Summary1. Climate change encompasses changes in both the means and the extremes of climatic variables, but the population consequences of the latter are intrinsically difficult to study. 2. We investigated whether the frequency, magnitude and timing of rare but catastrophic flooding events have changed over time in Europe's largest estuary. Subsequently, we quantified how this has affected the flooding risk of six saltmarsh nesting bird species. 3. We show that maximum high tide has increased twice as fast as mean high tide over the past four decades (0AE8 vs. 0AE4 cm year )1 ), resulting in more frequent and more catastrophic flooding of nests, especially around the time when most eggs have just hatched. 4. Using data on species' nest elevations, on their timing of egg-laying and on the duration that their eggs and chicks are at risk from flooding, we show that flooding risks increased for all six studied species (even after accounting for compensatory land accretion) and this is expected to worsen in the near future if they do not adapt. Moreover, our study provides the first evidence that increasing flooding risks have reduced the reproductive output below stable population levels in at least one species, the Eurasian oystercatcher Haematopus ostralegus. 5. Sensitivity analyses show that currently birds would benefit most from adapting their nest-site selection to higher areas. However, historically the lower marsh has been favoured for its proximity to the feeding grounds and for its low vegetation aiding predator detection. 6. Synthesis and applications. We argue that it is more difficult for birds to infer that habitat quality has decreased from changes in the frequency of rare and unpredictable extreme events than from trends in climatic means. Consequently, at present the lower parts of the saltmarsh may function as an ecological trap. The creation of new (i.e. low) saltmarshes -currently a restoration prioritymay thus counteract the goal of increasing the avian biodiversity of an area. Management tools to mitigate the effects of climate change, either by making the higher saltmarsh more attractive (mowing, predator control) or by reducing the flooding risk of the lower marsh (building elevated plots), await to be tested.

Correlations among plant traits often reflect important trade‐offs or allometric relationships in biological functions like carbon gain, support, water uptake, and reproduction that are associated with different plant organs. Whether trait correlations can be aggregated to “spectra” or “leading dimensions,” whether these dimensions are consistent across plant organs, spatial scale, and growth forms are still open questions. To illustrate the current state of knowledge, we constructed a network of published trait correlations associated with the “leaf economics spectrum,” “biomass allocation dimension,” “seed dimension,” and carbon and nitrogen concentrations. This literature‐based network was compared to a network based on a dataset of 23 traits from 2,530 individuals of 126 plant species from 381 plots in Northwest Europe. The observed network comprised more significant correlations than the literature‐based network. Network centrality measures showed that size traits such as the mass of leaf, stem, below‐ground, and reproductive tissues and plant height were the most central traits in the network, confirming the importance of allometric relationships in herbaceous plants. Stem mass and stem‐specific length were “hub” traits correlated with most traits. Environmental selection of hub traits may affect the whole phenotype. In contrast to the literature‐based network, SLA and leaf N were of minor importance. Based on cluster analysis and subsequent PCAs of the resulting trait clusters, we found a “size” module, a “seed” module, two modules representing C and N concentrations in plant organs, and a “partitioning” module representing organ mass fractions. A module representing the plant economics spectrum did not emerge. Synthesis. Although we found support for several trait dimensions, the observed trait network deviated significantly from current knowledge, suggesting that previous studies have overlooked trait coordination at the whole‐plant level. Furthermore, network analysis suggests that stem traits have a stronger regulatory role in herbaceous plants than leaf traits.

The cost of reproductive effort is known to result in a trade-off between current and future reproduction. Similarly, trade-offs in energy allocation may occur between components of reproductive effort, mating and parental effort, within a single reproductive episode. We investigated the energy allocated to mating effort (calling to attract females) and parental effort (donation of spermatophore nutrients at mating) by male bushcrickets, Requena verticalis, under two dietary regimes. Males provided with a low quality diet reduced the daily energy allocated to calling activity while maintaining their investment in spermatophores. Males provided with a high quality diet did not allocate more resources per day to their spermatophores but stored excess energy for future reproduction. Thus, on a per day basis, males appear to hold constant their investment in the spermatophore at the cost of reduced mating effort when resources are limited. Males on both diets, however, increased the size of their spermatophore donations when the interval between female encounters was increased. One explanation for this pattern could be a frequency-dependent optimization of spermatophore size.

Land management in coastal areas has to cope with impacts of climate change and sea level rise. In Germany, landscape plans assess and organize the spatial allocation of land use as an environmental contribution to general spatial planning. Collaborative planning processes are important to develop sustainable and ecosystem-based strategies to make coastal landscapes climate proof. However, there is little experience with collaborative processes in practical planning in Germany, and probably in other countries as well. This paper conducts an empirical case study in the low-lying coastal areas of northwest Germany. During a collaborative landscape planning process, four different ecosystem-based land management scenarios have been co-designed by regional experts and researchers. The participatory and iterative process included the development of scenario narratives to define planning goals, the use of land use elements and their relations to ecosystem services as planning entities in terms of indicators, the art-based illustrations of the different scenarios, and an evaluation and monitoring of the outcomes by regional experts. The decision-maker group decided on the so-called "actor-based" scenario, which contained freshwater retention areas (polders) to prevent potential uncontrolled flooding of the hinterland. This climate adaptation strategy has been implemented in the regional development plan of the county.

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