Akkervogels

BBS population trends are published annually for 61 bird species in Scotland, and the latest results show that 2012 was a particularly bad year for a number of migrant birds, including Whitethroat (Sylvia communis) and Swift (Apus apus). The latest figures from the Breeding Bird Survey (BBS) show that numbers of Swifts fell by 42% in Scotland between 2011 and 2012. For Swifts, the latest drop in numbers is the third annual decline in a row, and follows a 57% decline in Scotland since the mid-1990s. Linnets (Carduelis cannabina), which live on farmland, also did badly in 2012, with the population declining by nearly 50% between 2011 and 2012, taking the numbers of this small finch to their lowest level in Scotland since the survey began in 1994.

Trichomonas gallinae is an emerging pathogen in wild birds, linked to recent declines in finch (Fringillidae) populations across Europe. Globally, the main hosts for this parasite are species of Columbidae (doves and pigeons); here we carry out the first investigation into the presence and incidence of Trichomonas in four species of Columbidae in the UK, through live sampling of wild-caught birds and subsequent PCR. We report the first known UK cases of Trichomonas infection in 86% of European Turtle Doves Streptopelia turtur sampled, along with 86% of Eurasian Collared Doves Streptopelia decaocto, 47% of Woodpigeons Columba palumbus and 40% of Stock Doves Columba oenas. Birds were more likely to be infected if the farm provided supplementary food for gamebirds. We found three strains of T. gallinae and one strain clustering within the Trichomonas tenax clade, not previously associated with avian hosts in the UK. One T. gallinae strain was identical at the ITS/5.8S/ITS2 ribosomal region to that responsible for the finch trichomonosis epizootic. We highlight the importance of increasing our knowledge of the diversity and ecological implications of Trichomonas parasites in order further to understand the sub-clinical impacts of parasite infection.

"Es ist zum Weinen", sagt Hubert Ull, der Vorsitzende der Jägerschaft Lingen. "Als Landwirt fahre ich jeden Tag durch die Felder, aber in diesem Jahr habe ich hier noch nicht einen jungen Fasanen (Phasianus colchicus) gesehen." Niedersachsen, insbesondere das Emsland, gilt neben dem nördlichen Nordrhein-Westfalen als Hauptverbreitungsgebiet des bunt gefiederten Geflügels. In den vergangenen Jahren ist dessen Zahl dramatisch zurückgegangen. Wurden in Niedersachsen vor fünf Jahren noch 150000 Fasane erlegt, waren es zuletzt knapp 60000 – laut Landesjagdbericht die niedrigste Quote seit 1959.

In recent years Indian ornithologists have observed a sharp decline in house sparrow (Passer domesticus) populations across West Bengal, Bangalore, Punjab, Rajasthan, Delhi and Haryana due to danger posed to their survival by a host of factors, such as lack of nesting sites due to modern architecture of building, and lack of seed and insect food. The aim of this paper was to investigate the possible causes for the decline of house sparrow in Sivakasi Taluk during December 2011 to December 2012. In Naranapuram (190 ± 4.89) and Duraichamipuram (83.33 ± 0.94) a high number of house sparrows were recorded. Moderate numbers of sparrows were found in Kalayarkuruchi (40 ± 1.63), Anaiyur (34 ± 1.63) and Pudhukottai (27.66 ± 1.24). The sparrows were completely absent in Achankulam and Alankulam. The house sparrow population was found to be higher in the rural areas when compared to the urban areas in the selected study sites.

A recent estimate has pegged the population of the small, dark and swift-moving birds at 260,000. That's down from 400,000 birds counted in 2008, according to an Audubon California survey. The tricolored blackbird (Agelaius tricolor) – with its red shoulder patch and a white bar of feathers on its wing – differs from the more common red-winged blackbird in that it is a species that lives in tight colonies. "We are, absolutely, concerned about the species because we've had a 33 percent decline in their numbers between 2008 and 2011," said Keiller Kyle, conservation project director for Audubon California. The declines are being seen throughout the San Joaquin and Sacramento valleys and as far south as Riverside County. The low population numbers are a stark contrast to what was seen in 1937, when it was estimated that as many as 3 million tricolored blackbirds darkened the sky statewide. With substantially lower populations today, the fear is that if the species is not safeguarded, it could become endangered and swiftly go the way of two colonial bird species – the passenger pigeon and the Carolina parakeet. Both are now extinct.

Der Steinkauz (Athene noctua) hat bei uns seit Jahrhunderten in unmittelbarer Nachbarschaft des Menschen gelebt, oft als Untermieter in Scheunen und Ruinen. In der bäuerlichen Bevölkerung galt er mit seinen mysteriösen nächtlichen Rufen als «Totenvogel», bei den alten Griechen war er das Sinnbild der Göttin Athene, was im wissenschaftlichen Namen zum Ausdruck kommt. Durch den Rückgang extensiv bewirtschafteter Obstgärten setzte ab den Fünfzigerjahren ein schneller Rückgang ein, und heute sind die kleinen Kobolde grösstenteils verschwunden.

A well-known Yukon bird biologist says kestrels, the smallest member of the falcon family in North America, are rapidly disappearing from the territory. Dave Mossop says the American kestrel (Falco sparverius) population in Yukon has dropped by about 90 per cent over the past decade. He says the decline is about 65 percent in North America overall. “This is a little bird that sits at the top of the food web in which it lives,” he said. “And so, depending as it does on the whole system below it, it becomes a wonderful indicator species of things that are changing.”

Many groups of organisms found in agricultural areas are experiencing catastrophic declines, including: birds (e.g., Nebel, S. et al. 2010. Declines of aerial insectivores in North America follow a geographic gradient. Avian Conserv. Ecol. 5(2): 1. [online]); bats (e.g., Wickramasinghe, L.P. et al. 2004. Abundance and species richness of nocturnal insects on organic and conventional farms: effects of agricultural intensification on bat foraging. Conserv. Biol. 18: 1283–1292); amphibians (e.g., Blaustein, A.R. 2011. The complexity of amphibian population declines: understanding the role of cofactors in driving amphibian losses. Ann. N. Y. Acad. Sci. 1223: 108-119); bumblebees (e.g., Cameron, S.A. et al. 2011. Patterns of widespread decline in North American bumble bees. Proc. Nat. Acad. Sci. 108(2): 662-667); butterflies (e.g., Van Dyck, H. et al. 2009. Declines in common, widespread butterflies in a landscape under intense human use. Conserv. Biol. 23(4): 957-965); moths (e.g., Conrad, K.F. et al. 2006. Rapid declines of common, widespread British moths provide evidence of an insect biodiversity crisis. Biol. Conserv. 132(3): 271-291); and carabid beetles (Brooks, D. R. et al. 2012. Large carabid beetle declines in a United Kingdom monitoring network increases evidence for a widespread loss in insect biodiversity. J. Appl. Ecol. 49(5): 1009-1019). There is an urgent need for greater understanding of the degree to which exposure to neonicotinoid insecticides may be contributing to these declines, and how exposure to these chemicals may be interacting with other negative pressures on biodiversity in agricultural areas.