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1. Predation on schooling fish is shaped by encounters between prey during school formation using an Ideal Gas Model of animal movement.

Author:
Derrick T. de Kerckhove; Brian J. Shuter
Source:
Ecological modelling 2022 pp. 110008
ISSN:
0304-3800
Subject:
stocking rate,   etc   ; forage fish; models; predation;     Show all 4 Subjects
Abstract:
... Fish schools reduce their predators' encounter rates not only by performing evasive maneuvers but also by increasing distances between prey patches. However, a similar challenge applies to isolated prey fish seeking refuge during periods of diel school formation. We demonstrate with an Ideal Gas movement model that as the stock sizes of a fish who forms schools daily decreases, school densities do ...
DOI:
10.1016/j.ecolmodel.2022.110008

2. Productivity and Management of Renewable Resources: Why More Efficient Fishing Fleets Should Fish Less

Author:
Eric Nævdal
Source:
Environmental and resource economics 2022 v.81 no.3 pp. 409-424
ISSN:
0924-6460
Subject:
stocking rate,   etc   ; environmental economics; fish; fisheries management; renewable resources; resource management;     Show all 6 Subjects
Abstract:
... This article analyses the effect of productivity improvements on optimal fisheries management. It is shown that when harvest costs are independent of resource stock and the stock is below its steady state level, then for any given stock it is optimal to reduce harvest levels in response to a productivity increase unless optimal harvest rate is already zero. If harvest costs are stock dependent thi ...
DOI:
10.1007/s10640-021-00633-2

3. Fast Somatic Growth May Cause Recruitment Overfishing in Vendace (Coregonus albula) Gillnet Fisheries

Author:
Thomas Wanke; Uwe Brämick; Thomas Mehner
Source:
Annales zoologici Fennici 2021 v.58 no.4-6 pp. 271-287
ISSN:
0003-455X
Subject:
stocking rate,   etc   ; Coregonus; egg production; fecundity; gillnets; lakes; mortality; risk;     Show all 8 Subjects
Abstract:
... Vendace is commonly assumed at low risk to recruitment overfishing. This assumption has been confirmed for boreal stocks but might not apply at lower latitudes. We evaluated the risk of recruitment overfishing at the southernmost extent of vendace populations by comparing fecundity, natural mortality, and fishing mortality of two stocks differing in growth with those of a population not subject to ...
DOI:
10.5735/086.058.0412

4. Maturation in the Barents Sea capelin – Contrasting length- and gonad-based metrics

Author:
N.O.A.S. Jourdain; E. Fuglebakk; S. Subbey
Source:
Fisheries research 2021 v.237 pp. 105880
ISSN:
0165-7836
Subject:
stocking rate,   etc   ; Mallotus villosus; fish; research; time series analysis; uncertainty; Barents Sea;     Show all 7 Subjects
Abstract:
... It is assumed that maturation in the Barents Sea capelin is length-dependent, and that fish of at least 14 cm will potentially spawn. Current assessment and management models for the stock are based on this assumption of constant maturity at length (MaL). Using data from scientific surveys, this paper examines the validity of the constant MaL assumption, and contrasts it with maturation based on e ...
DOI:
10.1016/j.fishres.2021.105880

5. Space use by semi‐free‐ranging cows on wetlands and its implication as a conservation management tool

Author:
Paweł Mirski
Source:
Restoration ecology 2022 v.30 no.3 pp. e13533
ISSN:
1061-2971
Subject:
stocking rate,   etc   ; autumn; ecological restoration; herds; landscapes; national parks; shrubs; spring; summer; wetlands;     Show all 10 Subjects
Abstract:
... Wetlands are often exposed to reed and shrub expansion that dominate their heterogeneous landscape and threaten species inhabiting open wetlands. The alternative to heavy‐machine mowing is grazing, which should be carried out without fencing in high‐value protected areas. To evaluate the effectiveness of semi‐free‐ranging cattle in sustaining and restoring the open landscape of heterogeneous wetla ...
DOI:
10.1111/rec.13533

6. Comparative Pasture Management on Canadian Cattle Ranches With and Without Adaptive Multipaddock Grazing

Author:
Edward W. Bork; Timm F. Döbert; Jessica S.J. Grenke; Cameron N. Carlyle; James F. Cahill; Mark S. Boyce
Source:
Rangeland ecology & management 2021 v.78 pp. 5-14
ISSN:
1550-7424
Subject:
stocking rate,   etc   ; cattle; ecosystems; forage; grasslands; greenhouses; pasture management; pastures; rangelands; soil carbon; Canada;     Show all 11 Subjects
Abstract:
... Significant interest exists in the potential for specialized grazing systems, including adaptive multipaddock (AMP) grazing, to enhance grassland health and function. However, specific pasture management practices associated with AMP grazing at the ranch level remain poorly understood in comparison with more regionally representative management systems. As part of a larger study examining grazing ...
DOI:
10.1016/j.rama.2021.04.010

7. Fisheries management under incomplete information by optimal stochastic control and Hidden Markov Model filter

Author:
Xi Chen
Source:
Fisheries research 2021 v.243 pp. 106047
ISSN:
0165-7836
Subject:
stocking rate,   etc   ; Markov chain; biomass; economic performance; fish; fisheries; issues and policy; research; uncertainty;     Show all 9 Subjects
Abstract:
... This paper deals with mathematical modelling of strategies in harvesting of fish populations. Since too aggressive harvesting may have severe consequences, a cautious control of the process is called for. The determination of optimal harvesting based on the biomass size is made even more challenging since there is considerable uncertainty in the estimation of the stock size, the so-called incomple ...
DOI:
10.1016/j.fishres.2021.106047

8. A bioeconomic model of a fishery with saturated catch and variable price: Stabilizing effect of marine reserves on fishery dynamics

Author:
Ali Moussaoui; Pierre Auger
Source:
Ecological complexity 2021 v.45 pp. 100906
ISSN:
1476-945X
Subject:
stocking rate,   etc   ; bioeconomic models; equations; prices;     Show all 4 Subjects
Abstract:
... In this paper, we study a mathematical bio-economic model of a fishery with varying price. The three dimensional model describes the time evolution of the resource, the fishing effort and the price. The model is original because it considers a nonlinear harvesting function assumed to depend upon stock size and fishing effort with a saturation effect with respect to the resource as well as a price ...
DOI:
10.1016/j.ecocom.2020.100906

9. Carbon stocks differ among land-uses in agroforestry systems in western Canada

Author:
Zilong Ma; Edward W. Bork; Cameron N. Carlyle; Jonathan Tieu; Cole D. Gross; Scott X. Chang
Source:
Agricultural and forest meteorology 2022 v.313 pp. 108756
ISSN:
0168-1923
Subject:
stocking rate,   etc   ; carbon; carbon sinks; climate change; cropland; food security; forests; grasslands; humus; land use; meteorology; mineral soils; overstory; silvopastoral systems; species diversity; sustainable land management; tree age; trees; understory; Alberta;     Show all 20 Subjects
Abstract:
... Agroforestry systems (AFS) are increasingly being recognized as sustainable land-use systems that can increase carbon (C) sequestration and improve food security. However, the relative contributions of various C pools to the overall C stock of AFS and their dependence on factors such as tree age, species diversity and density is still unclear in many regions. Using an equivalent soil mass approach ...
DOI:
10.1016/j.agrformet.2021.108756

10. Canopy characterization of sweet chestnut coppice in the north of spain from lidar data

Author:
Marta Prada; Elena Canga; Juan Majada; Celia Martínez-Alonso
Source:
European journal of forest research 2022 v.141 no.2 pp. 267-279
ISSN:
1612-4669
Subject:
stocking rate,   etc   ; Castanea sativa; canopy; coppicing; ecosystems; forest management; forests; leaf area index; lidar; linear models; research;     Show all 11 Subjects
Abstract:
... The Leaf Area Index (LAI) is a key parameter that helps to understand the connection between canopy structure and ecosystem functions. In this study, the main aims were to examine the impact of forest management on canopy structure using LiDAR data to characterize the canopy vertical profile, as well as to develop LAI models and an LAI mapping tool for sweet chestnut (Castanea Sativa Mill.) coppic ...
DOI:
10.1007/s10342-021-01436-2

11. Spruce (Picea abies L.) planting leads post-clearcut bird assemblages to a novel successional pathway—a comparative study in hemiboreal mixed forests

Author:
Eliisa Pass; Raido Kont; Asko Lõhmus
Source:
Annals of forest science 2022 v.79 no.1 pp. 20
ISSN:
1286-4560
Subject:
stocking rate,   etc   ; Picea abies; birds; comparative study; dead wood; habitats; landscapes; silviculture; species diversity; stand age; stand development; Estonia;     Show all 12 Subjects
Abstract:
... KEY MESSAGE: Bird assemblages in planted spruce (Picea abies L.) forests were compositionally distinct from those in naturally regenerated mixed stands. Despite rapid stand development on productive soils, even-aged silviculture cannot host most old-forest species. However, their habitat quality could be supported in landscape mosaics with retention forestry and set-asides. CONTEXT: The most produ ...
DOI:
10.1186/s13595-022-01138-8

12. Spatial characterization of construction material stocks: The case of the Paris region

Author:
Vincent Augiseau; Eunhye Kim
Source:
Resources, conservation, and recycling 2021 v.170 pp. 105512
ISSN:
0921-3449
Subject:
stocking rate,   etc   ; circular economy; construction materials; data quality; energy; urbanization;     Show all 6 Subjects
Abstract:
... Better knowledge of the spatial distribution of anthropogenic stocks is key for the implementation of circular economy policies. This article focuses on the case of construction materials in the Paris region in 2013. A bottom-up approach using GIS modeling is applied to estimate and locate the stocks of 27 materials and 24 building archetypes, three transport networks and six energy and water netw ...
DOI:
10.1016/j.resconrec.2021.105512

13. Examination of information release on return volatility: A market and sectoral analysis

Author:
Mason Prasad; Walid Bakry; Maria Estela Varua
Source:
Heliyon 2020 v.6 no.5 pp. e03885
ISSN:
2405-8440
Subject:
stocking rate,   etc   ; Australians; data collection; exhibitions; market analysis; markets; prices;     Show all 7 Subjects
Abstract:
... This paper examines the role of information release in explaining the return volatility of the Australian equity market. The study applies proxies of greater accuracy to examine the effect of public and private information on return volatility. Analyst price targets (PTR) and Morningstar stock star ratings (MSR) were used as private information proxies while Australian Securities Exchange (ASX) an ...
DOI:
10.1016/j.heliyon.2020.e03885

14. Stocking density and rearing environment affect external condition, gonad quantity and gonad grade in onshore sea urchin roe enhancement aquaculture

Author:
Fletcher Warren-Myers; Stephen E. Swearer; Kathy Overton; Tim Dempster
Source:
Aquaculture 2020 v.515 pp. 734591
ISSN:
0044-8486
Subject:
stocking rate,   etc   ; Strongylocentrotus purpuratus; aquaculture; aquaculture industry; cages; infrastructure; rearing;     Show all 7 Subjects
Abstract:
... Finding the ideal density to optimise growth, health and welfare of aquaculture species reared in cage or tank environments allows farmers to produce the best quality product per unit area. Appropriate stocking densities are well known for most major aquaculture species, but limited information exists for the developing sea urchin aquaculture industry. The temperate purple sea urchin Heliocidaris ...
DOI:
10.1016/j.aquaculture.2019.734591

15. Selectivity metrics for fisheries management and advice

Author:
Paraskevas Vasilakopoulos; Ernesto Jardim; Christoph Konrad; Dominic Rihan; Alessandro Mannini; Cecilia Pinto; John Casey; Iago Mosqueira; Finbarr G. O’Neill
Source:
Fish and fisheries 2020 v.21 no.3 pp. 621-638
ISSN:
1467-2960
Subject:
stocking rate,   etc   ; fish; mortality;     Show all 3 Subjects
Abstract:
... Fisheries management typically aims at controlling exploitation rate (e.g., Fbar) to ensure sustainable levels of stock size in accordance with established reference points (e.g., FMSY, BMSY). Population selectivity (“selectivity” hereafter), that is the distribution of fishing mortality over the different demographic components of an exploited fish stock, is also important because it affects both ...
DOI:
10.1111/faf.12451

16. Effects of Forestry Transformation on the Landscape Level of Biodiversity in Poland’s Forests

Author:
Ewa Referowska-Chodak; Bożena Kornatowska
Source:
Forests 2021 v.12 no.12 pp. -
ISSN:
1999-4907
Subject:
stocking rate,   etc   ; biodiversity; clearcutting; forests; habitat fragmentation; landscapes; politics; socialism; wood; Poland;     Show all 10 Subjects
Abstract:
... At all times, historical, political, economic, and social factors have affected the management of forests, with direct and indirect effects on the landscape. This study aimed to trace the impact of Poland’s forestry evolution over the last 75 years (1945–2020) on forest biodiversity at the landscape level. Five indicators were selected (forest area, forest fragmentation, protected forests, protect ...
DOI:
10.3390/f12121682

17. Efficiency estimates from depletion experiments for sedentary invertebrates: evaluation of sources of uncertainty in experimental design

Author:
Leanne M. Poussard; Eric N. Powell; Daniel R. Hennen
Source:
Fisheries research 2021 v.234 pp. 105806
ISSN:
0165-7836
Subject:
stocking rate,   etc   ; Arctica islandica; Spisula solidissima; experimental design; models; research; surveys; uncertainty;     Show all 8 Subjects
Abstract:
... Between 1997 and 2011, The National Marine Fisheries Service conducted 50 depletion experiments to estimate survey gear efficiency and stock density for Atlantic surfclam (Spisula solidissima) and ocean quahog (Arctica islandica) populations using commercial hydraulic dredges. A model formulated for this purpose, the Patch Model, was used to estimate gear efficiency and organism density. The range ...
DOI:
10.1016/j.fishres.2020.105806

18. Prospects for a saturation of humanity’s resource use? An analysis of material stocks and flows in nine world regions from 1900 to 2035

Author:
Dominik Wiedenhofer; Tomer Fishman; Barbara Plank; Alessio Miatto; Christian Lauk; Willi Haas; Helmut Haberl; Fridolin Krausmann
Source:
Global environmental change 2021 v.71 pp. 102410
ISSN:
0959-3780
Subject:
stocking rate,   etc   ; USSR; energy efficiency; global change; industrialization; infrastructure; metabolism; models; China;     Show all 9 Subjects
Abstract:
... Material stocks in infrastructure, buildings and machinery shape current and future resource use and emissions. Analyses of specific countries and selected materials suggest that material stocks might saturate, which would be important for a more sustainable social metabolism. However, it is unclear to what extent the evidence holds for a wider range of stocks and flows, as well as for world regio ...
DOI:
10.1016/j.gloenvcha.2021.102410

19. Effects of stocking density on large white, commercial tom turkeys reared to 20 weeks of age: 1. growth and performance

Author:
B.M. Bartz; K.A. Anderson; E.O. Oviedo-Rondón; K. Livingtson; J.L. Grimes
Source:
Poultry science 2020 v.99 no.11 pp. 5582-5586
ISSN:
0032-5791
Subject:
stocking rate,   etc   ; Large White; body weight; industry; males; rearing; regression analysis; turkeys;     Show all 8 Subjects
Abstract:
... Industry standards for turkey stocking densities are variable and may not represent the more rapidly growing strains currently available. Therefore, a study was completed to evaluate 4 stocking densities: a nominal density (0.3525 m²/bird), 10% tighter density (0.3169 m²/bird), 10% looser density (0.3882 m²/bird), and 20% looser density (0.4238 m²/bird) on the effects on large white, commercial ma ...
DOI:
10.1016/j.psj.2020.08.024

20. Data-limited stock assessment of two horse mackerel species (Trachurus mediterraneus and T. trachurus) from the Mediterranean coast of Turkey

Author:
Cemal Turan
Source:
Regional studies in marine science 2021 v.44 pp. 101732
ISSN:
2352-4855
Subject:
stocking rate,   etc   ; growth performance; mackerel; marine science; mortality; yield forecasting; Mediterranean region;     Show all 7 Subjects
Abstract:
... A preliminary assessment of stock size and status of Trachurus mediterraneus and T. trachurus species were investigated via virtual population and yield prediction analyses using onboard collected length-frequency data from Northeastern Mediterranean. The length-frequency based VBGF parameters and growth performance index were L∞=28 cm, k=0.62, t0=0.58, tanc=0.52 and Φ′=2.69 for T. mediterraneus a ...
DOI:
10.1016/j.rsma.2021.101732