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Habitat availability for Afrotropical waterbirds is highly dynamic with unpredictable rainfall patterns and ephemeral wetlands resulting in diverse movement strategies among different species. Movement strategies among waterfowl encompass resident, regional and intercontinental migrants, but little quantitative information exists on their specific movement patterns. We studied the movement ecology of five Afrotropical waterfowl species marked with satellite transmitters in Malawi, Mali and Nigeria. Resident species, including White-faced Whistling Ducks Dendrocygna viduata, Fulvous Whistling Ducks Dendrocygna bicolor and Spur-winged Geese Plectropterus gambensis, remained sedentary during the rainy season and only flew limited distances during other months. In contrast, Knob-billed Ducks Sarkidiornis melanotos made short regional movements >50 km in all months and showed little site fidelity to previously used habitats in subsequent years. Garganey Anas quequedula followed an intercontinental strategy and made long-distance jumps across the Sahara and Mediterranean to their Eurasian breeding grounds. Most species flew farthest during the dry season, as mean daily movements varied from 1.5 to 14.2 km and was greatest in the winter months (January–March). Total distance moved varied from 9.5 km for White-faced Whistling Ducks (October–December) to 45.6 km for Knob-billed Ducks (April–June). Nomadic behaviour by Knob-billed Ducks was evidenced by long exploratory flights, but small mean daily movements suggested that they were relying on previous experience. Improving our understanding of these movement strategies increases our ability to assess connectivity of wetland resources that support waterfowl throughout their annual cycle and focuses conservation efforts on their most important habitats.Keywords: migration, nomadism, Sahel, satellite telemetry, sub-Saharan, waterfowl, wetlands

Species that show obvious population declines are relatively easy to categorize as globally threatened under IUCN Red List criteria. However, species whose populations are highly concentrated at a few inaccessible sites that are unprotected or habitat-threatened and then disperse are more difficult to pigeon-hole. Here we re-assess the conservation status of one such species – the Chestnut-banded Plover Charadrius pallidus – that occurs across Africa in specialized, inaccessible and arid habitat. Wetland bird counts from 1991 to the present allow us to determine a new world population estimate of about 17,830 birds. This allows us to determine a new 1% level and we identified only eight sites in southern and East Africa where these plovers congregate in numbers >1% when non-breeding. There are only five other sites that hold more than 100 birds, indicating that the species is not simply widely dispersed across suitable habitats. Simultaneous counts across southern and East Africa indicate that just three sites – Walvis Bay and Sandwich Harbour in Namibia and Lake Natron in Tanzania – can hold 87% of the world population during non-breeding periods. Since two of these sites are under threat from pollution, siltation and water abstraction, and the eight sites in total comprise just 30% of the area criteria set by IUCN, the bird meets one of the two qualifiers for globally Vulnerable status. Despite this, we cannot detect any long-term declines in population size, partly because of wide variations in population numbers over decadal time periods (itself an IUCN qualifier). It is clear that this bird should move from its present Least Concern status to Near Threatened and conservation measures be enacted at two of the top three sites – Walvis Bay and Lake Natron.

The inland delta of the Niger, a vast floodplain, is the only refuge of Black Crowned Cranes in Mali. This study, centred on the regions of Mopti, Tenenkou and Youwarou, aimed to: (1) census the number of cranes in the delta and in captivity in the towns of Mopti and Bamako; (2) examine exploitation at different levels (local and national) to estimate the number of birds captured and traded, and the sums of money involved; and (3) to set up a plan for the conservation of the species. From April to August 2001 a survey was conducted amongst the hunters, buyers, sellers and those holding cranes in the towns of Mopti and Bamako. In these towns 55 people, most of whom had kept and raised cranes for more than 15 years, had 129 Black Crowned Cranes in captivity. Dealing in cranes is an activity restricted to men (farmers, aviculturalists, fishermen and traders). Over the period 1998–2000, 165 birds were bought and sold, while 70 had been exported to other countries. The average purchase price from a hunter was €24. In the delta the selling price was on average 36 278FCFA (francs of the African Financial Community) (€55), whereas in the towns the price was 104 778FCFA (€159) over the same time period. All trophies from the hunt were also sold. Clearly, the survival of this species is threatened both by habitat destruction and by hunting. Under captive conditions the birds do not breed and continued captures could lead to the extinction of cranes in Mali. A plan for the protection of the species has been drawn up and financial support is now being sought. Le Delta Intérieur du Niger (DIN), vaste plaine d'inondation est le seul sanctuaire des Grues couronnées au Mali. C'est dans cette zone de refuge, que l'étude sur «le statut de la Grue couronnée et surexploitation au Mali» a été menée, principalement dans les cercles de Mopti, Tenenkou et Youwarou. Le District de Bamako (capitale du Mali), considérée comme la plaque tournante de toutes les transactions commerciales (achat, vente, et exportation) a été aussi enquêtée. L'étude avait les objectifs suivants: Inventorier les effectifs de Grue couronnée dans le DIN et en captivité dans les villes de Mopti et Bamako en vue de déterminer son statut de protection;Etudier la filière d'exploitation à différentes échelles (local et national) en vue d'une estimation des effectifs capturés, achetés et vendus et des revenus monétaires obtenus;Proposer un plan d'action et sa mise en oeuvre en faveur de la Grue couronnée. Pendant la période d'Avril–Août 2001, une enquête a été menée dans les cercles ci-dessus cités auprès des chasseurs, acheteurs et vendeurs. La même enquête a été menée dans les villes de Mopti et Bamako auprès des éleveurs à domicile et des commerçants. Dans les villes de Mopti et Bamako, 55 éleveurs détiennent en captivité 129 Grues couronnées et se sont les hommes qui élèvent ses oiseaux dans leur basse-cour. La plupart d'entre eux ont plus d'une quinzaine d'années dans cet élevage. La commercialisation de la Grue couronnée est une activité pratiquée seulement par les hommes (agriculteurs, éleveurs, pêcheurs, commerçants). 165 individus vivants ont faits de transactions commerciales (achat/vente) pendant la période 1998-2000 et 70 individus ont été enregistrés à l'exploitation vers les pays Africains, Arabes et Européens. Le prix moyen à l'achat est €24/individu entre les mains des chasseurs. Les prix moyens à la vente sont respectivement de 36278FCFA (€55)/individu, sur le DIN (période 1998–2000), Mopti, Tenenkou et Youwarou contre 104 778FCFA (€159) en villes, communes II, III et IV, pour la même période. Toutes les trophées de l'oiseau sont aussi vendues. Il est apparu les contraintes suivantes à la survie de cette espèce: la disparition et la dégradation de son habitat et la chasse. Dans les conditions actuelles de captivité l'oiseau ne se reproduit pas et la conséquence pourrait être son extinction au Mali. Wetlands International, la DRCN/Mopti et d'autres ONGs ont élaborés un plan d'action en faveur de la protection de l'espèce dont la mise en oeuvre est présentement l'objet de recherche des financements. Ostrich 2007, 78(2): 195–203

Waterbirds in Africa have developed diverse strategies to exploit the wide variety of African wetlands. Whilst some species are largely sedentary, especially those in relatively static tropical climates, most demonstrate movements in response to changing seasons and environmental conditions. The onset of rain is an important trigger for migration: some waterbirds are harbingers of the rainy season, whilst others follow in the wake of rain. However, levels and timing of rain can be unpredictable and rain may not fall at all some years. When rain falls in arid and semi-arid areas, productive temporary wetlands can appear rapidly and attract large numbers of waterbirds, many of which are partially nomadic. This unpredictability presents difficult management scenarios. Overall, waterbird movements within Africa are poorly understood, which limits our abilities to conserve waterbirds in Africa and to implement the African-Eurasian Migratory Waterbird Agreement. It will take major resources and many years before we have clear pictures of waterbird movements within Africa. Influencing factors such as climate change and wetland degradation may well lead to further changes in migratory patterns. Nevertheless, conservation measures are required immediately, especially for declining species. Ostrich 2007, 78(2): 149–154

(2014). Birds in a Changing Environment: Report on the 13th Pan-African Ornithological Congress in Arusha, Tanzania. Ostrich: Vol. 85, No. 1, pp. iii-vi.

Dodman, T. & Rose, P. 2000. Distribution and abundance of African waterfowl: examples from the African Waterfowl Census. Ostrich 71 (1 & 2): 235–243. Wetlands International coordinates waterfowl counts in Africa. Counts from 1958–1990 were analysed in 1991, when the African Waterfowl Census (AfWC) was also launched. By 1996, 25 countries were participating. This preliminary appraisal of the AfWC shows that resulting data can be used to identify distribution and abundance patterns, although there are still significant gaps in AfWC coverage and focus. The degree to which AfwC data may be used to assess the conservation status of African waterfowl populations depends on a function of data quality, quantity and reliability. To enable this practical use of data, several priorities for future work are identified, based on the strengths and weaknesses of the current information: (1) simultaneous co-ordinated counts, (2) regular annual or biannual monitoring of the same sites, (3) development of priority list of ...

Dodman, T., Katanekwa, V., Aspinall, D. & Stjernstedt, R. 2000. Status and distribution of the Black-cheeked Lovebird, Zambia. Ostrich 71 (1 & 2): 228–234. A survey of the Black-cheeked Lovebird Agapornis nigrigenis in 1994 resulted in much new information. About 10 000 live in mopane Colophospermum mopane woodland in south-west Zambia. They are localised with a high dependence on mopane woodland with permanent standing water. Some birds may also occur in the eastern part of Namibia's Caprivi strip, in the northern tip of Botswana and in the western tip of Zimbabwe. However, its status here is confused by the presence of feral lovebirds of more than one species. The core distribution is a disjointed belt of mopane woodland between the Zambezi and Kafue rivers. The distribution outside the dry season is wider and allied to the availability of ripening crops close to patches of mopane woodland or riverine forest. The total area of mopane woodland utilised is approximately 4 550 km2. The habitat is dynamic, ...

International audience; Heterogeneity in the transmission rates of pathogens across hosts or environments may produce disease hotspots, which are defined as specific sites, times or species associations in which the infection rate is consistently elevated. Hotspots for avian influenza virus (AIV) in wild birds are largely unstudied and poorly understood. A striking feature is the existence of a unique but consistent AIV hotspot in shorebirds (Charadriiformes) associated with a single species at a specific location and time (ruddy turnstone Arenaria interpres at Delaware Bay, USA, in May). This unique case, though a valuable reference, limits our capacity to explore and understand the general properties of AIV hotspots in shorebirds. Unfortunately, relatively few shorebirds have been sampled outside Delaware Bay and they belong to only a few shorebird families; there also has been a lack of consistent oropharyngeal sampling as a complement to cloacal sampling. In this study we looked for AIV hotspots associated with other shorebird species and/or with some of the larger congregation sites of shorebirds in the old world. We assembled and analysed a regionally extensive dataset of AIV prevalence from 69 shorebird species sampled in 25 countries across Africa and Western Eurasia. Despite this diverse and extensive coverage we did not detect any new shorebird AIV hotspots. Neither large shorebird congregation sites nor the ruddy turnstone were consistently associated with AIV hotspots. We did, however, find a low but widespread circulation of AIV in shorebirds that contrast with the absence of AIV previously reported in shorebirds in Europe. A very high AIV antibody prevalence coupled to a low infection rate was found in both first-year and adult birds of two migratory sandpiper species, suggesting the potential existence of an AIV hotspot along their migratory flyway that is yet to be discovered.

Despite considerable effort for surveillance of wild birds for avian influenza viruses (AIVs), empirical investigations of ecological drivers of AIV prevalence in wild birds are still scarce. Here we used a continental-scale dataset, collected in tropical wetlands of 15 African countries, to test the relative roles of a range of ecological factors on patterns of AIV prevalence in wildfowl. Seasonal and geographical variations in prevalence were positively related to the local density of the wildfowl community and to the wintering period of Eurasian migratory birds in Africa. The predominant influence of wildfowl density with no influence of climatic conditions suggests, in contrast to temperate regions, a predominant role for inter-individual transmission rather than transmission via long-lived virus persisting in the environment. Higher prevalences were found in Anas species than in non- Anas species even when we account for differences in their foraging behaviour (primarily dabbling or not) or their geographical origin (Eurasian or Afro-tropical), suggesting the existence of intrinsic differences between wildfowl taxonomic groups in receptivity to infection. Birds were found infected as often in oropharyngeal as in cloacal samples, but rarely for both types of sample concurrently, indicating that both respiratory and digestive tracts may be important for AIV replication.

We provide recommendations for implementing telemetry studies on waterfowl on the basis of our experience in a tracking study conducted in three countries of sub-Saharan Africa. The aim of the study was to document movements by duck species identified as priority candidates for the potential spread of avian influenza. Our study design included both captive and field test components on four wild duck species (Garganey, Comb Duck, White-faced Duck and Fulvous Duck). We used our location data to evaluate marking success and determine when signal loss occurred. The captive study of eight ducks marked with non-working transmitters in a zoo in Montpellier, France, prior to fieldwork showed no evidence of adverse effects, and the harness design appeared to work well. The field study in Malawi, Nigeria and Mali started in 2007 on 2 February, 6 February and 14 February, and ended on 22 November 2007 (288 d), 20 January 2010 (1 079 d), and 3 November 2008 (628 d), respectively. The field study indicated that 38 of 47 (81%) of the platform transmitter terminals (PTTs) kept transmitting after initial deployment, and the transmitters provided 15 576 locations. Signal loss during the field study was attributed to three main causes: PTT loss, PTT failure and mortality (natural, human-caused and PTT-related). The PTT signal quality varied by geographic region, and interference caused signal loss in the Mediterranean Sea region. We recommend careful attention at the beginning of the study to determine the optimum timing of transmitter deployment and the number of transmitters to be deployed per species. These sample sizes should be calculated by taking into account region-specific causes of signal loss to ensure research objectives are met. These recommendations should be useful for researchers undertaking a satellite tracking program, especially when working in remote areas of Africa where logistics are difficult or with poorly-known species.OSTRICH 2011, 82(1): 17–26

There have been recent advances in estimating the size and status of waterbird populations at the global level. The main objectives of this process are to assist in identifying Wetlands of International Importance under the Convention on Wetlands, to identify conservation and research priorities in order to maintain global waterbird biodiversity, to identify gaps in knowledge, and to support the development of the Conventions on Wetlands, Migratory Species and Biological Diversity. Significant advances were made in reviewing and developing new estimates for waterbird populations occurring in Africa, in preparation for Waterbird Population Estimates (third edition), which was published in 2001. Estimates have now been made for over 80% of waterbird populations in Africa. The process is ongoing and depends upon the input of many contributors and on reviews of published materials and unpublished reports. This paper presents a review of the sizes, overall status and trends of waterbird populations in Africa, and provides generic recommendations for monitoring populations and improving their conservation status. Ostrich 2007, 78(2): 475–480

Of the six species of cranes occurring in Africa, the Black Crowned Crane ( Balearica pavonina ) is Near-threatened, the Wattled Crane ( Grus carunculatus ) and Blue Crane ( Anthropoides paradiseus ) are Vulnerable, the Grey Crowned Crane ( B. regulorum ) is rapidly declining, and the Atlas Mountain population of Demoiselle Crane ( A. virgo ) may be Extinct. Over the past decade, intensive coordinated surveys have resulted in significant revisions to the population estimates for Africa's cranes. The total population of Wattled Crane, previously estimated at 13 000–15 000 birds, now numbers less than 8 000 individuals and the species is in decline in as many as nine of 11 countries in its range. The B. p. pavonina population is highly fragmented and has been reduced to approximately 15 000 birds, whilst it is likely that the B. p. ceciliae population is also in decline. The East African population of Grey Crowned Crane ( B. r. gibbericeps ) has been reduced to 43 000–55 000 birds, an almost 50% decline in the past 20 years. The estimated population of Blue Cranes (>25 580) reflects a slight increase over previous estimates but is substantially lower than historical levels. Crane numbers are seriously affected by degradation and disturbance of breeding grounds and capture for domestication and trade. Ostrich 2007, 78(2): 175–184

Background Virological, molecular and serological studies were carried out to determine the status of infections with avian influenza viruses (AIV) in different species of wild waterbirds in Iran during 2003-2007. Samples were collected from 1146 birds representing 45 different species with the majority of samples originating from ducks, coots and shorebirds. Samples originated from 6 different provinces representative for the 15 most important wintering sites of migratory waterbirds in Iran. Results Overall, AIV were detected in approximately 3.4% of the samples. However, prevalence was higher (up to 8.3%) at selected locations and for certain species. No highly pathogenic avian influenza, including H5N1 was detected. A total of 35 AIVs were detected from cloacal or oropharyngeal swab samples. These positive samples originated mainly from Mallards and Common Teals. Of 711 serum samples tested for AIV antibodies, 345 (48.5%) were positive by using a nucleoprotein-specific competitive ELISA (NP-C-ELISA). Ducks including Mallard, Common Teal, Common Pochard, Northern Shoveler and Eurasian Wigeon revealed the highest antibody prevalence ranging from 44 to 75%. Conclusion Results of these investigations provide important information about the prevalence of LPAIV in wild birds in Iran, especially wetlands around the Caspian Sea which represent an important wintering site for migratory water birds. Mallard and Common Teal exhibited the highest number of positives in virological and serological investigations: 43% and 26% virological positive cases and 24% and 46% serological positive reactions, respectively. These two species may play an important role in the ecology and perpetuation of influenza viruses in this region. In addition, it could be shown that both oropharyngeal and cloacal swab samples contribute to the detection of positive birds, and neither should be neglected.