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Dataset supporting the publication "Accuracy of coarse-resolution protocols for assessing fish passability at river infrastructure"
No full textDataset supporting the publication "Accuracy of coarse-resolution protocols for assessing fish passability at river infrastructure", Ecological Informatics (2024) https://doi.org/10.1016/j.ecoinf.2024.102575
The data is presented in excel file. Tab 1 "Existing_data_and_prot_scores" contains data on the 13 river barriers in England where existing telemetry data was available on fish passage efficiency. The barrier name / source ID are retained from the source literature for ease of cross-referencing. Fish length, barrier height, fish passage efficiency (telemetry score) and the two barrier passability scores (ICE and SNIFFER) are included. Note that some of the protocol passability scores deviate from the categories defined by the protocols. This is because the size range of fish for which passage efficiency data were available did not always match that for which the protocol passability scores was generated. In these instances, the mean score of the protocol groups for which telemetry data were available was used in the analysis and presented here. Tab 2 "Prot_scores_for_species" contains the coarse-resolution rapid barrier assessment protocol scores (for both ICE and SNIFFER) for each barrier for Adult trout, Adult grayling, Adult lamprey and Juvenile salmonids.
This project was funded by the Horizon 2020 AMBER (Adaptive Management of Barriers in European Rivers) project (no. 689682). </span
Masking a fish's detection of environmental stimuli: application to improving downstream migration at river infrastructure
No full textAccording to Signal Detection Theory, the ability to detect a stimulus (discriminability, d') is inversely related to the magnitude of internal and external noise. In this study, downstream moving brown trout Salmo trutta were used to investigate whether external hydrodynamic noise (in this case turbulence) could mask a signal that induced an unwanted response, such as rejecting accelerating velocity gradients commonly encountered at entrances to fish bypass channels. S. trutta behaviour was quantified in the absence (control) or presence of an accelerating velocity gradient created by an unconstricted or constricted channel, respectively, under two levels (low and high) of background turbulent kinetic energy (hydrodynamic noise). Experiments were conducted in an indoor recirculating flume in the dark and a range of passage metrics were quantified. Under the control condition, most (ca. 91%) S. trutta passed, usually oriented downstream (67%), with minimal delay (median 0.13 min). In comparison, fewer S. trutta (ca. 43%) passed under constricted conditions, they tended to orient facing into the flow (ca. 64%) and delay was greater (median > 20 min). When viewed from a coarse-scale perspective, discriminability of the velocity gradient was lower when turbulence was high suggesting masking of the signal occurred. However, the resulting increase in the percentage of fish that passed, decrease in time to pass and reduction in the distance at which S. trutta reacted (switched orientation) was subtle and non-significant. Despite the mixed results obtained, the use of masking to manipulate an animal's perception of environmental stimuli as a fisheries management tool is conceptually valid and the results of this experiment present a useful stepping stone for future research.</p
Accuracy of coarse-resolution protocols for assessing fish passability at river infrastructure
No full textRiver infrastructure can present a major barrier to fish movement. While mitigation can be achieved through infrastructure removal or modification, e.g. construction of fish passes, prioritising this work to maximise ecological benefit within budgetary and other constraints remains a substantial management challenge. Several coarse-resolution rapid barrier assessment protocols have been developed to estimate fish passability at river infrastructure to aid decision making in relation to catchment scale barrier management. The outputs of these protocols are rarely validated against empirical data, such as that provided by telemetry or other methods of tracking fish, limiting confidence in whether they provide realistic estimates of fish passability. In this study, the accuracy of two barrier passability assessment protocols yet to be validated against empirical data, SNIFFER and ICE, developed in the UK and France, respectively, was assessed by: 1) collating available empirical multi-species fish passage data at river infrastructure, 2) undertaking field surveys at each structure to quantify SNIFFER and ICE passability scores, and 3) comparing the fish passage data with the estimated passability scores. Fish passage data were obtained for four species (Salmo trutta, Cottus gobio, Lampetra fluviatilis and Thymallus thymallus) and five barrier types (sloped weir, culvert, rock ramp, nature-like bypass, and some classified as ‘complex’) at thirteen sites in England. Both protocols suggest these barriers are a major impediment to upstream moving fish as a classification of ‘impassable’ was the most common. However, agreement between protocols was low for barriers considered ‘high impact’, ‘low impact’ or ‘easily passable’. When compared with empirical fish passage data, there was a positive relationship with the passability scores predicted by SNIFFER, but the protocol tended to be conservative. There was no relationship between the empirical fish passage data and the passability scores predicted by ICE, although field surveys were undertaken outside of the recommended discharge range which may have influenced accuracy. This study provides the first partial validation of two barrier passability assessment protocols and suggests that further detailed validation is needed to calibrate the passability scores and enhance confidence in the planning tools (e.g. optimisation models) that utilise their outputs.</p
Comparison of coarse-resolution rapid methods for assessing fish passage at riverine barriers: ICE and SNIFFER protocols
No full textMan-made barriers have led to river fragmentation, restricting fish migrations to critical habitat. Fragmentation is relevant to the Water Framework and Habitats (Annex II fish) Directives of the European Union. SNIFFER (Water Framework Directive 111) is a United Kingdom-developed fish passability assessment method with passability scores based on published data describing the physiological abilities of different fish species/life stages. SNIFFER is an objective protocol, but final scores require assessor opinion on specific nonquantified elements. The French ICE fish passability assessment protocol covers a larger number of fish species/life stages and removes the requirement for velocity readings (except in a few situations) and expert opinion with assessors following a decision tree process. In most situations, fewer direct measurements are required for the ICE protocol, and the evaluation process is quicker and simpler. Both protocols utilize a similar passability scoring system (0 = total barrier, 0.3 = high impact, 0.6 = low impact, 1 = no risk). Comparison of outcomes for species categories for both protocols was made in paired comparisons for 112 transversal sections (fish passage routes) recorded at 52 barriers (in-river structures) of varying complexity in Irish rivers. Overall scores were found to be in high agreement for species groups at impassable (Score 0) and no risk (Score 1) barriers. Protocol agreement dropped significantly for high-impact (Score 0.3) and low-impact (Score 0.6) barriers. Results are discussed in the context of barrier passability at the 52 structures examined, primarily in the context of Atlantic salmon (Salmo salar L.) and of sea lamprey (Petromyzon marinus L.). In total, 22 of the structures had one or more fishways or fish passage solutions built into them as part of the original design. Both protocols identified substantial problems for sea lamprey and adult salmon at the majority of the fish passage solutions surveyed. The merits and shortcomings of both protocols, for managers assessing fish passability at complex riverine structures, are discussed.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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