2010 BOC Meetings

2 November 2010: The Atlas of the Breeding Birds of Arabia (ABBA) project — Mr Michael Jennings

Mr Jennings gave a presentation on the Atlas of the Breeding Birds of Arabia (ABBA) project, an overview on the issues which fashion bird distribution in Arabia and species conservation.  The atlas started in 1984 with the objective of defining the breeding distribution and ecological requirements of birds in Arabia, that is the Arabian Peninsula and the Socotra Archipelago (Yemen).  The project reviewed published sources and some museum specimens but the main source of distributional data was from nearly 500 field observers.  His own ABBA Surveys (40 surveys between 1985 and 2009) where to the corners of Arabia poorly recorded by others.  Bird distribution in Arabia is a result of a number of important factors.  The arid climate restricts breeding species over large areas to a few Saharo-Indian arid land specialists, often with a nomadic tendency.  The topography and habitats of Arabia include a wide range of geology; granite, sandstone, lava flows, limestone, not to mention sand dunes.  Mountains rise to 3700 m in the south west with juniper forests and there are extensive mangrove swamps on the coast.  The varied zoogeographical influences play a significant role. There are many Afrotropical species in the south-west (both residents and breeding summer visitors) and an Indian flavour to the eastern part of the peninsula.  However the predominant influence throughout is the Palaearctic.  Arabia is also a centre of endemism with 11 endemic landbirds, mostly in the south-west highlands, three endemics of the seas around Arabia and nine endemics in the Socotra Archipelago.  A stealthy change to the Arabian avifauna in recent years has been the establishment of at least 20 ferally breeding exotic birds.  Major changes to the Arabian environment since about the 1970s have added many species to the avifauna, for example through the development of huge areas of irrigated agriculture and dairy farms and artificial wetlands.  For example in the well studied area within 100 km of Riyadh, diversity has increased from 44 breeding species identified in 1977 to 88 breeding species by 2002.  On the other hand the birds of Arabia also have to contend with a wide variety of conservation pressures, overgrazing, charcoal burning, pollution, hunting, the introduction of exotic predators as well as habitat change on a grand scale.  Several species are now under threat.   When the atlas was published in July 2010 it included 273 confirmed breeding species and another 24 which probably breed.

21 September 2010: Eggs dressed and undressed — Dr Andrew Gosler

This talk brought up to date the speaker’s work on eggshell pigmentation carried out since his talk to the BOC given on 7 December 2004. An important study conducted after that presentation, on the relationship between eggshell pigmentation, shell thickness and DDT contamination in the Eurasian Sparrowhawk Accipiter nisus had developed directly from the discussion engaged in after the earlier talk at the BOC. Dr Gosler was therefore delighted to be speaking again to the Club and looked forward to yet more insightful comments.

The current talk started with a recap of the principal points presented previously. Studies of Great Tit Parus major eggs in Wytham Woods had shown that such pigmentation was intimately related to eggshell structure, calcium availability, and water loss in incubation. The more recent work had shown that the pigment spots on the eggshell of Great Tit eggs marked areas of thinner shell, and that the shell thickness, especially around the widest part of the shell (here referred to as the shoulder) was related to a measure of pigment pattern known as ‘spread’. This pigment spread measure appeared to have no heritable element, i.e. variation in it was influenced entirely by environmental factors. An important environmental factor was local calcium availability, which affected the birds through its effect on the density of small snails, which were the chief source of calcium for females during egg formation. So in areas where calcium was in short supply, there were fewer snails, and the tits laid thinner-shelled eggs, which showed a greater spread of pigment. Over the last 20 years, this pigment spread measure had declined in a striking way, which reflected a significant decline observed in soil calcium in Wytham. The most likely cause of this was thought to be acid precipitation, which had the potential to leach calcium even from soils overlying limestone.

The Sparrowhawk study had developed from Prof. Cheke’s earlier suggestion that, if protoporphyrin pigment were incorporated within the eggshell to compensate (strengthen) for shell-thinning, since DDT was known to cause eggshell thinning in the Sparrowhawk, maybe it also affected the eggshells’ pigmentation in that species. The subsequent study, here reported, showed a complex relationship between pigmentation, shell thickness and DDE content of eggs, but that essentially it was correct that in this species also, protoporphyrin was incorporated where the shell was thinner, and that indeed this occurred more in eggs that contained higher concentrations of DDE. The fact that the apparent adaptation of adding this pigment where the shell was thinner had been found in such distantly related species as the Great Tit and Sparrowhawk (the latter being a species whose diet should prevent it normally from being calcium stressed) suggested that this might be a very primitive adaptation in birds.

Dr Gosler also presented some micrographs of Great Tit eggshell sections showing the layered distribution of pigments through the shell. In discussion after the talk, the suggestion that this might strengthen the shell by forming a laminate structure caused much interest.

22 June 2010: Birdlife International’s Important Bird Area programme: a global perspective — Dr Lincoln Fishpool

Important Bird Areas (IBAs) are the sites-based component of BirdLife’s conservation work.  The origins of IBAs date back to the late 1970s, when ICBP, the forerunner of BirdLife, was asked to help develop the means of implementing the European Union’s Bird Directive.  Since then, the programme has become global and over 10,000 IBAs have now been identified worldwide.

IBAs are identified using a set of standardised selection categories using data gathered locally, analysed nationally and coordinated regionally, and it is these local-to-global connections that are one of the reasons for the success of the programme. One measure of this success has been the designation of new protected areas – for example, as the result of a ten-country project in Africa, the proportion of IBAs with legal protection increased from 55% to 70% between 1998 and 2007.

Information for more than 200 countries and territories has been published in seven regional directories and over 120 national publications, while boundaries have been digitised for about 95% of sites. With the majority of sites now identified, at least on land, emphasis is shifting to monitoring.  Using a simple methodology, information is collected locally, largely by volunteers, to produce indicators of ‘state’, ‘pressure’ and ‘response’ for each site.  These can be integrated to provide assessments of status and trends at IBAs nationally and regionally, which have powerful advocacy messages.

While IBA coverage now extends to almost all terrestrial and freshwater parts of the globe, this is not the case for the marine environment.  Methods for IBA identification at sea are still being developed, including, for example, exploring how the results of seabird satellite tracking can be used to inform IBA boundary designation.

BirdLife has been collaborating with Wetlands International, and other organisations, in the development of a ‘Critical Site Network Tool’ for waterbirds within the region covered by the Africa-Eurasian Waterbird Agreement.  Combining IBA information with International Waterbird Census data, the ‘Wings Over Wetlands’ project has looked at site networks from a flyways perspective.  This has included, for example, assessments of how complete the coverage of each population is, based upon comparisons of total numbers held at known sites with the size of the population as a whole, so pointing up potential gaps. The tool can be seen atwww.wingsoverwetlands.org/csntool.

IBA networks are also being examined for their likely resilience in the face of projected climate change between now and 2080.  This includes assessments of the scale of projected turn-over of priority species at sites.  These studies have also highlighted those sites whose climates are not anticipated to change significantly over this period, something which has further heightened their importance for conservation.

27 April 2010: Short talks by members of the club

After dinner a series of short talks was given. Prof. Robert A. Cheke spoke onAn indigenous trap for mass capture of Red-billed Quelea. He described a basket trap that he was shown by Richard N. Magoma, James Mabuga and Boaz Mtobesya of the Tanzanian Ministry of Agriculture, Food Security and Co-operatives, which is used by bird trappers in the Kondoa area of Tanzania to catch Red-billed Quelea Quelea quelea aethiopica in the dry season. The traps are woven from African Star Grass Cynodon nlemfluensiinto torus-shaped structures, resembling a wheel, c.60 cm in diameter, 20 cm deep and 2 m in circumference, with central holes that serve as entrances for birds. The hole on one side (15 cm) is larger than on the other (10 cm), with the latter tapered inwards. Two methods are used: one in water and one on land, with a decoy bird inside from the outset in both. When trapping at drinking sites, the basket is partially submerged with the large hole uppermost, and grasses then conceal much of the basket. Birds lured into the entrance to drink become trapped. Similarly, when used on land, the basket is baited with a panicle of bulrush millet or millet seeds, and placed in a feeding zone with the smaller hole uppermost and the larger hole underneath blocked. A trapper deploys 5–10 traps from which 500–1,000 birds can be caught per day. Any surplus to the trappers’ requirements are sold, providing much-needed income for the trappers and protein for the buyers. Different ways in which the birds are cooked were described and the results of experiments by B. Mtobesya using similar traps made of wire mesh discussed as a means of localised pest control, with care taken to release any non-target birds caught.

Dr Robert Prys-Jones’ talk was entitled The case of the Large-billed Reed Warbler: museum collections shed light on an unknown species. Following its description in 1867, from a specimen taken in north-west India, Large-billed Reed Warbler Acrocephalus orinus led a twilight existence for 135 years, with no further specimens discovered and an increasing tendency to consider it either an unusual specimen of a known species or a hybrid. However, in 2002 a re-analysis that included a molecular study demonstrated that it was a distinct species, and in 2006 a live bird was discovered in Thailand. Subsequent intensive museum study turned up sufficient overlooked specimens to provide an overview of its annual cycle, suggesting that it bred in south-central Asia, migrated across India and wintered in south-east Asia. Breeding in north-east Afghanistan and Tajikistan has now been confirmed. More detail, including references, can be found at http://www.nhm.ac.uk/nature-online/species-of-the-day/collections/our-collections/acrocephalus-orinus/index.html.

David Fisher showed photographs of hummingbirds taken on three-week trips to Ecuador in 2009 and Mexico in 2010. In Ecuador he had seen 58 species and photographed 34 of them reasonably well, in Mexico he had seen 26 species but only managed to photograph three. He explained that this was due to the different views in the two countries concerning hummingbird feeders. In Ecuador they are commonplace at every lodge, whereas in Mexico they simply don’t exist. David had been informed that there are no feeders in Mexico because several years ago an influential biologist suggested that they might be harmful to hummingbirds, and this view spread rapidly with the result that feeders are not used at all—which is quite remarkable given how common they are in the USA, Costa Rica, Ecuador and other countries. David explained that at Umbrellabird Lodge, run by the Jocotoco Foundation, feeding has reached a new level, with large salad trays being used rather than commercial flower-like feeders. These attract dozens of hummingbirds at a time, and 200–300 individuals of ten species were simultaneously present on the lodge veranda or waiting in the surrounding bushes. He showed photographs of each of the species present.

Martin Gauntlett addressed the question How many species of extant birds are there? The first edition of Howard & Moore appeared in 1980 and listed 8,984 species. At the time, Pink-footed Goose Anser brachyrhynchus was still considered a subspecies of Bean Goose A. fabalis. Ten years later, when Sibley & Monroe put the DNA cat among the taxonomic pigeons, the number had grown to 9,598. BirdLife International takes its own line on species-level splits and its June 2009 posting listed 9,803, plus 126 under review. Many of the latter will probably be accepted. Clements follows the AOU. Its 6.4 version in December 2009 listed 9,888 species. The third edition of Howard & Moore appeared in 2003 and took a rather conservative approach, requiring peer-reviewed literature to accept a change, and listed 9,593 species. Now there isHBW, which is likely to total 9,692 species. Its earlier volumes were more conservative and a taxonomic round-up at the end of the series is anticipated. Comparing their lists, the four 21st century sources agree on just 9,359 species (assuming HBW agrees for all species treated in forthcoming volumes) but between them they cover 10,172 species, a difference of 813. Finally, there is the IOC English names committee. In December 2009 it listed 10,366 species. In March 2010 this had increased 10,384, an additional 18 species in three months. Thus, the answer to the question is that (in April 2010) there were between 9,351 and nearly 10,500 extant species, and the list was growing by six species per month.

In pursuit of a dream to observe Steller’s Sea Eagles Haliaeetus pelagicus on the sea-ice off Hokkaido, Richard Price, and his wife Helen, travelled to Japan in February 2009. In addition to realising his dream, with the Steller’s jousting with White-tailed Eagles Haliaeetus albicilla, they also saw Japanese (Red-crowned) Cranes Grus japonensis dancing in the snow. A bonus was a detour on the way to Hokkaido via Kyushu, the southernmost large island in Japan. Here they saw up to 10,000 Hooded Cranes G. monacha and White-naped Cranes G. vipio, together with small numbers of Sandhill Cranes G canadensis and European Cranes G. grus and two Siberian White Cranes G. leucogeranus.

16 March 2010: Birds of the Comoros Islands — Dr Julian Hume

After dinner, Dr Hume gave an informative and well-illustrated talk on the The Comoros comprise four main volcanic islands, Mayotte, Moheli, Anjouan and Grand Comore, situated between Mozambique and Madagascar. They have been inhabited since the fifth century, so human-induced environmental change has continued for the last 1.5 millennia. Despite this, 146 species have been recorded, of which 14 endemic species and subspecies of bird survive, albeit some are very rare, and they are mainly concentrated in the remnant forests. The birds have strong biogeographical connections with Madagascar and Africa, and only one species, Homblot’s FlycatcherHumblotia flavirostris, belongs to an endemic genus. Moheli, the smallest island, still harbours many bird species, most notably four sympatric species of pigeon, unique within the south-west Indian Ocean islands. The birds are easily detected but human disturbance is high. Anjouan is under the greatest threat of encroachment, with almost all of its forests degraded to some degree and even these continue to be cut for firewood. Many of the bird species are confined to the remnant montane forests and are only viewable after steep hikes. Grand Comore is the largest and youngest island, and its main volcano, Mount Karthala, boasts one of the largest active craters in the world. Most of the endemic birds are concentrated around the crater, and after a long hike it is possible to see most birds comparatively easily in the stunted forests. Unlike the other islands, which are a United Arab Republic, France administers Mayotte and standards of living are high. It still retains forest and has suffered less human disturbance than the other islands, despite good roads, and most of the birding areas are reached easily. Other than Mayotte, the Comoros have lagged behind in terms of tourism, are poverty stricken, and logistically difficult to travel around, not only between islands, but intra-island as well. The remaining forests are under extreme pressure from human encroachment, thus the long-term future of the avifauna is unfortunately rather tenuous.

26 January 2010: Conserving the Northern Bald Ibis Geronticus eremita — what’s being done to halt centuries of decline in Morocco, Syria, Turkey and elsewhere — Chris Bowden

The historical range and significance of Northern Bald Ibis (NBI) starts in ancient Egypt where it had special significance and its own hieroglyphic symbol, and some recent work suggests it may already have been declining four thousand years ago. Its disappearance was better documented from the European Alps over four hundred years ago, and since 1900, the range contraction has continued from North Africa and the Middle East, largely due to habitat changes, but most sharply since the 1950s when DDT and probably hunting caused extinction in the wild from Turkey (in 1989) and all but two of the fifty Moroccan colonies that were present around 1900. The discovery that 3 relict pairs were still present in Syria in 2002 was a welcome surprise, but the one hundred pairs persisting in Morocco at two coastal sites means they are still classified as Critically Endangered by BirdLife and IUCN.

The feeding habitat is essentially open steppe and unintensive agricultural fields, and the diet a very wide range of invertebrate and small vertebrate prey (lizards in particular), for which they search by probing sandy soils or rocky, shrubby landscapes. There is a further breeding habitat requirement which is ledges on inaccessible cliff faces which do need to be within 20km of extensive areas of feeding habitat. It is a highly social species, usually breeding and foraging in groups, and in the non-breeding period can congregate even further making them potentially vulnerable to one-off events. It has a more complex social system than most birds, relying on learning a higher proportion of its behaviour and movements than other species.

The Moroccan population, having been reduced to such a localised population was thankfully afforded considerable protection when the Moroccan Government declared the Souss-Massa National Park near Agadir in southern Morocco in 1991, and the boundary of the park includes most of the feeding and breeding cliffs. RSPB research started soon after in 1994 to identify and refine actions needed to conserve the species. A key element has been recruitment and training of seven local wardens now managed by the National Park staff. Appointed from adjacent villages they monitor the birds, help prevent disturbance by fishermen and tourists, and informally interact with local communities to inform them why this is important. More specific interventions arising from the research have been the provision of safe fresh-water drinking points which were demonstrated to improve breeding productivity, as well as very occasional predator control. Systematic data collected on the areas used for foraging has been crucial for securing the protection of some key areas otherwise threatened with development for mass tourism facilities. Although such pressures continue to mount and will require ongoing attention, another related piece of work demonstrated that it is fallow areas left uncultivated for two or more years that support far higher lizard populations, and so maintaining this unintensive system may well be key to the long term survival of the ibis population in the area. This is where work by the National Park with ongoing support from Spanish BirdLife Partner SEO is of further key importance. Half of the ibis population breeds nearby outside the National Park, at Tamri, and this area is urgently in need of greater protection.The population was just 59 breeding pairs in 1997, following a mystery die-off, but had increased to 108 pairs by 2009 largely thanks to some of the above measures.

The Eastern population winters in Ethiopia, as revealed in detail by recent satellite tracking of the Syrian breeding birds, whilst the Moroccan birds are much more sedentary. Learning more about the route and causes of mortality has already raised the alarm that hunting along the migration route may well be a key reason for recent declines and urgently needs to be addressed.

There are important semi-wild (Turkey) and zoo (mainly European zoos) populations which are actually far more numerous than the wild birds. At Birecik in Turkey these birds are free-flying for half of the year, and recent release trials have shown promising signs that they may potentially be used to re-establish wild populations, and even be used to supplement the precariously small Syrian population. Other release trials in Austria and Spain have advanced our understanding of how releases may be useful in future, following several early trials (eg in Israel, Italy) that had proved that this is far from straightforward, as they were completely unsuccessful.

An international group, (International Advisory Group for Northern Bald Ibis – IAGNBI) established in 1999 has successfully helped to channel efforts and resources, more recently through input to an International Species Action Plan. By involving key expertise which represents the diverse interest groups and range state governments, and most recently through www.iagnbi.orgwebsite where reports and priorities are readily available, there is now coordinated guidance available to potentially help the species improve its still precarious status.