Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3

seasons Related Abstracts

3 Winter – Not Spring - Climate Drives Annual Adult Survival in Common Passerines: A Country-Wide, Multi-Species Modeling Exercise

Authors: Manon Ghislain, Timothée Bonnet, Olivier Gimenez, Olivier Dehorter, Pierre-Yves Henry


Climatic fluctuations affect the demography of animal populations, generating changes in population size, phenology, distribution and community assemblages. However, very few studies have identified the underlying demographic processes. For short-lived species, like common passerine birds, are these changes generated by changes in adult survival or in fecundity and recruitment? This study tests for an effect of annual climatic conditions (spring and winter) on annual, local adult survival at very large spatial (a country, 252 sites), temporal (25 years) and biological (25 species) scales. The Constant Effort Site ringing has allowed the collection of capture - mark - recapture data for 100 000 adult individuals since 1989, over metropolitan France, thus documenting annual, local survival rates of the most common passerine birds. We specifically developed a set of multi-year, multi-species, multi-site Bayesian models describing variations in local survival and recapture probabilities. This method allows for a statistically powerful hierarchical assessment (global versus species-specific) of the effects of climate variables on survival. A major part of between-year variations in survival rate was common to all species (74% of between-year variance), whereas only 26% of temporal variation was species-specific. Although changing spring climate is commonly invoked as a cause of population size fluctuations, spring climatic anomalies (mean precipitation or temperature for March-August) do not impact adult survival: only 1% of between-year variation of species survival is explained by spring climatic anomalies. However, for sedentary birds, winter climatic anomalies (North Atlantic Oscillation) had a significant, quadratic effect on adult survival, birds surviving less during intermediate years than during more extreme years. For migratory birds, we do not detect an effect of winter climatic anomalies (Sahel Rainfall). We will analyze the life history traits (migration, habitat, thermal range) that could explain a different sensitivity of species to winter climate anomalies. Overall, we conclude that changes in population sizes for passerine birds are unlikely to be the consequences of climate-driven mortality (or emigration) in spring but could be induced by other demographic parameters, like fecundity.

Keywords: Survival, bayesian approach, capture-recapture, climate anomaly, constant effort sites scheme, passerine, seasons

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2 Seasons and Saproxylic Beetles Biodiversity in an Urban Park in Tunisia

Authors: Faïek Errouissi, Zina Nasr


Forest ecosystems are known for its ability to contain a large diversity of fauna especially insects that represent a huge taxonomic group. A portion of forest insects are recognized as saproxylic including the group of organisms that ‘depend on dead or dying wood’ about them, 20% are beetles. We focused our study on saproxylic beetles in an old urban park ‘the park of Belvedere’, located in the north west of Tunis (36° 49'21’ N 10°10'24’ W). The vegetation is dominated by old trees (Eucalyptus, Olea, Aberia, Pinus) and many fallen wood exist. Saproxylic beetles were collected using three interception traps set in the park over one year (from June 2014 to May 2015) and recovered monthly. In total, we collected 189 beetles belonging to 20 families and 57 species. Several saproxylic families (Bostrichidae, Cerambycidae, Curculionidae, Melyridae, Nitidulidae, Staphylinidae), and well known genus (Rhizopertha, Thrychoplerus, Otiorhychus, Dolichosoma, Epuraea, Anotylus) are recorded. We have retained the largest activity of beetles in spring and a very low richness in winter with zero insect per traps. This result was certainly caused by the variation of meteorological factors that mainly influenced the activity of these organisms. Therefore, we were interested on the saproxylic diversity in an urban ‘forest’, and these results will be more interesting when they are compared in the future with other works from natural forest.

Keywords: Wood, seasons, urban park, saproxylic beetles

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1 Influence of Variety, Season and Location on the Distribution of Botryodiplodia Theobromae Associated with the Coconut Fruit Rot Disease

Authors: O. E. Ekhorutomwen, M. E. Udoh, D. E. Esiegbuya


Coconut (Cocos nucifera L.) is an important economic crop in tropical and subtropical areas. Just like other fruits, the pre and post-harvest diseases are major problems encountered by coconut farmers in their plantations. Botryodiplodia theobromae is a pathogen that has been established to be responsible for pre and post-harvest coconut fruit rot disease. In this study, an extensive survey on pre-harvest fruit rot disease of coconut was conducted between July 2017 and June 2019 in order to assess the incidence and distribution of the fruit rot disease across growing seasons in 2 major coconut production areas in Nigeria, precisely Badagry and Benin City. Fruit rot disease incidence was recorded weekly from green dwarf (GD), yellow dwarf (YD), red dwarf (RD), and orange dwarf (OD) coconut in both locations in the coconut production fields. A total of 2158 (between July 2018 to June 2019) and 1171 (between July 2017 to June 2018) coconut fruits from 87 coconut palms randomly selected were examined for this study. Laboratory examination of the infected fruits revealed the presence of Botryodiplodia theobromae. In this study, it was observed that the relative disease incidence and distribution of fruit rot in each sampling location significantly explained the proportion of disease incidence in coconut fruit varieties across the growing seasons. The percentage disease incidence (PDI) of the fruit rot peak in the 2nd and 3rd quarter in both locations and years, was higher in Badagry than Benin City. Botryodiplodia theobromae fruit rot disease show a high percentage occurrence in green dwarf coconut compared to the other coconut varieties in both locations. The incidence and relative abundance of Botryodiplodia theobromae associated with fruit rot disease appear to be influenced by varieties, season, and location in coconut production areas.

Keywords: Distribution, incidence, coconut, varieties, seasons, Botryodiplodia theobromae, rot

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