The fate of endozoochorously dispersed seeds

Endozoochory, or the dispersal of plant seeds via ingestion by vertebrate animals and the consecutive deposition of seeds in dung, is a widespread phenomenon in temperate grassland species. The first steps in this dispersal cycle have been extensively studied in recent decades while less is known about the next steps, or the post-dispersal fate of deposited seeds. In this PhD the germination, establishment, growth and flowering of temperate grassland species was experimentally assessed through dung addition and inter- and intraspecific competition experiments. Furthermore, the role of different functional groups of dung beetles in secondary seed dispersal and dung degradation has been studied in a large-scaled multi-site experiment in different climate and biogeographic zones in the Western Palaearctic

Ecological sustainability in rangelands : the contribution of dung beetles in secondary seed dispersal (case study: Chaharmahal and Bakhtiari province, Iran)

Ecological sustainability has been recognized as one of the main aspects of sustainable development of rangelands, at which different kinds of animal including insects, make substantial contributions. Dung beetles, known as dung-visiting insects, play several key roles in many ecological functions from which benefit both terrestrial ecosystems and human population. Specifically, they benefit rangelands through reducing greenhouse gas emission, nutrient cycling, plant growth enhancement, trophic regulation and pollination and secondary seed dispersal. This study examined secondary seed dispersal as one of the ecological functions of dung beetles, in Chaharmahal and Bakhtiari province, Iran. We applied an experimental approach to measure ecological function (i.e. seed removal) by functional groups of dung beetles. We tested whether functional dung beetle groups influence secondary seed dispersal differently. Through repeated standardized samples of sheep dung, data obtained regularly during two different months August and November in 2013. The results show that dung beetles play a role in secondary seed dispersal. However, it is affected by seed size, so that seed removal increased in the order of, large, medium and small size, respectively. The significant differences between treatments were found for small seeds in the both months. More seeds were dispersed from treatment t02 (all combinations of functional groups except large rollers) in August, while in November more seeds from treatments t01 (dwellers plus large and small tunnelers plus large and small rollers) and t03 (the combinations of dwellers plus small tunnelers, and small rollers) were removed. As a conclusion, it is suggested that if it is to guarantee the ecological sustainability of rangelands, paying attention to the ecological functions of dung beetles is crucial

Short-term impact of sheep grazing on salt-marsh vegetation succession in a newly created salt-marsh site

In this paper, the effect of three winter seasons of sheep grazing on cover, composition and species richness of vegetation, Elymus athericus expansion and forage quality of saltmarsh species were studied. Four zones were selected: three in real salt-marsh habitat (low, intermediate and high levels) and the fourth in the transition between salt-marsh and sand dune habitat. In each of the three salt-marsh zones, one site was selected and two sites were designated in the transitional zone. Half of each site was excluded from grazing (so-called exclosures) all year round, while the other half was accessible to sheep from mid-August until mid-June (enclosure areas). At each zone, 10 plots (2m × 2m) were established: five within exclosure and five within enclosure sites. In all plots, the cover of all species was estimated in the growing season in 2005 (initial state) and 2007 (state after two years of grazing). In addition, a total of 1516 quadrates (50cm × 50cm) were used to harvest the biomass of species to estimate the forage quality variation during the grazing period inside the plots. The forage quality variables were the percentages of crude protein, acid detergent fibre and neutral detergent fibre. The data of the cover of dominant salt-marsh species, species richness, total cover, plant composition and forage quality parameters are compared between exclosure and enclosure plots and between two sampling years (2005 and 2007) using repeated measurements (general linear model) separately for each zone. The results showed that after three years of plant succession, sheep grazing had a positive influence on plant richness on the high part of the salt-marsh, a negative effect in the transitional zone and no effect in the other zones. Grazing had no effect on cover and plant composition. Forage quality parameters were affected by sheep grazing only in the low salt-marsh zone. Limonium vulgare had the highest forage quality andElymus athericus had the lowest. It would appear that grazing with the current intensity and number of grazers would fail to hamper the expansion of Elymus athericus. A higher intensity of mixed sheep-cattle or cattle grazing would be needed to better control this highly prolific species

The need for aquatic tracking networks : the Permanent Belgian Acoustic Receiver Network

Abstract Aquatic biotelemetry techniques have proven to be valuable tools to generate knowledge on species behaviour, gather oceanographic data and help in assessing effects from anthropogenic disturbances. These data types support international policies and directives, needed for species and habitat conservation. As aquatic systems are highly interconnected and cross administrative borders, optimal data gathering should be organized on a large scale. This need triggered the development of regional, national and international aquatic animal tracking network initiatives around the globe. In Belgium, a national acoustic receiver network for fish tracking, called the Permanent Belgian Acoustic Receiver Network, was set up in 2014 with different research institutes collaborating. It is a permanent network with 160 acoustic receivers and since the start, over 800 animals from 16 different fish species have been tagged and generated more than 17 million detections so far. To handle all the (meta)data generated, a data management platform was built. The central database stores all the data and has an interactive web interface that allows the users to upload, manage and explore (meta)data. In addition, the database is linked to an R-shiny application to allow the user to visualize and download the detection data. The permanent tracking network is not only a collaborative platform for exchange of data, analysis tools, devices and knowledge. It also creates opportunities to perform feasibility studies and Ph.D. studies in a cost-efficient way. The Belgian tracking network is a first step towards a Pan-European aquatic tracking network

The need for aquatic tracking networks: the permanent Belgian Acoustic Receiver Network

Aquatic biotelemetry techniques have proven to be valuable tools to generate knowledge on species behaviour, gather oceanographic data and help in assessing effects from anthropogenic disturbances. These data types support international policies and directives, needed for species and habitat conservation. As aquatic systems are highly interconnected and cross administrative borders, optimal data gathering should be organized on a large scale. This need triggered the development of regional, national and international aquatic animal tracking network initiatives around the globe. In Belgium, a national acoustic receiver network for fish tracking, called the Permanent Belgian Acoustic Receiver Network, was set up in 2014 with different research institutes collaborating. It is a permanent network with 160 acoustic receivers and since the start, over 800 animals from 16 different fish species have been tagged and generated more than 17 million detections so far. To handle all the (meta)data generated, a data management platform was built. The central database stores all the data and has an interactive web interface that allows the users to upload, manage and explore (meta)data. In addition, the database is linked to an R-shiny application to allow the user to visualize and download the detection data. The permanent tracking network is not only a collaborative platform for exchange of data, analysis tools, devices and knowledge. It also creates opportunities to perform feasibility studies and Ph.D. studies in a cost-efficient way. The Belgian tracking network is a first step towards a Pan-European aquatic tracking network

Trophic ecology of the european eel (Anguilla anguilla) across different salinity habitats inferred from fatty acid and stable isotope analysis

We combined fatty acid (FA) and stable isotope (SI) analyses to investigate the trophic ecology of different stages of European eels (Anguilla anguilla) across seawater (SW), brackish water (BW), and freshwater (FW) habitats. Salinity was the main driver of differences in the biochemical composition, and the greatest variation occurred between SW and FW eels. SW eels had a higher content of the FA indicator of carnivory, as well as the highest stable isotope ratios (C, N). In contrast, FW eels exhibited the highest lipid content and omega-6 polyunsaturated FA, but the lowest stable isotope ratios, suggesting major dietary differences between the eels in these two habitats. While the biochemical composition of BW eels was closer to those of SW eels, BW eels had the largest SI range, indicating higher dietary plasticity. FW individuals had better overall condition compared to SW eels. Independent of habitat, larger individuals were in the best condition, and had higher lipid content and monounsaturated FA. These findings suggest a biological advantage for eels to maintain a catadromous life history strategy.publishedVersio

Developing positive attitude towards science and mathematics through motivational classroom experiences

This paper presents results of a survey among school children aged 10 to 14 years, who participated in science or mathematics workshops. It particularly relates to their interest and motivation determined immediately after the workshop had finished. A total of 70 workshops were held in elementary schools of Rijeka, Croatia, involving the participation of 1240 students aged from 10 to 14 years. The workshops were designed in order to encourage active engagement in class work and a deeper approach to learning stemming from meaningful involvement in a real problem related to everyday life. The results of the survey on student’s attitudes towards science and mathematics after the workshop indicated that students accept this type of lesson eagerly, they value demonstrations, applications and practical, hands-on experimentation, and that after this type of classroom activity they express positive attitude towards science and mathematics

Developing positive attitude towards science and mathematics through motivational classroom experiences

This paper presents results of a survey among school children aged 10 to 14 years, who participated in science or mathematics workshops. It particularly relates to their interest and motivation determined immediately after the workshop had finished. A total of 70 workshops were held in elementary schools of Rijeka, Croatia, involving the participation of 1240 students aged from 10 to 14 years. The workshops were designed in order to encourage active engagement in class work and a deeper approach to learning stemming from meaningful involvement in a real problem related to everyday life. The results of the survey on student’s attitudes towards science and mathematics after the workshop indicated that students accept this type of lesson eagerly, they value demonstrations, applications and practical, hands-on experimentation, and that after this type of classroom activity they express positive attitude towards science and mathematics

Gps tracking data of western marsh harriers breeding in belgium and the Netherlands

In this data paper three datasets are described containing GPS tracking and acceleration data of Western marsh harriers (Circus aeruginosus) breeding in Belgium and the Netherlands. The Western marsh harrier is included as a threatened bird species in Annex I of the European Bird Directive due to the steep decline in population densities. In order to collect data of habitat use and migration behaviour, Western marsh harriers were equipped with light-weight solar powered GPS trackers developed by the Institute for Biodiversity and Ecosystem Dynamics (IBED) at the University of Amsterdam (University of Amsterdam Bird Tracking System, UvA-BiTS). These trackers automatically collect and store data on the bird’s activity and 3D position in time and transmit these data to ground stations. The datasets were collected by the Research Institute for Nature and Forest (INBO) and the Dutch Montagu’s Harrier Foundation. Tracked Western marsh harriers were breeding in the northeast of the Dutch province of Groningen and on the opposite side of the river Ems in Germany (H_GRONINGEN), in the region of Waterland-Oudeman near the Belgian-Dutch border (MH_WATERLAND), and at the left bank of the Scheldt estuary, close to the Belgian-Dutch border and north of the city of Antwerp (MH_ANTWERPEN). Most individuals remained within 10 km from their nesting sites during the breeding season and wintered in West Africa. H_GRONINGEN contains 987,493 GPS fixes and 3,853,859 acceleration records of four individuals since 2012. MH_WATERLAND contains 377,910 GPS fixes of seven individuals. Sampling in this region began in 2013. Three more Western marsh harriers were tagged in the Scheldt estuary near Antwerp more recently in 2018 (one individual) and 2019 (two individuals) for the MH_ANTWERPEN study, which contains 47,917 GPS fixes and 227,746 acceleration records. The three Western marsh harrier datasets were published as separate studies in Movebank (https://www. movebank.org) and archived as data packages in Zenodo (https://www.zenodo.org) to ensure long-term preservation and versioning of the data