Jaarverslag 2022
“On the way to Godwit-proof…”
De staat van ons landschap:
Biomonitoring van duurzame
landbouw innovatie
De landbouw in Nederland staat voor een grote uitdaging: het produceren van genoeg, veilig en gezond voedsel zonder dat dit ten koste gaat van de leefbaarheid op het platteland voor plant, mens en dier. En zonder dat het de planeet in bredere zin zwaar belast. Een veelgehoorde en serieuze oplossingsrichting is om het bedrijfsmodel weer te baseren op korte kringlopen en natuurlijke processen in bodem, water en lucht. Dit heeft de potentie om de grote druk op biodiversiteit, landschap, milieu, klimaat en gezondheid te verlichten. De grutto is als boerenlandvogel in staat om ons te laten zien of dat lukt. We verwachten dat een stabiele aanwezigheid van grutto’s, of nog beter populatiegroei, wijst op een hoge biodiversiteit, een gebalanceerd voedselweb en bodems die horen bij een duurzame melkveehouderij in een aantrekkelijk landschap.
En mar et avril 2022 nous sommes allés au Banc d’Arguin pour attraper des bécasseaux maubèches pour la recherche par satellite. L’objectif était d’équiper bécasseaux maubèches avec des émetteurs satellites afin de suivre leurs routes de migration et leur synchronisation vers la mer des Wadden et les zones de reproduction Sibériennes. Nous avons réussi à capturer des oiseaux pour le marquage et nous avons également capturé un bon nombre d’oiseaux pour la recherche à long terme sur les bécasseaux maubèches et les barges rousse.
Post-war intensification of agriculture has extensively modified the countryside of Europe, transforming most semi-natural
grassland habitats into homogeneous fields, characterized by mechanization, deep drainage and the increasing use of artificial fertilizers and agrochemicals (Benton et al., 2003; Emmerson et al., 2016), and unfavourable to farmland birds that require varied habitat structures for breeding, refugia and food resources (Donald et al., 2001; Newton, 2004, 2017; Stoate et al., 2009). The diversity and abundance of insects, the main food of farmland birds during the breeding season, are significantly lower in high-intensity farmland compared to low-intensity farmland (Seibold et al., 2019). Moreover, intensive agricultural practices contribute to soil degradation by lowering groundwater tables and mechanically injecting manure, which intensifies soil desiccation and results in a hard top soil layer impenetrable for soil probing birds (Gilroy et al., 2008; Onrust & Piersma, 2019; Onrust, Wymenga, Piersma, et al., 2019). Furthermore, frequent mechanical mowing coinciding with the birds’ breeding season reduces the reproductive success of farmland birds (Kentie et al., 2015; Kleijn et al., 2010; Kruk et al., 1997; Roodbergen & Teunissen, 2019).
Grasslands that remain intact for many years become more naturally valuable for every year they are left untouched. These permanent grasslands are more valuable for biodiversity than grasslands plowed over every so often to make new grass or arable crops, Taylor Craft and colleagues at the University of Groningen reported in the scientific journal Frontiers. “From worms to black-tailed godwits, lots of organisms benefit from old grassland,” Craft says. “But the registration of these old grasslands in official records leaves quite a bit to be desired.”
Of all the fields used for agriculture in the Netherlands, the majority are used for feeding cows that produce milk. These fields are also home to many species of plants and animals that provide important ecosystem services such as nutrient cycling, pest control, seed dispersal, and climate regulation. In the Netherlands, one of the most intensively farmed countries in the world, little land is left for wildlife, so it is important for scientists to learn how our farmed land can also be used to give wildlife a home. In a recent study, a team of ecologists from the University of Groningen mapped agricultural grasslands within the municipality of Southwest Friesland, the most important breeding area for the Black-tailed Godwit. This map depicts not only grasslands but also shows how often each field has been used to grow annual row crops, such as maize or wheat. By keeping track of this, the researchers were able to measure how often grasslands are replaced by other crops. This indicates the stability in the use of grasslands and the conditions for the species that live there.
Read the open access article at: https://www.frontiersin.org/articles/10.3389/fenvs.2022.982925/full
In this expedition from 1 to 26 February 2022 we visited the most important areas for Black-tailed Godwits in southern Spain and Portugal during northward migration. Our aim was to resight individual colour marked birds, describe the habitats godwits used and to gain information on threats and opportunities by field observations and meetings with local experts. In this report we present a daily overview of our findings with photos, locations we visited, numbers present and the first conclusions and recommendations.
In this expedition from 3 to 13 October 2022 we visited the most important areas for wintering Black-tailed Godwits in southern Spain. Our aim was to resight individual colour marked birds, describe the habitats used by godwits and to gain information on threats and opportunities by field observations and meetings with local experts. In this report we present a daily overview of our findings with photos, locations we visited, numbers present and the first conclusions and recommendations.
We describe a vocal signal and associated postures shown by Eurasian Spoonbills Platalea leucorodia leucorodia just before the departure of (part of) the flock from a site, but also occurring in flight. Onomatopoetically called ‘ook’, it is a soft muffled sound that was noticed in Spoonbills at a stopover site during southward migration in southwestern France and at a post-breeding feeding site in The Netherlands. When making the ‘ook’-sounds, adults as well as juveniles contributed to what looked like dialogues, the sound of the juvenile having a higher pitch than that of the adult. On the basis of their specific occurrence in
pre-departure contexts, we propose that the vocalizations function during collective decision-making, perhaps contributing to reach consensus before and during non-routine group movements from one place to another.
We analyzed the food composition of 47 regurgitations and 11 stomach contents from nestling Eur- asian Spoonbills (Platalea leucorodia) in the colony of the estuary of the Odiel River (southwestern Spain). With a single exception, all prey consumed by nestlings were saltwater aquatic animals. Fish, particularly killifish (Fundulus spp.), were the most common and abundant component of the diet, accounting for 71% of the prey items. Prawns (Palaemonidae) appeared in half the food samples and accounted for 19% of the prey items. Relative abundance of potential prey at foraging habitats and in the diet suggests that fish were preferred over other prey types. The mean body length of the fish found in the food sample was greater than that at foraging habitats.
De staat van ons landschap: biomonitoring van duurzame landbouw innovaties
De landbouw in Nederland staat voor een grote uitdaging: het produceren van genoeg, veilig en gezond voedsel zonder dat dit ten koste gaat van de leefbaarheid op het platteland voor plant, mens en dier. En zonder dat het de planeet in bredere zin zwaar belast. Een veelgehoorde en serieuze oplossingsrichting is om het bedrijfsmodel weer te baseren op korte kringlopen en natuurlijke processen in bodem, water en lucht. Dit heeft de potentie om de grote druk op biodiversiteit, landschap, milieu, klimaat en gezondheid te verlichten. De grutto is als boerenlandvogel in staat om ons te laten zien of dat lukt. We verwachten dat een stabiele aanwezigheid van grutto’s, of nog beter populatiegroei, wijst op een hoge biodiversiteit, een gebalanceerd voedselweb en bodems die horen bij een duurzame melkveehouderij in een aantrekkelijk landschap.