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Recent anthropogenic climate change is strongly associated with average shifts toward earlier seasonal timing of activity (phenology) in temperate-zone species. Shifts in phenology have the potential to alter ecological interactions, to the detriment of one or more interacting species. Recent models predict that detrimental phenological mismatch may increasingly occur between plants and their pollinators. One way to test this prediction is to examine data from ecological communities that experience large annual weather fluctuations. Taking this approach, we analyzed interactions over a four-year period among 132 plant species and 665 pollinating insect species within a Mediterranean community. For each plant species we recorded onset and duration of flowering and number of pollinator species. Flowering onset varied among years, and a year of earlier flowering of a species tended to be a year of fewer species pollinating its flowers. This relationship was attributable principally to early-flowering species, suggesting that shifts toward earlier phenology driven by climate change may reduce pollination services due to phenological mismatch. Earlier flowering onset of a species also was associated with prolonged flowering duration, but it is not certain that this will counterbalance any negative effects of lower pollinator species richness on plant reproductive success. Among plants with different life histories, annuals were more severely affected by flowering-pollinator mismatches than perennials. Specialized plant species (those attracting a smaller number of pollinator species) did not experience disproportionate interannual fluctuations in phenology. Thus they do not appear to be faced with disproportionate fluctuations in pollinator species richness, contrary to the expectation that specialists are at greatest risk of losing mutualistic interactions because of climate change. [ABSTRACT FROM AUTHOR]

Abstract: The sea surface temperature (SST) in loggerhead turtle breeding areas affects the species reproductive biology. Less is known about the effects of changes in SST in the species foraging grounds. We used nesting data for the Mediterranean loggerhead turtle population breeding on the Greek island of Zakynthos to study the effect of SST in the population foraging grounds upon the initiation of nesting and the number of clutches laid. We found that the climatic conditions (SST) in the foraging grounds affected the population nesting phenology in the short term (i.e. within the same year); warmer years triggered an earlier onset of nesting. However, the effect of foraging grounds SST upon nesting is comparatively less important than the local conditions at the nesting ground. Although nesting phenology seems to depend on current''s year foraging grounds SST the number of nests in our study rookery were negatively correlated with SSTs recorded 2 years prior nesting, with higher SST leading to fewer nests. From this point of view, climate change at the foraging grounds may influence the reproductive phenology of loggerheads. [Copyright &y& Elsevier]

Abstract: Global climate change is likely to have an important influence on the phenology, behaviour and population dynamics of many species. We investigate climatic related changes in the breeding phenology of Mediterranean loggerhead marine turtles Caretta caretta over a 19 year period and the potential relationship between these changes and reproductive success and performance. We found that the studied population has experienced fluctuating sea surface temperatures (SST) with an increasing trend during the last century. With increasing spring SST there is a trend towards earlier nesting. However, there is no significant relationship between SST and nesting season, defined as the duration between the first recorded emergence and the last nest laid. Our analyses indicate that marine turtles display phenological changes, and thus maintain favorable thermal conditions at the nesting sites. Furthermore, increasing spring SST was correlated with decreasing clutch size and increasing hatching success that resulted in an apparent lack of correlation between SST and hatchling production. This apparent independence might be misleading since it only holds for a limited range of SST values. Thus, if we estimate the effect of climate change on loggerhead population growth as neutral, based on the apparent independence between SST and total number of hatchlings, we will be underestimating the population extinction risk. [Copyright &y& Elsevier]