Consideration of ocean conditions in the management of salmon

1998 ◽  
Vol 55 (9) ◽  
pp. 2178-2186 ◽  
Author(s):  
Gustavo A Bisbal ◽  
Willis E McConnaha
Keyword(s):  
Environmental Variability ◽  
Holistic Approach ◽  
Anthropogenic Factors ◽  
Freshwater Environment ◽  
Conceptual Foundation ◽  
Variable Environment ◽  
Management Actions ◽  
Salmon Management ◽  
Ocean Conditions ◽  
Ocean Environment

An ecologically based conceptual foundation is presented as a way to incorporate environmental variability in salmon management. The argument addresses the problem of accommodating marine environment variability through actions in freshwater. We argue for an approach that considers marine and freshwater environments as integral components of a larger salmonid ecosystem. This contrasts with previous propositions that either relied heavily on technological fixes in the freshwater environment or questioned the value of any recovery effort designed to withstand overwhelming ocean forces. Salmon management requires a more holistic approach incorporating modern understanding of the salmonid ecosystem and its variability. We suggest two strategies. The first calls for deliberate improvement of estuarine and nearshore ocean conditions through regulation of upstream flows, river operations, hatchery production, and other actions. The second calls for improving the resilience of salmon to a variable environment. This requires relaxing anthropogenic factors that hinder the natural range of salmon life history diversity within and between populations, a survival mechanism that evolved in response to changing conditions. These strategies recognize that although the ocean primarily determines overall salmon abundance, management actions, particularly in freshwater, are critical to the ability of salmon to cope with a variable ocean environment.

Urbanization and stream ecosystems: the role of flow hydraulics towards an improved understanding in addressing urban stream degradation

2021 ◽  
Author(s):  
Desmond Ofosu Anim ◽  
Patrick Banahene
Keyword(s):  
Stream Restoration ◽  
Holistic Approach ◽  
Ecosystem Processes ◽  
Urban Stream ◽  
Management Actions ◽  
Stream Management ◽  
Management Measures ◽  
Hydraulic Conditions ◽  
Primary Driver ◽  
Ecological Objectives

Catchment urbanization is widely recognised as a primary driver of stream degradation by increasing stormwater runoff causing major changes to key ecosystem processes. Reinstating the ‘natural’ hydrogeomorphic conditions is central in designing successful, self-sustaining restoration actions. However, addressing urban stream degradation by re-establishing the hydrogeomorphic conditions remains a challenge and comparatively limited measurable progress has been observed particularly achieving ecological objectives. This paper articulates that stream restoration goals might be better achieved when management measures take a broader approach that considers anticipated hydraulic conditions effects that liaise relationships between flow and ecology. The study argues that fluvial systems are characterised by complex and dynamic ecosystem processes primarily governed by the hydraulic conditions (e.g. velocity, depth, shear stress), thus, as the practice of addressing urban stream restoration becomes increasingly common, it is critical to explore and understand the anticipated response of the hydraulic conditions. This paper describes how hydraulic regime consideration provides further opportunity for a holistic approach to urban stream management given their capacity to account for multiple ecological and geomorphic objectives. The paper suggests that developing suitable flow-biota-ecosystem processes nexus is critical towards addressing urban stream degradation and hydraulic consideration in restoration actions provide an important step towards that. The paper discusses opportunities to evolve management actions to achieve restoration goals by highlighting how the management of the two key levers (addressing altered flow regime and morphology) to improve the hydraulic conditions can help to address the urban stream disturbance.

scholarly journals Timing in a fluctuating environment: environmental variability and asymmetric fitness curves can lead to adaptively mismatched avian reproduction

2012 ◽  
Vol 279 (1741) ◽  
pp. 3161-3169 ◽  
Author(s):  
Marjolein E. Lof ◽  
Thomas E. Reed ◽  
John M. McNamara ◽  
Marcel E. Visser
Keyword(s):  
Temporal Variation ◽  
Environmental Variability ◽  
Environmental Variation ◽  
Reaction Norm ◽  
Optimal Timing ◽  
Variable Environment ◽  
Avian Reproduction ◽  
Breeding Date ◽  
Fitness Curve ◽  
Warming World

Adaptation in dynamic environments depends on the grain, magnitude and predictability of ecological fluctuations experienced within and across generations. Phenotypic plasticity is a well-studied mechanism in this regard, yet the potentially complex effects of stochastic environmental variation on optimal mean trait values are often overlooked. Using an optimality model inspired by timing of reproduction in great tits, we show that temporal variation affects not only optimal reaction norm slope, but also elevation. With increased environmental variation and an asymmetric relationship between fitness and breeding date, optimal timing shifts away from the side of the fitness curve with the steepest decline. In a relatively constant environment, the timing of the birds is matched with the seasonal food peak, but they become adaptively mismatched in environments with temporal variation in temperature whenever the fitness curve is asymmetric. Various processes affecting the survival of offspring and parents influence this asymmetry, which collectively determine the ‘safest’ strategy, i.e. whether females should breed before, on, or after the food peak in a variable environment. As climate change might affect the (co)variance of environmental variables as well as their averages, risk aversion may influence how species should shift their seasonal timing in a warming world.

scholarly journals Coastline evolution of Portuguese low-lying sandy coast in the last 50 years: an integrated approach

2016 ◽  
Author(s):  
Cristina Ponte Lira ◽  
Ana Nobre Silva ◽  
Rui Taborda ◽  
Cesar Freire de Andrade
Keyword(s):  
Coastal Management ◽  
Holistic Approach ◽  
Integrated Approach ◽  
Beach Erosion ◽  
Science Data ◽  
Coastal System ◽  
Dune Systems ◽  
Management Actions ◽  
Coastline Evolution

Abstract. Regional/global-scale information on coastline rates of change and trends is extremely valuable, but national-scale studies are scarce. A widely accepted standardized methodology for analysing long-term coastline change has been difficult to achieve, but is essential to conduct an integrated and holistic approach to coastline evolution and hence support coastal management actions. Additionally, databases providing knowledge on coastline evolution are of key importance to support both coastal management experts and users. The main objective of this work is to present the first systematic, global and consistent long-term coastline evolution data of Portuguese mainland low-lying sandy. The methodology used quantifies coastline evolution using an unique and robust coastline indicator (the foredune toe), which is independent of short-term changes. The dataset presented comprises: 1) two polyline sets, mapping the 1958 and 2010 sandy beach-dune systems coastline, both optimized for working at 1:50 000 scale or smaller, and 2) one polyline set representing long-term change rates between 1958 and 2010, estimated at each 250 m. The science data produced here are in Open Access at doi:10.1594/PANGAEA.853654 and can be used in other studies. Results show beach erosion as the dominant trend, with a mean change rate of −0.24 ± 0.01 m/year for all mainland Portuguese beach-dune systems. Although erosion is dominant, this evolution is variable in signal and magnitude in different coastal sediment cell and also within each cell. The most relevant beach erosion issues were found in the coastal stretches of Espinho – Torreira and Costa Nova – Praia da Mira, both at sub-cell 1b; Cova Gala – Leirosa, at sub-cell 1c and Cova do Vapor – Costa da Caparica, at cell 4. Cells 1 and 4 exhibit a history of major human interventions interfering with the coastal system, many of which originated and maintained a sediment deficit. In contrast, cells 5 and 6 have been less intervened and show stable or moderate accretion behaviour.

scholarly journals Additive effects of climate and fisheries drive ongoing declines in multiple albatross species

2017 ◽  
Vol 114 (50) ◽  
pp. E10829-E10837 ◽  
Author(s):  
Deborah Pardo ◽  
Jaume Forcada ◽  
Andrew G. Wood ◽  
Geoff N. Tuck ◽  
Louise Ireland ◽  
...  
Keyword(s):  
Mitigation Measures ◽  
Adult Survival ◽  
Anthropogenic Factors ◽  
Population Declines ◽  
Management Actions ◽  
Recovery Potential ◽  
Top Predators ◽  
Animal Populations ◽  
Multievent Models ◽  
Anthropogenic Drivers

Environmental and anthropogenic factors often drive population declines in top predators, but how their influences may combine remains unclear. Albatrosses are particularly threatened. They breed in fast-changing environments, and their extensive foraging ranges expose them to incidental mortality (bycatch) in multiple fisheries. The albatross community at South Georgia includes globally important populations of three species that have declined by 40–60% over the last 35 years. We used three steps to deeply understand the drivers of such dramatic changes: (i) describe fundamental demographic rates using multievent models, (ii) determine demographic drivers of population growth using matrix models, and (iii) identify environmental and anthropogenic drivers using ANOVAs. Each species was affected by different processes and threats in their foraging areas during the breeding and nonbreeding seasons. There was evidence for two kinds of combined environmental and anthropogenic effects. The first was sequential; in wandering and black-browed albatrosses, high levels of bycatch have reduced juvenile and adult survival, then increased temperature, reduced sea-ice cover, and stronger winds are affecting the population recovery potential. The second was additive; in gray-headed albatrosses, not only did bycatch impact adult survival but also this impact was exacerbated by lower food availability in years following El Niño events. This emphasizes the need for much improved implementation of mitigation measures in fisheries and better enforcement of compliance. We hope our results not only help focus future management actions for these populations but also demonstrate the power of the modelling approach for assessing impacts of environmental and anthropogenic drivers in wild animal populations.

scholarly journals ALGORITHMS FOR EVALUATING THE EFFICIENCY OF THE BUSINESS PROCESSES OF ENTERPRISE BASED ON A BALANCE SCORE CARD

2021 ◽  
Vol 2 (336) ◽  
pp. 66-73
Author(s):  
S. Israilova ◽  
A. Mukhanova ◽  
A. Satybaldiyeva
Keyword(s):  
Balanced Scorecard ◽  
Business Strategy ◽  
Business Processes ◽  
Weighted Average ◽  
Holistic Approach ◽  
The Balanced Scorecard ◽  
Management Actions ◽  
Score Card ◽  
Efficiency And Effectiveness ◽  
Effective System

The article presents an algorithm for analyzing and evaluating the effectiveness of business processes of enterprises. Modern enterprises must have a well-thought-out and effective system of managing their activities for sustainable competitiveness, which can be achieved on the basis of certain methodological approaches. The profit that is the purpose of the functioning of Kazakhstan enterprises in many cases cannot be obtained, due to the incorrect operation of business processes and the allocation of appropriate resources. Constant modernization of enterprises is a financially costly solution to the problem of ensuring planned income. At the same time, the modernization of the enterprise should be carried out only after a deep analysis and assessment of the "bottlenecks" of the company's business processes. The purpose of the study is to determine the methodology for analyzing and evaluating the business processes of Kazakhstani enterprises in the field of service provision. The proposed methodology is designed to identify "problem" areas of specific business processes by calculating weighted average, integral and generalized indicators of efficiency and effectiveness. This allows you to assess the state of both individual business processes of enterprises and their totality, as well as to set priorities for management actions to improve them. While previous research has attempted to use tools and models to visualize technological business planning, limited previous research has focused on strategic planning modeling. Due to the problems associated with the lack of guidelines for business strategy modeling, a holistic approach is needed. Using the balanced scorecard evaluated the efficiency and effectiveness of business processes on criteria and indicators allow you to monitor current activity and to evaluate the effectiveness of its operations at any time.

scholarly journals Variable Environments in an Upwelling System Trigger Differential Thermal Sensitivity in a Low Intertidal Chiton

2021 ◽  
Vol 9 ◽  
Author(s):  
Nahomi Manríquez ◽  
Leonardo D. Bacigalupe ◽  
Marco A. Lardies
Keyword(s):  
Environmental Conditions ◽  
Environmental Variability ◽  
Adjacent Area ◽  
Abiotic Factor ◽  
Optimal Temperature ◽  
Critical Limit ◽  
Maximum Performance ◽  
Variable Environment ◽  
Physiological Performance ◽  
Variable Environments

Environmental variability in coastal oceans associated with upwelling dynamics probably is one of the most pervasive forces affecting the physiological performance of marine life. As the environmental temperature is the abiotic factor with major incidence in the physiology and ecology of marine ectotherms, the abrupt temperature changes in upwelling systems could generate important variations in these organisms’ functional processes. The relationship between ambient temperature and physiological performance can be described through a thermal performance curve (TPC). The parameters of this curve usually show geographic variation usually is in accordance with the predictions of the climate variability hypothesis (CVH), which states that organisms inhabiting more variable environments should have broader ranges of environmental tolerance in order to cope with the fluctuating environmental conditions they experience. Here we study the effect generated by the environmental variability in an active upwelling zone on the physiological performance of the marine ectotherm Achanthopleura echinata. In particular, we compared the parameters of the TPC and the metabolic rate of two populations of A. echinata, one found in high semi-permanent upwelling (Talcaruca), while the other is situated in an adjacent area with seasonal upwelling (Los Molles) and therefore more stable environmental conditions. Our results show that: (1) oxygen consumption increases with body size and this effect is more significant in individuals from the Talcaruca population, (2) optimal temperature, thermal breadth, upper critical limit and maximum performance were higher in the population located in the area of high environmental heterogeneity and (3) individuals from Talcaruca showed greater variance in optimal temperature, thermal breadth, upper critical limit but not in maximum performance. Although it is clear that a variable environment affects the thermal physiology of organisms, expanding their tolerance ranges and generating energy costs in the performance of individuals, it is relevant to note that upwelling systems are multifactorial phenomena where the rise of water masses modifies not only temperature, but also decreases O2, pH, and increases pCO2 which in turn could modify metabolism and TPC.

scholarly journals Assessment of possible uncertainties arising during the hydromorphological monitoring of a Sand-Bedded Large River

2017 ◽  
Vol 10 (3-4) ◽  
pp. 27-33
Author(s):  
Tamás Právetz ◽  
György Sipos ◽  
Zsuzsanna Ladányi
Keyword(s):  
Morphological Changes ◽  
Time Lag ◽  
Large River ◽  
Bedload Transport ◽  
Repeated Measurements ◽  
Anthropogenic Factors ◽  
Variable Environment ◽  
Digital Elevation ◽  
Adcp Measurements ◽  
Elevation Model

Abstract The riverbed morphology of sand-bedded rivers is dynamically changing as a consequence of quasi continuous bedload transport. In the meantime, the dimension, size and dynamics of developing bedforms is highly depending on the regime of the river and sediment availability, both affected by natural and anthropogenic factors. Consequently, the assessment of morphological changes as well as the monitoring of riverbed balance is challenging in such a variable environment. In relation with a general research on the longer term sediment regime of River Maros, a fairly large alluvial river in the Carpathian Basin, the primary aim of the present investigation was to assess uncertainties related to morphological monitoring, i.e. testing the reproducibility of hydromorphological surveys and digital elevation model generation by performing repeated measurements among low water conditions on selected representative sites. Surveys were conducted with the combination of an ADCP sonar, GPS and total station. The most appropriate way of digital elevation modelling (DEM) was tested and 30-point Kriging was identified to be optimal for comparative analysis. Based on the results, several uncertainties may affect the reproducibility of measurements and the volumetric deviation of DEM pairs generated. The mean horizontal difference of survey tracks was 3-4 m in case of each site, however this could not explain all the DEM deviation. Significant riverbed change between measurements could also be excluded as the main factor. Finally, it was found that results might be affected greatly by systematic errors arising during motor boat ADCP measurements. Nevertheless, the observed, normalised and aggregated DEM uncertainty (600-360 m3/rkm) is significantly lower than the changes experienced between surveys with a month or longer time lag. Consequently, the developed measurement strategy is adequate to monitor long term morphological and sediment balance change on sand bedded large river.

scholarly journals Transdisciplinary approach to solving conservation challenges: A case of Budongo Conservation Field Station, Uganda

2016 ◽  
Author(s):  
Caroline Asiimwe ◽  
Geoffrey Muhanguzi ◽  
Eric Okwir ◽  
Paul Okimat ◽  
Andrew W Bugenyi ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Holistic Approach ◽  
Mitigation Measures ◽  
Anthropogenic Factors ◽  
Human Populations ◽  
Gastrointestinal Infections ◽  
Severe Injuries ◽  
Transdisciplinary Approach ◽  
Field Station ◽  
Budongo Forest

The conservation of chimpanzees (Pan troglodytes) faces complex and dynamic threats, deriving mostly from anthropogenic factors such as high density and poverty in local human populations. One specific threat is poaching, which contributes to both permanent physical disabilities in chimpanzees and cross-species disease transmission. In the Sonso chimpanzee community, Budongo forest, Uganda, over 20% chimpanzees are permanently disabled by indiscriminate poachers’ snare-trap. While severe injuries can sometimes result in death, little is known about the long-term health impacts of poaching to chimpanzees or possible effective mitigation measures. To combat and monitor the complexities of conservation threats, a holistic transdisciplinary approach is required and as a result, the Budongo Conservation Field Station (BCFS) has implemented a comprehensive strategy. Instead of focusing solely on chimpanzee health, our multi-faced tit-for-tat approach also incorporates education and action measures for local communities living adjacent to the forest. To reduce poaching, we provide alternative livelihood sources, veterinary services and education while concurrently employing their local indigenous knowledge of poaching practices to more effectively locate snares/traps in the forest. To mitigate disease transmission across species, beneficiaries in incentive programs must have functional sanitation facilities. To consistently monitor threats and conservation impacts, we routinely collect data on snare recovery and infectious disease prevalence in chimpanzees, humans and livestock. Our preliminary results, since the programs’ inception, show a reduction in respiratory and gastrointestinal infections coupled with an increase in snare recovery from the forest. These findings suggest that our holistic approach is effective in mitigating the threats to chimpanzees in Budongo forest.

Colonization, Adaptation, Radiation, and Diversity in Fresh Water

2020 ◽  
pp. 303-330
Author(s):  
Shane T. Ahyong ◽  
Chao Huang
Keyword(s):  
Fresh Water ◽  
Surface Waters ◽  
Reproductive Strategies ◽  
Environmental Variability ◽  
Inland Waters ◽  
Geological History ◽  
Common Theme ◽  
Freshwater Environment ◽  
Middle Cambrian ◽  
Early Ordovician

About 12,000 of the 67,000 described species of crustaceans occur in fresh water. Crustaceans have colonized almost every type of freshwater environment in most parts of all continents. A common theme in marine-to-freshwater transitions is not only acquisition of osmoregulatory capabilities to cope with hyposalinity, but also optimizing reproductive strategies to cope with ecological and environmental variability. A key reproductive adaptation for fresh water is direct rather than extended planktonic development. Some groups, such as peracarids, were preadapted, already having direct development, whereas others, such as decapods, had to acquire it. Other crustaceans, such as branchiopods, are adapted not only to hyposalinity (and hypersalinity) but also to surviving in transient waters. Crustaceans have been colonizing fresh waters since the Middle Cambrian to Early Ordovician and have independently adapted to life in inland waters many times throughout geological history. The pattern and timing of invasions has shaped present-day distributions. Contemporary distributions and diversity of crustaceans in surface waters are surveyed in the context of their paleohistory. Different groups of crustaceans have very different current distributions that reflect the differential influence of different patterns of colonization, geological history, ecology, and the constraints (or benefits) of their evolutionary heritage.

scholarly journals Changing central Pacific El Niños reduce stability of North American salmon survival rates

2015 ◽  
Vol 112 (35) ◽  
pp. 10962-10966 ◽  
Author(s):  
D. Patrick Kilduff ◽  
Emanuele Di Lorenzo ◽  
Louis W. Botsford ◽  
Steven L. H. Teo
Keyword(s):  
Southern Oscillation ◽  
Survival Rates ◽  
Central Pacific ◽  
Climate Effect ◽  
Enso Events ◽  
Northeast Pacific ◽  
Management Actions ◽  
Local Survival ◽  
Portfolio Effect ◽  
Ocean Conditions

Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable—including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions.

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