DNA diet profiles with high‐resolution animal tracking data reveal levels of prey selection relative to habitat choice in a crepuscular insectivorous bird

Given the global decline of many invertebrate food resources, it is fundamental to understand the dietary requirements of insectivores. We give new insights into the functional relationship between the spatial habitat use, food availability, and diet of a crepuscular aerial insectivore, the European Nightjar (Caprimulgus europaeus) by relating spatial use data with high‐throughput sequencing (HTS) combined with DNA metabarcoding. Our study supports the predictions that nightjars collect a substantial part of their daily nourishment from foraging locations, sometimes at considerable distance from nesting sites. Lepidopterans comprise 65% of nightjars' food source. Nightjars tend to select larger species of Lepidoptera (>19 mm) which suggests that nightjars optimize the efficiency of foraging trips by selecting the most energetically favorable—larger—prey items. We anticipate that our findings may shed additional light on the interactions between invertebrate communities and higher trophic levels, which is required to understand the repercussions of changing food resources on individual‐ and population‐level processes

Food web uncertainties influence predictions of climate change effects on soil carbon sequestration in heathlands

Carbon cycling models consider soil carbon sequestration a key process for climate change mitigation. However, these models mostly focus on abiotic soil processes and, despite its recognized critical mechanistic role, do not explicitly include interacting soil organisms. Here, we use a literature study to show that even a relatively simple soil community (heathland soils) contains large uncertainties in temporal and spatial food web structure. Next, we used a Lotka–Volterra-based food web model to demonstrate that, due to these uncertainties, climate change can either increase or decrease soil carbon sequestration to varying extents. Both the strength and direction of changes strongly depend on (1) the main consumer’s (enchytraeid worms) feeding preferences and (2) whether decomposers (fungi) or enchytraeid worms are more sensitive to stress. Hence, even for a soil community with a few dominant functional groups and a simulation model with a few parameters, filling these knowledge gaps is a critical first step towards the explicit integration of soil food web dynamics into carbon cycling models in order to better assess the role soils play in climate change mitigation

Multi-scale habitat selection throughout the annual cycle of a long-distance avian migrant

Long-distance migrants are constrained by widely separated hospitable habitats in geographically isolated locations, making them vulnerable to environmental change, both through natural and anthropogenic causes. Knowledge about their resource selection decisions is imperative to understand the drivers of their declines. The distinct periods within an annual cycle, when individuals experience different environmental circumstances, are inextricably linked through carry-over effects which can have important consequences for the individual, and consequently the population. In this study, we employ precise archival GPS-tracking data of European Nightjars (Caprimulgus europaeus) and high-resolution global land cover data to examine habitat selection during the sedentary wintering and breeding periods, as well as during autumn and spring migration, using a correlational approach. We demonstrate how nightjars use general habitat characteristics, such as landscape diversity, for high-order habitat selection, while resource selection at a finer spatial scale is reliant on fine-scale variables related to a habitat’s suitability, such as surface area of grassland and shrubland. We show that nightjars favour spatially diverse landscapes, which allows them to minimize time spent searching for optimal habitats. The considerable variation in the drivers of habitat selection between and within seasons shows how anthropogenic land-use change can have an array of different impacts on migrants by influencing large- and fine-scale habitat selection. This study shows the advantages of an individual based GPS-tracking approach, combined with high spatial resolution remote sensing data, and highlights the need for full annual-cycle research on scale dependent habitat selection of long-distance avian migrants

The Use of Static Magnetic Field on Irrigation Water and Its Effect on Mineral and Nutrient Content in <em>Solanum lycopersicum</em> L.

Solanum lycopersicum L. is a nutraceutical plant. Tomato yield and morphological features have been improved by irrigation with water treated with static magnetic field (SMF). The effect of magnetically treated water with SMF (20–200 mT) on mineral and nutritional contents in Solanum lycopersicum L. was investigated. Bromatological analyses and minerals contents were determined in tomato fruits harvested after the application of two irrigation protocols (water treated with SMF between 20 and 200 mT and water without SMF treatment as control). Fruits were selected for analysis according to a completely randomized design. Although no significant differences were observed between both groups with regard to bromatological analyses (moisture, total ash, total solids, proteins), an increasing trend was determined for these components in fruits of plants irrigated with SMF-treated water. An increase was detected for potassium (K), calcium (Ca) and cupper (Cu) concentrations in these conditions as compared to fruits of control plants. The SMF treatment of irrigation water improves the nutrient uptake and the water use efficiency in tomato. The nutraceutical value of these fruits was increase and can be considered as an important strategy for future crop production to improve food quality

Magnetically treated water on phytochemical compounds of Rosmarinus officinalis L.

Irrigation using water treated with static magnetic field (SMF) has recently been used as a strategy to stimulate the growth and development of different plant species. The aim of this study was to characterize the bioactive compounds and evaluate the anatomical structure of Rosmarinus officinalis L. irrigated with SMF-treated water. Results demonstrate that the treatment promoted plant growth, the number of trichomes and increased concentrations of secondary metabolites. Methanol-extracted leaves revealed that rosmarinic acid was detected in both experimental groups, without a difference in the level. Camphor, α-terpineol and verbenone were determined as the most abundant compounds present in these leaf extracts and were strongly increased in plants irrigated with SMF-treated water. Similar results were also observed for endo-borneol, bornyl acetate and β-amyrin concentrations.Taken together, these results indicate that irrigation with SMF-treated water can be used to improve the production of rosemary to obtain pharmaceutical products with an increased antioxidative activity

Meta-analysis of multidecadal biodiversity trends in Europe

Local biodiversity trends over time are likely to be decoupled from global trends, as local processes may compensate or counteract global change. We analyze 161 long-term biological time series (15-91 years) collected across Europe, using a comprehensive dataset comprising similar to 6,200 marine, freshwater and terrestrial taxa. We test whether (i) local long-term biodiversity trends are consistent among biogeoregions, realms and taxonomic groups, and (ii) changes in biodiversity correlate with regional climate and local conditions. Our results reveal that local trends of abundance, richness and diversity differ among biogeoregions, realms and taxonomic groups, demonstrating that biodiversity changes at local scale are often complex and cannot be easily generalized. However, we find increases in richness and abundance with increasing temperature and naturalness as well as a clear spatial pattern in changes in community composition (i.e. temporal taxonomic turnover) in most biogeoregions of Northern and Eastern Europe. The global biodiversity decline might conceal complex local and group-specific trends. Here the authors report a quantitative synthesis of longterm biodiversity trends across Europe, showing how, despite overall increase in biodiversity metric and stability in abundance, trends differ between regions, ecosystem types, and taxa.peerReviewe

Mammal responses to global changes in human activity vary by trophic group and landscape

Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human–wildlife interactions along gradients of human influence.Peer reviewe

COMPARATIVE STUDY OF THREE TRANSECT METHODS TO ASSESS CORAL 29 Comparative Study of Three Transect Methods to Assess Coral Cover, Richness and Diversity

Abstract-Three different transect methods were compared at two different sites in Kenya, on their efficiency to estimate hard coral cover, genus richness and Shannon diversity index. For a modified line transect method (LTM), the line intercept method (LIT) and a linear point intercept (LPI) method the relative efficiency of the three methods was calculated with respect to the tested parameters. The three methods were examined along identical transect lines (10 m) and a total of 27 transect triplets were recorded in Vipingo and 21 in Mombasa. The correlation coefficients for all three ecological parameters were calculated for the three possible pairs of methods, and the accumulation curves plotted for each of the parameters using number of transects as the independent variable. Results from the three methods were virtually indistinguishable. When the parameters were plotted using measuring time on the x axis, the curves for the LPI method converged twice as fast as those for LTM, while LIT time was intermediate. It is suggested that the LPI method might be most suitable for assessing coral cover, richness and diversity where time and effort are significant constraints

Simulation-based assessment of the performance of hierarchical abundance estimators for camera trap surveys of unmarked species

Abstract Knowledge on animal abundances is essential in ecology, but is complicated by low detectability of many species. This has led to a widespread use of hierarchical models (HMs) for species abundance, which are also commonly applied in the context of nature areas studied by camera traps (CTs). However, the best choice among these models is unclear, particularly based on how they perform in the face of complicating features of realistic populations, including: movements relative to sites, multiple detections of unmarked individuals within a single survey, and low detectability. We conducted a simulation-based comparison of three HMs (Royle-Nichols, binomial N-mixture and Poisson N-mixture model) by generating groups of unmarked individuals moving according to a bivariate Ornstein–Uhlenbeck process, monitored by CTs. Under a range of simulated scenarios, none of the HMs consistently yielded accurate abundances. Yet, the Poisson N-mixture model performed well when animals did move across sites, despite accidental double counting of individuals. Absolute abundances were better captured by Royle-Nichols and Poisson N-mixture models, while a binomial N-mixture model better estimated the actual number of individuals that used a site. The best performance of all HMs was observed when estimating relative trends in abundance, which were captured with similar accuracy across these models