ABSTRACT
The ongoing depletion of natural systems and associated biodiversity decline is of growing international concern. Climate change is expected to exacerbate anthropogenic impacts on wild populations. The scale of impact on ecosystems and ecosystem services will be determined by the impact on a multitude of species and functional groups, which due to their biology and numbers are difficult to monitor. The IPCC has argued that surveillance or monitoring is critical and proposed that monitoring systems should be developed, which not only track developments but also function as "early warning systems." Human populations are already generating large continuous datasets on multiple taxonomic groups through internet searches. These time series could in principle add substantially to current monitoring if they reflect true changes in the natural world. We here examined whether information on internet search frequencies delivered by the Danish population and captured by Google Trends (GT) appropriately informs on population trends in 106 common Danish bird species. We compared the internet search activity with independent equivalent population trend assessments from the Danish Ornithological Society (BirdLife Denmark/DOF). We find a fair concordance between the GT trends and the assessments by DOF. A substantial agreement can be obtained by omitting species without clear temporal trends. Our findings suggest that population trend proxies from internet search frequencies can be used to supplement existing wildlife population monitoring and to ask questions about an array of ecological phenomena, which potentially can be integrated into an early warning system for biodiversity under climate change.
Subject(s)
Ecosystem , Search Engine , Animals , Humans , Big Data , Environmental Monitoring , Birds , DenmarkABSTRACT
Thrips are a major pest in protected strawberry production. Knowledge of thrips species composition could be instrumental for improved thrips management, but very little is known about which species are present in strawberries grown in high-tunnels in Denmark. Thrips (adults and larvae) were sampled in two strawberry tunnels of the cultivars Murano and Furore from May to August 2018, in the middle and in the edges of the tunnels. The most abundant thrips species found in the tunnels were Frankliniella intonsa and Thrips tabaci adults. Frankliniella intonsa were also the most frequently found species of the immatures sampled, followed by T. tabaci larvae, and other species. The number of thrips differed between the two cultivars, sampling times and location in the tunnel. Frankliniella intonsa was more abundant in the middle of the tunnels, while T. tabaci was more abundant in the edge of the tunnels adjacent to the field margins. The number of thrips peaked by the end of July. Both chemical and biological control should consider species composition and occurrence; hence, a fundamental first step for thrips management is to identify the species present on the target crop.
ABSTRACT
We determined how conidia of arthropod-pathogenic fungi on leaves affected the behavior of two predators-Orius majusculus (Hemiptera: Anthocoridae) and Phytoseiulus persimilis (Acari: Phytoseiidae)-when offered a choice between preying on two-spotted spider mites, Tetranychus urticae (Acari: Tetranychidae), in the presence or absence of infective conidia of Metarhizium brunneum (Ascomycota: Hypocreales) and Neozygites floridana (Entomophthoromycota: Neozygitaceae). The results indicate no significant relation between the presence of conidia and predator behavior. The only indication of interference is between the generalists O. majusculus and M. brunneum, with a trend towards more time spent feeding and more prey encounters turning into feeding events on leaf discs without conidia than on leaf discs with conidia. Our results show that the presence of fungal conidia does not alter the preying behavior of the predators, and using predators and fungi together is not limited by any interference between organisms in the short term.
