De Levende Natuur nummer 1 van 2026 (English summary)

Rush vegetation can recover in the Rhine-Meuse estuary

Over the past few centuries, the area of freshwater tidal zones in Europe has shrunk considerably, and with it the associated rush vegetation. There are opportunities to restore these areas in the Rhine-Meuse estuary. The soil conditions appear to be partially suitable for the establishment of new rush species, but the availability of viable seeds is a major bottleneck. Emerging plants also have to deal with grazing, including by geese.

Reintroduction can help restore raised bogs

Valuable ecosystem services of raised bogs in the Netherlands have declined due to peat extraction and drainage. Although restoration efforts have locally promoted the development of floating rafts, hummock-forming Sphagnum species, essential for restoration of active peat formation, rarely established spontaneously. Reintroduction of these species may therefore be a promising restoration strategy. This study aimed to identify factors influencing 1) spontaneous hummock establishment and 2) growth of reintroduced hummock-forming Sphagnum in floating rafts. Hummocks occur under a wide range of local environmental conditions, indicating that colonization is slow and a probabilistic process. Reintroduction in floating rafts proved successful, though success varied strongly between sites. Sites with stable water levels (<40 cm fluctuation, also in dry years), large floating rafts on weakly humified (“white”) peat, and sufficient pore-water CO₂ concentrations (>750 μmol L⁻¹) appeared most suitable. We recommend evaluating these combined variables before reintroduction.

Meadow management and predation are key factors in survival of blacktailed godwits in South Holland

The province South Holland harbors 15 % of the Dutch breeding population of black-tailed godwit Limosa limosa, but numbers are declining. To reverse the decline, godwits are protected in nature reserves and in agricultural areas with agri-environmental schemes, which are managed for high grassland diversity, including partial flooding. However, reproductive success has remained low. We studied the impact of winter flooding and grassland management on reproductive success over four years in five study areas (agricultural polders Bergambacht and Vlist, and the reserves De Nesse, De Wilck and Westeinde). We measured hatching success, the number successful pairs successfully fledging chicks, grassland characteristics, habitat selection, spatial movements of broods, and predation pressure by common buzzards Buteo buteo. Clutch survival was high at 50-70%, but few pairs successfully raised broods. The reserve De Wilck, with the lowest breeding success, had a nesting buzzard that provided on average one wader chick per day to his brood. Godwit families stayed close to their nesting site. Families did not specifically select the commonly available grassland type with sparse herbs nor the few herb-rich grasslands, but they did select the uncommon grassland type with dense tall vegetation. Generally, they avoided short grass caused by long periods of winter flooding and grazing by herbivorous waterbirds. They raised chicks successfully in Polder de Vlist, which is dominated by production grasslands with late mowing schemes. The sharp declines in families in early May and the selection of grassland with dense tall vegetation that offered shelter suggest that predator avoidance played a role. We conclude that chick survival could improve with management for structured grasslands with tall vegetation alternated with shorter vegetation, providing cover against predation and food.