Short-term effects of recent land-use changes in Eastern Austria on farmland bird assemblages in a human-dominated landscape

To study effects of short-term land-use changes on birds in a predominantly agriculturally used landscape in Northeastern Austria, birds were surveyed in 22 circular study areas with a diameter of 1 km in 2005 and 2009. Because of the abolition to obligate set-aside land from 2008, it was suspected that the amount of set-aside land would be reduced dramatically. Consequently, a loss of farmland birds was expected. Results show that the amount of set-aside land indeed decreased significantly between 2005 and 2009 from 15.05% to 9.69% (mean proportion of set-aside land per study area). Farmland birds were represented by 20 species in both years. Neither richness and abundance nor species composition of farmland birds were affected by changes of set-aside land. The amount of set-aside land in these landscapes was already high (compared to other areas in Austria) before the amendment of the law and still relatively high after it. Therefore, perhaps changes in the extent of set-aside land were below the threshold to find detectable effects on farmland birds.     

The effect of land type diversity and spatial heterogeneity on farmland birds in Norway

The decline in farmland birds observed throughout Europe during recent decades has attracted much attention. Agricultural intensification or land abandonment are commonly forwarded as key drivers. Several countries have established agri-environmental schemes (AES) to counter these negative trends among farmland birds. This paper reports a study of the relationship between land use and bird species in the agricultural landscape of Norway. The main objective was to investigate the effect of spatial heterogeneity and diversity of land use on total richness and abundance of farmland birds at a national level.Monitoring the distribution and abundance of birds is part of the Norwegian monitoring programme for agricultural landscapes. The monitoring programme is based on mapping of 1 × 1 km squares distributed across the entire agricultural landscape. Within these squares permanent observation points are established for bird monitoring. Detailed interpretation of aerial photographs provides the land classification. We tested the relationship between landscape metrics at different levels of land type detail and species richness and abundance of farmland and non-farmland birds.There was a positive relationship between species richness and abundance of farmland birds and agricultural area. For non-farmland birds the relationship was negative. Spatial heterogeneity of land use was a significant positive factor for both farmland and non-farmland species. High land type diversity was positive for farmland bird richness, but negative for abundance. Non-farmland bird richness was not affected by land type diversity, but abundance had a negative response.The results presented in this paper highlight the importance of a spatial heterogeneous landscape. However, we also found that land type diversity could negatively affect the abundance of both farmland and non-farmland birds. Our findings suggest a need for different management approaches depending on whether the aim is increased species richness or abundance. Achieving both aims with the same means might be difficult. We thus suggest a need for land use analyses before proper management strategies can be implemented.     

Bats are Not Birds – Different Responses to Human Land‐use on a Tropical Mountain

Land‐use intensification has consequences for biodiversity and ecosystem functioning, with various taxonomic groups differing widely in their sensitivity. As land‐use intensification alters habitat structure and resource availability, both factors may contribute to explaining differences in animal species diversity. Within the local animal assemblages the flying vertebrates, bats and birds, provide important and partly complementary ecosystem functions. We tested how bats and birds respond to land‐use intensification and compared abundance, species richness, and community composition across a land‐use gradient including forest, traditional agroforests (home garden), coffee plantations and grasslands on Mount Kilimanjaro, Tanzania. Furthermore, we asked how sensitive different habitat and feeding guilds of bats and birds react to land‐use intensification and the associated alterations in vegetation structure and food resource availability. In contrast to our expectations, land‐use intensification had no negative effect on species richness and abundance of all birds and bats. However, some habitat and feeding guilds, in particular forest specialist and frugivorous birds, were highly sensitive to land‐use intensification. Although the habitat guilds of both, birds and bats, depended on a certain degree of vegetation structure, total bat and bird abundance was mediated primarily by the availability of the respective food resources. Even though the highly structured southern slopes of Mount Kilimanjaro are able to maintain diverse bat and bird assemblages, the sensitivity of avian forest specialists against land‐use intensification and the dependence of the bat and bird habitat guilds on a certain vegetation structure demonstrate that conservation plans should place special emphasis on these guilds.     

Land use types influenced avian assemblage structure in a forest–agriculture landscape in Ghana

The conservation of biodiversity within tropical forest regions does not lie only in the maintenance of natural forest areas, but on conservation strategies directed toward agricultural land types within which they are embedded. This study investigated variations in bird assemblages of different functional groups of forest‐dependent birds in three agricultural land types, relative to distance from the interior of 34 tropical forest patches of varying sizes. Point counts were used to sample birds at each study site visited. Data from counts were used to estimate species richness, species evenness, and Simpson's diversity of birds. Mean species richness, evenness, and diversity were modeled as responses and as a function of agricultural land type, distance from the forest interior and three site‐scale vegetation covariates (density of large trees, fruiting trees, and patch size) using generalized linear mixed‐effect models. Mean observed species richness of birds varied significantly within habitat types. Mean observed species richness was highest in forest interior sites while sites located in farm centers recorded the lowest mean species richness. Species richness of forest specialists was strongly influenced by the type of agricultural land use. Fallow lands, density of large trees, and patch size strongly positively influenced forest specialists. Insectivorous and frugivorous birds were more species‐rich in fallow lands while monoculture plantations favored nectarivorous birds. Our results suggest that poor agricultural practices can lead to population declines of forest‐dependent birds particularly specialist species. Conservation actions should include proper land use management that ensures heterogeneity through retention of native tree species on farms in tropical forest‐agriculture landscapes.     

Nest predation patterns in ground-nesting passerines on the Iberian Peninsula

The idea that ground-nesting birds have a high risk of predation is widely accepted This paper analyzes the nest predation patterns of ground-nesting passerines on the Iberian Peninsula The nest predation rates are higher m open land species x= 71%) than m countryside farmland (10%) or forest birds (29%) The latter species have no differences in daily survival between ground and above-ground nests The higher nest predation in ground-nesting open land species was similar m peninsular Spain and North America We conclude that it is incorrect to generalize that all ground nesters have high nest predation rates, and we discuss the possible link of the high nest predation rates of open land birds to the decline observed in their population trends in Spain     

Are there body size implications for the success of globally introduced land birds?

Verbal models have hypothesized a relation between body size and the successful introduction of animal species. This relation is largely based on studies of intrinsic rate of increase in what have been termed "colonizing" species. From these studies it has been predicted that introduction success should be negatively correlated with body size across taxa but positively correlated within closely related taxa. T examine this relation for globally introduced land birds. Introduced land birds are. on average, larger bodied than extant land bird species. Across species, families, and higher family nodes, global introduction success is significantly related to decreasing body size. However, within taxa there is a significant positive relationship between introduction success and body size. I discuss possible explanations for the observed relations and conclude that an indirect but genuine relationship between the introduction success of land birds and their body size is currently the most plausible.     

THE BIRDS OF THE COCOS-KEELING ISLANDS (INDIAN OCEAN)

The birds of the Cocos-Keeling Islands, in the Indian Ocean, are discussed in the light of specimens and data collected during a stay of eleven months in 1941. Seventeen species were found to be breeding. One of these was an indigenous land bird, four were land birds known to have been introduced, and the remainder were sea birds mostly confined to North Keeling. During this period examples of seventeen species of strays or visitors were taken, of which ten probably occur regularly though in small numbers, while the other seven are true vagrants. Eight of these birds have not so far been recorded from Christmas Island.
Eleven birds listed from the islands by previous visitors were not present in 1941. Two of these were introduced but have failed to maintain themselves, and one, Egrctta garzetta nigripes , seems to be an occasional vagrant. The remaining eight records are all unsatisfactory.     

Effects of landscape composition on farmland and red-listed birds in boreal agricultural-forest mosaics

Farmland birds have declined in large areas of western and northern Europe. This decline has been connected with changes in the agricultural landscape. We studied the effects of landscape composition on birds in a boreal agricultural-forest mosaic in SW Finland. This study was carried out with a grid-based approach: bird pairs were counted in 105 grid squares of 25 ha within an area of 26.25 km². The total density of farmland birds and density of red-listed species were related to the land cover variables using generalized linear modelling (GLM). Farmland birds consist of a variable group of species either breeding or feeding in agricultural land. The model explained a moderate proportion (49%) of the variation in the total density of farmland birds in the landscape. In a regression analysis cover of non-arable agricultural land (semi-natural grasslands, built-up areas) explained a much higher proportion (r²=0.49) of the variation in farmland bird density than that of arable land (cultivated fields and set-aside fields, r²=0.04). Semi-natural grasslands, which have drastically declined throughout NW Europe, and built-up areas (mainly farmyards) had the most significant positive effects on the density of red-listed species. The results emphasize the significance of semi-natural grasslands for the declining red-listed farmland bird species. Birds are usually not restricted to certain patches of habitat but use several patches in their home range. Thus, when studying bird-landscape relations for land use planning, we also recommend grid-based approaches covering the whole landscape variation.     

BIRDS ON GRENADA

Resident and transient birds seen on Grenada in 1971 are listed. Leptotila wellsi still persists. Apus apus is new for the West Indies. Nearly half the resident land birds are regular in both lowlands and highlands.     

Rapid redistribution of agricultural land alters avian richness,abundance, and functional diversity

The conversion of natural, or seminatural, habitats to agricultural land and changes in agricultural land use are significant drivers of biodiversity loss. Within the context of land‐sharing versus land‐sparing debates, large‐scale commercial agriculture is known to be detrimental to biodiversity, but the effects of small‐scale subsistence farming on biodiversity are disputed. This poses a problem for sustainable land‐use management in the Global South, where approximately 30% of farmland is small‐scale. Following a rapid land redistribution program in Zimbabwe, we evaluated changes in avian biodiversity by examining richness, abundance, and functional diversity. Rapid land redistribution has, in the near term, resulted in increased avian abundance in newly farmed areas containing miombo woodland and open habitat. Conversion of seminatural ranched land to small‐scale farms had a negative impact on larger‐bodied birds, but species richness increased, and birds in some feeding guilds maintained or increased abundance. We found evidence that land‐use change caused a shift in the functional traits of the communities present. However, functional analyses may not have adequately reflected the trait filtering effect of land redistribution on large species. Whether newly farmed landscapes in Zimbabwe can deliver multiple benefits in terms of food production and habitat for biodiversity in the longer term is an open question. When managing agricultural land transitions, relying on taxonomic measures of diversity, or abundance‐weighted measures of function diversity, may obscure important information. If the value of smallholder‐farmed land for birds is to be maintained or improved, it will be essential to ensure that a wide array of habitat types is retained alongside efforts to reduce hunting and persecution of large bird species.     

The numbers of land birds, waders, sea birds, land Crustacea, and certain insects on the lagoon islands of Aldabra Atoll

A study was made of the determinants of numbers of species of land birds, waders, breeding sea birds, land Crustacea, and insects on 77 of the lagoon islands of Aldabra Atoll in the Western Indian Ocean. By comparison with other studies, number of plant species and the structural complexity of the vegetation are not significantly related to the number of land bird species; log area accounts for 66.5% of the variance in number. Log area is also the most important factor influencing the number oI wader species. The variables considered account for only 36.2% of the variance in breeding sea bird species; this low figure suggests that other factors are of importance. Isolation of an island is the most important of those considered. Nearly half the variance in the number of insects groups is determined by log number of plant species, while the complexity of the vegetation structure is the only significant variable predicting the number of species of land Crustacea. Differences between the findings of this and other studies are attributed to the particular characteristics or the islands and species considered.
Relatively low z values are found (0.205 for land birds, 0.174 for waders, and 0.136 for land Crustacea), suggesting that inter-island distances do not represent great barriers to the species concerned and immigration and extinction rates are probably in equilibrium.     

Why larger nations have disproportionate threat rates: area increases endemism and human population size

Global Red List data on mammals, birds and plants for over 100non-island nations are used to identify the impact of area, endemism, humanpopulation, and many other social variables (urbanized population,human-dominated land, national wealth, % land protected) on proportions ofthreatened species among nations. Human population size and, especially,proportion of endemic species emerge as the strongest correlates of proportionof threatened species in nations. Area tends to increase both human populationand proportion of endemics and thus increases the proportion of threatenedspecies. Increasing wealth is associated with increased relative threat inmammals and plants. Proportion of land protected is significantly associatedwith decreased relative threat in mammals and birds.     

Recovery from swimming-induced hypothermia in king penguins: effects of nutritional condition

We investigated changes in the rate of oxygen consumption (V O2) and body temperature of wild king penguins (Aptenodytes patagonicus) in different nutritional conditions during recovery after exposure to cold water. Over time, birds undertook an identical experiment three times, each characterized by different nutritional conditions: (1) having recently completed a foraging trip, (2) after fasting for many days, and (3) having been refed one meal after the fast. The experiments consisted of a 2-h session in a water channel followed by a period of recovery in a respirometer chamber on land. Refed birds recovered significantly more quickly than fed birds, in terms of both time to reach resting V O2 on land and time to reach recovery of lower abdominal temperature. Previous work found that when penguins are in cold water, abdominal temperatures decrease less in refed birds than in fed or fasted birds, suggesting that refed birds may be vasoconstricting the periphery while perfusing the gut region to access nutrients. This, alongside an increased resting [V O2], seems the most reasonable explanation for why refed birds recovered more quickly subsequent to cold-water exposure in this study; that is, vasoconstriction of the insulative periphery meant that they lost less heat generated by the body core.     

Avian Influenza A (H7N9) Virus in a Wild Land Bird in Central China,Late 2015

正Dear Editor,In early 2013,the first case of a human infection with avian influenza A(H7N9)virus was reported in the Yangtze River Delta region of China(Liu et al.2013).Since early2013,a total of 1533 laboratory-confirmed human infections with avian H7N9 viruses have been reported to the     

Downsized Dinosaurs: The Evolutionary Transition to Modern Birds

Living birds are the most diverse land vertebrates and the heirs of a rich chapter in the evolution of life. The origin of modern birds from animals similar to Tyrannosaurus rex is among the most remarkable examples of an evolutionary transition. A wealth of recently discovered fossils has finally settled the century-old controversy about the origin of birds and it has made the evolutionary saga toward modern birds one of the best documented transitions in the history of life. This paper reviews the evidence in support of the origin of birds from meat-eating dinosaurs, and it highlights the array of fossils that connect these fearsome animals with those that fly all around us.     

Factors controlling the spatial species richness pattern of four groups of terrestrial vertebrates in an area between two different biogeographic regions in northern Spain

Aim To examine the influence of environmental variables on species richness patterns of amphibians, reptiles, mammals and birds and to assess the general usefulness of regional atlases of fauna. Location Navarra (10,421 km²) is located in the north of the Iberian Peninsula, in a territory shared by Mediterranean and Eurosiberian biogeographic regions. Important ecological patterns, climate, topography and land‐cover vary significantly from north to south. Methods Maps of vertebrate distribution and climatological and environmental data bases were used in a geographic information systems framework. Generalized additive models and partial regression analysis were used as statistical tools to differentiate (A) the purely spatial fraction, (B) the spatially structured environmental fraction and (C) the purely environmental fraction. In this way, we can evaluate the explanatory capacity of each variable, avoiding false correlations and assessing true causality. Final models were obtained through a stepwise procedure. Results Energy‐related features of climate, aridity and land‐cover variables show significant correlation with the species richness of reptiles, mammals and birds. Mammals and birds exhibit a spatial pattern correlated with variables such as aridity index and vegetation land‐cover. However, the high values of the spatially structured environmental fraction B and the low values of the purely environmental fraction A suggest that these predictor variables have a limited causal relationship with species richness for these vertebrate groups. An increment in land‐cover diversity is correlated with an increment of specific richness in reptiles, mammals and birds. No variables were found to be statistically correlated with amphibian species richness. Main conclusions Although aridity and land‐cover are the best predictor variables, their causal relationship with species richness must be considered with caution. Historical factors exhibiting a similar spatial pattern may be considered equally important in explaining the patterns of species richness. Also, land‐cover diversity appears as an important factor for maintaining biological diversity. Partial regression analysis has proved a useful technique in dealing with spatial autocorrelation. These results highlight the usefulness of coarsely sampled data and cartography at regional scales to predict and explain species richness patterns for mammals and birds. The accuracy of models appears to be related to the range perception of each group and the scale of the information.     

Rapid warming is associated with population decline among terrestrial birds and mammals globally

Animal populations have undergone substantial declines in recent decades. These declines have occurred alongside rapid, human‐driven environmental change, including climate warming. An association between population declines and environmental change is well established, yet there has been relatively little analysis of the importance of the rates of climate warming and its interaction with conversion to anthropogenic land use in causing population declines. Here we present a global assessment of the impact of rapid climate warming and anthropogenic land use conversion on 987 populations of 481 species of terrestrial birds and mammals since 1950. We collated spatially referenced population trends of at least 5 years’ duration from the Living Planet database and used mixed effects models to assess the association of these trends with observed rates of climate warming, rates of conversion to anthropogenic land use, body mass, and protected area coverage. We found that declines in population abundance for both birds and mammals are greater in areas where mean temperature has increased more rapidly, and that this effect is more pronounced for birds. However, we do not find a strong effect of conversion to anthropogenic land use, body mass, or protected area coverage. Our results identify a link between rapid warming and population declines, thus supporting the notion that rapid climate warming is a global threat to biodiversity.     

Environmental Gradients Explain Species Richness and Community Composition of Coastal Breeding Birds in the Baltic Sea

Scientifically-based systematic conservation planning for reserve design requires knowledge of species richness patterns and how these are related to environmental gradients. In this study, we explore a large inventory of coastal breeding birds, in total 48 species, sampled in 4646 1 km² squares which covered a large archipelago in the Baltic Sea on the east coast of Sweden. We analysed how species richness (α diversity) and community composition (β diversity) of two groups of coastal breeding birds (specialists, i.e. obligate coastal breeders; generalists, i.e. facultative coastal breeders) were affected by distance to open sea, land area, shoreline length and archipelago width. The total number of species per square increased with increasing shoreline length, but increasing land area counteracted this effect in specialists. The number of specialist bird species per square increased with decreasing distance to open sea, while the opposite was true for the generalists. Differences in community composition between squares were associated with differences in land area and distance to open sea, both when considering all species pooled and each group separately. Fourteen species were nationally red-listed, and showed similar relationships to the environmental gradients as did all species, specialists and generalists. We suggest that availability of suitable breeding habitats, and probably also proximity to feeding areas, explain much of the observed spatial distributions of coastal birds in this study. Our findings have important implications for systematic conservation planning of coastal breeding birds. In particular, we provide information on where coastal breeding birds occur and which environments they seem to prefer. Small land areas with long shorelines are highly valuable both in general and for red-listed species. Thus, such areas should be prioritized for protection against human disturbance and used by management in reserve selection.     

Is the range size of migratory birds constrained by their migratory program?

Aim Intuitively, species in which the individuals migrate long distances between summer and winter quarters should be more likely to disperse and colonize new breeding areas than resident species. However, it has repeatedly been noted that many bird species with large ranges are residents. This paradox was tested on land birds breeding in the boreal forest of the Palaearctic, the largest uninterrupted stretch of habitat on earth. Methods The longitudinal distribution of two land bird communities on each side of the Eurasian continent, in Scandinavia and eastern Siberia, were used to test whether migratory birds indeed have a lower colonization success than resident birds. Results The migratory species are significantly less likely than resident species to have a range including both regions. The pattern held true even after controlling for latitudinal effects and local abundance, and was also observed at the level of genus and family. Main conclusions The relatively low colonization success of migratory species into new breeding areas may be because these new areas require novel migratory programs (migratory distance, direction and timing) in order for the birds to reach suitable wintering grounds.     

Can intensively farmed arable land be favourable for birds during migration? The case of the Eurasian golden plover Pluvialis apricaria

Today's intensive farming practices are known to have affected farmland biodiversity negatively in many different ways. As far as birds are concerned, they are known to have suffered during both summer and winter. Relatively little is known about the effects on birds during migration. We studied the stopover ecology of the Eurasian golden plover Pluvialis apricaria, a species listed in EU Birds Directive, in intensively farmed arable land in southernmost Sweden in the autumns of 2003–2007. We used key ecological variables (length of stay, fat deposition and moult) as fitness proxies to evaluate how the birds manage in this habitat. Eurasian golden plovers were present in large numbers mainly on arable fields from early August to November and radio‐tagged birds were found to stay in the area for up to three months. Adult birds carried out a substantial part of their flight feather moult during their stay. Body mass increased only somewhat during moult, but from the last stages of moult and onwards fuel loads corresponding to 24% above lean body mass (LBM) were accumulated at a rate of 0.5% of LBM per day, before the birds departed. Juveniles arrived later, from mid Sep., and had a similar pattern of fuel deposition. The fact that the birds choose to stay for long periods, moult in the area, and manage to store substantial fuel loads strongly suggests that Eurasian golden plovers do well in this intensively farmed arable land.