Martin pêcheur d'Europe, Alcedo atthis; ; Libois, Roland ![]() in Jacob, Jean Paul; Dehem, Christophe; Burnel, André (Eds.) et al Atlas des oiseaux nicheurs de Wallonie 2001/ 2007 (2010) The kingfisher is widespread in Wallonia but is missing locally in middle Belgium and in higher Ardenne. The field prospection for the atlas took place in a favorable climatic context; the current ... [more ▼] The kingfisher is widespread in Wallonia but is missing locally in middle Belgium and in higher Ardenne. The field prospection for the atlas took place in a favorable climatic context; the current population, estimated at 450 650 pairs, reflects probably the saturation of the habitat. The highest densities are found along large rivers, with important fishing ressources and numerous nesting sites (Lesse, Ourthe, Semois, Viroin). The limiting fator seems to be the lack of nesting sites. [less ▲] Detailed reference viewed: 37 (2 ULg) Impact assessment of breeding European kingfisher (Alcedo atthis) on prey fish; Libois, Roland ![]() in Cowx, Ian (Ed.) Interaction between fish and birds: implications for management (abstracts) (2001, April) Detailed reference viewed: 4 (0 ULg) Martin pêcheur d'Europe, Alcedo atthisLibois, Roland ; in Rocamora, Gérard; Yeatman Berthelot, Dosithée (Eds.) Oiseaux menacés et à surveiller en France. Liste rouge (1999) Detailed reference viewed: 6 (1 ULg) State of the Biodiversity in the Walloon region; Dufrêne, Marc ![]() in First National Report of Belgium to the Convention on Biological Diversity. (1998) Situation actuelle de la loutre, Lutra lutra, en Belgique et problématique de sa conservationLibois, Roland ; in Cahiers d'Ethologie (1995), 15(2-3-4), 157-168 Widespread all over the country till the end of the last century, the otter has rapidly declined. In 1973 when hunting was definitely closed, the otter was already threatened and restricted to a few ... [more ▼] Widespread all over the country till the end of the last century, the otter has rapidly declined. In 1973 when hunting was definitely closed, the otter was already threatened and restricted to a few localities. In 1889, the Belgian Ministry of agriculture decided to pay bounties for otters, a system which was cancelled only in 1963. Game statistics of the past century allow the annual otter bag to evaluated as roughly 25 % of the standing population. As it is the case in other European industrialised countries, freshwater habitat loss and water pollution lead to a considerable decrease of the river carrying capacity. Almost all the rivers flowing in the Northern part of Belgium are now lifeless or at least in a very bad condition. South of the river Meuse, some accidental pollutions are regularly reported (chloring in the river Ourthe in 1993; chloracetic acid in the Sûre in 1990...) and the level of organic pollution rises from year to year. Moreover, the tourism (angling, camp sites, kayak) nare more and more intensive leading to major disturbances, particularly during the summer months. Finally, the Ministery of equipment is developing a policy of big hydraulic works (dams, embankments, dredging...) along the river Ourthe, one of the last to be occupied by a few otters. [less ▲] Detailed reference viewed: 23 (2 ULg) Martin pêcheur d'Europe, Alcedo atthisLibois, Roland ; in Yeatman-Berthelot, Dosithée; Jarry, Guy (Eds.) Nouvel atlas des oiseaux nicheurs de France 1985-1989 (1994) Detailed reference viewed: 12 (3 ULg) Le martin pêcheur: un ambassadeur haut en couleur pour un milieu menacéLibois, Roland ; Learning material (1991) Detailed reference viewed: 1 (0 ULg) Martin pêcheur d'Europe, Alcedo atthisLibois, Roland ; in Yeatman-Berthelot, Dosithée; Jarry, Guy (Eds.) Atlas des oiseaux de France en hiver (1991) Detailed reference viewed: 6 (1 ULg) Expansion et régression: deux mots clés de la dynamique des populations du martin pêcheur (Alcedo atthis)Libois, Roland ; in Aves (1989), 26(n° spécial "Actes...."), 93-101 Annual censuses of nest kingfishers are performed since 1973 in the valley of the river Lesse, a tributary of the river Meuse (Belgium). The authors document sharp population fluctuations. It appears that ... [more ▼] Annual censuses of nest kingfishers are performed since 1973 in the valley of the river Lesse, a tributary of the river Meuse (Belgium). The authors document sharp population fluctuations. It appears that these are mainly due to the weather conditions prevailing at key-periods. Hard winters reduce the numbers, sometimes to a low level, whereas heavy late-spring or early- summer rains involve a bad reproduiction rate (namely through clutch losses following flooding). Hence, the recovery of the nesting population is weakened. In comparison, other factors such as predation, seem to have only a limitid effect. In other respects, the noxious consequences of permanent disturbances are illistrated in the that part of river Lesse where kayak is practised on a large commercial scale. [less ▲] Detailed reference viewed: 7 (1 ULg) Eléments pour l'identification des restes crâniens des poissons dulçaquicoles de Belgique et du Nord de la France. 2. CypriniformesLibois, Roland ; in Fiches d'Ostéologie Animale pour l'Archéologie. Série A, Poissons (1988), 4 Outline drawings of the most typical skull bones of 23 Cypriniformes species (dentary, maxillary, pharyngeal bone) are presented. The main distinctive morphological features are summarized into ... [more ▼] Outline drawings of the most typical skull bones of 23 Cypriniformes species (dentary, maxillary, pharyngeal bone) are presented. The main distinctive morphological features are summarized into identification keys. Biometrical relationships also computed for eigth common species (Gudgeon, Bleak, Rudd, Roach, Common bream, Carp, Tench and the Stone loach). [less ▲] Detailed reference viewed: 50 (4 ULg) Eléments pour l'identification des restes crâniens des poissons dulçaquicoles de Belgique et du Nord de la France. 1. Anguilliformes, Gastérosteiformes, Cyprinodontiformes et PerciformesLibois, Roland ; ; in Fiches d'Ostéologie Animale pour l'Archéologie. Série A, Poissons (1987), 3 Ontline drawings of some fish bones are presented. These bones were selected since their shape is so typical that it allows the unambiguous identification of a definite species. Moreover, the authors did ... [more ▼] Ontline drawings of some fish bones are presented. These bones were selected since their shape is so typical that it allows the unambiguous identification of a definite species. Moreover, the authors did compute some regression lines between the total length of some fish species and the length of thier typical bones. Twelve such relationships were calculted for eel and one for the three spined stickleback, the perch and the bullhead. All are highly significant [less ▲] Detailed reference viewed: 42 (4 ULg) Le régime de la loutre (Lutra lutra) en Bretagne intérieureLibois, Roland ; ; in Revue d'écologie (Terre et Vie) (1987), 42 Fifty six otter spraints were collected along three oligotrophic streams of Central Brittany, from 1982 to 1985. Pry items were identified, enumerated, and their size estimated, using the same criteria as ... [more ▼] Fifty six otter spraints were collected along three oligotrophic streams of Central Brittany, from 1982 to 1985. Pry items were identified, enumerated, and their size estimated, using the same criteria as those previousely used by Hallet (1977-1985) in her study of the diet of the Kingfisher (Alcedo atthis). Among the 251 prey items belonging to 11 taxa, small fish species such as the bullhead (Cottus gobio) and the minnow (Phoxinus phoxinus) were the most abundant. From the trophic point of view, however, their importance was rather negligible, since their biomass made up 10 % only of the overall biomass ingested. Large prey, such as trout (Salmo trutta), birds and mammals, made up the bulk of the otter diet in this area. [less ▲] Detailed reference viewed: 25 (2 ULg) The Unionid mussels (Mollusca, Bivalvia) of the Belgian upper river Meuse: an assessment of the impact of hydraulic works on the river water self-purificationLibois, Roland ; in Biological Conservation (1987), 42 In september 1983, the nine weirs regulating the flow of the river Meuse between Givet (France) and Namur (Belgium) were kept fully open for technical purposes. The water level therefore dropped, allowing ... [more ▼] In september 1983, the nine weirs regulating the flow of the river Meuse between Givet (France) and Namur (Belgium) were kept fully open for technical purposes. The water level therefore dropped, allowing the sampling of benthic organisms and the mapping of the different kinds of banks. For each bank type, the density of unionids mussels was measured. Silt and fine gravel bottoms are the preferred habitats of these mussels. In these natural habitats, the mean biomass is estimated at more than 1.8 tonnes/ha. In pebbles this value is near 1 tonne/ha whereas in the stony blocks and on rocky bars it falls to 165 kg/ha. Man made banks are poor biotopes: 297 kg mussels/ha on old stoneworks and only 65 kg/ha on recent ones. When the filtration rate is considered, is can be shown that, at the time this study was under taken, the unionid mussels living on the Meuse banks filtered more than 300 litres water/sec. This rate will drop to 27 litres/sec within only a few years if the designed hydraulic works are carried out. This study emphasises the negative effects of these works on the self-purification capacity of the river. [less ▲] Detailed reference viewed: 11 (1 ULg) |
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