bluuebunny/crossref_metadata_2025_split huggingface dataset:
The spread of myxomatosis in the Netherlands
Authors:   Department of Wildlife Management of the Ministry of Agriculture, Fisheries and Food, The Hague
Published: November 2022

Myxomatosis in the Netherlands was first discovered at Noordwick, west of Leyden, in tame rabbits (September 9, 1953). On 14th September, 1953 the disease was first observed in wild rabbits on the island of Wal-cheren. The disease gradually penetrated the Netherlands from the south (Belgium) and from the east (Germany). At present, there are three large areas where myxomatosis prevails :
1. The dune districts on the sea coast. It should be observed here that so far the disease has not reached the Frisian islands, except Texel, the southernmost of these islands.
2. South of the large rivers, where it prevails in several countinuous areas. 3. In a practically continuous area in the middle of the country, north of the large rivers.
The disease has not reached :
1. A large area in the northern part of the country, namely the provinces of Friesland, Groningen and Drente, and
2. The Frisian islands, except Texel, the southern most of these islands.
It seems that the months of September, October and November provide the most favourable conditions for the disease to spread, as regards the number of new cases within a centre that has already developed, as well as the development of new centres.
No investigations have been carried out in the Netherlands into the question of how the disease has been transmitted. There is no conclusive evidence that the animals have been deliberately infected.
No cases are known of myxomatosis among hares.
Cases have been observed of a new gradual increase in the rabbit population in areas where the disease has prevailed.
Cases have also been observed where the disease prevailed for some months, though later on it disap¬ peared without having exterminated the entire rabbit population. However, in such cases the percentage of survival was low (between 1-5 %).
Experience has shown, however, that in places with a fairly large or a large rabbit population myxomatosis rages violently and often reduces the number of animals considerably within a short time, whereas in shooting grounds with a very moderate or a moderate rabbit population the disease gradually develops and lingers on for a long time. The impression is justified that in these places the percentage of survival is higher. So, as far as infection is concerned, direct contact between the animals could be a very important factor.
Small localities have been found where myxomatosis had not penetrated, though they were situated in infected areas.
There is no conclusive evidence of any change in the behaviour of birds and beast of prey.
Le saturnisme, fléau de la sauvagine en Camargue
Authors: Hoffmann Luc 
Published: November 2022

Lead poisoning of ducks in the Camargue.
The first chapter is a brief summary of the work done abroad on this matter.
The second chapter gives a fist short account of investigations made in the Camargue. It is based on fluoroscopic inspection of 7988 ducks of 3 species in 2 consecutive winters. It is shown that lead-poisoning rate in the Camargue is nearly 3 times higher than that of the whole United-States. Such a rate is propably the highest known until now. Seasonal evolution of Teal lead-poison-ing has its peak in January, dropping down in February and March, while the duck shooting season goes on until the end of March.
The third chapter gives an account of experiments which indicate (but not yet definitely prove) that in muddy areas as in the Camargue, sowing of fine gravel in the marshes may reduce lead-poisoning.
The ecology and management of moose in North America
Authors: Pimlott Douglas h. 
Published: November 2022

During the past decade, in North America, many concepts about moose have changed. Fears that they would be extirpated have been replaced with the knowledge that, when in good habitat, they can withstand heavy hunting pressure.
Many of the past estimates of moose numbers and population trends have been guesses, or have been based on information of a subjective nature. In general, very little is actually known about previous moose numbers and fluctuations.
Aircraft are now being used extensively to census moose. A transect-line survey method is widely used, however, in Ontario, the results obtained by this method are considered to be too variable to be of value. A system of intensive search of 25-square-mile (65-sq.-km.) plots has now been adopted for use in the province. Results of aerial surveys indicate that densities of 1 moose per 1 or 2 square miles (2.6 or 5.2 sq. km.) are not uncommon for large units of range.
The results of studies conducted in British Columbia and Newfoundland have shown that the reproductive rate of moose is quite variable. Three aspects of moose reproduction — breeding and pregnancy rates of yearlings, pregnancy rates of adults, and the occurrence of twins — were found to vary from area to area. There are important differences in the winter food and cover of moose on eastern and western ranges. In the East the key browse species are trees, while in the West the most important species are shrubs (Salix spp.) . Moose on eastern range tend to be rather uniformly distributed in winter, while on western range large concentrations are much more common.
The possible role of factors that limit moose populations is considered by the use of three examples : moose on optimum range, on islands, and at the southern limit of eastern range. Over most of the area of moose range, food shortage, interacting with winter tick infestations, appears to be the primary limiting factor. The inadequacy of the annual harvest is the most pressing problem in the management of moose. Hunting regulations across the continent vary from completely closed seasons to long open seasons for the hunting of animals of any sex or age.
Browsing by moose appears to have the greatest effect on the flora of the secondary succession of the white spruce-balsam fir-white birch associations of the boreal forest formation. White birch is highly palatable to moose at all times of year and under heavy browsing pressure it may be eliminated. Balsam fir is a winter food and is not seriously affected until the carrying capacity of the range is reached. Of the shrubs, Taxus is most heavily utilized and it virtually disappears when heavily browsed.
Données quantitatives sur une biocoénose ouest-africaine : la prairie montagnarde du Nimba (Guinée)
Authors: Lamotte Maxime , Aguesse Pierre , Roy R. 
Published: November 2022

La biocoenose de la prairie montagnarde du Nimba (Guinée) a fait l’objet, depuis 1942, d’analyses quantitatives poursuivies durant toutes les saisons de l’année, par la technique des relevés quantitatifs sur 1 m² et sur 25 m². Il a été possible ainsi de préciser le «spectre zoologique» du peuplement animal, c’est-à-dire la place relative — tant en ce qui concerne le nombre d’individus que leur biomasse — des différents groupes zoologiques non microscopiques. Cette étude fait ressortir l’importance particulière de certains groupes : les Oligochètes, en premier lieu, et aussi des groupes hygrophiles comme les Gastéropodes, les Opilions, les Diplopodes, les Dermaptères, les Blattes et les Batraciens. Au total, la biomasse animale sur 100 m2 est de 1.850 g. de poids frais en moyenne, dont près de 1.000 g. pour les seuls Oligochètes.
Une autre caractéristique de ce peuplement est la pauvreté en espèces (une centaine au total), liée à la rudesse des conditions de vie : alternance d’une longue saison humide et d’une saison sèche très rigoureuse.
L’étude de la stratification de la faune dans son biotope a montré que la répartition des biomasses est très inégale entre les trois strates de la prairie : les animaux endogés dominent très largement (80 % du total de la faune), tandis que ceux de la litière ne forment que 16,6 % et ceux de la strate herbacée 3,4 % du total. Dans la litière, et plus encore dans la strate endogée, les saprophages tiennent de loin le rôle principal.
L’analyse des régimes alimentaires des principales espèces a permis de caractériser le cycle trophique de la biocoenose. Le premier trait de cette structure trophique est l’extrême prépondérance des producteurs primaires — Graminées essentiellement — par rapport aux consommateurs primaires et secondaires : 185 kg (poids frais) par 100 m2 de matière végétale pour 1,35 kg (poids frais) de matière animale. Autrement dit, il y a sous-exploitation du milieu végétal par les animaux, en liaison peut-être avec l’absence de grands Mammifères. Au sein de la biomasse animale, les consommateurs secondaires ne constituent qu’une faible fraction (9 %) du peuplement. Dans la strate endogée, ils ne représentent même que 1 % de la biomasse totale, contre 29 % dans la litière et 41 % dans la strate herbacée.
Relations écologiques des avifaunes sédentaire et migratrice dans une savane sahélienne du bas Sénégal
Authors: Morel Gérard J. , Bourlière François 
Published: November 2022

Monthly censuses were made of an area of 25 hec¬ tares (±62 acres) in the sahelian savannah of the lower Senegal valley, from February 1960 to May 1962. All the birds seen were counted, palearctic and african migrants as well as breeding pairs and nomadic individuals, to estimate the monthly biomasses of the avian consumers.
The average adult weigt, the migratory status, the staple food, the layer at which the birds ordinarily live, and the seasons of reproduction of the 97 species recorded (66 sedentary species and 31 palearctic migrants) are given in table 1. Among the sedentary species, only very few live all the year round in the actual census area, most of them being nomadic.
Table 2 gives, month by month for the three consecutive years, the number of individuals counted, the number of species and the biomasses in grams, both for sedentary birds and for migrants.
Tables 3 to 5 give the same data for the three main trophic categories of our avian population : vegetarian, polyphagous and insectivorous.
Eight months out of twelve, palearctic migrants were present in this area ; for most of that period they form an appreciable part of the total population. The highest densities and the greatest biomasses occur at the same time of the year in african species and in migrants. The maximum population density of african birds reached 4,2 birds per hectare in September 1960 and 8,2 birds
Natalité et mortalité dans une population naturelle d’un passereau tropical, le Lagonosticta senegala
Authors: Morel Marie-Yvonne 
Published: November 2022

The breeding cycle, clutch size and frequency, mortality rate of eggs, nestlings and adults, and general productivity of a wild population of the Senegal fire-finch Lagonosticta senegala, banded at the Ornithological Station of Richard-Toll, Sénégal, were studied during the period 1954 to 1964.
The breeding season lasts for 9 months, from the first half of July to the beginning of April. During the season a single individual adult male has been shown by banding to be capable of breeding four times in succession. Despite the fact that they have been hatched in different months of the breeding season, the young all reach maturity simultaneously, about the beginning of August, and are then ready to breed in their turn.
Both the number of eggs and the number of fledglings produced per pair of breeding adults each year are very high, off-setting the high mortality rate of the population.
Only 45 % of the eggs laid are hatched, and only 28 % of them result in fledged young. The adult death rate has been estimated in two different ways ; by the use of the «composite life table», as defined by Hickey, in the case of males, and by calculating the percentage of banded individuals breeding for the first time out of the total breeding population. Both methods give an average annual adult mortality rate of 70 to 75 %. Despite the fact that a very small percentage of individuals in the population survived to an old age (7 years), the expectation of life of the newly-hatched Senegal Fire-finch is low and the population turnover rapid.
At the nest stage the parasitic weaver Hypochera chalybeata is one of the most important mortality factors among nestlings. Although clutch-size is the same in normal and parasitized nests (3.5 and 3.3), and although the percentage of eggs hatching is the same in both cases, the mortality among nestlings is twice as high (53 %) in parasitized nests as in normal nests (25 %).
Effets de la prédation sur l’évolution des cris des jeunes oiseaux. I.
Authors: Brosset André , Chapuis C. 
Published: November 2022

Based on the premise that the call of a fledgling passerine is difficult to locate by ear, the authors have formulated the hypothesis that these vocalizations evolved to make perception and location difficult for the potential predator. To test this hypothesis various vocalizations (adult song and alarm call, fledgling call) of four different species of birds (english sparrow, lark, blackbird and corn bunting) were played back at the same volume to three carnivorous mammals : a dog, a Tayra and a Red Fox.
In a preliminary series of experiments, a preconditioned dog was subjected to a multiple choice experiment in selecting one sound from the bird’s vocal repertoire emitted simultaneously through a loudspeaker. A second series of experiments was made with a pet Tayra let loose in a wood. This test attempted to establish the distance at which the Tayra shows, through its behavior, perception of the bird’s vocalizations, both adult and/or fledgling. A third series of experiments was held with a non-conditioned Red Fox which was spontaneously attracted by all the vocalizations. Finally, a fourth series was conducted in the presence of a sleeping dog and, separately, a Tayra engaged in play.
The results of these experiments confirmed the validity of the initial hypothesis. When comparing the alarm call to the fledgling call, the latter elicits little reaction from the mammalian predator. In the choice experiment where the bird vocalizations were simultaneously emitted at the same volume, the dog almost invariably selected the adult calls. Even when the dog was asleep and the Tayra playing, both reacted to adult but not to fledgling calls.
As surmised, the different bird calls had a widely different response elliciting power. The Lark’s whole repertoire had a low level of response for the predator tested, while the Blackbird and the Corn Bunting had a high one.
Some experiments tend to demonstrate that the fledgling call may be perceived by the Carnivore, but does nos trigger a predatory response. This is obviously due to some cortical «filtering mechanism» rather than to an inability to perceive certain sound patterns. Further experiments will have to establish the parameters of the fledgling calls which are responsible for the low predator response level.
Comparaison de plusieurs indices de diversité dans l’étude d’un peuplement de Mantes
Authors: Gillon Yves , Pernès J. 
Published: November 2022

The biological diversity of praying Mantids has been analysed to illustrate some classical indices between stability and diversity on the one hand and the numbers of individuals and species on the other.
A good description of the Mantid communities can be reached by using only two parameters : the «⍺», of Fischer for specific richness and the «E» of Margalef for interspecific relations.
Rapports des eaux souterraines avec les sols halomorphes et la végétation en Camargue
Authors: Heurteaux Pierre 
Published: November 2022

La répartition de la végétation des terrains naturels de Camargue est régie par l’interaction d’un ensemble de facteurs écologiques dont les plus apparents sont la salure des sols et la topographie, mais auxquels il faut ajouter la minéralisation et la profondeur des eaux souterraines, les conditions climatiques, la texture, la structure et la teneur en eau des sols.
Les terres les plus basses (moins de 0,50 m au-dessus du niveau de la mer) sont les plus salées, elles sont le domaine des groupements à Salicornes dont les mieux représentées sont, par ordre croissant de résistance au sel et à la sécheresse :
— le groupement à Salicornia fruticosa ;
— le groupement à A. glaucum et S. fruticosa ;
— le groupement à A. glaucum et Sphenopus divaricatus.
Les terres les plus hautes sont moins soumises à l’influence du sel, elles sont occupées par les pelouses.
Les sols sous pelouses ont une texture sablo-limoneuse et une structure grenue. Jusqu’au printemps, la percolation des pluies assure un bon lessivage superficiel et, bien que la teneur en sel de la nappe aquifère soit souvent assez forte, la concentration de la solution du sol dans la rizosphère reste inférieure à la limite fixée pour les sols salins. En été, le milieu devient légèrement salin et fortement xérique.
Les sols des terrains bas sont des sols salins du type Solont-chak. Le maintien à faible profondeur des eaux souterraines entraîne des manifestations d’hydromorphie. La répartition des groupements végétaux dépend de l’intensité des remontées salines et des conditions hydriques régnant dans la rhizosphère. Elles-mêmes dépendent du climat, de la topographie, de la profondeur et de la salure des eaux souterraines.
Le groupement à Salicornia fruticosa est hygrophile. Il occupe le pourtour des marais et les zones déprimées sous lesquelles la nappe aquifère est peu profonde.
Le groupement à Arthrocnemum glaucum et Sphenopus divaricatus occupe les terrains trop secs ou trop salés pour qu’y prospère le Salicornietum fruticosae. Les annuelles du groupement les plus sensibles au sel occupent les micromilieux localement moins salés («touradons» et cœur des touffes d’A. glaucum).
Le groupement à A. glaucum et Salicornia fruticosa apparaît lorsque les conditions écologiques sont intermédiaires.
On a pu établir les gammes des salinités des sols et des eaux souterraines compatibles avec chaque groupement végétal (voir fig. 3).
Quand la teneur en sel s’élève dans la tranche superficielle du sol, la survie des végétaux devient de plus en plus précaire. Pour une teneur en Cl de la terre sèche supérieure à 20 ‰ (conductivité des extraits de pâtes saturées 80 mmhos), seules quelques maigres touffes d’A. glaucum continuent à végéter sur un sol qui se couvre d’efflorescences salines : c’est le domaine de la sansouire. Pour une teneur en Cl de la terre sèche supérieure à 28 ‰ (90 mmhos), toute vie végétale supérieure devient impossible et le sol nu se couvre d’une croûte saline blanchâtre : c’est le domaine du «salant».
Évolution saisonnière de l’avifaune dans une futaie de Chênes en Bourgogne
Authors: Frochot Bernard 
Published: November 2022

A study was made of the phenology of the bird populations of two different and distinct vegetation types, which represent two extreme succession stages resulting from the shelterwood system of management of Quercus pedunculata forests in Burgundy. Bird populations were counted throughout the year along line transects.
The avifauna of old, sub-climax, shelterwood remains remarkably stable throughout the year. About half of the nesting birds are sedentary species, and there are few winter migrants or transients which pass through during the course of spring and autumn migrations.
On the other hand, the bird fauna of young, bush shelterwood is characterised by marked seasonal variations. There are very few sedentary, breeding forms and many species (particularly Thrushes and Finches) are recorded during the course of spring and autumn migrations, as they are generally in other open habitats. The young shelterwood also provides an important area for several winter visitors, such as Reed buntings, Siskins, Blue tits and Great tits.
In both habitats, birds numbers reach their lowest levels in winter, with January the month when the smallest populations are recorded. This corresponds with the availability of food. Traps show an almost total absence of flying insects (that is to say, insects available to birds) from the end of November to the beginning of February, whilst in winter there are none of the berries so abundant in the bushy habitats in autumn. The two habitats support comparable numbers of birds during the breeding season, though in winter many more birds are found in the old shelterwood than in the younger succession stage. The winter visitors to the young shelterwood are too few to make up the numbers lost by the departure of the warblers and other insectivores, which constitute the summer populations. This difference is attributable to the availability of food, which remains higher in the older shelterwoods (hibernating insects, dry fruits) than in the younger succession stages. Many species remain in the older shelterwoods throughout the winter, showing a poly-phagous feeding behaviour which can be considered to reflect their evolution in this type of habitat.
The existence of different plant communities, with different phenologies, in the same forest area helps many species which benefit from the different kinds of food resources provided by such an heterogenous habitat during the course of the year.
Recherches écologiques dans la savane de Lamto (Côte-d’Ivoire) : Données préliminaires sur le peuplement en termites
Authors: Josens G. 
Published: November 2022

Data are given on the distribution and. numbers of termites, their fungus gardens and nests, in the Lamto savannas in the Ivory Coast.
The termite populations at Lamto are dominated by four subterranean Macrotermitinae species : Ancistrotermes cavithorax, Microtermes toumodiensis, Pseudacanthotermes militaris and Odontotermes pauperans and by two foraging, mound-constructing Nasutitermitinae : Trinervitermes geminatus and T. togoensis. The poverty of humivorous species nests constitutes another salient feature of these populations.
The density of termite colonies in Lamto depends on the water content of soils, soil texture and availability of food (cellulose).
Contribution à l’étude éco-éthologique du Grand murin (Myotis myotis)
Authors: Schierer A. , Mast J.-Cl. , Hess R. 
Published: November 2022

Les auteurs rapportent des observations effectuées dans une colonie de mise bas du Grand Murin (Myotis myotis). Le gîte est situé dans les combles d’un édifice public. L’effectif de la colonie dépasse vers la mi-juin 2 000 sujets. Le baguage a porté, avant la saison d’observation, sur 1 074 sujets. Une technique est mise au point pour la réalisation d’opérations de baguage d’une certaine envergure.
Les facteurs climatiques, extérieurs et intérieurs à la colonie, sont enregistrés à titre comparatif et les auteurs tentent d’établir une corrélation entre les variations de certains paramètres climatiques et le comportement des Murins tout au long de la saison estivale.
Le régime alimentaire est évoqué ; il semble que les proies préférentielles (Coléoptères) dépassent la taille de 18 mm. Un cas de canitie et des perforations du patagium sont décrits. Le rejet de jeunes par leur mère semble avoir été inhabituellement élevé pendant l’année 1970 qui peut être considérée comme pluvieuse sur le plan local.