrealistic. The results are derived analytically, and illustrated with a simulation study. Until techniques that take full account of the appropriate conditioning have been developed, the effect of individual variability on growth has yet to be fully understood.

Ninety-eight percent of recently surveyed papers in fisheries and aquatic sciences that did not reject some null hypothesis (H0) failed to report β, the probability of making a type II error (not rejecting H0 when it should have been), or statistical power (1 – β). However, 52% of those papers drew conclusions as if H0 were true. A false H0 could have been missed because of a low-power experiment, caused by small sample size or large sampling variability. Costs of type II errors can be large (for example, for cases that fail to detect harmful effects of some industrial effluent or a significant effect of fishing on stock depletion). Past statistical power analyses show that abundance estimation techniques usually have high β and that only large effects are detectable. I review relationships among β, power, detectable effect size, sample size, and sampling variability. I show how statistical power analysis can help interpret past results and improve designs of future experiments, impact assessments, and management regulations. I make recommendations for researchers and decision makers, including routine application of power analysis, more cautious management, and reversal of the burden of proof to put it on industry, not management agencies.

Most fisheries problems arise from a failure to understand and manage fishermen, and that the study of fishermen should be a major part of fisheries research. The dynamic behavior of fishing fleets can be broken into four components: investment, movement, catching power, and discarding. The literature in each area is reviewed and the needed research described. The second part of this paper examines the causes and consequences of individual variation in catch in a commercial purse seine fishery and a recreational hook and line fishery. It is shown that the catch is highly concentrated in the recreational fishery with a small proportion of frequent anglers catching a large portion of the fish. Catch is more equitably distributed in the purse seine fishery. The consequence of individual variation includes the observation that small annual bag limits in the sport fishery could reduce the total catch significantly while leaving most anglers unaffected and the fact that buy back of the most successful vessels would reduce the commercial catch by relatively little.

A common, although generally unrecognized, use of multistage sampling designs in freshwater fisheries research is for estimation of the total number of fish in small streams. Here there are two stages of sampling. At the first stage one selects a sample of stream sections, usually of equal length, and at the second stage one estimates the total number of fish present in each selected section. This paper argues that the conventional practice of selecting stream sections of equal length is ill-advised on both biological and statistical grounds, and that errors of estimation of fish numbers within selected sections will usually be small compared with errors of estimation resulting from expansion of sampled sections to an entire stream. If stream sections are instead allowed to vary in size according to natural habitat units, then alternative two-stage sampling designs may take advantage of the probable strong correlation between habitat unit sizes and fish numbers. When stream sections of unequal sizes are selected with probabilities proportional to their size (PPS), or measures of the sizes of selected sections are incorporated into estimators, one may substantially increase precision of estimation of the total number of fish in small streams. Relative performances of four alternative two-stage designs are contrasted in terms of precision, relative cost, and overall cost-effectiveness. Choice among alternative designs depends primarily on the correlation between fish numbers and habitat unit sizes, on the total number of stream sections, and on sample size. Recommendations for choices among the designs are presented based on these criteria.

The idea of having government research supervised by a group of knowledgeable individuals outside of the government service began, in Canada, in the field of aquatic science and fisheries. In 1898 an honorary Board of Management was set up to establish and manage a biological station on the Atlantic coast. As this Board’s responsibilities increased it was renamed the Biological Board of Canada, and finally the Fisheries Research Board of Canada. Starting in 1973 the Board ceased to have direct responsibility for the management of research stations, but it continues as an advisory body.During the period 1898–1972 the Board has provided facilities for original research on aquatic animals and plants and on the waters they inhabit, much of it done by scientists from universities and museums; it has solved many problems faced by governments in locating, evaluating, managing and increasing fish stocks; and it has assisted the fishing industry with improved techniques for catching, handling, processing and marketing its products. The immediately useful results of the Board’s work have been made available to the Canadian community through reports, publicity and personal contacts. Details of scientific discoveries have been published in the Board’s Journal and other outlets, while results of research done in other countries have been sifted and interpreted for their application to the Canadian scene.

The von Bertalanffy growth curve is often used in fisheries research to describe the relationship between the weight or length of a fish and its age. The equation is also encountered in various other branches of science and applied science in a variety of different parameterizations and names; for example, it is also known as the asymptotic regression equation or the three-parameter exponential equation. Since these equations are all nonlinear regression models, the properties of the least squares estimators of the parameters of these models may be very different from their large-sample properties, where the estimators are unbiased, have the minimum attainable variance, and are normally distributed, the conditions that pertain in a linear model. Different parameterizations will have estimators which approximate the asymptotic properties to varying degrees of closeness. My study of eight parameterizations shows that one of them, a generalization which allows unequal age increments of a parameterization proposed by Schnute and Fournier, is far superior to any of the other models, which include the most commonly used parameterization, in that it exhibits close-to-linear behavior. Two of the three parameters in this model represent the expected mean lengths corresponding to the youngest and oldest ages, respectively, in the sample, and thus have a ready biological interpretation. I discuss why it is important to have a close-to-linear model when one wishes to make comparisons between two or more data sets. Methodology is briefly described for carrying out such comparisons, and some further remarks are made about why biologists should be concerned about the statistical properties of the models that they use. Although most data sets I used for illustration are obtained from marine animals, the conclusions are general and apply to all disciplines which make use of the von Bertalanffy model in whichever guise or form it appears.

This report was prepared as background material for the Fisheries Research Board of Canada study on oceanography in Canada. Models of the large-scale or general circulation of the ocean are examined first. The general approach to such modeling and a series of models are described and the status of modeling is discussed. It appears that such models are another useful way to study the ocean. However, the resolution of present models is not sufficient to include all possibly important dynamic effects. Developments in computational techniques and computers suggest that these problems can be overcome. Besides the resolution problem, the lack of sufficient data, particularly of currents, makes it difficult to tell how well the models reproduce reality. Data collection programs, designed to use observational knowledge and results of analytical and numerical modeling, will be required for input and verification of numerical models. The use of models should reduce the effort to where it is practicable though difficult and likely to tax the oceanographic community’s resources to the limit. Modeling of coastal regions, semienclosed seas, and estuaries is described and some models of the ocean mixed layer are presented. The upper-layer models are required to provide better bottom boundary conditions for numerical atmospheric models to predict weather and climate in addition to the oceanographic results they produce.An assessment of the usefulness of numerical models for prediction is attempted. Models of rivers and coastal models of tidal amplitudes and currents appear to be quite useful. Models of other regions are not developed and verified well enough to use for prediction but by analogy with river and coastal models and atmospheric models there appears to be a good possibility for useful predictions in future. Finally, suggestions are made for further development of the Canadian program of numerical modeling. Clearly there is a need for the results of coastal and estuarine models, so present programs require some expansion. To get the desired results much faster computers are essential. Acquisition of such computers will make possible the development of a program of modeling the large-scale circulation which will be needed to provide boundary conditions for the coastal models, and could provide an important contribution to the world effort in modeling the general circulation of the ocean.

The evolution of the Biological Stations established by the Government of Canada at St. Andrews, N.B., and Nanaimo, B.C., in the summer of 1908 is outlined from small operations with limited facilities ashore and afloat manned seasonally by volunteer university scientists to modern well-equipped laboratories used by year-round scientific and technical staffs. The excellence of the work of the two stations depended on the independence and scientific integrity of the Biological Board (1912–37) and the Fisheries Research Board (1937–73) with memberships combining representatives of government and industry with a majority of university scientists. Under the Board the stations maintained a high level of efficiency and a good balance between short-and long-term and between fundamental and applied research. Programs were responsive to the needs of government and industry and made important contributions to fisheries management and development both domestic and international in both the Atlantic and the Pacific. It is hoped that the new regime may be modified to enable the stations to continue the level of excellence achieved under the Board.

Past and current research by the Fisheries Research Board of Canada related to olfactory and visual responses in Pacific salmon is reviewed, including comments on some of the sensory and behavioural relations important in migration.An innate ability to perceive highly dilute odours supports the view that olfaction can be instrumental in detecting a distant source, but the problems of following a well directed course indicate likely support from other sensory paths including visual and acoustico–lateralis responses.A threshold visual sensitivity of about 1/300 that of bright moonlight and an ability to orient at night, with view of the sky only, provide evidence that retinal images may be useful as migratory cues as long as turbidity does not interfere.

The plankton material collected by the 1923 expedition of the Canadian Fisheries Research Board was examined with regard to appendicularians (Tunicata). Their occurrence supports the thesis that these animals can serve as current indicators, as suggested by previous authors for the same waters. The distribution of the water of the Labrador current around Newfoundland is traced by the occurrence of oikopleurids, and of their separate age classes, in the hauls. The results agree with the hydrographic data of the expedition and with the distribution of other planktonic groups. Partial disintegration of live appendicularians in response to unfavourable environmental conditions was common, especially where waters of different character mix.

Observations were made of salinity, temperature, and dissolved oxygen in 15 inlets in southeast Alaska in June 1964 and August 1965 with some observations in the southern inlets in May 1966. The data are summarized in tables, vertical profiles, and characteristic diagrams to provide a general description of the water property distributions in the larger inlets. Some comparisons are made with corresponding distributions in British Columbia inlets, previously described by Pickard in June 1961 in the Journal of the Fisheries Research Board of Canada.The larger Alaska inlets are longer and wider than those in British Columbia but the mean and maximum depths are similar. Sill depths are also similar and there are few very shallow sills. The river runoff into the Alaska inlets is generally less than into the British Columbia ones. The larger rivers (the minority) have a summer maximum from glacier and snowfield melt whereas the smaller ones generally have fall and winter maxima. Icebergs occur in some of the Alaska inlets; they are not found in any British Columbia inlets.Surface salinities were generally higher in Alaska than in British Columbia, and at the heads of the inlets the highest salinity values were in the "iceberg" inlets. Surface temperatures were between 5 C (in the iceberg inlets) and 18 C. Salinity increased with depth, reaching 90% of the deep water values by 20 m or less. The deepwater characteristics extended the British Columbia inlet values toward higher salinity (to 34‰) and lower temperature (to 2.5 C in the north). Dissolved oxygen decreased with depth in most cases with the lowest values of 1.5–2 ml/liter in the deep water where there was direct access for northeast Pacific Ocean waters. A conspicuous exception was that the deepwater oxygen values were high in the iceberg inlets (5–6.5 ml/liter). Secchi disc depths varied from 0.1 m near the large rivers to 11 m near the Pacific Ocean.There were some differences between the property distributions observed in 1964 and in 1965. Salinity and temperature differences in the surface layers are presumed to be due to seasonal variation in river runoff and net heat input. Lower temperatures in the deep water of some of the northern inlets in 1965 compared to 1964 may be due to larger than usual winter cooling between the years.

A coldroom complex recently installed at the Fisheries Research Board of Canada, Freshwater Institute laboratory at Winnipeg features several design aspects that are considered novel. These include foamed-in-place urethane insulation, two alternating R-502 refrigeration systems incorporating automatic safety switch-over and adjustable defrost, "straight-line" pneumatic temperature control, hot gas bypass control, and a master panel. The facility combines a cold laboratory at +2 C, a long-term storage room at −37 C, a small anteroom at −26 C, and a room containing eight 10.0-ft3 precise temperature cabinets at −40 C. Room temperature variation is ±0.25 degrees C during steady state conditions. Temperature rise during daily defrosting is less than 2 degrees C for a duration of 1 hr.

A discussion of the composition and distribution of plankton organisms forms a basis for the presentation of a critical review of methods of plankton collection. The quantitative sampling of plankton by pumps, water samplers, tow nets, plankton traps and the Clarke-Bumpus sampler is discussed. Data of a comparative nature dealing with some of the more usual methods are presented. A new instrument, the Toronto Sampler, developed at the Ontario Fisheries Research Laboratory, is described and its performance is assessed.

Observations of temperature, salinity and dissolved oxygen content in all but one of the inlets of ten or more miles in length along the west coast of Vancouver Island were made by the University of British Columbia in 1959 and some additional observations were made in 1960 and 1961. The data are summarized to provide a general picture of the oceanographic characteristics of fifteen inlets. Attention is drawn to various features, and comparisons are made with the previous data which are available for only five of the inlets here described. Comparisons are also made with inlets in the mainland coast of British Columbia previously described by Pickard in 1961 in the Journal of the Fisheries Research Board of Canada.Generally the Vancouver Island inlets are shorter and shallower than those of the mainland coast and have shallower sills. The river runoff into the inlets is considerably less than into the mainland ones and has a winter maximum in contrast to the summer maximum on the mainland.Surface salinities during the summer in 1959, 1960 and 1961 were in most cases between 12 and 28‰ at the inlet head increasing to 27–31‰ at the mouth, while surface temperatures were between 10 and 15 °C. The low-salinity surface layer had a thickness of 2 m or less in all but two cases. Secchi disc depths were usually from 4 to 8 m. The deep water characteristics were from 7.5 to 9.5 °C and 31 to 33.6‰ except in the Clayoquot Sound group where the water was warmer (to 15.4 °C) and less saline (to 24.8‰). Dissolved oxygen values were very variable even along individual inlets. At depths greater than 100 m the content was usually less than 4 ml/l and in many cases less than 1 ml/l. The effect of the shallow sills in limiting deep water circulation appeared to be significant.Even when all the available data are assembled there are no time series of observations sufficient to prepare a description of seasonal variations of water properties, but data for six years from 1939 to 1961 are available for Alberni Inlet and for three years for the Nootka Sound inlets and for Neroutsos Inlet. These data indicate that in the deep water changes of up to 0.4‰ in salinity, 1 °C in temperature and 2.5 ml/l in dissolved oxygen content may occur from year to year.An hypothesis is advanced that, on account of the relatively shallow sills of many of the inlets, the deep water in their basins forms a 'memory' of extreme (high density) conditions of the continental shelf waters outside the inlets, and that the consistency of the basin water characteristics in the inlets suggests that the water properties observed in the shelf waters in 1959–61 by the Pacific Oceanographic Group may be typical of shelf waters in this region over many years.

Recently, a series of computer programs was developed by the Fisheries Research Board of Canada Pacific Oceanographic Group to enable more intensive studies to be carried out of the effects of winds over the ocean surface on the circulation in the ocean. The programs are used to compute geostrophic velocities and mass transports from oceanographic station data, Ekman and total transports from mean sea-level atmospheric pressure.The theoretical background for the programs is developed and examples of the results obtained are given. More complete discussions of the results will be given as processed information is accumulated.

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Material for this study was gathered by field parties of the Fisheries Research Board in the summers of 1944, 1945 and 1946. A description of the subspecies is given, based on measurements of 26 specimens. The distribution of Stenodus in Great Slave Lake, and in northern North America is outlined. The rate of growth was determined from an examination of scale samples from 298 fish, and it was found that the inconnu has a rapid growth rate, even in this highly oligotrophic lake. Inconnu spawn mainly in the rivers which enter Great Slave Lake from the Mackenzie Lowlands. The upstream run apparently occupies most of the summer but evidence is presented which indicates a major movement in late August. The post-spawning, downstream run takes place in late September or early October. Residents take advantage of it to put up inconnu for winter dog feed. The food of young inconnu in the spawning streams was found to be mainly invertebrates, whereas in Great Slave Lake the species is almost entirely piscivorous. A list of parasites is given, among which Triaenophorus crassus is considered of major importance. The rate of infestation with the larvae of this worm is high—88 per cent of 49 fish examined, at a rate of 64 cysts per 100 pounds. At present the major use of the inconnu is in the domestic fishery where it serves local trappers, and others, as dog feed.

The ascidians of the Canadian Arctic collected by the Eastern Arctic Investigations and Arctic Unit of the Fisheries Research Board of Canada from the years 1947 to 1962 inclusive have been identified and the numbers collected tabulated. Information relevant to collecting stations is presented in tables and on maps.

The first systematic study of physical oceanographic characteristics of the fjord inlets of Chile was carried out by the Institute of Oceanography of the University of British Columbia during March 1970 as Phase V of the Hudson 70 Round-the-Americas Expedition of the Bedford Institute, Canada Department of Energy, Mines and Resources.Observations were made of temperature, salinity, and dissolved oxygen at 175 stations in 32 inlets and in the passages outside them, and soundings were made along 3500 km of track. The sounding data are presented as longitudinal sections, and water properties are summarized in temperature–salinity and temperature–dissolved oxygen correlation plots and characteristic diagrams; comparisons are made with observations for the British Columbia and Alaska inlets reported by Pickard in 1961 (18: 907–999) and 1967 (24: 1475–1506) in the Journal of the Fisheries Research Board of Canada. Observations were also made of nutrients in some Chilean inlets; these will be reported at a later date.In mean and extreme values, the dimensions of the inlets in Chile are similar to those in British Columbia/Alaska; only two shallow sills were recorded. More inlets had glaciers contributing melt water directly to them and more had icebergs present than is the case in the northeast Pacific inlets. Vertical salinity profiles in Chile were similar to those in British Columbia/Alaska, but the thinner surface layer was of higher salinity, except in the inlets having icebergs, and the deepwater salinities were 1–2‰ higher in Chile. Temperatures were 2–5 degrees C higher in Chile except in the iceberg inlets where surface values were lower than those in Alaska. Several of the iceberg inlets in Chile had much more complicated temperature/depth profiles than in Alaska, with as many as seven maxima and minima below the surface. The glacial silt in the inlet waters was more conspicuous and extensive in Chile than in British Columbia/Alaska. Dissolved oxygen values in Chile were much the same as in British Columbia/Alaska with higher values in the iceberg inlets in Chile than in Alaska, and there was little evidence of very low values characteristic of stagnant basins. The lack of low dissolved oxygen values suggests free exchange with outside waters and the inlet deepwater characteristics indicate that the effective sill depths between inlets and the ocean are only 100–150 m deep. At least four distinct major regions are evident from water properties among the inlets of Chile.

Most of the young fish of nine species that were entrained in the condenser cooling-water system of the Connecticut Yankee nuclear power plant were dead by the time they reached the lower end of the plant’s 1.83-km (1.14 mile) long discharge canal. Sampling during June and July, when 95% of the nonscreenable fish were abundant near the plant’s intake, showed that approximately 80% of the mortality in the canal was caused by mechanical damage and 20% was attributed to heat shock and prolonged exposure to temperatures elevated above 28 C. There was no measurable mortality due to the injection of sodium hypochlorite into the system as a biocide. The number of nonscreenable living fish entrained at the intake averaged about 4% (range, 1.7–5.8%) of those passing by the plant under conditions of unidirectional net tidal flow.

A list is given of 180 stations where marine biological, oceanographic and fishing observations or collections were made by the Calanus and land-based investigations of the Arctic Unit between Labrador and the Yukon–Alaska boundary from 1955 to 1958.

In August 1967, a specimen of the Bering poacher, Occella dodacaedron (Tilesius), was taken by a commercial fisherman in Chignik Bay, Alaska; this catch indicates that it ranges farther south than Bristol Bay, the previously reported limit of its distribution. Sampling by beach seine by personnel of the Fisheries Research Institute in Chignik Lagoon, Alaska, in 1963–65 and in 1967, showed that the staghorn sculpin (Leptocottus armatus Girard) was a common resident; the northwestern range of the species is clarified.

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