A ‘high-end luxury resort’ threatens one of the last remaining refuges for the Grenada Dove Leptotila wellsi, a Critically Endangered species with a global population of just 180 birds. In an unprecedented move the Government of Grenada looks set to sell the whole of the Mount Hartman National Park to make space for a Four Seasons Resort, on the basis of its biodiverse location and “sea-view”. The Mount Hartman National Park – also called ‘The Dove Sanctuary’ - in the south-west of Grenada, supports at least 22% of the global population of the Grenada Dove - equating to just 20 pairs. With such a low population in just a few remnant patches of forest, Grenada Dove is facing an extremely high risk of extinction in the near future. The Sanctuary was created 10 years ago, in order to mitigate for habitat removal elsewhere on the island, partly from development. David Wege, Caribbean Programme Manager at BirdLife International said: “There is more at stake here than just the removal of crucial habitat. The dwindling Grenada Dove population will suffer further from increased isolation, from human disturbance, from non-native animals and with the planting of non-native ‘aesthetic’ vegetation. Such a development in the heart of the Grenada Dove's largest and most well-protected strongholds might lead to the eventual extinction of this species” (BirdLife 19-12-2006).

The identification of the characteristics of bird species that make them susceptible or resilient to climate change has been elusive because non-climatic influences may dominate short and medium-term changes in population and distribution sizes. European scientists studied the 2003 French heat wave, during which other confounding variables remained essentially unchanged. They tested the relationship between population resilience and thermal range by analysing the responses of 71 bird species to a 6-month heat wave (March-August). Species with small thermal ranges showed the sharpest decreases in population growth rate between 2003 and 2004 in locations with the highest temperature anomalies. Thermal range explained the resilience of birds to the heat wave independently of other potential predictors, although it correlated with nest location and broad habitat type used by species. The study included three columbids: Woodpigeon Columba palumbus, Turtle Dove Streptopelia turtur and Stock Dove Columba oenas. All three species were negatively affected by the heat wave during the spring (March-May) with them among the species that were the most severely affected; in fact the Stock Dove displayed the lowest resilience of all birds tested. Pigeons were also negatively affected by the summer heatwave (June-August); however, in contrast to the spring results, during the summer the Stock Dove displayed the third highest resilience of all species.

Jiguet, F. (fjiguet "at" mnhn.fr), Julliard, R., Thomas, C.D., Dehorter, O., Newson, S.E. and Couvet, D. (2006). Thermal range predicts bird population resilience to extreme high temperatures. Ecology Letters 9 (12), 1321-1330.

The Pigeon Paradox: the importance of urban pigeons to global conservation. We are faced with the potential extinction of thousands of species and with radical changes to any of the world’s ecosystems in the next 50–100 years. Paradoxically, conservation may increasingly depend on the ability of people in cities to maintain a connection with nature, a concept a team of scientists have called the “pigeon paradox” because, a great deal of future conservation might rely in part on our interactions with urban ecosystems and their organisms, including non-natives such as pigeons. The paradox lies in the dependence of conservation action worldwide on peoples’ direct experiences with urban nature as an increasing majority of the world’s people and financial resources residue in cities. The future of conservation therefore depends on urban people’s ability to experience nature. In many cities of the world, this means interacting with ecosystems that have been drastically altered by human activity, most likely with organisms and habitats with negative cultural connotations. The most visible aspects of urban landscapes are often non-native species such as pigeons. For the authors, the most satisfying solution to the pigeon paradox is the restoration of as native species and habitats; however, they suggest embracing introduced species in urban circumstances, initially those species with relatively neutral cultural values, such as pigeons to open the door into a broader interest in wild nature and its conservation.

Dunn, R.R. (rob_dunn “at” ncsu.edu), Gavin, M.C., Sanchez, M.C. and Solomon, J.N. (2006). The Pigeon Paradox: dependence of global conservation on urban nature. Conservation Biology 20(6): 1814–1816.

Farmland birds in Sweden have declined by at least as much as in England, despite clear differences between the two countries in the degree of agricultural intensification over the last 30 years. The similarities in bird population trends, despite large differences in patterns of agricultural, may be explained by: (i) common wintering grounds; (ii) similar negative effects of agricultural intensification (England) and intensification/abandonment (Sweden); and (iii) a simultaneous loss of landscape heterogeneity. Population trends in farmland pigeon species differed markedly between the two countries. Between 1976 and 2001 populations of Woodpigeon Columba palumbus, a farmland generalist, declined by 28% in Sweden but increased by 147% in England. Populations of Stock Dove Columba oenas, a farmland specialist, experienced even greater declines, 54% in Sweden in contrast to a 63% increase in England. It was one of only seven species with Swedish populations that have experienced population declines grater than 50%. The increase of Woodpigeon and Stock Dove in England is thought to be a result of the increase in oilseed rape production and a recovery from the organochlorine seed dressings used in the 1950s and the 1960s. None of these hypotheses explains why these species do not show the same trends in Sweden, as they share general food preferences and to some extent also wintering areas. A possible explanation could be the buffer effect; for example, Woodpigeon declines in Sweden may do so because the farmland habitat is a sink habitat reflecting population changes in source habitat types (e.g. forests, bogs and clearings).

Wretenberg, J. (Johan.Wretenberg “at” nvb.slu.se), Lindstrom, A., Svensson, S., Thierfelder, T. and Part, T. (2006). Population trends of farmland birds in Sweden and England: similar trends but different patterns of agricultural intensification. Journal of Applied Ecology 43(6): 1110-1120.

The fourth Inca Dove Columbina inca ever has been recorded in Tennessee, USA. Inca Doves are not migratory and normally associated with dry desert regions in the Southwestern states and Central American countries north of Costa Rica. They are gradually expanding their range northward and eastward across the United States. Dean Edwards of Knoxville, a member of the Tennessee Rare Bird Records Committee of the Tennessee Ornithological Society, reports the four Tennessee Inca dove records as: Shelby County (May 2005); Hamilton County (August 2005); Fayette County (November-December 2005); and the Morristown addition in Hamblen County (October-November, so far, in 2006). The Morristown bird was still present in early November. Tennessee could become part of their breeding range in the not-too-distant future. The appearance of four Inca Doves within 18 months of each other suggests more can be expected. One theory to explain their expansion out of desert areas is that periodic droughts force them to seek better habitat, with more abundant sources of food and water. Whatever the reasons, they are nearly always found near houses and in towns (KnoxNews 12.11.2006).

WWF have just released a report on the impacts of climate change on birds entitled: "Bird Species and Climate Change: The Global Report: A synthesis of current scientific understanding of anthropogenic climate change impacts on global bird species now, and projected future effects". The report includes a comprehensive bibliography on the subject (WWF 14.11.2006).

The Socorro Dove Zenaida graysoni, which has been exinct in the wild since the 1970s, has been successfully bred at London Zoo. Native to Socorro Island 600 miles off the west coast of Mexico the species died out after falling prey to a rising number of feral cats and hunting by humans for food. Overgrazing by sheep also destroyed much of their forest floor habitat. John Ellis, the Zoological Society of London's (ZSL) Curator of Birds, said: "This is an enormous success for London Zoo and a real tribute to the hard work and expertise of our keepers. "I would like to think that this captive breeding success marks a change in the fortunes of the Socorro Dove, and we are delighted to be playing our part in the reintroduction programme." Fewer than 100 birds are thought to exist in captivity and it is hoped that successful captive breeding will increase the birds' numbers sufficiently so that it can eventually be reintroduced into the forests of Socorro (ZSL 30.10.2006; see also BBC News 30.10.2006).

BirdLife’s Global Species Programme continually collates up-to-date information on Globally Threatened Birds. Their Globally Threatened Birds Forum provides an opportunity for both professional and amateur birdwatchers and conservationists to contribute information on Globally Threatened Birds relevant to the assessment of their threat status and their conservation. Contributors can also suggest new species whose status may need reviewing. In April each year, the revisions that have been decided upon from input through the forums will be submitted to the IUCN Red List. New categories become official when the Red List is updated and released later in the year. Contributors who supply information that is used will be explicitly acknowledged.

In the 2006-2007 reviews, discussions are currently open on two pigeon species (both Asian):

• Mindanao Bleeding-heart Gallicolomba crinigera is currently listed as Endangered – should it be downlisted to Vulnerable?

• Tawitawi Brown-dove Phapitreron cinereiceps is currently listed as Critically Endangered; however, recent information is required.
  

Kenneth Meyers (meyer "at" arcinst.org) of the Avian Research and Conservation Institute, Florida was awarded a research grant through the Disney Wildlife Conservation Fund this year for a project entitled "White-crowned Pigeon Patagioenas leucocephala conservation in the Caribbean". This project addresses the highest international priorities for conservation of this Near Threatened species in the Bahamas by training and advising local students and biologists to develop research, management, and education programs.

Ken was previously awarded Disney Wildlife Conservation Fund grants in 2005, 2004, 2003 and 2002 all for research on the White-crowned Pigeon. For details click here.

An educational project to save the Endangered Pink Pigeon Streptopelia mayeri has been launched in Mauritius by the Mauritian Wildlife Foundation (MWF) in a bid to sensitise local people and businesses to the need to protect this rare species. In 1970, there were less than 20 Pink Pigeons on the island; however a recovery programme initiated in 1976 has resulted in the current population totaling ~380 free-living individuals. According to the MWF, even though the number of Pink Pigeon is up, it could go extinct if actions are not taken to sustain past efforts in saving this bird. Until now, the MWF has been able to support the Pink Pigeon conservation entirely from international funding; however, "today foreign funding can only be insured if equivalent local funding is secured" with "this also a way to hand over responsibility to the Mauritian community" MWF indicated. (African News Dimension 26.09.2006).