Revue d Ecologie

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— General map of North Algeria with the location of the cedar forests. In the Tellien Atlas from West to East: Ouarsenis area (Theniet El Had), Chréa (studied in this paper), Djurdjura (Tikjda and Tala Guilef), and Babors. In the Saharan Atlas: Hodna area (Boutaleb) and Aures area (Belezma, S’gag, Chelia, and Ouled Yacoub). 
— Mean radial growth (mm) of 30 trees from the three sites during the 22 years studied as obtained from wood cores. Reference is the site located on the north side and not infested by the caterpillars; and Attacked 1 and Attacked 2 , are the two sites located on the south side and infested by the caterpillars. 
— Relative mean growth from the same series, obtained by dividing each radial growth rate by the mean radial growth rate of the corresponding site. The infestation period (observed defoliation) is added at the bottom of the figure. 
— Comparison of the calculated radial growth losses for the two attacked sites A1 and A2. The calculated damage period for each site have been added at the bottom of the figure. 
Cedar tree is a mountain forest species that occurs naturally in the Maghreb region. This study describes the consequences of a strong attack of Thaumetopoea pityocampa Schiff. on century-old cedars in Chréa National Park, 50 km southwest of Algiers. Period of damage was assessed by nest census. After two consecutive defoliation events, maximum reduction in growth rate was recorded one year after the first defoliation. Up to 50 % of growth lost were calculated for a complete defoliation. A reduction in growth rate in subsequent years was lower due to trees undergoing recovery growth. These results could contribute to improved management of insect infestations and the protection of cedar plantations, and raise questions about the potential increase of insect attacks with climate change.
 
The national nature reserve of Saint-Brieuc Bay, located in the north of Brittany, is a site of international importance for the wintering of the Black-bellied Brent goose Branta bernicla bernicla although its preferred food, eelgrass, is completely absent. Local monitoring points out that the green seaweeds Ulva armocicana represents 90% of the food eaten by the Brent geese. These algae are responsible for the spectacular green tides which greatly impact this bay each summer. The 400 odd tons consumed each winter by the Brent geese are insufficient to curb this phenomenon. However, the resorption policy of the nitrogenized surpluses arriving in the bay in order to fight against the aestival green tides could, in the long term, reduce this food resource and force geese to find a Substitution food which, locally, could be a grass growing on salt-marshes (Puccinellia maritima) or winter cereals growing in arable lands bordering the bay. To avoid possible crop, the national nature reserve could have to increase the surface of Puccinellia maritima meadows by mowing or by converting to pasture on the climacic areas with Halimione portulacoides as is the practice on the Atlantic coast, in Aiguillon Bay. This will have to be done with caution, the areas with sea-purslanes being important feeding grounds for young fish during the high tides. It is quite singular to see that, in this bay, a wintering area of international interest for a water bird developed thanks to serious environmental perturbation and that this ornithological interest could be disrupted by current curative policies of water quality restoration, should no compensatory measures come to balance for the hoped reduction of the green tide.
 
-map of the study area and location of the 10 sites. a = BP1, b = Ba1, c = BP2, d = BnP, e = Ba2, f = Ba3, g = Bsf1, h = Bsf2, k = chm2, m = chm1.
— relationship between Tolerance index (dolédec et al. 2000) and ellenberg's Light index with the first axis of correspondence analysis (ca). equations of regression lines and determination coefficients are indicated. codes for the 10 study sites as in Tab. i.  
(Left). — Projection of passive variables along axis 1 of ca: sites (in boxes), soil types (underlined), percent occupancy by species groups, average ellenberg indices, average grime strategies and Tolerance index (higher values in bold, lower values in italics, see text for more details). figure 4 (Right). — Projection of the 79 plant species along axis 1 of ca. species codes and letter types as in Tab. ii.  
— relationship between percent occupancy by ericaceous vegetation and plant species richness of unit samples, in 6 oak-free heath sites. codes for sites as in fig. 1. equation of regression line and determination coefficient are indicated.  
Our aim was to ascertain whether changes in plant species richness and other vegetation features occur in heathland dominated by Erica scoparia L. (besom heath) through the impact of cattle grazing and oak colonization. Our study took place in the Brenne Regional Natural Park (center of France) where this cricaceous species, locally called 'brande', is now considered of patrimonial interest and protected at regional and European level. We selected 10 sites in a private property, covering I wide range of ecological conditions (shallow and deep soils, grazed and non-grazed besom heath, pure and oak-colonized besom heath). Vegetation (percent occupancy of plant species) wits sampled in May-June 2006 (105 samples, 1m2) each) and the impact of shrub and tree vegetation on plant biodiversity was assessed by correspondence analysis (CA) and total and partial Mantel tests (Monte-Carlo procedure). An environmental gradient of decreasing light incidence from grazed heath to old heath to oak-wood was depicted, along which a number of ecological, morphological and physiological plant traits (growth habits, Ellenberg values, Grime strategies, Tolerance Index of the plant community) were observed to vary. Species richness decreases when cricaceous or, although to a lesser extent, oak cover increases and it increases under low to moderate cattle grazing. Consequences for the sustainable management of 'brande' are discussed.
 
The breeding numbers of the Gory's Shearwaters Calonectris diomedea of Selvagem Grande (30 degrees 09' N, 15 degrees 52' W) have shown important variations during the last three decades, decreasing from about 100,000 birds at the beginning of the seventies to 5,000 only in 1977 following depredations, and increasing regularly since then to reach nowadays about 30,000. The mean age at first breeding is 8.9 years. Every year, 11.8 % of the breeders temporarily stop breeding, these sabbatical leaves lasting 1.7 years on average and 7 years at most. 56.6 % of the eggs laid produce fledglings, with significant variations between years. The mean annual survival rate of the adults is comparatively low, 92.7 %, higher for females (93.5 %) than for males (91.9 %) and varying significantly between years (min.: 84.1 %, max.: 98.0 %). The survival rate of the immatures between fledging and first breeding is 32.8 % at least. Selvagem Grande population, which numbered an important proportion of young inexperienced birds at the beginning of the eighties, following the depredations of the seventies, has gained age and experience during the eighties and the nineties. But the relatively low annual survival rate of the adults, which is probably linked to the development of new fishing methods, is an alarming sign for the future of the population of Gory's Shearwaters, notwithstanding the conservation actions engaged in the breeding localities.
 
The root uptake of Caesium (134Cs) and its subsequent distribution into the shoots, flowers and leaves, as well as the direct deposition of 134Cs on these parts of the plant, were studied in pot experiments, using three tobacco plant varieties (McNair, Kaba Koulac and Katerinis) that are widely cultivated in Greece. The vertical migration of 134Cs into the soil and the quantity of this element contained in the smoke of burning radio-polluted leaves were also studied. For the root uptake of 134Cs, a significant varietal difference was observed, both in calculated Transfer Factor (TF) and in distribution of 134Cs in the different plant parts. A variety dependent difference in 134Cs content was also measured for foliar uptake (direct deposition). It was observed that the main quantity of 134Cs was absorbed or intercepted by the lower leaves of the plants, compared to the quantity absorbed or intercepted by the other plant parts (sterns, upper leaves and flowers). During the two-month period of tobacco cultivation, the wet-deposed 134Cs was contained in the upper five centimeters of soil, while no radionuclide migration was detected in dry deposition. Finally, the amount of 134Cs detected in the smoke was measured to be less than 1% of the total amount in the ashes of the leaves.
 
An Analytical approach was applied to gilthead seabream Sparus aurata stock evaluation in Mellah lagoon (North-eastern Algeria). Its temporal changes were followed during the period 1999-2003. Individual sea-breams 17-61 cm long were landed. This species recruits when one year old and the gears used (enclosures, gillnets) mainly captured fish 24 to 52 cm long. The coefficients of mortality due to fishing (F) estimated by the analysis of cohorts varied little according to the size of the fish. With an average of 0.09, the values of F remained unchanged from one year to the next and indicated that the stock was little fished. This is confirmed by the low value of the exploitation rate (E = 0.28). The analysis of the 1999-2003 pseudo-cohort gave annual mean values of recruitment, total abundance and total biomass of 113,617 fingerlings, 1.57 million individuals and 66.7 tons, respectively. Taking account of a stable fishing effort, the decrease in yield between 1999 and 2003 shown by the fishing statistics may have been due to a collapse of recruitment. Indeed recruitment was divided by 5.5 between 1999 and 2003, and generated a fall of 81.8% of the biomass available during this period. These results are discussed by taking into account the changes in connection between the lagoon and the sea.
 
Searching for bioindicators easy to use but integrating the influence of environmental factors, in order to help understanding the functioning of different sites on a reef flat, we chose to study the growth of transplants of the hermatypic Scleractinian Acropora muricata. We asked if the growth of transplants of this sensitive coral could constitute an interesting bioindicator. Are rapid and simple measures of the growth of the transplants, over a relatively short period (between 6 months and 1 year), able to express significant differences among different biotopes? In our study, after one year, the growth of transplants results in a slender and open form on a dystrophic reef flat, in a balanced form in an oligotrophic reef flat non subject to a high level of predation, and in a stocky form showing numerous points of adaptative reiteration due to traumatisms on a reef flat subject to a strong swell and a high level of predation. The easy observation of the transplants allows to demonstrate the pressure of predation on living coral colonies, a phenomenon difficult to observe on large branching colonies. The bioerosion which is fundamentally opposed to calcification appears to be, in the case of the external macroerosion by the fish Scaridae, a phenomenon that could secondarily stimulate the calcification. We estimate that the growth of transplants of Acropora muricata can constitute a good bioindicator of the effects of abiotic and biotic factors on sensitive Scleractininians.
 
-Devenir des 59 jeunes Phoques veaux-marins nés entre 1992 et 2001 en baie de Somme.
The most important French Harbour Seal (Phoca vitulina) colony occurs in the Somme estuary, on the eastern French Channel coast, in northern France (max. 76 ind. in 2001). This colony has increased in number for at least ten years and currently produces more than half of the pups born along the French coast. The estuary is exposed to strong human pressure, with mass summer tourism and recreational activities inducing habitat reduction and disturbances. To study the interactions between Harbour Seals and human activities in this area, a conservation and study programme was set up in 1990 by the association Picardie Nature. This permitted the observation and follow up of reproduction and pups born within the estuary. From 1992 to 2001, 59 pups were studied. During this period, 52% of pups were naturally weaned, 32% stranded alive and 16% stranded dead. Despite births being regular temporally and increasing, pup production stayed low (12% ± 0.06), notably when compared to other French Harbour Seal colonies. Strandings accounted for up to 52.9% of pups produced in a year. This phenomenon - combining low pup production and precocious strandings relatively important during the summer period - leads to two hypotheses. The absence of high tide haul out sites in saltmarsh areas, provoked by a massive utilization of upstream parts of the estuary by recreational activities, potentially reduces mother-pup's preferential habitat, so prevents births and good pup production. In addition, recreational activities and the development of tourism seems also to prevent the efficiency of pup weaning with recurrent disturbances in summer. This shows that this peripheral group is highly vulnerable despite the designation of the estuary as a Nature Reserve in 1994. The implementation of specific management strategies of the Habitat Directive should consider this phenomenon.
 
From 1994 to 1996, an actual and retrospective inquest on pastoral practices and Alpine Chamois (Rupicapra r. rupicapra) home ranges was performed in Vanoise National Park, Écrins National Park and in the Bauges Game Reserve (France), to investigate the patterns of inter specific cohabitation between livestock and wild ungulates. Statistical treatments performed on a sanitary data base, recording the results of parasitological examinations performed on 307 Chamois, permitted an estimation of parasite diversity in ten groups of chamois populations. Looking for the influence of environmental factors on diversity indices, we revealed significant species-area relationships. Whereas no correlation was found between diversity indices and the total surface of Chamois home range, H' (Shannon & Weaver) and N1 (Hill) were significantly correlated with the surface of spring home ranges of Chamois and with the surface grazed by livestock within spring preferential ranges. Moreover, a significant correlation between species richness (S) and the surface grazed by livestock in chamois summer preferential home ranges is noted. These results suggest an influence of cattle breeding on diversity fluctuations in helminth communities of Rupicaprinae.
 
This paper is an attempt to describe the impact of the accidental introduction of Alburnus albumus (Linnaeus, 1759), an exotic cyprinid fish, on the autochthonous spccics Barbus setivimensis (Valcncicnncs, 1842) in Keddara dam through monthly sampling during six years, from June 2006 to August 2011. Variance analysis allows concluding to a significant variation during the period of study. Tuckcy's test contrasts the means for 2006 and 2007 to those of the others years. Captures of Barbus setivimensis clcarly decreased, whereas the bleak increased, particularly during the reproduction period. The reduction in Barbus setivimensis numbers cannot be related to the water physico-chemical quality in Keddara dam. The succcss of the invasion of Alburnus alburnus is conditioned by the favourable characteristics of the habitat. We can conclude that there arc a strong competition/predation effect especially for the trophic resources between the two species.
 
— Position géographique des stations d’études dans la région de Djanet (Algérie). 
— Abondance relative (AR %) et biomasse ( %) saisonnières des diverses catégories d’espèces-proies entrant dans le régime alimentaire de la Chouette d’Athéna dans la région de Djanet (Algérie). 
— Variation saisonnière des indices de diversité de Shannon-Weaver, diversité maximale et équitabilité des espèces consommées par la Chevêche d’Athéna en région de Djanet (Algérie). 
From the autumn 2007 to the spring 2008 we studied the diet of the Little Owl Athene noctua in the area ot Ujanet, situated in the extreme soum-fcast of Algeria. The analysis of 128 pellets enabled us to identify 80 species belonging to 6 classes, 12 orders and 32 families, preyed upon by this raptor. Considering the number of preys, insects (relative abundance, AR = 70.1 %) were dominant, followed by rodents (AR = 17.1 %) ; the most selected ones were Mesostena angustata (AR = 18.4 %) and Brachytrypes megacephalus (AR = 17.4 %). Insects dominated whatever the season (AR = 47 % in autumn, 79 % in winter, 63.6 % in spring). In terms of biomass, rodents were dominant with 9 species, two of them being new for the area. The Little Owl exihibit a diversified diet (E = 0.7) in this Algerian area of Central Sahara.
 
The analysis of the structure and dynamics of an invasive population of the Largemouth Bass (Micropterus salmoides Lacépède, 1802) in a Mediterranean wetland was the main goal of this study. Demographic potentialities were described by means of the Von Bertalanffy parameters, the latter obtained using length-at-age data. The mean values of the observed four age classes (recognized by the scale reading) were analysed by the Gulland & Holt analytical method, in order to calculate the curvature parameter (k = 0.49) and the asymptotic length (L∞ = 31). The Von Bertalanffy parameters were not considered to be affected by sexual dimorphism since no between-sexes differences were found in size and population structure. Besides the two previous parameters, we computed longevity of 5 years, with only a limited number of Largemouth Bass reaching this age (due to a high fishing mortality rate). Structure and dynamics of this population seem to reveal its stability and spreading potential, as an expression of the favourable ecological conditions encountered in the study area. Growth parameters reflect the acclimation capability of M. salmoides in a non-native habitat and show the ecological plasticity of this species, capable of colonizing many temperate and warm habitats worldwide, Mediterranean wetlands included.
 
Following a tri-national agreement in March 1993, an area of about 58 000 km2 was delimited for an International Marine Sanctuary in the liguro-provencal basin. A visual line transect survey has been designed to estimate the abundance of the Striped Dolphin (Stenella coeruleoalba) during the summer of 1996 (16.VII-9.VIII). The platform is a 12 meters motorsailer, with a 6 knots cruising speed. Four dedicated observers were in duty. Positions have been measured with reticulated binoculars. The survey track is a serie of 8 legs in saw-tooth pattern totaling an effective effort of 755 nautical milles. A passing mode has been selected for the survey to enable the study of the animal's response to the platform. The data analysis has been performed with distance 2.1 software, assuming the detection probability on the line was unity. 144 sightings were obtained in effort during the survey, including 70 primary detections of Striped Dolphins. A density estimate of 0.56 Striped Dolphins per km2 (CV = 16,4 %) is obtained. This figure is in good agreement with previous results and confirms that the liguro-provencal basin is an area of major importance for the species in the Western Mediterranean. This study opens the possibility of monitoring the abundance in the sanctuary with annual small boat samplings, in addition to the implementation of large scale surveys using 'state of the art' methodology.
 
A qualitative study of the diet of C. barbarus (Costa, 1836) was conducted according to the classic method of analysis of feces. It was supplemented by a quantitative estimation of the amount of ingested plants by the so-called "window method". On the basis of it, an attraction index was calculated for every plant species from the proportion of leaf surfaces ingested by each individual. It turns out that this index is not systematically related to the covering index of the plants present in the biotope, and thus the most eaten plants are not always the most attractive ones. The species Plantago serraria L., Crepis vesicaria L. and Vulpia myuros Gruel. are the most attractive for Calliptamus barbarus, and are characterized by an attraction index over 100.
 
Investigations were carried out among residents in southern Réunion Island to evaluate an eventual effect on Nephila inaurata inaurata populations of the intense Chikungunya vector control during the years 2006 and 2007, a chemical control which targeted the mosquito Aedes albopictus. Surveys indicated a very significant reduction of N. i. inaurata density in areas subjected to the Chikungunya vector control comparatively to those without this vector control. Possible modes of contamination by the insecticide are discussed in relation to the vector control protocol and the active substance used for this control.
 
— Sample sites within the Seybouse watershed. Black dots are sites where C. exul was observed. 
shows the daily counts of adults during the 2010 and 2011 flight periods. The total flight period lasted approximately three months in both years, beginning on early May (05.V and 01.V, respectively) and ending on late July (21.VII and 24.VII, respectively). In the first year, the population showed two peaks of presence of adults, with the first on mid-May and the second on early June (Fig. 2). The in-between depression corresponded approximately to the period of the temporary presence of a large and noisy water pump used for irrigation at the edge of the channel, and the latter was thought to be a source of disturbance promoting the dispersal of individuals out of the sampled section. In 2011 only one peak was recorded, on mid-May, and the number of adults severely decreased at the beginning of June. Heavy rains recorded at the end of May, accompanied by repetitive discharge of dam water, were thought to have induced an early collapse of the adult population. I was sure that no adult remained at the site studied or at its vicinity at the end of July 2011 (24 th-31 st ) so that the observation of few tenerals and immatures never exceeding 5 individuals from 2 to 16 September 2011 was rather surprising and will be discussed below. The reproductive season of the species started on 16.V.2010 and 12.V.2011, giving a maturation period of 11-12 days. 
-Daily counts of adult individuals of Calopteryx exul in 2010 and 2011. Open bars = females; black bars = males.
— Biplot of Principal Component Analysis performed for habitat features, species abundance and sample sites. Site codes are presented in table I. " Max exul " and " max haem. " refer to the maximum number of adult individuals recorded for Calopteryx exul and C. haemorrhoidalis respectively. 
Calopteryx exul Selys, 1853 is an endangered endemic Odonata species restricted to the Maghreb that shows an increasing concern about its conservation status, due to substantial habitat loss. A study dealing with its flight period, the apparent sex-ratio of imagoes and adult habitat preferences was carried out in the Seybouse basin, northeastern Algeria, during two years. The flight period of the species begun on early May and ended on late July, showing a peak around late May / early June. Either a small second generation or delayed emergences was responsible of the record of scarce tenerals and immatures in early September. Additional larval investigations are needed to elucidate the origin of such late emergences. The maturation period was estimated to extend over 11-12 days. The apparent daily sex-ratio in the adult population present on site was mostly biased with 65 to 67% of females. Additional work addressing sex-ratio at emergence is needed to understand this disequilibrium. Multivariate analysis showed that adults of C. exul prefer relatively fast flowing shallow water when compared to its congeneric C. haemorrhoidalis (Vander Linden, 1825), which was mainly observed at deeper, slower and very shaded running waters with dense banks vegetation. The population of C. exul dealt with in this study is currently the largest one reported so far in the Maghreb. Data on adult phenology and habitat preferences will allow future investigations about the present distribution of the species in Algeria and the whole Maghreb.
 
In this work we carried out one of the first extensive field researches on the reproductive site selection and the reproductive success of a wide metapopulation of Italian Tree Frog (Hyla intermedia), an Italian endemism that only recently has been recognized as different from the better known European Tree Frog (Hyla arborea). An accurate census of all the water sites in the territory of the "Baraggia del Piano Rosa" Natural Reserve (Piedmont, Northern Italy) was conducted in the years 1997 and 1998. This particular environment (anthropogenic sub-montane continental heathland) is characterized by a heterogeneous open landscape and many small seasonal wet zones. We observed a good overall presence of tree frogs and their spatial distribution showed a typical metapopulation structure. Data collected on many environmental parameters characterizing the sites and their surroundings were investigated using Discriminant Function Analysis, in function of the presence and reproductive use by H. intermedia and their role in a "source-sink" metapopulation model. These analyses show that tree frogs avoided almost completely deep, shadowed, permanent water sites, suggesting the strong thermophily of the species. Generic disturbance caused by human activities resulted to influence negatively H. intermedia reproduction, but not their presence. The preference for intermediate and advanced phases in the hydroseral succession was also evidenced. Our study indicated the importance of some "source" sites characterized by a trade-off between water temperature and stability for the successful completion of the critical larval stage.
 
-Précipitations totales annuelles (mm/an) enregistrées entre 1906 et 2011 à la station météorologique de tinja (gouvernorat de Bizerte ; Becom et al., 1995 ; anPe, 2004-2009). La ligne discontinue représente la moyenne annuelle calculée sur 40 ans (1960-1999). Les années 1959-60 à 1962-63 sont manquantes.
-Aménagements hydrauliques sur l'oued Joumine (1948-2002) : canalisation de l'oued (1948, 1963, 1982 ; stevenson et al., 1993) et aménagements de digues et de banquettes (2008).
-Plans 1 x 2 des analyses factorielles des correspondances, réalisés sur (a) l'ensemble des 99 relevés phytosociologiques effectués en 2008 sur le marais de Joumine, et (B) sur 93 relevés, excluant les 6 relevés réalisés dans des milieux temporaires d'eau douce. La signification des abréviations des noms d'espèces est donnée en annexe 1.
-Répartition, selon une classification hiérarchique ascendante, des espèces des 93 relevés phytosociologiques effectués en 2008 sur le marais de Joumine (les 6 relevés exclus de l'analyse sont ceux des milieux temporaires d'eau douce).
The vegetation of Jouminc Marsh (National Park of lehkeul, Tunisia) has been studied from 2005 to 2011 with the aims: (1) to characterize the present-day status of the marsh vegetation based on plant inventories and phytosociological surveys, (2) to identify the influence of intcrannual hydrolo-gical changes on the plant distribution, and (3) to reconstruct, on the basis of previous works, the vegetation dynamics over the past 86 years (1925-2011). Results reveal the regression and sometimes the local extinction of the plants of temporary freshwater habitats, and their replacement by halophilous, cultivation-tolerant, footpath and grazing-tolerant species. Such changes express the artificialisation of the marsh. The mid-term dynamics of Jouminc Marsh (1925-2011) is characterized by four periods: (I) before the first hydrological developments realized on the Jouminc Wady in 1948, the marsh was dominated by the helophytic formation of Bolboschoenus glaucus and Schoenoplecius litoralis; (2) between 1948 and the putting into service of the Jouminc Dam in 1982/83, the helophytic vegetation remained dominant; (3) between 1982-1983 and the summer 2002, because of an inappropriate management of the reservoir (without freshwater release), the salinity of the marsh has considerably increased, triggering the decline of the hydrophilous vegetation and the expansion of salt scrubs of Sarcocornia fruticosa; (4) finally, since autumn 2002, occasional releases of freshwater from the Jouminc reservoir and the realization of new hydrological developments on the Jouminc ditch lead to the inundation and washing of the marsh. These changes have induced the partial replacement of the salt scrubs by renewed helophytic herbaceous formations. This study reveals the significance of the ratio "hydro-hygrophilous plants/halophilous plants" as an indicator of the health of coastal wetlands. This ratio, as a simple tool for helping the management, may be used at the scale of the entire system lake-marsh of Ichkcul.
 
Experiments in a flight cage and observations in the field were carried out in North-western Madagascar to study the feeding preference of Rousettus madagascariensis (Family Pteropodidae) between an introduced fruit, jujube (Ziziphus jujuba, Family Rhamnaceae) and an endemic fig (Ficus sakalavarum, Family Moraceae) during the dry season, in May and June 2009. We also investigated quantitative aspects of seed dispersion by R. madagascariensis. Juvenile bats (13) fed intensively on F. sakalavarum, while adults (20) ate both fruit species but with a pronounced preference for unripe Z. jujube fruits. This preference for unripe (immature) fruit, the seeds of which are too large to swallow, suggested that R. madagascariensis does not affect seed dispersal in Z. jujuba. Almost half of the ingested seeds of F. sakalavarum were found in faeces of R. madagascariensis voided during the night in the flight cage, and the remainder was found in regurgitated 'ejecta' pellets. Rousettus madagascariensis is thought to be an effective seed disperser off; sakalavarum, particularly for isolated trees or those in forest fragments where other frugivores are rare.
 
Population structure and annual reproduction cycle of the De Balsac's mouse (Heimyscus fumosus) were studied in a wild population of south-western Gabon. The reproductive status of the mice was investigated at autopsy, and age of each animal was estimated by tooth wear patterns and body weight. Sex-ratio was equilibrated whatever the season and the age-class. Females tended to reach sexual maturity more slowly than males. However, the average age at puberty differed between individuals of the same sex. A wide range of tooth-wear-classes and weight-classes were present in most months of the year, and sexually active individuals of both sexes were captured in most months. However pregnant or lactating females were only captured from August to March, while very young individuals were only captured from October to March. Thus, the reproduction of H. fumosus would be partly seasonal with an interruption from April to July (end of the short wet season, and beginning of the long dry season). We discussed the potential role of food availability on this seasonality.
 
The present ornithological report for the Camargue covers six years (1995-2000). This time-period was characterized by mild and wet winters (except the winter of 1999-2000 which was very dry but remained mild). The mean temperatures were all higher than those measured previously. Twenty-two new species have been recorded for the first time (their list is given in the introduction of this paper). The following rare species have been observed again: Blue-winged Teal (a ringed bird in Québec/Canada shows the wild origin of at least one of the three birds seen), Lesser Scaup, Ring-necked Duck, Eastern Imperial Eagle, Lanner Falcon, Saker Falcon, Purple Swamp-hen, Great Bustard, Black-winged Pratincole, Great Sand Plover, Sociable Lapwing, Purple Sandpiper, Buff-breasted Sandpiper, Wilson's Phalarope, Audouin's Gull, Arctic Tern, Common Guillemot, Blue-cheeked Bea-eater, Horned Lark, Richard's Pipit, Blyth's Pipit, Isabelline Wheatear, Desert Wheatear, Paddyfield Warbler, Marsh Warbler, Barred Warbler, Yellow-browed Warbler, Red-breasted Flycatcher, European Nuthatch, Rosy Starling, Snowfinch, Trumpeter Finch and Lapland Longspur. Among the species or group of species which are regularly censused, two arboreal herons (Little Egret and Cattle Egret) have dramatically increased their numbers; the 680 pairs of Night Heron and 266 pairs of Squacco Heron in 2000 must be outlined. The Grey Heron stopped its spectacular increase and the Purple Heron continued to fluctuate (1 370 nests in 1996 and 664 nests in 2000). The Greater Flamingo reached the very high figure of 22 200 pairs in 2000 (13 000 in 1996). The breeding gulls and terns in the salines showed some new trends: the Black-headed Gull dramatically decreased (but began to colonize freshwater breeding sites), the Mediterranean Gull reached the very high number of 1 877 pairs in 2000, the Slender-billed Gull maintained its high breeding number (850 pairs in 2000). The four tern species showed the usual fluctuations. The high number of breeding Yellow-legged Gull remained a concern. The salines at Salin-de-Giraud harboured most of the breeding population during this time-period whereas the salines at Aigues-Mortes lost most of their birds. The wintering ducks and coots continued their overall decrease considered as linked to excessive hunting pressure (mostly through disturbance effect of hunting on feeding grounds). The species that have been found breeding for the first time are the Great Cormorant (in 1998), the Great White Egret (first sucessful breeding in 1996), the Eurasian Spoonbill (in 1998), the Eagle Owl (in 2000) and the Pied Wagtail. Among the breeding species, the Collared Pratincole showed a good breeding success in 2000 (42 pairs and 45 fledglings) and several breeding records were found for the Great Spotted Cuckoo. Some species increasingly overwintered: Night Heron, Black Stork, White Stork, Black Kite, Osprey, Common Crane, Stone-curlew, Little Ringed Plover, Common Tern and Pine Bunting.
 
The population dynamics of small populations is attracting a lot of interest from conservation biologists. This can involve declining populations or on the other hand eruptions often related to human activities; reintroduction programmes are also concerned. In particular. attention should be drawn to the serious threats that certain eruptions represent to the biodiversity of the whole system. These questions also concern more theoretical studies in population biology. Notable progress has been made in this domain and it must be taken into account. The congress at Niederbronn attracted more fundamental contributions, which are presented here in abstract form, and contributions from practising conservation biologists which make up the majority of the present publication.
 
The present ornithological report for the Camargue covers six years (2001-2006). This time-period has been marked by an accelerated global warming (the summer 2003 was particularly extreme). Owing to a constant high observation pressure, 18 new species have been recorded and many rare species have been resighted in that region (Camargue, Crau, Alpilles). Among the species or group of species which are regularly censused, the number of breeding Greater Flamingos Phoenicopterus roseus and that of wintering ducks and coots did not show any significant change. The colonial herons have continued either to increase or to fluctuate at a high level. For example, the Great White Egret Casmerodius albus has definitely settled in the delta and the Squacco Heron Ardeola ralloides has reached a new peak of 505 pairs in 2006. More efficient prospection efforts gave more precise breeding numbers for two species of solitary herons, the Great Bittern Botaurus stellaris and the Little Bittern Ixobrychus minutus. New breeding species such as the Great Cormorant Phalacrocorax carbo, White Stork Ciconia ciconia, Eurasian Spoonbill Platalea leucorodia and Greylag Anser anser increased their numbers as well as the Glossy Ibis Plegadis falcinellus of which 14 pairs has bred in 2006 and the Purple Swamphen Porphyrio porphyrio which was found for the first time breeding in 2006. The breeding species showing the most serious concern are actually the breeding gulls and terns whose figures have dramatically decreased. Without human management, this situation will even become worse in a near future. Further remarkable observations were the first case of wintering Lesser Spotted Eagle Aquila pomarina in 2001/2002, a mixed pair of Black-winged Pratincole Glareola nordmanni x Collared Pratincole G. pratincola in 2001, the settling of the Rook Corvus frugilegus in Arles.
 
Over the past decades, many waterbird populations have undergone rapid changes in numbers as well as in distribution. These continuing changes make it necessary to update population estimates on a regular basis. From this point of view, a regular mid-winter survey of wintering waterbirds was carried out in Tunisian wetlands. The overall objective of this paper is to record wintering population sizes for the period 2001-2002 to 2006-2007 and to identify waterbird indicator species relative to these Tunisian ecosystems. The preliminary analysis of the collected information enabled us to define the size and the actual status of wintering waterbird populations in Tunisia. A total richness of 106 species (3 common, 18 frequent and 85 rare ones), belonging to 23 families and 10 orders, was identified. The most abundant species, which accounted for about 90 % of the total abundance, were: Calidris alpina (18.7 %), Phoenicopterus ruber (13.6 %), Aythyaferina (11.4 %), Fulica atra (10.7 %), Tringa totanus (5.9 %), Larus michahellis (5.2 %), Larus genei (3.9 %), Anas penelope (3.7 %), Calidris minuta (3.5 %), Anas clypeata (2.2 %), Larus ridibun-dus (2.0 %), Charadrius alexandrinus (1.9 %), Phalacrocorax carbo (1.6 %), Vanellus vanellus (1.4 %), Plu-vialis squatarola (1.3 %), Anas platyrhynchos (1.3 %), Anas crecca (1.3 %) and Numenius arquata (1.1 %). With an average of about 427 300 birds per year, Tunisian wetland areas play an important role in waterbird populations conservation due to their large habitats, high productivity and geographical position connecting European and African continents. Considering the Ramsar Criterions, a total of 20 sites appear as internationally important. Indeed, 3 sites individually and regularly held more than 20 000 birds and should be classified as internationally important: Kneiss islands (72 368 birds per year), Ichkeul National Park (91 587 birds per year), and sebkhat Sejoumi (29 276 birds per year). Together, these wetlands host about 45 % of the total national population sizes. Three other sites are also potentially important, recorded as hosting more than 20 000 wintering birds at least once: Kerkennah islands (16 608 birds per year), Jerba island (14 962 birds per year) and sebkhat Ariana (19 122 birds per year). The 1 % threshold for use in Ramsar Convention was met for 14 species (Sterna sandvicensis, Larus genei, Platalea leucorodia, Grus grus, Charadrius alexandrinus, Phoenicopterus ruber roseus, Pluvialis squatarola, Calidris minuta, Calidris alpina, Tringa totanus, Anser anser, Anas penelope, Aythya ferina and Fulica atra) and was exceeded in 10 wetlands. Among all species, 6 are globally threatened (Marmaronetta angustirostris, Aythya nyroca, Oxyura leuco-cephala, Gallinago media, Limosa lapponica and Larus audouinii) and were regularly observed in 10 sites. Application of the global ANOVA Kurskal-Wallis test to data relative to species richness, mean abundance and Hill (N1 and N2) diversity values reveals highly significant differences between the 8 wetland classes. However, the spatial organization of aquatic birds doesn't reflect any clear gradient. The ANOSYM test discriminates two major associations: artificial versus natural habitats. The latter are themselves organized into 3 sub-associations according to permanence of water and marine influences. Despite these important carrying capacities of Tunisian wetlands, natural factors and human exploitation have greatly modified many of these ecosystems through habitat loss and fragmentation. Thus, it appears essential to use appropriate strategies, like indicator species method, to enhance the value of these areas for waterbird species, which are very sensitive to habitat changes. In the present case, based on the SIMPER analyses method, 15 species are indicators of the wetland status: Phoenicopterus ruber, Charadrius alexandrinus, Calidris alpina, Larus michahellis, Ardea cinerea, Bubulcus ibis, Ciconia ciconia, Vanellus vanellus, Grus grus, Phalacrocorax carbo, Larus genei, Fulica atra, Tachybaptus ruficollis, Aythya ferina, Podiceps cristatus and Anas platyrhynchos. Besides their fundamental interest and importance, results of the present study can be essential to the application of conservation programs.
 
Monitoring of coral reefs in Martinique started in 2001, after the first permanent IFRECOR survey site was created in the island. Four permanent transects of 60 m long are sampled twice a year during the dry and the wet season in the area. Benthic community cover and fish assemblages are assessed using scuba diving techniques. The benthic communities composition remained stable, while already degraded, until end 2005 with average coral cover values of 38.7 % over the Southern reef sites and 22.9 % on the Atlantic coast. The major bleaching event during the second semester of the year 2005 killed about 14 % of the coral colonies in Martinique. Beginning 2006, a disease outbreak also killed another 15 % of the corals, with significant differences between species. Globally, although coral reef decline had started before these events, an average of 30 % of the coral reefs of Martinique disappeared during the past 2 years. Thereby, there was a decrease in the average coral cover down to 32.9 % (South Caribbean) and 14.8 % (Atlantic). No effect has been recorded yet on coral reef fish assemblages in terms of total biodiversity, individuals and biomass. Global climate change and anthropogenic pressures are principally involved in the coral reef ecological status in Martinique. Regional MPAs projects are under review and could be an environmental issue for coral reef protection and preservation in the future.
 
New Caledonia is located in the Southwest Pacific. This French territory is in charge of the management of its coastal environment. In 2004, 230,789 inhabitants lived in New Caledonia, 63 % in the region of Nouméa capital city (South Province). The gross domestic product is similar to West European countries. New Caledonia holds 25 % of the known nickel reserves, nickel exports constituting 90 to 95 % of the country's exports. Coral reefs and lagoons cover 40,000 km . These ecosystems are among the most diversified on earth with 150 types of reef and 15,000 marine species. New Caledonia coral reefs applied for the World Heritage list in 2007. In 2001, 1,212 t of marine resources were exploited, mainly fish (690 t). The impacts of tourism are located around Nouméa capital city and cruise ship stopovers. Yachting has a higher impact on coral reefs close to Nouméa and the major villages. MPAs (covering more than 420 km2) have been created, most of them with moorings, to limit these impacts. Coral reefs are also impacted by mining activities and sewage. However, new managing policies (extracting procedures, wastewater treatment plants, disposal areas) are being implemented to limit these impacts. Research on coral reefs is made by French agencies and NGOs. The first coral reef observatory (ORC) was created in 1997 in the South Province. Its activity had stopped in 1999 because of a lack of funding. The observatory (RORC, 30 stations) was reactivated in 2003 and funded by IFRECOR. New Caledonia is a member of the SW Pacific node of the GCRMN and contributes to the 'Status of coral reefs of the world' reports and Reef Check program (since 1997). Since 2003, coral reefs remained in a relative good health (83 % of the stations) despite the impact of cyclone Erica (2003). The density of fish and invertebrates (selected species) did not change significantly. The percentage of live coral cover has stabilized after the impact of Acanthaster on selected sites the previous years. Unlike other SW Pacific Islands, New Caledonia was not affected by a major bleaching since 1996. In the future, New Caledonia will have to face an increase of fishing activities around new mining centres, and increase pollution from urban centres (sewage, solid waste, etc.). In conclusion, there is a dire need to implement a perennial observatory of coral reef health.
 
-Localisation des principaux récifs coralliens de l'île de la réunion (a :bancs récifaux ; b : plateformes récifales ; c : récifs frangeants). Position des stations de suivi de l'état de santé (÷). Location of the main coral reefs of Reunion island (a : reef banks ; reef plateforms, c : fringing reefs). Location of the monitoring stations (÷).
-Évolution entre 1998 et 2006, sur les stations de platier, du recouvrement moyen (exprimé en cm +/-erreur standard) en faune benthique et substrat par catégorie et par transect de 20 mètres : (a) coraux, (b) algues, (c) abiotique, (d) autres organismes. Evolution between 1998 and 2006 on reef flat of the mean cover (in cm +/-standard error) of benthic fauna and substratum by category along 20m-long transects : (a) hard coral (b) algae (c) abiotic (d) others.
— evolution des abondances moyennes par transect et par catégorie trophique des peuplements ichtyologiques sur les stations de platier. Evolution of mean abundance by transect and by diet of fish assemblages at reef flat stations  
— Évolution entre 1998 et 2006, sur les stations de pente externe, du recouvrement moyen (en cm +/erreur standard) en faune benthique et substrat par catégorie et par transect de 20 mètres : (a) coraux (b) algues, (c) abiotique, (d) autres organismes. Evolution between 1998 and 2006 on the outer reef slope of the mean cover (in cm +/standard error) of benthic fauna and substratum by category : (a) hard coral, (b) algae, (c) abiotic, (d) others.  
Réunion Island is 2500 km2 and belongs to the outermost regions of European Union (EU). The population attained 774 600 inhabitants in 2004 with 25 % living in the western part of the island, 80 % in the littoral zone (called «bas»). The gross domestic product (GDP) per capita is less than 50 % of the mean index of the EU. The rate of unemployment was of 33 % in 2004. Coral reef ecosystems extend over 12 km2 along 25 km of the west and south coasts of the island. In addition to the natural influence of climatic events (global change) coral reef ecosystems are impacted by direct and indirect influences of the increase of human population. Direct impacts are mainly due to human overfrequenting of reef flats and overfishing. Indirect impacts are due to urbanization and to industrial, agricultural and urban pollutions. The competence in marine environment is assumed by an administration (Direction Régionale de l'Environnement). Researches on coral reefs are run by research institutes and NGO. The first coral reef monitoring network was set up in 1998 on the Saint-Gilles/La Saline reef. Since then, it was extended to the three other main reef units (Saint-Leu, Étang-Salé, Saint-Pierre) and the data are gathered since 2001 by ecoguards of the association «Parc Marin de la Réunion», with the partnership of the university (Laboratoire d'Ecologie Marine). Data are stored in a database (COREMO) and analysed by ARVAM (Agence pour la Recherche et la Valorisation Marine). The operation is funded both by the state administration and a local administration (Conseil Régional). Réunion Island is a part of the South-West Indian Ocean node of the Global Coral Reef Monitoring Network (GCRMN). It is regularly involved in the writing of the «Status of coral reefs of the world». At the same time another network involving stakeholders is built using the Reef Chek protocole. At the present time, coral reefs of Réunion Island are deteriorated. If the density of the targeted species of fish has not changed since 1999, the surface of live corals has shown a significant decrease on half of the 14 stations, particularly after two bleaching events in 2003 and 2004. The various negative impacts due to human activities contribute to weaken these ecosystems and to decrease their resilience. Hence, they are less and less able to resist exceptional climatic events (hurricanes, swells) and the bad impacts of global change (bleaching). To face to the stake of long term development, 75 % of the reef units of the island are protected since February 2007 by the status of «Réserve Naturelle Nationale Marine» (35 km2 of marine protected area).
 
— Espaces protégés et stations de suivi de Mayotte. Protected species and monitoring sites on Mayotte.  
– Évolution de la vitalité des récifs frangeants de 1989 à 2004. Coral reef vitality modifi cations on fringing reefs from 1989 to 2004.  
– Évolution du substrat des différents sites Reef Check. Substrate modifi cations on Reef Check sites.  
The principal characteristics of Mayotte Island are the length of the reef-barriers delimiting one of the widest lagoon of the area, a double reef-barrier (uncommon geological structure) as well as a general dynamics being equivalent to that of a series of eight reef-lagoon complex being able to function independently. Specificities of the environmental parameters combined with the particular characteristics generate a singular dynamics of the ecosystem and addicted communities. The objective of the Observatory of the Coral Reefs of Mayotte is to ensure, on the long term, the acquisition of reference data on the coral ecosystems of the island in order to evaluate the spatio-temporal evolution of the benthic and ichtyologie communities, this associated with more specific objectives (will ciguatera, whitening, SIG, coordination and management). To succeed in doing that, regular surveys are carried out (station of reference ORC, fringing reef, Reef Check), associated with specific studies and initial states. More than 9 years after the phenomenon of massive whitening, the results of the ORC show a continuous and encouraging evolution of the coral growth. However, the dynamics of substrate recolonization by new individuals varies according to the three types of reefs present.
 
— (a) Localisation géographique de la zone d'étude dans le versant nord du Haut Atlas et (b) carte simplifiée des sols de la région (cavallar, 1950). le site d'étude est signalé par ().  
A pedological and anthracological study carried out in the Moroccan High Atlas mountains on the soil profile along a slope currently occupied by Quercus ilex subsp. ballota (Dcsf.) Samp., allowed us to reconstruct its history and to account for changes in vegetation after major events whether climatological or anthropogenic. The analysis of the profile reveals two superimposed soils. The organic matter at the base of the slope (1400 m) shows an abnormal distribution with a deep horizon (55 - 70 cm) enriched in organic matter including many fragments of charcoal, which indicate a fire dated at 4300 - 4100 cal. BP. This horizon represents the old soil surface covered by colluviation on which a new soil has formed. The latter represents a surface organic horizon which is rich in charcoal dating back to 80 cal. BP. The anthracological study shows the existence of charcoal of Aleppo pine (Pinus halepensis Mill.) dating back at about 3800 years BP (about 4300 - 4100 cal. BP). The presence of this species, whose current upper limit is located at about 200 m lower down, indicates the existence of fires occurring during dry periods already revealed in the western Mediterranean between 5300 and 3400 cal. BP. The other plant remnants indicate a vegetation consisting mainly of Cistus sp. and Quercus sp. This study shows, thus, the salient role of Mediterranean forest fires in the spatial-temporal redistribution phenomena of plant species and also in the dynamics of terrestrial ecosystems.
 
An analysis was made of treatments to promote the germination of Cistus clusii (Cistaceae), attempting to simulate some abiotic factors (thermal shock) and biotic factors (gibberellic hormones and chemical scarification) of the natural habitat of this species. Germination was increased by chemical scarification (such as may occur when seeds pass through the digestive tract of a mammal) and thermal shock (such as may occur during forest fires). In the latter case, both the intensity and duration of the treatment were determining factors. The study of the germination capacity after a chilling period showed that, in addition to the dormancy imposed by the seed coats characteristic of the family Cistaceae, in this species physiological dormancy occurs at the embryo level. These results complement the currently available data on the characteristic dormancy processes of Cistaceae seeds, for which dormancy other than that imposed by the seed coats has rarely been described.
 
A comparative study of snake community composition of 45 tropical forest patches, including both original and literature data, is presented. Twelve study areas are situated in Nigeria, one in Cameroon, and 30 in Madagascar. Two forest sites from Panama were also used as outgroups. There was a remarkable consistency among sites in inter-regional comparisons in terms of mean number of species observed x min.-1. The highest similarities were between Nigerian and Malagasy sites and between Cameroon and Nigerian sites, whereas similarities between all these African sites and Panama sites were lower. Altitude and linear distances among sites did not influence significantly the snake species detection and abundance. Nigerian sites had comparatively higher numbers of semi-aquatic taxa than Malagasy sites. The terrestrial guild was the dominant one, and the arboreal guild was constituted by a remarkable diversity of species, in nearly all sites of both Nigeria and Madagascar. There was a very low diversity of syntopic fossorial species in both Nigeria and Madagascar (in all 22 study plots, only 1 or 2 fossorial species were found). In Nigerian sites there was a general prevalence of primarily lacertophagous and mammalophagous species, but batracophagous and ornithophagous species were also quite abundant. In the Malagasy sites lacertophagous species were significantly prevalent, followed by batracophagous species, whereas species with other dietary preferences (e.g., mammalophagous) were much under-represented. The abundance of species feeding on invertebrates and of generalist species was similar in the two geographic regions, whereas piscivorous species were found only in the Nigerian sites. The scarcity of mammalophagous, piscivorous and ornithophagous species in Madagascar could be interpreted as a general biogeographic pattern in terms of food type availability (taking into account the scarcity of some types of prey in Malagasy forests and freshwater streams) as well as in terms of snake size distributions. With regard to snake body size distributions in the various examined communities, it appeared that forest environments of both Nigeria and Madagascar can house a similar snake community as for numbers of species < 2 m in length, but Nigerian environments can harbour numbers of giant and very large species (from 2 to 9 m in length) that cannot be hold in Malagasy forests. The ecological patterns emerged in this comparative study are discussed in the light of current community ecology theory and biogeography.
 
The relationship between body size and population abundance was studied in summer dung beetle communities of three South-European mountains: southern Alps (France), eastern Pyrenees (France), Sierra de Gredos (Spain). Middle-sized species dominated in southern Alps and in the Sierra de Gredos, but the large-bodied species (Geotrupinae) presented the highest population densities in the Pyrenean communities. The domination of large-bodied species in the Pyrenees was linked with a noteworthy low diversity (under-representation of Aphodiinae and Coprinae). Our results showed (i) that the relationship between body size and population density does not present a homogeneous pattern in South-European dung beetle communities. So, the study of local assemblages does not allow to infer underlying evolutionary trends. (ii) Conversely this analysis allows to assume that interspecific competition played a main role in the formation of the Pyrenean fauna. Three hypotheses are proposed to explain the specificity of Pyrenean communities.
 
European rabbits (Oryctolagus cuniculus) are the major prey in Spain for several endangered carnivores and raptors. In recent years, many different efforts have been directed at increasing rabbit populations, and thus enhancing the survival of these endangered predators. The aim of this work was to improve our understanding of the factors that influence the natural variation in rabbit populations, specially those regarding on the food abundance and quality, and to discuss the efforts actually used to manage rabbit populations. Estimates of rabbit abundance were obtained monthly from roadside counts during a 25 month period developed at Donana National Park. Simultaneously, samples of the herbaceous layer were obtained from the area covered by censuses. Fluctuations in rabbit abundance were compared with changes in biomass and quality of the herbaceous plants. Rabbit abundance showed the best fit with the total protein availability in the herbaceous layer. Variations in the precipitation pattern between years, which affected both food availability and rabbit reproduction, and the incidence of the first epizootic of the rabbit hemorrhagic disease, caused the observed differences between maximum values of rabbit abundance in two consecutive years. The relative importance of other factors influencing rabbit numbers in Donana including myxomatosis, predation, and competition for food with large herbivores is discussed.
 
A field survey conducted with a R.O.V. submarine system has been carried out for the first time between 100 and 400 m deep on the volcanic slopes of Reunion Island. 20 dives were conducted in the south-east of the island on the recent volcanic lava flows, and 13 dives were conducted in the west coast, associated with older geological substrates. Pillow-lavas have been recorded at a depth of 250 m on the 2007 lava flows, proving that the lava has burst at these depths, causing disturbance in the depths and up to several miles around. Pebble conglomerates were also observed in the north-west, in St-Paul Bay, between 100 and 200 m in depth, connecting to Rivière des Galets alluvial cone. Big collapses show that the substrate remains unstable in this area at deep depth. Concerning the communities, we have made an inventory of many species and more particularly 66 species of fish, 16 species of cnidarian, 8 species of arthropods and 7 species of echinoderms. Some of them have never before been observed in Reunion Island.
 
This work has focused on the study of germination characteristics of seeds of Acacia tortilis (Forsk.) Haync subsp. raddiana (Savi) Brcnan, a species native of Tunisia, and of two introduced species: Acacia salicina Lindl. and Acacia ampliceps Maslin, reforested in arid zones of Tunisia. Germination was followed under conditions of water and salt stresses. Pre-trcatmcnts designed to remove integumentary inhibitions were applied to seeds. The germination behaviour of acacias in osmotic stress conditions snowed a treatment effect, concentration of PEG 6000, highly significant on germination rate and mean time of germination. We found that these species did not tolerate drought and we observed a complete inhibition of germination at -0.8 MPa. The study of the effect of salt stress on germination showed a better tolerance of Acacia tortilis (Forsk.) Haync subsp. raddiana (Savi) Brcnan to salinity than the other two species as it germinated at high salt concentrations. Indeed, at 18 g/1 the germination rate reached 32 %. We didn't find any relationship between seed gcrminativc properties and ecology of the adult plant.
 
It is assumed that forests can serve multiple uses, including wood production and maintenance of high biodiversity level. We tested this hypothesis by studying eradication methods of invasive plants currently implemented in exploited endemic Acacia heterophylla forests located in a tropical highland forest region on the island of Réunion. We also compared species richness in logged (over time) and natural forests. Our results show that all individuals of the widespread alien invasive plant Rubus alceifolius were generated from cuttings. We quantified the high growth capability of this species by comparing with those of Acacia heterophylla along with Rubus apetalus var. apetalus, a close non-invasive congener. The substantial multiplicative and vegetative growth ability of R. alceifolius enabled it to form monospecific patches in only 2.5 years. The species richness of the exploited Acacia heterophylla forest was thus very affected. Although the species richness increased over time after logging, the extent of the resulting richness was not as great as that in natural forests which, moreover, included numerous exotic plants. The authors assess the impact of highly disturbing logging operations and, based on the results of the comparisons, are very pessimistic about the possibility of maintaining species richness in logged forests. Nevertheless, the results indicate that the situation is not beyond hope and an eradication program specifically tailored to this kind of forest is proposed if exploitation will stop.
 
The present study was conducted in the Bouhcdma national park and its surroundings, located in the arid area of Tunisia and considered a Biosphere reserve by UNESCO in 1977; it is a protected area with special ecological characteristics and an important dynamics of space occupation.Thc park contains the only wooded steppe with Acacia tortilis (Forsk.) Hayne subsp raddiana (Savi.) Brcnan var. raddiana Brcnan in Tunisia. With the aim of safeguarding and management of the park, a better knowledge of the distribution patterns and dynamics of the vegetation of this zone makes it possible to consider programmes of restoration and sustainable management of the natural environment. Based on the interpretation of remote sensing data and use of SIG, the study was devoted to the elaboration of charts relating to the ecological systems present in 2005, and to the distribution of the steppe with Acacia tortilis according to physical factors such as slope, altitude, type and depth of the soil. Also, the production of seeds was studied to explain the effect of physical factors on the regeneration of the species. The analysis of soil occupation dynamics translates into a good distribution (7056 ha) of steppe with Acacia tortilis. The study shows that Acacia tortilis is located on 6242 ha at an altitude of 20 m to 150 m and on 814 ha at an altitude from 150 to 250 m. This species grows on 5815 ha with a weak slope (0 to 3 %), on 928 ha with a slope of 3 to 5 % and only on 313 ha with a slope > 5 %. The results show that the Acacia tortilis is regenerated on the not very advanced soil of hydrous contribution with a surface of 3832 ha, on rendzina with 1280 ha, the isohumic soil with a surface of 986 ha. Acacia tortilis colonizes the far from deep soil with a surface of 2796 ha, the fairly deep soil with a surface of 2175, the very deep soil with a surface of 1970 ha, the not very deep soil with a surface of 75 ha and the deep soil with a surface of 40 ha.
 
Woody stand structure in plantations of Acacia Senegal (L.) Willd in Dahra area (Ferlo, Senegal). - The present study gives an up-to-date inventory of natural woody stands in plantations of Acacia Senegal (L.) Willd in Ferlo. It aims at determining the structure, specific composition and regeneration of woody stands in plantations of Acacia Senegal. Four sites were retained for study: Acacia Senegal plantations Ndodj 2001, Isra 1999, Boulal 2004 and Déali 2005, distributed along an increasing pluviometric gradient, with different topographic characteristics and protection status. Woody stands were characterized by dendrometric measurements. Woody plants belong to 12 species representing 10 genera and 7 families. The very high mortality rate observed on dunes would be linked to poor water availability. Regeneration appeared significant in hollows (Isra), especially concerning Boscia senegalensis (Pers.) Lam and Balanites aegyptiaca (L.) Del. It was also relatively important at Boulal where livestock is rather infrequent, as in Isra. On the other hand in Déali, regeneration was important at the top of the dunes with Calotropis procera Ait. and weak in hollows, areas frequented by the cattle. Compared to Ndodj, Boulal was characterized by a relatively high regeneration. This Situation could be explained by the fact that Isra and Boulal are more protected than Déali which is much attended by the cattle. In Ndodj, we noted that plants are subject to attacks by termites what explains the high mortality rates observed in this site. Balanites aegyptiaca, Boscia senegalensis and Calotropis procera are at the origin of the increase of the number of individuals in the stand, whereas Acacia Senegal shows a weak regeneration. This weak regeneration of Acacia Senegal would be linked to the systematic gathering and collecting of fruits, abundantly used to feed domestic animals, but also at certain places to Stripping and repetitive bleedings. As far as plant circumference and height are concerned, the observed distribution was unimodal for the shrub layer, except in hollows at Isra where it was bimodal in the shrubby as well as the arborescent layers. Field observations and obtained results show that floristic variability was more marked at Isra than at Déali (strong pressure of the cattle). The structure of the woody stand appeared strongly dependent on topography, moisture gradient and anthropic pressure.
 
In the course of a research program on the mites ot the genus Dermanyssus, parasites were collected in 2007 and 2008 on live adults and young as well as on complete (alter the young Hedged) or partial (unsuccessful or old) unoccupied nests of Common Swift (Apus apus) in Gard (southern France) and Pallid Swift (A. pallidus) in Corsica. Two mite species were found: Dermanyssus gallinae (on Common Swift, but sampling could have been too small for Pallid Swift) and above all a new species Dermanyssus apodis (on both Common and Pallid Swifts) which has been described in 2009. The eventual effects of these parasites on their hosts are briefly discussed.
 
This study aims at determining breeding chronology and reproductive parameters (clutch-size, egg volume, hatching success and chick survival rates) in two Yellow-legged Gull Larus michahellis colonies showing a marked difference in anthropogenic food resources accessibility. For instance, one of the colonies studied, established on Ratonneau island, is very close to the large refuse dumps of Marseille city while the other, established on Bagaud island, is 30 km distant from the nearest refuse dump. The mean laying date of the first egg showed a significant difference between the two colonies. Although mean clutch-size does not significantly differ between the two colonies, complete 3-egg clutches were more frequent at Ratonneau. Mean egg volume was significantly different between the two colonies with a markedly smaller volume for the C-egg in the colony that was farther from human food sources. Moreover, hatching success and chick survival rates were significantly lower on Bagaud than on Ratonneau. All these differences may be linked to marked differences in resource accessibility, and in this way, anthropogenic food resources accessibility may be partly responsible for the clear difference in the demographic patterns of the two colonies for the last twenty years. These results could be used to calibrate more accurately certain demographic modelling in order to improve the population management of this superabundant bird species.
 
The lagoon of Bizcrtc underwent a mixed anthropic pollution, essentially enhanced by the unlimited industrial waste derived from Iron Factory "El Fouledh", Industrial Refining Tunisian Company, Cement Company and from 400 industrial units established around it. This waste includes major pollutants conducive to a degradation of the ecological conditions of this lagoon. Previous research dealt with most of the different ecosystem components: soil, sediments, water, and aquatic organisms. In the present study, we have been interested in the halophytes inhabiting the edges of Bizcrtc lagoon. This study would allow us to identify the accumulating species to be used in the programs of phytorcmediation. Shoots of Atriplex porlulacoides, Arthrocnemum indicum, Salicornia arabica and Suaeda fruticosa were harvested, rinsed, dried and then crushed. Analyses were focused on few trace metals: Pb, Cu, Zn and Cd. Our results have allowed us to classify the halophytes "A. porlulacoides, A. indicum, S. arabica and S. fruticosa" among the accumulating species of Pb (respectively 84.6,92.2, 102.9 and 86.3 μg.g-1 DW), of Cu (respectively 14.5, 15.1, 24.2 and 14.9 ug.g-1 DW) and of Zn (respectively 1370.1,625.1, 1601.4 and 772.5 μg.g-1 DW). Also, A. porlulacoides and S. arabica are distinguished by their ability to store significant amounts of Zn which gives them a potential utility in the remediation programs. As regards Cd, we have shown that all studied species arc hyper-accumulators of this metal (A. porlulacoides: 274.0 μg·g -1 DW; A. indicum: 280.4 μg·g-1 DW; S. arabica: 211.6 ug·g-1 DW and S. fruticosa: 209.0 ug.g-1 DW). It should be noted that the harvested halophytes do not show any sign of toxicity, and they are able to accumulate more important amounts of heavy metals and to tolerate the metallic stress. These results show that the studied halophytes can be recommended for all programs of phytorcmediation in polluted and salty areas.
 
Research was performed m Banco National Park (Ivory Coast) in order to locate Achatimdae snails inside this park and identify which factors condition the choice of these microhabitats. It resulted that (i) there are several preferential microhabitats for Achatinidae : these are the litter, the soil, the leaves, the herbs, the branches and the dead or living tree trunks ; (ii) Achatina achatina, Archachatina marginata var. eduardi, Archachatina marginata var. egregiella and Limicolaria flammea are addicted to the soil and/or the litter, while Achatina fúlica and Lignus intertinctus prefer higher locations (herbs, leaves). Archachatina ventricosa seems to adapt itself to all microhabitats ; (iii) microhabitat selection is conditioned by factors such as floods or drought episodes which lead some species to find shelter high in the vegetation or to bury themselves into the soil where they stay in a slow motion state.
 
Diet of the Reed Warbler (Acrocephalus scirpaceus) was estimated by means of forced regurgitations of captured individuals during autumn migration at Kerbacha and Sidi Bou Ghaba, two wetland sites located respectively on the Mediterranean and Atlantic coasts in Morocco. Overall, 88 emetic samples were collected and 17 prey taxa were identified from 789 food items with a predominance of wasps (Hymenoptera) and beetles (Coleoptera) at Kerbacha, and ants including alate forms (Hymenoptera) at Sidi Bou Ghaba. Prey diversity and taxonomic distribution differed significantly between the two sites. Birds at Sidi Bou Ghaba had a lower food intake but fed on larger and less mobile prey than at Kerbacha where most diet samples comprised a large number of small flying prey. These between-site differences are assumed to reflect local food availability and may partly explain the different migratory strategies observed. The short stay and high fattening rate of Reed Warblers at Kerbacha can be associated with the high food intake of a few, abundant prey. The longer stopover duration and lower fattening rate at Sidi Bou Ghaba can be associated with higher diet diversity and lower feeding rate suggesting that prey abundance is globally low except for ephemeral patchily distributed food source such as swarms of flying ants, which are extensively exploited by Reed Warblers whenever available.
 
― Percent frequency of occurrence of lizards and snakes across plantation types in southern Nigeria.  
― Dendrograms of the dissimilarities (Ward's method) across plantation types in terms of frequency distribution of the number of reptile individuals by species, for each of the three main study areas, during the dry season. Numbers along branches derived from 40 bootstraps. Symbols for plantation types follow materials and methods. a): Eket; b) Port Harcourt; c) Yenagoa.  
-Dendrogram of the dissimilarities (Ward's method) in terms of frequency distribution of the number of reptile individuals by species across all the sampling plots, with both plantation types and main study areas indicated. Symbols: EK = Eket; PH = Port Harcourt; YE = Yenagoa. Symbols for plantation types follow materials and methods.
― Dendrograms on species dissimilarities (Ward's method) in terms of frequency of observations across plantation types by study area, during the dry season. Numbers along branches derived from 40 bootstraps. a): Eket; b) Port Harcourt; c) Yenagoa. Symbols for the various species are presented in Tab. VIII.  
Dendrograms on species dissimilarities (Ward's method) in terms of frequency of observations across plantation types by study area, during the wet season. Numbers along branches derived from 40 bootstraps.a): Eket; b) Port Harcourt; c) Yenagoa. Symbols for the various species are presented in Tab. I.  
Despite many studies of reptile community composition in Africa, no studies document the variation of reptile assemblages across different plantation types. Here, we document the community composition (richness, taxonomic composition, dominance, evenness) in relation to seasonality in eight different plantation types (from cassava-yam to banana-plantain, and from cacao to mixed orchards), and at three distinct study areas in the River Niger Delta of southern Nigeria. Our study showed that the community composition of reptiles did not differ significantly across plantation types in terms of species diversity and richness during the wet season, but it did so during the dry season (possibly as a consequence of survey effects). A few highly dominant lizard species (Agama agama and Trachylepis affinis) constituted the great majority of the specimens encountered during field work. Some snake species, although usually not very abundant (in terms of relative number) were observed in nearly all sites. Typical forest specialists may enter plantations, but they were never abundant there. Tortoises did not occur in any plantations. Diversity indices and multivariate sets of analyses revealed minor differences among study areas and across plantation types in terms of community composition patterns. However, some types of monoculture plantations had higher dominance and lower evenness values than mixed orchards (= poly-culture farms), showing that monocultures provided least quality habitats for reptile communities than poly-culture farms, favoring few species due to the relatively homogeneous niche availability. Overall, a clear process of biotic homogenization, with increases in dominance, was clearly observed at all sites.
 
In this paper we adapt a recently developed objective framework to assess which species may require monitoring, vigilance or enhanced prospection for the protected flora (124 taxa) present in the Pyrenees National Park (France). The method is based on three criteria: regional responsibility, local rarity and habitat vulnerability. The first two criteria were quantified by adapting classes according to previous work. The vulnerability criterion was quantified using three main parameters: the priority and conservation status of the habitat of each species combined with the proportion of known occurrences of the species in the « adhesion » area of the park which is not subject to regulatory control. Each species was ranked within a hierarchy developed in collaboration with the different park staff which allowed precise taxa to be selected for monitoring, vigilance and prospection.
 
In winter, dabbling ducks generally use a set of two distinct habitats over the 24-hour cycle, resting in large groups on a few large waterbodies during daylight hours, and dispersing at night into many smaller feeding habitats. In some circumstances, birds use the same site during both daylight hours and during the night. This study was conducted on a small (< 1 ha) pond used by Teal (Anas crecca) by day and by night in the early part of the winter. Duck numbers were not related either to the abundance of food resources, water levels or pond area. Teal had the same pattern of behaviour during daylight and at night, foraging being the main activity through the whole period of their presence on the site. Comfort activities decreased with increasing water levels and pond area, perhaps because the predation risk is greater in these conditions. This study contributes to understanding the factors affecting the use of diurnal feeding sites by Teal.
 
Anabasis aretioides, endemic to North Africa, is a cushion-forming plant particularly well-adapted to the climatic constraints of arid zones. This shrub is exploited by the local population for kitchen fuel, as a medicinal plant and for staking Saharan trails. We conducted a survey of the structure, mortality and recruitment in four Algerian populations in order to determine the impact of climate and human exploitation on A. aretioides dynamics. Our results show that the species is declining dramatically and that ovcrcxploitation combined with unfavourable climatic conditions arc responsible. In three out of the four populations studied, the number of individuals dropped by half between 1994 and 1997, and there were not enough individuals to continue the survey in 2004. Recruitment was sporadic, with no regeneration during several years at some sites, but wc found no relation with climatic conditions. However, regional climate seems to be the most determinant factor for plant growth: high growths were measured at all sites in 1996, and at the Mazzer site in 2006 and 2010, all corresponding to years with moderate to high rainfall. Although the results of the present study remain exploratory, they nonetheless raise concerns regarding the conservation and structures of A. aretioides populations in South-Wcst Algeria.
 
Top-cited authors
Luca Luiselli
  • Rivers State University of Science and Technology
Alexandre Gannier
  • Groupe de Recherche sur les Cétacés
Matthieu Guillemain
  • Office français de la Biodiversité
Jean-Louis Chapuis
  • Muséum National d'Histoire Naturelle
Hervé Fritz
  • CNRS & Nelson Mandela University