scholarly journals Does organic farming benefit farmland birds in winter?

2009 ◽  
Vol 6 (1) ◽  
pp. 82-84 ◽  
Author(s):  
D. E. Chamberlain ◽  
A. Joys ◽  
P. J. Johnson ◽  
L. Norton ◽  
R. E. Feber ◽  
...  

The generally higher biodiversity on organic farms may be influenced by management features such as no synthetic pesticide and fertilizer inputs and/or by differences in uncropped habitat at the site and landscape scale. We analysed bird and habitat data collected on 48 paired organic and conventional farms over two winters to determine the extent to which broad-scale habitat differences between systems could explain overall differences in farmland bird abundance. Density was significantly higher on organic farms for six out of 16 species, and none on conventional. Total abundance of all species combined was higher on organic farms in both years. Analyses using an information-theoretic approach suggested that both habitat extent and farm type were important predictors only for starling and greenfinch. Organic farming as currently practised may not provide significant benefits to those bird species that are limited by winter food resources, in particular, several declining granivores.

2011 ◽  
Vol 33 (1) ◽  
pp. 49 ◽  
Author(s):  
Alex S. Kutt ◽  
Alaric Fisher

The invasion of exotic pasture species into intact woodlands has the potential to affect native fauna by altering habitat structure and ecosystem function. The spread of these weeds is generally in concert with cattle grazing, so that fauna or habitat change is due to multiple interrelated causes. In this study we investigated whether the spread of the introduced pasture grass Bothriochloa pertusa and replacement of the native bluegrass B. ewartiana in eucalypt woodlands of northern Queensland has had an effect on terrestrial vertebrate fauna. We located 40 sites that sampled a range of native and introduced pastures cover, and investigated the spatial pattern of abundance with canonical analysis of principle coordinates, and correlation of the habitat attributes on the ordination space. We then selected a subset of four habitat attributes (eliminating highly colinear variables) and modelled species response to each using an information-theoretic approach. Thirty-one species (26 birds, one mammal and four reptiles) and two summary variables (bird abundance and richness) had best subset Akaike Information Criteria models with reliable parameters estimates. Seventeen models contained the B. pertusa frequency term and a further 16 had a term relating to upper storey cover (tree cover >10, 5–10 or 3–5 m). Though pasture grass cover, grazing and habitat features were correlated and thus we cannot ascribe B. pertusa as the sole determinant of fauna species change, this study has demonstrated that tropical savanna woodlands with changing Bothriochloa dominance from native to introduced species have different fauna species composition. In particular bird species richness, ground nesting species (e.g. rufous songlark Cincloramphus mathewsi, golden-headed cisticola Cisticola exilis) and terrestrial reptiles (e.g. Carlia munda and Ctenotus taeniolatus) declined. Disturbance-tolerant species such as Australian magpie Cracticus tibicen and yellow-throated miners Manorina flavigula increased in abundance in exotic pasture-dominated sites. As pastoral intensification continues in northern Australian rangelands there is a potential for significant change in the relative abundance and composition of vertebrate fauna and the reduction or loss of some species in the landscape.


Author(s):  
Irina Herzon

Intensification of agricultural land-use was shown to be the key reason behind declines in wildlifespecies associated with farmland. I looked at scenarios of agricultural development across the Baltic states ofEstonia, Latvia and Lithuania, and the ways they are seen to affect farmed environments as a habitat offarmland bird species. Community richness and abundance of many farmland bird species were positivelyrelated to the number of non-cropped elements within farmland, the local mixture of annual crop and grassfields, and the variety of field types. The above positive associations were strongest in open landscapes.There was a clear indication that the more intensively farmed areas across the region provided habitat forfewer bird species and individuals. The difference could partly be explained by the more heterogeneouslandscape and field areas in the latter. Within homogenous arable fields intensification of field managementwas reflected in a tangible decrease in farmland bird abundance, especially in species in need of edgestructures.Based on the interviews in Estonia and Finland I explored farmers’ interest in and knowledge offarmland wildlife, their understanding of the concept of biodiversity, and awareness of the potential causesbehind declines of farmland birds. Many farmers viewed biodiversity from a narrow perspective oftenexcluding species directly related to farming. In Finland farmers expressed concern about the decline incommon farmland species, but Estonian farmers did not, which might be related to the fact that these speciesare still very common. In both countries farmers rated intensification of agriculture as the major drivingforce behind farmland bird declines. The expressed interest in wildlife positively correlated with willingnessto undertake wildlife-friendly measures. Only farmers with agri-environment contracts targeted specificallyat biodiversity enhancement were more knowledgeable about practical on-farm activities favouring wildlife,and were more willing to employ them that the rest.The results suggest that, by contributing to simplification of the farmland structure, homogenisationof crops, and increase in intensity of field use EU agricultural policies will have a detrimental effect onfarmland bird populations in Eastern Europe. Farmers are on the whole positive to the idea of supportingwildlife in the fields, and are concerned about its decline, but they require payments to offset their incomeloss and extra work. Biodiversity conservation should be better integrated into the agri-environmentprogrammes if it to serve as awareness tool for farmers. I argue that with a foreseen tripling of cereal yieldsacross the region, the EU Council’s Göteborg target of slowing biodiversity decline by 2010 may not berealistic unless considerable improvements are made into the EU agricultural policy for the region.


2021 ◽  
Author(s):  
Gianpasquale Chiatante ◽  
Michele Panuccio

AbstractThe species–habitat relationships can change during the year because of the seasonality of resources. Therefore, the investigation of habitat use by animals in each season plays a fundamental role in their conservation. The main aim of this research was to investigate the raptor community that spends the winter in Armenia, southern Caucasus, and to explore its relationship with environmental features, such as land use and topography. During January 2012, we collected data by carrying out 15 roadside counts along which we calculated three community parameters: the relative abundance, the species richness, and the species diversity. Then, we carried out a multiple linear regression with the Information-Theoretic Approach, to explain the relationship between the parameters and environmental variables. Besides, we computed a Canonical Correspondence Analysis (CCA) between the species and the environment around their observations. As a general pattern, the community was associated with permanent crops, maybe because of their heterogeneity, which in turn allows them to support higher densities of prey during the winter. The most abundant species was the Black Kite (Milvus migrans), followed by the Common Kestrel (Falco tinnunculus) and the Griffon Vulture (Gyps fulvus). To our knowledge, this is one of the first studies investigating the wintering raptor community in the Caucasus, with raptors generally studied in this area during the breeding season and migration.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 390
Author(s):  
Pouya Manshour ◽  
Georgios Balasis ◽  
Giuseppe Consolini ◽  
Constantinos Papadimitriou ◽  
Milan Paluš

An information-theoretic approach for detecting causality and information transfer is used to identify interactions of solar activity and interplanetary medium conditions with the Earth’s magnetosphere–ionosphere systems. A causal information transfer from the solar wind parameters to geomagnetic indices is detected. The vertical component of the interplanetary magnetic field (Bz) influences the auroral electrojet (AE) index with an information transfer delay of 10 min and the geomagnetic disturbances at mid-latitudes measured by the symmetric field in the H component (SYM-H) index with a delay of about 30 min. Using a properly conditioned causality measure, no causal link between AE and SYM-H, or between magnetospheric substorms and magnetic storms can be detected. The observed causal relations can be described as linear time-delayed information transfer.


Author(s):  
R. V. Prasad ◽  
R. Muralishankar ◽  
S. Vijay ◽  
H. N. Shankar ◽  
Przemyslaw Pawelczak ◽  
...  

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