scholarly journals Ecohydraulic Modelling to Support Fish Habitat Restoration Measures

2019 ◽  
Vol 11 (5) ◽  
pp. 1500 ◽  
Author(s):  
Ana Adeva-Bustos ◽  
Knut Alfredsen ◽  
Hans-Petter Fjeldstad ◽  
Kenneth Ottosson
Keyword(s):  
Habitat Restoration ◽  
Fish Habitat ◽  
Suitable Habitat ◽  
Physical Habitat ◽  
Concrete Wall ◽  
Main River ◽  
Before And After ◽  
General Improvement ◽  
Remote Sensing Techniques ◽  
Restoration Measures

Despite that hydromorphological restoration projects have been implemented since the 1940s, the key to improve the effectiveness of future restoration measures remains a challenge. This is in part related to the lack of adequate aims and objectives together with our limitations in understanding the effects on the physical habitat and ecosystems from interventions. This study shows the potential of using remote sensing techniques combined with hydraulic modelling to evaluate the success of physical restoration measures using habitat suitability as a quantifiable objective. Airborne light detection and ranging (LiDAR) was used to build a high-resolution two-dimensional model for Ljungan River, Sweden, using HEC-RAS 5.0. Two types of instream restoration measures were simulated according to the physical measures carried out in the river to improve salmonid habitat: (a) stones and rocks were moved from the bank sides to the main channel, and (b) a concrete wall was broken to open two channels to connect a side channel with the main river. Results showed that the hydraulic model could potentially be used to simulate the hydraulic conditions before and after instream modifications were implemented. A general improvement was found for the potential suitable habitat based on depth, velocity and shear stress values after the instream measures.

Fish Habitat: Essential Fish Habitat and Rehabilitation

1999 ◽  
Keyword(s):  
Lake Erie ◽  
Habitat Management ◽  
Fish Habitat ◽  
Learning By Doing ◽  
Suitable Habitat ◽  
Physical Habitat ◽  
Fish Stocks ◽  
Habitat Features ◽  
Fish Habitats

<em>Abstract.—</em> The quality and quantity of habitats determine ecosystem productivity. Hence, they determine the potential fish productivity that sustains the fish harvests extractable from freshwaters and seas. Efforts to conserve and protect fish habitats are frustrated by key unanswered questions: which habitat types and how much must be protected to ensure natural self-sustaining fish stocks? Minns and Bakelaar presented a prototype method for assessing suitable habitat supply for fish stocks in Lake Erie, an analysis that can be used to address conservation issues. Here, the method is refined and extended, taking the assessment of habitat supply for pike <em>Esox lucius </em> in the Long Point region of Lake Erie as a case study. As with the previous study, much emphasis is placed on “learning by doing.” Because available inventories of habitat features are coarse and incomplete, improved guidelines for estimating habitat supply are expected from these prototype studies. The habitat supply method previously presented by Minns and Bakelaar is elaborated in three ways here: (1) the basic physical habitat assessment is derived from a remote-sensing inventory database; (2) methods of quantifying the thermal regime and integrating it with other habitat elements are examined; (3) habitat supply estimates are used in a pike population model, and pike biomass and production are simulated for the Long Point region of Lake Erie and then compared with available records. The roles of error and uncertainty are examined for all elements in the estimation and application of suitable habitat supply values. There is potential for supply measurement and analysis to guide fish habitat management.

scholarly journals Waldbauliche Massnahmen für das Auerhuhn im Sonderwaldreservat Amden: ein erstes Fazit

2014 ◽  
Vol 165 (4) ◽  
pp. 87-96
Author(s):  
Nicolas Bircher ◽  
Harald Bugmann ◽  
Kurt Bollmann
Keyword(s):  
Habitat Restoration ◽  
Indirect Evidence ◽  
Canopy Cover ◽  
Ground Vegetation ◽  
Suitable Habitat ◽  
Forest Reserve ◽  
Species Response ◽  
Conservation Actions ◽  
Core Areas ◽  
Restoration Measures

Silvicultural habitat restoration measures for the capercaillie in the special forest reserve of Amden: a first review As a threatened forest grouse species, the capercaillie (Tetrao urogallus) depends on conservation actions in core areas of its Alpine distribution. In this study, we looked at the species' response to silvicultural measures in the special forest reserve of Amden in the canton of St. Gallen, Switzerland. Here, silvicultural measures were taken between 2006 and 2009 in stands that had previously been classified as less or not suitable for capercaillie. In summer 2010, we investigated how stands used by the species differed from unused ones by relating indirect evidence of species presence with forest structural and compositional variables. Evidence of species' habitat use was found in 12 out of 33 surveyed stands. Used stands showed a significantly higher share of bilberry in the ground vegetation layer, a higher proportion of coniferous trees and a lower canopy cover. Furthermore, the proportion of suitable habitat in immediate vicinity of the treated forest stand was higher in used stands. Our results support that habitat restoration by logging is a promising method to improve capercaillie habitat, in particular in fir-spruce forests, where the effectivity of restoration measures was higher compared to fir-beech forests. Hence, managing guidance for the future selection of stands for restoration should be based on habitat suitability of the stand itself and on an appropriate habitat quality of adjacent forest stands.

scholarly journals How effective is river restoration in re-establishing groundwater–surface water interactions? – A case study

2015 ◽  
Vol 19 (6) ◽  
pp. 2663-2672 ◽  
Author(s):  
A.-M. Kurth ◽  
C. Weber ◽  
M. Schirmer
Keyword(s):  
Surface Water ◽  
River Restoration ◽  
Morphological Changes ◽  
Cost Effective ◽  
Urban Stream ◽  
Distributed Temperature Sensing ◽  
River Bed ◽  
Before And After ◽  
Restoration Measures

Abstract. In this study, we investigated whether river restoration was successful in re-establishing groundwater–surface water interactions in a degraded urban stream. Restoration measures included morphological changes to the river bed, such as the installation of gravel islands and spur dykes, as well as the planting of site-specific riparian vegetation. Standard distributed temperature sensing (DTS) and novel active and passive DTS approaches were employed to study groundwater–surface water interactions in two reference streams and an experimental reach of an urban stream before and after its restoration. Radon-222 analyses were utilized to validate the losing stream conditions of the urban stream in the experimental reach. Our results indicated that river restoration at the study site was indeed successful in increasing groundwater–surface water interactions. Increased surface water downwelling occurred locally at the tip of a gravel island created during river restoration. Hence, the installation of in-stream structures increased the vertical connectivity and thus groundwater–surface water interactions. With the methods presented in this publication, it would be possible to routinely investigate the success of river restorations in re-establishing vertical connectivity, thereby gaining insight into the effectiveness of specific restoration measures. This, in turn, would enable the optimization of future river restoration projects, rendering them more cost-effective and successful.

Using confidence intervals to estimate the response of salmon populations (Oncorhynchus spp.) to experimental habitat alterations

2005 ◽  
Vol 62 (12) ◽  
pp. 2716-2726 ◽  
Author(s):  
Michael J Bradford ◽  
Josh Korman ◽  
Paul S Higgins
Keyword(s):  
Confidence Intervals ◽  
Effect Size ◽  
Null Hypothesis ◽  
Statistical Power ◽  
Habitat Restoration ◽  
Coho Salmon ◽  
Fish Habitat ◽  
Monitoring Program ◽  
Considerable Uncertainty ◽  
Monitoring Programs

There is considerable uncertainty about the effectiveness of fish habitat restoration programs, and reliable monitoring programs are needed to evaluate them. Statistical power analysis based on traditional hypothesis tests are usually used for monitoring program design, but here we argue that effect size estimates and their associated confidence intervals are more informative because results can be compared with both the null hypothesis of no effect and effect sizes of interest, such as restoration goals. We used a stochastic simulation model to compare alternative monitoring strategies for a habitat alteration that would change the productivity and capacity of a coho salmon (Oncorhynchus kisutch) producing stream. Estimates of the effect size using a freshwater stock–recruit model were more precise than those from monitoring the abundance of either spawners or smolts. Less than ideal monitoring programs can produce ambiguous results, which are cases in which the confidence interval includes both the null hypothesis and the effect size of interest. Our model is a useful planning tool because it allows the evaluation of the utility of different types of monitoring data, which should stimulate discussion on how the results will ultimately inform decision-making.

scholarly journals Estimating the effects of restoration on ecosystem services in the Haringvliet: Mapping current and future regulating ecosystem services

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Nikita Kopa-Ovdienko ◽  
Keyword(s):  
Water Management ◽  
Ecosystem Services ◽  
The Netherlands ◽  
Habitat Restoration ◽  
The State ◽  
Gis Mapping ◽  
Restoration Measures

To improve the state of the ecosystem of the Haringvliet, an estuary in the Southwest Delta of the Netherlands, the dam, which cuts off the estuary from the sea, will be opened a little in 2018. My research aims to quantify plausible changes of the ecosystem services supply following this water management modification and accompanying habitat restoration measures. For this purpose, values of ecosystem services supply for the relevant ecosystems were collected from the literature and GIS mapping was applied. The study shows clearly that the ecosystem services supply is expected to increase in general following the restoration scenarios. The results can be used for the planning of additional restoration measures aiming to provide the highest possible supply of the ecosystem services.

scholarly journals Habitat affinity and density-dependent movement as indicators of fish habitat restoration efficacy

2019 ◽  
Author(s):  
Carlos M. Polivka
Keyword(s):  
Behavioral Ecology ◽  
Habitat Restoration ◽  
Pacific Salmon ◽  
Fish Habitat ◽  
Explanatory Power ◽  
Habitat Characteristics ◽  
Density Data ◽  
Trade Offs ◽  
Effectiveness Studies ◽  
Habitat Affinity

AbstractConceptual and methodological tools from behavioral ecology can inform studies of habitat quality and their potential for evaluating habitat restoration in conservation efforts is explored here. Such approaches provide mechanistic detail in understanding the relationship between organisms and their habitats and are thus more informative than correlations between density and habitat characteristics. Several Pacific salmon species have been the target of habitat restoration efforts for the past 2-3 decades, but most post-restoration effectiveness studies have been limited to correlative data described above. In mark-recapture assays from four different study years, the affinity of sub-yearling Chinook salmon (Oncorhynchus tschawytscha) and steelhead (O. mykiss) for stream pools restored with or created by engineered log structures was greater than that for pools without restoration, though with high interannual variability. From corresponding distribution and density data, it was clear that habitat affinity data are not always concordant with single observations of density. The same was true of the correlation between either affinity or density and physical characteristics of pools, although depth and current velocity had some explanatory power for both responses in Chinook. Movement into pools by Chinook during the assays indicated that restored pools can support more immigrants at a given density than can unrestored pools; however no such pattern emerged for steelhead. Variation among individuals in body condition has implications for population-wide fitness, and such low variation was correlated with stronger affinity for pools in Chinook regardless of restoration status. This suggests that pools may mediate habitat-related trade-offs and that restoring them might have a positive effect on fitness. Thus affinity, immigration, and condition data give much-needed mechanistic indication of habitat selection for restored habitat via an apparent capacity increase and those potential fitness benefits. This is stronger support for restoration effectiveness than density differences alone because density data 1) may simply indicate redistribution of fish from poor to good habitats and 2) are not adequate to show correlations between restoration and positive change in traits correlated with fitness.

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