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Capsule: Transect-based common bird monitoring methods and opportunistic data from citizen scientists are not equal alternatives to mapping of raptors in study plots.Aims: To analyse the ef...

SummaryThe Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.

Farmland biodiversity dramatically declined in Europe during the 20th century. Agri-environment schemes (AES) were introduced in the late 1980s in European Union countries as a solution to combat biodiversity decline. We examined the effectiveness of AES in enhancing biodiversity in a new EU member country (Estonia) over the period of 2010–2012. We compared species numbers and abundance of bumblebees and birds, plus cover of flowers, between three farming systems in two regions of Estonia. Farm types included conventional and two under AES (organic and a less strict environmentally friendly management agreement). Environmentally friendly management practices in Estonia include diversified crop rotations, at least 15% of arable land (including rotational grasslands) under legumes, permanent grassland strips, protection of landscape elements, reduced applications of agrochemicals, etc. The two selected regions (North and South) differed in landscape structure, soil types and crop yields. Flower cover and bird species richness and abundance without the dominant species (skylark) were higher on organic farms. Bumblebee species richness was significantly higher under both types of AES than under conventional farming. Flower cover, abundance and species richness of bumblebees and birds were significantly higher in the more heterogeneous landscapes of Southern Estonia. Environmentally friendly management may be a viable alternative to organic farming for a widely accepted, simple but large-scale greening of agricultural landscapes.

Landscape structure affects farmland bird species richness and diversity at different scales. We develop a predictive, metric-based model for farmland bird species richness in different bird guilds and study how the research area size influences the relationship between bird diversity and landscape metrics. Thirty research locations (randomly selected, each containing four counting points) were located in three counties of Estonia. In early summer 2002 and 2004, two bird counts per point were carried out in each research location. Three landscape metrics (patch density, edge density and Shannon’s diversity index) were calculated at three spatial scales: 100- and 200-m buffer zones around the count points and in a 1 km2 at 1 m × 1 m grain size. Using generalized additive mixed models with repeated measures, we found in most cases that the proportion of variance explained between the bird variables and landscape metrics increased with an increased study area thus demonstrating the effect of scale. Thus, a larger research area is recommended for landscape metrics. At large scales, however, all used landscape metrics were equally good predictors for bird species richness.

Among 66 Estonian farms, representing three subsidy types, birds (especially Sylvia communis and Saxicola rubetra) were more abundant in organic farms that received the largest subsidies and were typically situated in structurally diverse landscapes with a high share of grasslands. Vertical landscape elements most clearly promoted species richness of breeding birds and S. communis. However, among management-related environmental factors considered, only fertilizer input was consistently subsidy-type dependent (highest inputs at medium subsidy levels). High inputs reduced species richness of breeding birds and the density of Alauda arvensis. When environmental factors were accounted for, no significant influences of the subsidy type on birds were observed, but region-specificity remained significant. Our results indicate that differentiation of national subsidies in the AES framework does not necessarily lead to distinct environmental effects, and that targeting of the subsidies on particular species is necessary to effectively improve current environmental conditions.

There was a clear indication that the more intensively farmed areas across the Baltic States of Estonia, Latvia and Lithuania provided habitat for fewer bird species and individuals. The abundance of farmland specialist birds was significantly lower by 20% in the more intensive areas as compared to less intensive ones. The difference could partly be explained by the more heterogeneous landscape and field areas in the latter. An analysis of the data from homogeneous arable fields indicated that agricultural intensification was reflected in a tangible decrease in farmland bird abundance, especially in species in need of edge structures. Considerable improvements are needed in conservation safeguards for the region facing intensification of production.

Readability formulae predict reading outcomes relying on text characteristics but they do not consider reader abilities. This paper describes ways of formulating a reading comprehension formula which includes reader and text characteristics. An experiment embracing 124 subjects and 48 texts serves to demonstrate the mechanisms through which the formula is developed. The applicability of the formula, its degree of precision, and power of predictability are discussed.

This paper introduces a new way of determining the optimal sentence and word lengths for defined groups of readers. The correlation coefficient between the percentage of long sentences and the text comprehension level depends on the positioning of the dividing line between the long sentences and the short sentences. If the line coincides with the line drawn by the readers, the correlation coefficient reaches its maximum. The idea was tested in an experiment on 93 students of Grades 8 and 10 in the secondary school. The optimal values for the 8th‐grade students were sentences of 72 letter spaces and words of 8.5 letters.