References of "Nzau Matondo, Billy"
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See detailDynamics of upstream movements of the European eel Anguilla anguilla in an inland area of the River Meuse over the last 20 years
Nzau Matondo, Billy ULg; Ovidio, Michaël ULg

in Environmental Biology of Fishes (2016)

The dynamics of upstream movements of the yellow eel Anguilla anguilla were investigated at Lixhe on the Belgian River Meuse in an inland fish pass regularly monitored from 1992 to 2014. Based on a ... [more ▼]

The dynamics of upstream movements of the yellow eel Anguilla anguilla were investigated at Lixhe on the Belgian River Meuse in an inland fish pass regularly monitored from 1992 to 2014. Based on a constant year-to-year sampling effort, we examined the abundance of ascending yellow eels and their body size, seasonal movement, and the associated water temperature and flow. Over the last 23 years, the number of ascending yellow eels has declined at an average 4.2% per year since 1992. The abundance of eels in 2014 is estimated at 4.5% of the ascending stock in 1992. We observed that some annual variations in eel abundance at Lixhe might be related to opening fish passes downstream of the study site. The results clearly demonstrated that long-term declining abundance of eels has resulted in increased sizes (mean increase, 4.1 mm per year since 1992) and temperatures triggering the upstream movement process (1.03°C per decade), with earlier dates for the last eel passages reducing the difference between temperature extremes of eel passages through the fish pass during the migration season. Eel movements occurred in spring and summer at low river discharge and were mainly triggered by high-temperature events. Eels have become larger with time because of improved feeding opportunities and more growth habitats available resulting from the long-term reduction in recruitment. This study highlights the importance of investigating long time spans for a better comprehension of the changes observed in yellow eels and for the optimization of management measures and future research. [less ▲]

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See detailAn overview of potamodromous fish upstream movements in medium-sized rivers, by means of fish passes monitoring
Benitez, Jean-Philippe ULg; Nzau Matondo, Billy ULg; Dierckx, Arnaud ULg et al

in Aquatic Ecology (2015), 49(4), 481-497

This study aims to investigate the upstream movement patterns of potamodromous fish species using multi-annual monitoring of modern multi-species fish passes in two medium-sized Belgian rivers: the ... [more ▼]

This study aims to investigate the upstream movement patterns of potamodromous fish species using multi-annual monitoring of modern multi-species fish passes in two medium-sized Belgian rivers: the Berwinne and the Amble`ve. During a 6-year monitoring period including a frequency of 1–5 times per week, the captured individuals were identified, measured and weighed to determine species abundance, and the periodicity of their seasonal movement patterns was investigated in relation to environmental factors. In the Amble`ve, 22 different fish species were monitored (n = 1513 individuals; biomass of 154 kg) and 14 species in the Berwinne (n = 3720; 408 kg). In both fish passes, inter-annual differences were observed, but the first year of monitoring was the best in terms of biomass, indicating the existence of an opening effect just after the fish passes opening, which allowed new migration routes. Salmonids and rheophilic cyprinids were predominant in terms of biomass, while minnow and spirlin were predominant in terms of number of fishes. The diversity in sizeranged from 46 to 760 mm demonstrating the importance of movements in various life stages. The capture periodicity showed different mobility patterns between the adult and juvenile stages in most species. Movements occurred frequently during the circus reproduction period for some species, but many species moved also apart from spawning period. This study highlights the omnipresence of patrimonial holobiotic potamodromous fish at different life stages that reflect their biological needs to move throughout the annual cycle. They must be considered as target species in river continuity restoration programmes and fish-pass design. [less ▲]

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See detailEvaluation de la qualité biologique des rivières wallonnes sur base des indices biologiques poissons. Support technique aux inventaires 2015.
Rimbaud, Gilles ULg; Ovidio, Michaël ULg; Dierckx, Arnaud ULg et al

Report (2015)

L’Université de Liège (LDPH) a effectué le travail décrit dans ce rapport pour le compte du Service public de Wallonie qui a financé ce projet dans le cadre d’une convention ayant pour objectif ... [more ▼]

L’Université de Liège (LDPH) a effectué le travail décrit dans ce rapport pour le compte du Service public de Wallonie qui a financé ce projet dans le cadre d’une convention ayant pour objectif l’évaluation de la qualité biologique des eaux de surface basée sur les indices biologiques « poissons » dans quatorze cours d’eau de Wallonie. Cette mission s’inscrit dans le contexte de la mise en oeuvre de la Directive 2000/60/CE établissant un cadre pour une politique communautaire dans le domaine de l’eau. [less ▲]

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See detailShort-term responses of glass eels transported from UK to small Belgian streams
Ovidio, Michaël ULg; Tarrago-Bes, Frédérique; Nzau Matondo, Billy ULg

in Annales de Limnologie = International Journal of Limnology (2015), 51(3), 219-226

Restocking of inland waters with glass eels is one of the recovery options to prevent the decline of European eel Anguilla anguilla (L.) populations. We studied the growth, dispersion, density and habitat ... [more ▼]

Restocking of inland waters with glass eels is one of the recovery options to prevent the decline of European eel Anguilla anguilla (L.) populations. We studied the growth, dispersion, density and habitat preferences in the imported glass eels from United-Kingdom and stocked in three typologically different small Belgian streams, using electrofishing surveys around the single release point, 1 year following stocking. Our results clearly support that the recaptured individuals stocked in our streams farther from the sea, survived, grew, dispersed upstream and downstream. Elvers exploited the complete transversal section of stream, with preference for the sheltered microhabitats near the banks with slower water velocity and low depth. Length-weight relationship was different between streams in terms of allometric coefficient (b). We assume that microhabitats and food availabilities lead to contrasted results in terms of growth and absolute occurrence. Restocking of glass eels in small middle-land streams was found to be an interesting and unconventional option that requires adequate stream and habitat selection. [less ▲]

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See detailHistorical evolution of fish biodiversity and capture periodicity in the River Meuse (Belgium) as revealed by 15 consecutive years of fishpass monitoring
Benitez, Jean-Philippe ULg; Dierckx, Arnaud ULg; Nzau Matondo, Billy ULg et al

Conference (2015, June)

In the River Meuse at 323km upstream from the North Sea, the hydroelectric dam of Lixhe (rated power of 5300KW) is equipped with two fishpasses: one pool and weir fishpass (in operation since 1980; 0.13m³ ... [more ▼]

In the River Meuse at 323km upstream from the North Sea, the hydroelectric dam of Lixhe (rated power of 5300KW) is equipped with two fishpasses: one pool and weir fishpass (in operation since 1980; 0.13m³.s-1 operating flow) and one vertical slot fishpass (in operation since 1998; 1m3.s-1 operating flow). Both fishpasses were scientifically monitored using capture traps during 15 consecutive years (from 1999 to 2014). The objective of the study is to analyse i) the evolution of fish stock and biodiversity over 15 years and ii) the capture periodicity of fish and it’s variation over years. During the considered period, we observed 36 species at adult stage (88597 individuals with 75% of cyprinids) and 13 species at juvenile (0+) stage (335067 individuals with 90% of cyprinids). Global results between 1999 and 2014 showed a drastic reduction in capture per year (>90%) for some species like Anguilla Anguilla, Alburnus alburnus, Blicca bjoerkna, Rutilus rutilus and Tinca tinca. Whereas other species have emerged like Aspius aspius and Silurus glanis. For the 0+, an important interannual variation is observed from few individuals to several tens of thousands per year. The comparison between both fishpasses indicated a greater use (>50%) of the vertical slot fishpass by rheophilic species and species that have good swimming ability. The analysis of capture periodicity for the most abundant species at adult stage demonstrated the presence of stable behaviours between years for the Abramis abrama and B. bjoerkna respectively a Q50 of the capture day of the year from 108th to 144th day at mean=17°C and from 118th to 155th day at mean=18°C. In contrast other species have patterns more variables (Barbus barbus: Q50 from 96th to 266th day; R. rutilus: from 10th and 309th day). Finally the 0+ exhibited a capture periodicity stable in time during the summer. [less ▲]

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See detailDoes yellow eel prefer old pool and weir or new vertical slot fish pass during their upstream migration?
Nzau Matondo, Billy ULg; Dierckx, Arnaud ULg; Benitez, Jean-Philippe ULg et al

Conference (2015, June)

The hydroelectric dam of Lixhe in the River Meuse, 323km upstream from the North Sea at the entry of Belgium near the frontier with the Netherlands is equipped with two basin fish-passes: – the old pool ... [more ▼]

The hydroelectric dam of Lixhe in the River Meuse, 323km upstream from the North Sea at the entry of Belgium near the frontier with the Netherlands is equipped with two basin fish-passes: – the old pool-and-weir configuration (OFP) operates at low discharge (0.13m3/s) and – the new vertical-slot configuration (NFP) operating at high discharge (1m3/s) with attraction flow (1.5m3/s). However, the utilization rate of these fish-passes by the incoming yellow eels remains unknown, because the trap of NFP is not adapted to retain anguillids and small species. Yet, such knowledge is crucial to improve the inland colonization of the species and to increase our understanding of fish-pass utilization given its particular swimming mode. In season 2013, eels caught two times a week using a cone-trap pool in the OFP and net traps in the NFP, were tagged and released the same day 0.3km downstream (n = 396eels). The utilization of OFP and NFP was studied using automatic RFID transponder detection antennas placed in upstream basins of the fish-passes, during years 2013 and 2014. Results revealed that the OFP was the preferred migration route of eels (eel numbers, OFP:NFP, 2013= 88:51 and 2014= 41:16, χ²-test, p<0.0001), which was also used earlier in season. Eels displayed fidelity to their catch fish-passes (>70% of the detected eels, annually). Detection rate was high in the year of eel tagging (2013: 35.1%) before decreasing in the following year (2014: 14.4%). Eels used these fish-passes the night from 22:00 to 04:00, at 14-26°C, river flow <200m³/s and whenever waxing and waning phases of moonlight. Our results provide insight into the utilization of fish-passes by migrating eels. The study suggests further reflection before removing the old fish-pass in large rivers and to think about the eel attractiveness and comfort when the construction of a new fish pass is planned. [less ▲]

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See detailEstimation de l’abondance du stock des anguilles recrutées par migration de remontée dans la Meuse en Wallonie et réalisation des essais de repeuplement en juvéniles. Rapport final du projet financé par le Fonds européen pour la Pêche (Code projet: 32-1102-002)
Nzau Matondo, Billy ULg; Philippart, Jean-Claude ULg; Dierckx, Arnaud ULg et al

Report (2015)

Ce rapport final présente les résultats des recherches menées par le Laboratoire de Démographie des Poissons et d’Hydroécologie (LDPH) de l’Unité de Biologie du comportement dans le cadre d’un projet co ... [more ▼]

Ce rapport final présente les résultats des recherches menées par le Laboratoire de Démographie des Poissons et d’Hydroécologie (LDPH) de l’Unité de Biologie du comportement dans le cadre d’un projet co-financé par le Fonds Européen pour la Pêche (FEP) et le Service Public de Wallonie, Département de la Nature et des Forêts (code projet : 32-1102-002) intitulé «Estimation de l’abondance du stock des anguilles recrutées par migration de remontée dans la Meuse en Wallonie et réalisation des essais de repeuplement en juvéniles. » [less ▲]

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See detailConvention relative à la réhabilitation du Saumon atlantique dans le bassin de la Meuse (Rapport 2014-2015)
Ovidio, Michaël ULg; Dierckx, Arnaud ULg; Benitez, Jean-Philippe ULg et al

Report (2015)

Le présent rapport d’activités intègre les travaux des deux équipes universitaires de Namur et de Liège dans la cadre de la convention relative à la réhabilitation du saumon atlantique dans le bassin de ... [more ▼]

Le présent rapport d’activités intègre les travaux des deux équipes universitaires de Namur et de Liège dans la cadre de la convention relative à la réhabilitation du saumon atlantique dans le bassin de la Meuse au cours de la période février 2014- janvier 2015 [less ▲]

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See detailEvaluation de la qualité biologique des rivières wallonnes sur base des indices biologiques poissons. Support technique aux inventaires 2014.
Rimbaud, Gilles ULg; Ovidio, Michaël ULg; Dierckx, Arnaud ULg et al

Report (2014)

Ce rapport final présente les résultats des inventaires piscicoles effectués en juin-juillet et en septembre-octobre 2014 ainsi que le calcul des indices biologiques « poissons » (IBIP et EFI).

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See detailUsing intensive multiyear fish-pass monitoring to analyse seasonal upstream movement patterns of patrimonial holobiotic potomadromous fish species in a medium size river
Benitez, Jean-Philippe ULg; Nzau Matondo, Billy ULg; Dierckx, Arnaud ULg et al

in Proceedings of the 10th International Conference on Ecohydraulics (2014, June)

Belgian rivers are fragmented by numerous obstacles which considerably limit the free access of fish to functional habitats. Fish-passes are major tools used to increase stream continuity and improve ... [more ▼]

Belgian rivers are fragmented by numerous obstacles which considerably limit the free access of fish to functional habitats. Fish-passes are major tools used to increase stream continuity and improve connectivity in the upstream direction. Using two modern multispecies fish-passes, this study aims to investigate multiyear abundance of holobiotic potamodromous fish and their seasonal movement patterns in relation with environmental factors. The fish passes were monitored continuously during 5 and 7 years and are located in two Belgian streams: the (19.3m³.s-1) and the Berwinne (1.9m³.s-1). Results revealed the presence of 20 different fish species, 14 species in the Berwinne and 19 species in the occurrence, salmonids and cyprinids species were predominant. A great interspecific and intraspecific variability in capture periodicity and in terms of stimulation by combination of factor environmental was observed. This study highlights the complexity and the omnipresence of holobiotic potamodromous fish movements at different life stages, in medium size river and brings new information on fish passes efficiency and use by these poorly known species. [less ▲]

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See detailArrival of european eel in Belgian Part of the Meuse: who and how are they?
Nzau Matondo, Billy ULg; Benitez, Jean-Philippe ULg; Dierckx, Arnaud ULg et al

in Proceedings of the 10th International Conference on Ecohydraulics (2014, June)

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See detailReport on the eel stock and fishery in Belgium 2013/2014
Belpaire, Claude; Buysse, David; Breine, Jan et al

Report (2014)

This report is written in preparation of the EIFAAC/ICES Working Group on Eel meet-ing at Copenhagen (4–10 September 2013). Extensive information on the eel stock and fishery in Belgium has been presented ... [more ▼]

This report is written in preparation of the EIFAAC/ICES Working Group on Eel meet-ing at Copenhagen (4–10 September 2013). Extensive information on the eel stock and fishery in Belgium has been presented in the previous Belgian country reports (i.e. Belpaire et al., 2006; 2007; 2008; 2009; 2010, 2011, 2012 and 2013), in the Belgian Eel Man-agement Plan (EMP), in the first report submitted in line with Article 9 of the eel Reg-ulation 1100/2007 (Vlietinck et al., 2012). This report should thus be read in conjunction with those documents. [less ▲]

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See detailA bit of quiet between the migrations: the resting life of the European eel during their freshwater growth phase in a small stream
Ovidio, Michaël ULg; Seredynski, Aurore ULg; Philippart, Jean-Claude ULg et al

in Aquatic Ecology (2013), 47

The movements and habitat use of resident yellow eels were studied in a stream stretch having both natural and minimum flow zones. N = 12 individuals (total length 505–802 mm) were surgically tagged with ... [more ▼]

The movements and habitat use of resident yellow eels were studied in a stream stretch having both natural and minimum flow zones. N = 12 individuals (total length 505–802 mm) were surgically tagged with radio transmitters and released at their capture sites. They were located using manual radio receivers during the daytime from 2 to 5 days/ week over periods ranging from 200 to 329 days, for a total of 1,098 positions. Eels showed home ranges ranging from 33 to 341 m (median value, 62 m), displayed strong fidelity to sites and demonstrated a great degree of plasticity in habitat use. Eels were slightly mobile throughout the year, but their movements were season and temperature dependent, with a maximum during the spring (mean water temperature, 12 C) and a minimum in winter (3 C). Stones and roots (utilization rate greater than 50 % of eels for more than 30 % of location days) were significantly the most frequently used habitats. Between the two flow zones, the natural flow was the most occupied, with a significantly higher proportion of resident eels(66.7 % of radio-tagged yellow eels) and longer occupation (81 % of location days) than the minimum flow zone with less suitable habitats. [less ▲]

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See detailSpawning behaviour and mating success in hybrids of silver bream (Blicca bjoerkna L.) and rudd (Scardinius erythrophthalmus L.) in an experimental environment
Nzau Matondo, Billy ULg; Ovidio, Michaël ULg; Philippart, Jean-Claude ULg et al

in Animal Biology (2013), 63

The egg-release, mating, courting and aggressive acts for the spawning behaviour as well as the survival rates after spawning at stages of eyed embryos, viable hatchlings, and larvae to dry food ... [more ▼]

The egg-release, mating, courting and aggressive acts for the spawning behaviour as well as the survival rates after spawning at stages of eyed embryos, viable hatchlings, and larvae to dry food consumption for the mating success were studied in cultured silver bream Blicca bjoerkna × rudd Scardinius erythrophthalmus hybrids at their first sexual maturity. Experiments were conducted in experimental environments simulating natural reproductive conditions of the parental species. Spawning behaviour was analysed over 1 day from 8.00 to 18.00 hours using a remote-controlled video. Mating success was assessed from eggs and hatched embryos collected on the spawning ground. The results showed that these hybrids exhibited all the reproductive behaviours of the parental species with significantly more courtship than mating. Each egg-release act was accompanied by mating behaviour, involving all the experimental males. A surprising aggressive behaviour was observed in one male which attacked all other experimental fish. Successful mating resulted in the presence of fertilized eggs, the production of hatched embryos in experiments, and the survival of larvae at the dry food consumption stage. However, the low viable hatchling rate observed could indicate a very low chance of survival for these hybrids in rivers in which the occurrence of post-F1 individuals may be more possible by backcrossing. [less ▲]

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See detailEvaluation de la qualité biologique des rivières wallonnes sur base des indices biologiques poissons. Support technique aux inventaires 2012.
Rimbaud, Gilles ULg; Ovidio, Michaël ULg; Dierckx, Arnaud ULg et al

Report (2012)

Ce rapport a pour objectif l’évaluation de la qualité biologique des eaux de surface basée sur les indices biologiques « poissons » dans un certain nombre de cours d’eau de Wallonie. Il résulte d’une ... [more ▼]

Ce rapport a pour objectif l’évaluation de la qualité biologique des eaux de surface basée sur les indices biologiques « poissons » dans un certain nombre de cours d’eau de Wallonie. Il résulte d’une convention entre le Service public de Wallonie et l’Université de Liège. [less ▲]

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See detailA comparative study of sexual product quality in F1 hybrids of the bream Abramis brama X the silver bream Blicca bjoerkna
Nzau Matondo, Billy ULg; Ovidio, Michaël ULg; Philippart, Jean-Claude ULg et al

in Fisheries Science (2012), 78

The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured ... [more ▼]

The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured Abramis brama 9 Blicca bjoerkna F1 hybrids and compared with the parental species at their first sexual maturity. Females ovulated under environmental conditions, and their eggs were weighed, counted and measured. Semen of males was macroscopically examined and spermatozoa counted using a hemocytometer. Results revealed that hybridization affected the quality of female and male gametes but with an overlap between hybrids and parents. The gonadosomatic index and fecundity were significantly lower than those of parental species. Egg sizes in hybrids showed a parental effect but to the benefit of hybrids. Semen of hybrids was more diluted which was classified into two groups: the white semen overlapping slightly with parents and the aqueous without any overlap with parents. Overlapped areas between hybrids and parents in term of quality of sexual products could translate that females and males of these hybrids have the biological capacity to produce high quality gametes and thus, a greater chance to produce F2 and backcross generations in rivers. [less ▲]

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