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When waders gather in mixed‐species flocks to feed on benthic prey, differences in morphological traits, foraging strategies and prey selection may allow different species to optimize their energy intake while reducing competition. As the effect of the fine‐scale spatial distribution of resources on energy intake is unknown, we simulated the foraging performance of two types of waders with contrasting body plans and foraging strategies in a variety of virtual mudflats with different horizontal and vertical prey distribution patterns. Although larger, longer‐billed individuals had higher energy intake rates, smaller individuals with shorter bills maintained higher prey capture rates by relocating if prey was insufficiently available. Shorter‐billed individuals struggled more to meet their energetic demands because they selected smaller prey items and had a more limited capacity to metabolize energy from food. Being able to catch larger, high‐quality prey offered a competitive advantage for longer‐billed individuals, which could be a driving force for the evolutionary lengthening of bills in waders. Interestingly, their performance was more affected by the horizontal than by the vertical prey distribution. Quantifying prey distributions may help explain how some wader species can co‐occur in the field and why some wetland areas are unattractive as foraging areas. The work confirms that the foraging performance of larger, longer‐billed birds is not limited by bill size per se, but by the energetic trade‐offs associated with the ability to catch larger prey items more efficiently, increased handling times and higher absolute energy costs. These trade‐offs may become particularly important in landscapes where prey is scarce and spatially patchy. [ABSTRACT FROM AUTHOR]

Latitudinal range limits for mangroves on high‐energy, wave‐dominated coasts are controlled by geomorphological features and estuarine dynamics. Mangroves reach a southern global range limit along the South African coastline, but the distribution is patchy, with stands occurring in only 16% of the estuaries in the region. Yet, the persistence of forests planted >50 years ago beyond the natural distribution limit suggests that additional estuaries could support mangroves. Understanding regional drivers is necessary to inform global‐scale estimates for how this important ecosystem is predicted to respond to climate change.Here, we combine species distribution modelling (MaxEnt), Lagrangian particle tracking using an eddy‐ and tide‐resolving numerical ocean model, and connectivity matrices, to identify suitable mangrove habitats along the South African coastline at present, as well as under the IPCC RCP4.5 and RCP8.5 climate scenarios.Within the current South African distribution range (±900 km), eight more estuaries were identified to be suitable under contemporary conditions. When considering potential range extension (±110 km), an additional 14 suitable estuaries were identified. Connectivity matrices suggest limited long‐distance dispersal, stranding mostly at or near the release location, and a decreased probability of connectivity towards the range limit. Under both future climate scenarios, 30% of estuaries currently supporting mangroves are predicted to become unsuitable, while an additional six estuaries beyond the current distribution are predicted to become suitable. However, there is limited connectivity between these new sites and established forests.Synthesis. This study shows that dispersal substantially limits mangrove distribution at the southern African range limit and highlights the importance of including this process in species distribution models. Ultimately, our results provide new insight into mangrove conservation and management at range limits that are not controlled predominantly by temperature, as it has been assumed that mangroves will largely expand to higher latitudes under climate change. [ABSTRACT FROM AUTHOR]

Coastal salt- and brackish water lagoons are unique shallow habitats characterized by beds of submerged seagrasses and salt-tolerant Ruppia species. Established longterm and large-scale patterns of connectivity in lagoon systems can be strongly determined by patterns of nearshore and coastal currents next to local bird-mediated seed dispersal. Despite the importance of dispersal in landscape ecology, characterizing patterns of connectivity remains challenging in aquatic systems. Here, we aimed at inferring connectivity distances of Ruppia cirrhosa along European coastal lagoons using a population genetic imprint and modeled dispersal trajectories using an eddyresolving numerical ocean model that includes tidal forcing. We investigated 1,303 individuals of 46 populations alongside subbasins of the Mediterranean (Balearic, Tyrrhenian, Ionian) and the Atlantic to Baltic Sea coastline over maximum distances of 563-2,684 km. Ten microsatellite loci under an autotetraploid condition revealed a mixed sexual and vegetative reproduction mode. A pairwise FST permutation test of populations revealed high levels of historical connectivity only for distance classes up to 104-280 km. Since full range analysis was not fully explanatory, we assessed connectivity in more detail at coastline and subbasin level using four approaches. Firstly, a regression over restricted geographical distances (300 km) was done though remained comparable to full range analysis. Secondly, piecewise linear regression analyses yielded much better explained variance but the obtained breakpoints were shifted toward greater geographical distances due to a flat slope of regression lines that most likely reflect genetic drift. Thirdly, classification and regression tree analyses revealed threshold values of 47-179 km. Finally, simulated ocean surface dispersal trajectories for propagules with floating periods of 1-4 weeks, were congruent with inferred distances, a spatial Bayesian admixed gene pool clustering and a barrier detection method. A kinship based spatial autocorrelation showed a contemporary within-lagoon connectivity up to 20 km. Our findings indicate that strong differentiation or admixtures shaped historical connectivity and that a pre- and post LGM genetic imprint of R. cirrhosa along the European coasts was maintained from their occurrence in primary habitats. Additionally, this study demonstrates the importance of unraveling thresholds of genetic breaks in combination with ocean dispersal modeling to infer patterns of connectivity. [ABSTRACT FROM AUTHOR]

The Ganges Delta and Sundarbans comprise the largest continuous mangrove area in the world. These mangroves are subjected to high riverine and tidal dynamics, and the coastline irregularity is characterized by many north-to-south oriented rivers that may hamper dispersal of mangrove propagules. Whereas connectivity levels and resulting population genetic structure often can be explained by ocean currents, other factors may control estuarine-scale mangrove genetic patterns and limit gene flow even between sites in close geographic proximity. We investigated whether the complex estuarine coastline in the Ganges Delta and Sundarbans shaped the genetic structure of Avicennia officinalis populations across regions and rivers at various distances (ca. 1 to 265 km). Using nine microsatellite loci, 433 individuals from 14 populations revealed predominant outcrossing and a high level of genetic variation when compared to other Avicennia species. A moderate but significant level of differentiation was detected among populations (FST = 0.09), and a principal coordinate analysis clearly separated populations of the Chittagong coastline from the Sundarbans. An individual-based Bayesian analysis also indicated those two gene pools. Genetic distances across the whole region could best be explained by cumulative river width and geographical distance separating the populations. Within the Sundarban region, the low genetic differentiation of A. officinalis populations indicated a continuous distribution model with a smooth isolation-by-distance that gradually increased across large rivers shaping the genetic structure of A. officinalis in the Ganges Delta. These findings indicated that in addition to geographical distance, rivers might act as physical barriers, affect gene flow and shape genetic connectivity. This and detailed population genetic information should be incorporated into the ongoing afforestation or restoration strategies in and outside of the Sundarbans mangrove forest. [ABSTRACT FROM AUTHOR]

Artists and scientists alike came across unfamiliar landscapes and strikingly strange fauna and flora when they embarked for the ‘colonies’. In the 17thand 18thcenturies curiosity for the exotic developed into direct scientific observation, which is often still appreciated scientifically today, such as in biological taxonomy. Often observation, interpretation and reporting were geared towards functional aspects, a resourcist view on the environment in the wake of the colonial enterprise. This entailed that focus could be biased towards aspects of mercantile, political or strategic interest. Landscape vision is no exception for the possible biases. The Dutch painter Frans Post during his 7 year stay in the New World (Brazil) in the 17thcentury was the first to depict mangroves as a very characteristic tropical vegetation, unfamiliar to Europeans, in spite of its limited interest in the context of colonial economy. He did this in the strong and developing tradition of Dutch landscape painting. [ABSTRACT FROM PUBLISHER]