The spatial and seasonal variability of the microphytoplankton and ciliates communities in relation to the environmental factors were studied in the southern coastal area of Sfax. Results revealed a striking difference between seasons regarding pH, with strong acidification in autumn generated by industrial activity. Spatial distribution of pH in autumn impacted the microorganisms in different ways: acidic stations to the south showed significant correlations with Cyanobacteria, dinoflagellates and loricate ciliates whereas higher pH values in spring (pH > 8) were linked to diatoms richness. The high availability of inorganic phosphate is associated with the high release of phosphate due to residue from a phosphate treatment manufacture along the coast; consequently, N/P ratios were low (1.34–13.43) suggesting nitrogen limitation. Microphytoplankton abundance shifted from dinoflagellates dominance in autumn to dominance of diatoms during winter and of Euglenophyceae in summer. Loricate ciliates accounted for the largest proportion of the ciliates community while aloricate ciliates were relatively scarce during all seasons. Variability of ciliate community appeared not directly linked to environmental conditions, but significant positive relationships between abundance of loricate ciliates and microphytoplankton suggest that these ciliates may feed on microphytoplankton.

The reproductive dynamics of swordfish (Xiphias gladius) was investigated from catches of the Reunion Island-based longline swordfish fishery between 19–25 °S and 48–54 °E. Thus, 1727 swordfish (size range 75–289 cm, lower jaw-to-fork length, LJFL) were sampled on board commercial fishing vessels during the period of May 1998 to January 2001. Reproductive activity was assessed using macroscopic gonad characteristics, trends of gonadal indexes for both sexes, oocyte size-frequency distributions and microscopic investigation of oocyte development stages. Size at first maturity (L50) for female and male swordfish was estimated in Indian Ocean for the first time. L50 was estimated at 170 cm and 120 cm (LJFL) for females and males, respectively. Spawning occurred from October to April in the vicinity of Reunion Island where sex ratio of caught populations fluctuated seasonally. The seasonal changes in sex ratio and the incidence of larger individuals at the beginning of the spawning season provide some preliminary indications of synchronized movements of swordfish between spawning grounds and neighboring regions. Our results add significantly to knowledge about the reproductive biology of swordfish in the southwestern Indian Ocean. An overview of the available information on reproductive biology and dynamics of swordfish in Indian Ocean and eastern Pacific indicated that spawning activity is localized in discrete areas, and showed that there is incomplete information on spawning grounds in this extended area.

Fin whales (Balaenoptera physalus) are the only mysticete regularly found in the Mediterranean Sea. Its exceptional high abundance during the summer period in the north-western Mediterranean is essentially due to productive waters, but outside of this spatio-temporal window its distribution still remains quite unknown. This paper investigates the distribution of the fin whale on large-scales during the 2002–2006 period. Three areas of the central Mediterranean Sea were selected: the Ligurian Sea in the north-western Mediterranean belonging to the Pelagos Sanctuary; the area connecting both Mediterranean basins in the south-western Mediterranean, the Strait of Messina; and the waters surrounding the island of Lampedusa, in the central Mediterranean. Of the 41,270 km covered by the three surveys, a total of 98 sightings was recorded corresponding to 198 fin whales. Results display a year round distribution along synchronic seasonal dispatching, with a feeding behaviour occurrence in the northern part of the Pelagos Sanctuary during late spring and summer. They indicate high abundance in the Lampedusa area from late winter to early spring manifesting feeding activity. In the Strait of Messina, our results point out the importance of this area as a seasonal feeding ground and an important location for regular autumn transfers between both Mediterranean basins. According to the feeding ground in the two Mediterranean basins, whales change foraging strategy, one being single animals or animal pairs searching for prey in the water column while the other strategy is associated with more individuals feeding on the surface. The strategies differ also by their ecological conditions, such as depth affinity and shoreline distance.

A systematic survey of the endophytic assemblages of Quercus ilex in central Spain has been performed, with the goal of evaluating the importance of geographical and seasonal factors on these fungal communities. Four sampling sites were selected; one of them was sampled twice, in the spring and the autumn. The collected plant material consisted of bark, twigs and leaves from eight trees per site. Fungal strains were isolated with the use of a surface-sterilization method with sodium hypochlorite. A total of 2921 fungal strains grouped into 149 ‘species’ or morphological types were recovered. The 10 dominant species, with isolation frequencies >1.5%, were Pyrenochaeta sp., Periconiella anamorph of Biscogniauxia mediterranea (De Not.) Kuntze, Pseudonectria sp., Cryptosporiopsis quercina Petrak, Alternaria alternata (Fr:) Keissl., two undetermined coelomycetes, Penicillium funiculosum Thom, Diplodia mutila Fr. apud Mont. and Ascochyta sp. Medians of fungal species per tree were significantly different among the sampled sites. The isolation frequencies of the dominant species, as well as other less frequent species, were significantly dependent on the sampling site. The degree of endophytic infection and the diversity of fungal species were significantly higher in the spring. The frequencies of all dominant species at one of the sites depended significantly on the season, except for C. quercina, Acremonium sclerotigenum (F & V Moreau ex Valenta) Gams. and D. mutila. Cluster analysis of the whole endophytic mycoflora of the sampled trees suggested that the geographical factor affects the endophytic distribution patterns more significantly than the seasonal factor.

The relationship between axil age and water-holding capacity on the presence and age of immatures of Aedes (Stegomyia) simpsoni (Theobald) complex (Diptera: Culicidae) in cultivated banana, Musa spp. (Musaceae), Colocasia esculenta and Xanthosoma sagittifolium (Araceae) during the rainy and dry seasons at different locations in Uganda is presented. On Masa spp., higher, younger axils were found to contain more water than older Ones. In some seasons these axils held more immatures of Aedes simpsoni complex than the lower, older axils of the plant. On C. esculenta and X. sagittifolium plants, the middle and lower axils held more water, and had a greater abundance of larvae and pupae. There were generally no significant differences (P > 0.05) in the mean age of larvae and pupae found in axils of different ages.

On the basis of hydrological and biological data collected between 1983 and 1987 along the Frenchcoast, and especially in the southern approaches to Brittany. it has been possible to compare differentparameters in an attempt to explain the seasonal variations of a toxic dinoflagellate: Dinophysis sp.speveral species were identified and their seasonal distribution patterns are described. The origin of the blooms, from either coastal endemic or offshore populations, is considered