Weather, pollen, and masting – new paper in Ecology!

Our recent Ecology paper on system-specific roles of weather and pollination dynamics in driving seed production in European trees is now available online!

In wind-pollinated trees, weather and seed production can mechanistically link through flowering and pollination dynamics in different ways. According to pollen coupling hypothesis, flowering effort of trees is driven by weather and plant resources, which directly translates into the size of seed crop through efficient pollination. In contrast, weather can affect pollination efficiency, leading to occasional high seed crops – this is so-called pollination Moran effect hypothesis. Furthermore, Moran effects can arise because of weather effects on flowering synchrony, which, in turn, drives pollination efficiency (phenology synchrony hypothesis).

Using a 19-year data set from three sites in Poland, we investigated the relationship between weather, airborn pollen, and seed production in two oak species (Quercus petraea and Q. robur) and beech (Fagus sylvatica). We found that for oaks and beech, the warm summers preceding flowering correlated with high pollen abundance and warm springs resulted in high flowering synchrony (short pollen seasons). However, in beech the best predictor of seed crops was pollen abundance, supporting the pollen coupling hypothesis. In contrast, large seed crops in oaks correlated with short pollen seasons, thus supporting the pollination Moran effect and phenology synchrony hypotheses. These findings suggest that fundamentally different proximate mechanisms may drive masting in oaks and beech.

You can read the paper here and on ResearchGate. Read also what Michał Bogdziewicz, the leading author, wrote about this study on his page.


Sessile oak (Quercus petraea) © Jakub Szymkowiak



Wood warbler field season 2017 is over!

After 3 months of intense field work, I have finished this year’s field season. It was a final-year of an experiment testing how wood warblers make settlement decisions in a temporally varying landscape of fear. The data look very promising, so stay tuned! Below you can find some photos of wood warblers I took this year.

In the meantime, I was working with Michał Bogdziewicz on mechanisms of mast-seeding in European trees. We have some really cool results to share, but more on this when the paper will show up online, which should be soon!



Field season 2017 is on!

Since the early April, my field season 2017 has started and now I spend most of the time enjoying the field work. In this year, I continue studying how wood warblers make settlement decisions in a landscape of fear. I also continue collecting data on nest predation in wood warblers, as well as prepare for some really exciting experiments planned for the next year!

In the meantime, I work with Michał Bogdziewicz on several aspects of ecology of mast-seeding in trees. We have some really cool results to show – more on this soon!


© Jakub Szymkowiak


© Jakub Szymkowiak