Search results for "Fish"
showing 10 items of 3164 documents
The valid genus name of the European freshwater blennies, Ichthyocoris or Salariopsis (Teleostei: Blenniidae)?
2022
Vecchioni, Luca, Arculeo, Marco, Hundt, Peter J., Marrone, Federico (2022): The valid genus name of the European freshwater blennies, Ichthyocoris or Salariopsis (Teleostei: Blenniidae)? Zootaxa 5162 (1): 99-100, DOI: https://doi.org/10.11646/zootaxa.5162.1.8
Control of a PTZ camera in a hybrid vision system
2014
In this paper, we propose a new approach to steer a PTZ camera in the direction of a detected object visible from another fixed camera equipped with a fisheye lens. This heterogeneous association of two cameras having different characteristics is called a hybrid stereo-vision system. The presented method employs epipolar geometry in a smart way in order to reduce the range of search of the desired region of interest. Furthermore, we proposed a target recognition method designed to cope with the illumination problems, the distortion of the omnidirectional image and the inherent dissimilarity of resolution and color responses between both cameras. Experimental results with synthetic and real …
Frisian as an Endangered Language: An Overview
2019
The main goal of the paper is to answer the questions whether Frisian can be referred to as an endangered language and if it managed to survive the constant influence of the surrounding larger cultures and languages. The first point to be analyzed is the geographic distribution of Frisian. The second issue to be considered is the historical and present cultural and social status of the Frisian language. The third matter to be analysed is the lexical variety of Frisian language and its complexity, which made its survival possible. The article takes the diachronic perspective and expounds upon all the mentioned factors and their role in the preservation of Frisian until today. The paper prese…
Complete Genome Sequence of Fish Pathogen Flavobacterium columnare Strain B185, Originating from Finland
2019
We report a complete genome sequence of a Finnish isolate of the fish pathogen Flavobacterium columnare. Using PacBio RS II sequencing technology, the complete circular genome of F. columnare strain B185 with 3,261,404 bp was obtained.
Testing a new rill flow resistance approach using the Water Erosion Prediction Project experimental database
2018
In this paper, a recently theoretically deduced rill flow resistance equation, based on a power‐velocity profile, was tested using the Water Erosion Prediction Project database. This database includes measurements of flow velocity, water depth, cross section area, wetted perimeter, and bed slope that were made in rills shaped on experimental sites distributed across the continental United States. In particular, three different experimental conditions (only rainfall, only flow, and rain with flow) were examined, and for each condition, the theoretically based relationship for estimating the Γ function of the power velocity profile was calibrated. The results established that (a) the Darcy‐We…
Land management impacts on soil properties and initial soil erosion processes in olives and vegetable crops
2020
Abstract This research aims to assess the impacts of soil use management on runoff, soil losses, and their main soil controls in vegetable cropland (CROP), tilled olives (OT), and grass-covered olive orchards (OGC) on Leptosol in Croatia. Soil analysis and rainfall simulation experiments were conducted to quantify runoff (Run), soil, and nutrient losses. Bulk density (BD) was significantly higher at OT plots, in addition to the CROP plots. Water-stable aggregates (WSA), mean weight diameter (MWD), and soil organic matter (OM) were significantly higher in OGC plots compared to the other land uses. Run and soil loss (SL) were significantly higher in CROP and OT plots compared to the OGC plots…
Influence of fish aggregating devices (FADs) on anti-predator behaviour within experimental mesocosms
2015
Commercial fishers have used fish aggregating devices throughout the Mediterranean Sea for over 40 years. These devices attract numerous predatory and forage species in both coastal and offshore environments. This study examined the influence of fish aggregating devices on schooling and aggregating behaviour by small forage fish in quasi-natural mesocosms. Anti-predator behaviour was evaluated for juvenile Caranx crysos under a variety of treatment conditions. Results suggest that, in the absence of physical structure, C. crysos first respond to a predatory threat by forming a school. When a physical structure is present, however, C. crysos show an occasional tendency to aggregate near the …
Contrasting structural complexity differentiate hunting strategy in an ambush apex predator.
2021
AbstractStructural complexity is known to influence prey behaviour, mortality and population structure, but the effects on predators have received less attention. We tested whether contrasting structural complexity in two newly colonised lakes (low structural complexity lake—LSC; high structural complexity—HSC) was associated with contrasting behaviour in an aquatic apex predator, Northern pike (Esox lucius; hereafter pike) present in the lakes. Behaviour of pike was studied with whole-lake acoustic telemetry tracking, supplemented by stable isotope analysis of pike prey utilization and survey fishing data on the prey fish community. Pike displayed increased activity, space use, individual …
Assessment of the efficacy of Artemia sp (Crustacea) cysts chorion as barrier to chlorpyrifos (organophosphorus pesticide) exposure. Effect on hatchi…
2005
In order to reveal the efficacy of the Artemia cysts chorion as barrier to the organophosphorus pesticide chlorpyrifos, whole and decapsulated cysts have been exposed to 10 mg L(-1) chlorpyrifos in sea water during hydration and hatching phase, separately. The concentration of chlorpyrifos in capsulated and decapsulated cysts after exposure has been determined in order to elucidate the efficacy of chorion as protection to the embryo. The results obtained demonstrate the ability of the cysts chorion to obstruct the pass of chlorpyrifos molecules through this protection structure. Thus, the concentration of chlorpyrifos in exposed decapsulated cysts is higher than in exposed whole cysts. More…
Whole-lake experiments reveal the fate of terrestrial particulate organic carbon in benthic food webs of shallow lakes
2014
Lake ecosystems are strongly linked to their terrestrial surroundings by material and energy fluxes across ecosystem boundaries. However, the contribution of terrestrial particulate organic carbon (tPOC) from annual leaf fall to lake food webs has not yet been adequately traced and quantified. In this study, we conducted whole-lake experiments to trace artificially added tPOC through the food webs of two shallow lakes of similar eutrophic status, but featuring alternative stable regimes (macrophyte rich vs. phytoplankton dominated). Lakes were divided with a curtain, and maize (Zea mays) leaves were added, as an isotopically distinct tPOC source, into one half of each lake. To estimate the …