Haliaeetus Vociferoides Research Articles

Madagascar Fish Eagle productivity in the Tsimembo-Manambolomaty Protected Area and surrounding habitat of western Madagascar

We monitored the productivity of the critically endangered Madagascar Fish Eagle Haliaeetus vociferoides inside and outside of the Tsimembo-Manambolomaty Protected Area (T-M PA), western Madagascar from 2010 to 2015. We recorded 14 breeding pairs inside and 13 outside T-M PA. The T-M PA and surrounding habitat hosted respectively 10 and six breeding polyandrous pairs, composed of one adult female and two adult males. During the six-year study period, 101 eggs were laid in nests in T-M PA of which 60 hatched and 58 young fledged. We recorded 62 eggs laid in nests outside the T-M PA of which 39 hatched and 36 young fledged. Productivity was similar at both sites, inside and outside T-M PA, with 0.84 (58/69) and 0.76 (36/47) fledgling per nesting attempt and 0.69 (58/84) and 0.5 (36/72) fledglings per territorial pair, respectively. Polyandrous pairs have higher productivity compared with normal pairs. Threats to Madagascar Fish Eagles and their habitat were low due to the existence of a community-based resource management system called the Local Management Secured System (GELOSE) inside and outside the T-M PA. This system is based on strengthening local traditional customs and rules, and involving local people in managing their natural resources sustainably along with biodiversity conservation.

Population status of the Madagascar Fish EagleHaliaeetus vociferoidesin 2005–2006

SummaryCoastal and inland surveys for the endemic and “Critically Endangered” Madagascar Fish EagleHaliaeetus vociferoideswere conducted in western Madagascar from Antsiranana in the north to Manja in the south during the 2005 and 2006 breeding seasons (May–October). Surveys covered typical Madagascar Fish Eagle habitat: lakes, rivers, mangroves, estuaries, and marine islands within their known distribution. In total, 287 individuals were encountered, including 98 breeding pairs (196 individuals), 23 breeding trios (69 individuals), 15 single adults and seven immature birds. Of these 287 birds, 128 individuals (44.6%) were observed on lakes; 116 (40.4%) in coastal areas, consisting of 103 (35.9%) in mangroves and 13 (4.5%) in estuaries; 32 (11.2%) on marine islands and 11 (3.8%) on rivers. There was an increase between surveys in 1995 and this study in the number of Madagascar Fish Eagles counted, from 222 to 287, and in the number of pairs from 99 to 121. This study confirms that the Madagascar Fish Eagle population is still low due to human persecution (hunting, collection of eggs and nestlings), overfishing and habitat destruction. We recommend monitoring fish eagles annually at the higher concentration sites to evaluate human activities and conducting a population survey every five years throughout western and northern Madagascar.

Protected area surface extension in Madagascar: Do endemism and threatened species remain useful criteria for site selection ?

The ‘hotspot approach’ considers that endemism and threatened species are key factors in protected area designation. Three wetland and forest sites have been proposed to be included into Madagascar’s system of protected areas (SAPM – Systeme des Aires Protegees de Madagascar). These sites are Manambolomaty (14,701 ha) and Mandrozo (15,145 ha) in the west and Bemanevika (37,041 ha) in the north. Biodiversity inventories of these three sites recorded 243 endemic species comprised of 44 reptiles, 54 amphibians, 104 birds, 23 small mammals, 17 lemurs and one fish. Of these 243 species, 30 are threatened taxa comprising two Critically Endangered (CR), 11 Endangered (EN) and 17 Vulnerable (VU) species. The long term ecological viability of these sites has been shown by population stability of the two Critically Endangered flagship species, the Madagascar fish eagle (Haliaeetus vociferoides) in Manambolomaty and Mandrozo and the recently rediscovered Madagascar pochard (Aythya innotata) in Bemanevika. Other threatened species and high biological diversity also justifies their inclusion into Madagascar’s SAPM.

Taboos and social contracts: Tools for ecosystem management – lessons from the Manambolomaty Lakes RAMSAR site, western Madagascar

Traditional taboos and social contracts played an important role in managing the Manambolomaty RAMSAR site. Taboos are defined as a prohibition imposed by social custom as a protective measure’ and social contracts are – in conservation sense – a common agreement for achieving conservation, sustainable development and development of resources objectives. The Manambolomaty Lakes RAMSAR site, District of Antsalova in western Madagascar, is composed of four lakes (Soamalipo, Befotaka, Ankerika and Antsamaka) surrounded by the Tsimembo deciduous forest. The first three lakes with forest surrounding encompass 14,701 ha and are being managed by two local Associations: FIZAMI (FIkambanana Zanatany Andranobe MIray) and FIFAMA (FIkambanana FAmpandrosoana Mamokatra Ankerika). The associations have used traditional taboos and social conventions to manage their local natural resources by incorporating a GELOSE (GEstion Locale SEcurisée) management system to conserve biological diversity, maintain resource sustainability and socio - economic viability. This site has the highest concentration of the endemic and critically endangered Madagascar fish eagle (Haliaeetus vociferoides), representing 10 % of the global population, and many other species of different faunal groups are also in good conservation status such as Decken’s sifaka (Propithecus deckeni) and Western lesser bamboo lemurs (Hapalemur occidentalis) and Madagascar flying fox (Pteropus rufus). Culturally, the site is known as a unique source of the endemic tree Hazomalania voyroni (Hernandiaceae), which is used by the Sakalava people for constructing coffins, and being buried in a coffin made of this wood is a great honour for the Sakalava people. From Manambolomaty’s Lakes fish yields, estimated at 60 - 100 tons per fishing season, FIZAMI and FIFAMA are one of the few Malagasy Associations with active bank accounts supported by management of their natural resources and associated activities. Their fisheries management system has increased the annual local revenue estimated at more than $ 1,562 US / fisherman per season. The tax of fish sales to wholesale fish buyers forms 56 % of the two local Commune’s budgets. This has made the Community - Based Wetlands Conservation at the Manambolomaty Lakes site well known in the conservation circles within Madagascar and has been modelled vy other organizations and associations. Consequently, the Manambolomaty Lakes site is in the process of being added into the System of Protected Areas of Madagascar (SAPM) (Figure 1).

Long‐term survival despite low genetic diversity in the critically endangered Madagascar fish‐eagle

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape.

Isolation of 22 newHaliaeetusmicrosatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three otherHaliaeetuseagle species

We isolated a total of 22 microsatellite loci from two Haliaeetus species: the Madagascar fish-eagle (Haliaeetus vociferoides) and the bald eagle (Haliaeetus leucocephalus). Five loci were monomorphic in both the Madagascar fish-eagle (n = 24–43) and the bald eagle (n = 2–8) but were found to be polymorphic in other Haliaeetus species. Haliaeetus loci have proved useful for investigating gene flow in Haliaeetus and Aquila eagles. Ten loci were polymorphic in the critically endangered Madagascar fish-eagle and will be used to investigate the genetic population structure and mating system in this species.

Isolation of 22 new Haliaeetus microsatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three other Haliaeetus eagle species

Isolation of 22 new Haliaeetus microsatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three other Haliaeetus eagle species

Using Molecular Sexing to Assess Field-based Sexing Techniques in the Madagascar Fish-Eagle

Uso De Metodos Moleculares Para Evaluar Las Tecnicas De Campo Para Determinar El Sexo En Haliaeetus vociferoides Las tecnicas de campo para determinar el sexo de individuos adultos de la especie Haliaeetus vociferoides han incluido datos del peso corporal, la frecuencia de las vocalizaciones y la posicion durante la copula. Pusimos a prueba la confiabilidad de dichas tecnicas empleando metodos moleculares de determinacion del sexo en 43 individuos marcados. Demostramos la confiabilidad del uso del peso corporal y las frecuencias de las vocalizaciones para determinar el sexo con exactitud en el campo, y la poca confiabilidad del uso de la postura durante la copula. [Traduccion del equipo editorial]

Sakalava fishermen and Madagascar Fish Eagles: enhancing traditional conservation rules to control resource abuse that threatens a key breeding area for an endangered eagle

Watson, R.T. & Rabarisoa, R. 2000. Sakalava fishermen and Madagascar Fish Eagles: enhancing traditional conservation rules to control resource abuse that threatens a key breeding area for an endangered eagle. Ostrich 71 (1 & 2): 2–10. Survival of the Madagascar Fish Eagle is threatened by human persecution and habitat loss. Of a global Madagascar Fish Eagle population estimated at 100 breeding pairs, the single most important concentration often pairs breeds on three adjacent lakes near the southern end of the species' range along the western seaboard of Madagascar. Fishing on the lakes is the main livelihood of local Sakalava tribespeople who have harmoniously shared these important wetlands with fish eagles for centuries. In the last five years Peregrine Fund researchers have documented a massive influx of up to 275 seasonal migrant fishermen who abuse local traditional resource extraction rules. The economic incentive to endure the hardship of migration to the lakes and camping on the lakeshore for the season is strong. In 1995 per-capita income from fishing was about $1 500 for the six month season, 7.5 times the national annual average. Fish stocks were rapidly diminished through the fishing season as catches diminished to the point where fishermen gave up fishing before the end of the season. The resilience of introduced Tilapia sp. has so far ensured that stocks rebounded between fishing seasons. Fish stocks were at their lowest when Madagascar Fish Eagle nestlings fledged. The most serious impact of fishermen may be on the lake-side forest, which was used as a source of dugout canoes and wood to fuel fish-drying fires. Up to 275 trees were cut for canoes in 1995 and up to 90 wood fires burned for a total of about 111 500 hours to dry a catch of almost 6.9 million fish. To conserve this important breeding site we aim to prevent loss of fish eagle nesting habitat, increased nest site disturbance, and reduced prey availability by working with community members and local leaders to enforce traditional resource use rules and find alternatives to unsustainable forms of resource extraction. Watson, R.T. & Rabarisoa, R. 2000. Pêcheurs Sakalava et Aigles pêcheurs de Madagascar: relancer les règles traditionelles pour contrôler l'abus de ressources menaçant la zone clé de reproduction d'un aigle en danger. Ostrich 71 (1 & 2): 2–10. La survie de la Pygargue de Madagascar est menacée par la persecution humaine et la perte de l'habitat. A l'intérieur d'une population globale estimée à 100 couples reproductifs, la seule concentration importante rassemble 10 couples se reproduisant au niveau de trois lacs adjacents situés près de l'extrémité sud de l'aire de distribution de l'espèce, qui longe la zone côtière ouest de Madagascar. La pêche sur les lacs est la principale source de subsistance de la tribu Sakalava qui a su vivre en harmonie avec les aigles en partageant ces milieux humides d'importance considérable au fil des siècles. Au cours de ces cinq dernières années, l'équipe du Peregrine Fund a enregistré une migration massive de plus de 275 pêcheurs saisonniers violant les règies traditionnelles d'exploitation. Les lacs exercent un tel attrait économique que les difficultés de la migration et les conditions de campement au bord du lac sont endurées. En 1995, le revenu foumi par la pêche était de $1 500 pendant les six mois de la saison, soit 7.5 fois la moyenne annuelle de revenue. La régénération de l'espèce introduite Tilapia sp. assurait la récrudescence du stock de poisson entre les saisons. Ce stock de poisson a connu une décroissance rapide durant la saison, la diminution du produit a poussé les pêcheurs à abandonner la pêche avant la fin de la saison. Le stock était au plus bas au moment oú les jeunes aigles commençaient à voler. L'impact de l'existence de pécheurs apparaît plus sérieusement au niveau des forêts autour du lac, qui sont sollicitées comme source de pirogues et de combustible pour le séchage du poisson àfumer. En 1995, plus de 275 arbres ont été abattus et plus de 90 feux de bois ont brûlé pendant une période totale de 111 500 heures pour faire sécher 6.9 millions de poissons. Assurer la conservation de cet important site de reproduction requiert la prévention contre la perte ou la perturbation du lieu de nidification de l'Aigle pêcheur, et contre la diminution de la disponibilité du poisson. Nous collaborons dans ce sens avec les membres de la communauté et les responsables locaux afin de renforcer les règles d'utilisation des ressources et trouver des alternatives concernant leur exploitation informelle.

Description of nesting and foraging habitat of the Madagascar Fish-eagle Haliaeetus vociferoides: a conservation initiative

Watson R.T., Berkelman J., Rabarisoa R., Thorstrom R., & Watson C.R.B. 2000. Description of nesting and foraging habitat of the Madagascar Fish-Eagle Haliaeetus vociferoides: a conservation initiative. Ostrich 71 (1 & 2): 336–340. Recent surveys indicate the Madagascar Fish-Eagle Haliaeetus vociferoides population is about 100 breeding pairs; the species is considered among the most endangered birds of prey worldwide. This paper reports one of several studies to determine the causes of the species' rarity so that an effective species survival plan can be implemented. Nesting and foraging habitat parameters including nest, nest tree, surrounding vegetation, and adjacent water parameters, were measured at 56 nests found along the western seaboard of Madagascar. Descriptive statistics were used to look for consistent patterns among habitat parameters. While certain trends were apparent, such as always nesting within sight of water and in the largest trees, there was little evidence that would suggest negative human impact on nest site or foraging habitat availability for this species wherever large trees and water ecotones remain, yet many such sites are unoccupied. Conservation of water-forest ecotones in western Madagascar is a high priority for the survival of this species, but wider conservation measures are needed to address direct human interference and additional study is needed to fully understand habitat limitation and other possible causes of the species' rarity. Watson R.T., Berkelman J., Rabarisoa R., Thorstrom R., & Watson C.R.B. 2000. Description du site de nidification et de chasse de I'Aigle pkheur de Madagascar Haliaeehrs vociferoides: une initiative de conservation. Ostrich 71 (1 & 2): 3 3 6 340.

Lake Selection by Madagascar Fish-Eagles

We investigated fish abundance and habitat characteristics at 32 lakes occupied by Madagascar Fish-Eagles (Haliaeetus vociferoides) and 32 randomly selected unoccupied lakes between Morondava and Boriziny in western Madagascar from May to November 1995. We measured lake and shoreline habitat characteristics and used gill nets to sample fish populations. Compared with unoccupied lakes, lakes occupied by fish-eagles were deeper and clearer, had more shoreline perch trees, and yielded gill-net catches with more fish, a higher total fish mass, and more fish species. A logistic regression model with number of shoreline perch trees and number of fish species caught in gill nets as independent variables correctly classified fish-eagle use for 76.6% of the lakes in the study. A model with number of shoreline perch trees alone was 71.9% accurate, suggesting that perch-tree availability is the most important factor limiting populations of Madagascar Fish-Eagles. The results indicate that Madagascar Fish-Eagles require bodies of water with large shoreline trees and ample populations of fish.

Breeding biology, extra-pair birds, productivity, siblicide and conservation of the Madagascar Fish Eagle

Watson, R.T., Razafindramanana, S., Thorstrom & Rafanomezantsoa, S. 1999. Breeding biology, extra-pair birds, productivity, siblicide and conservation of the Madagascar Fish Eagle. Ostrich 70 (2): 105–111. Madagascar Fish Eagles Haliaeetus vociferoides laid eggs over a 53-day period from the end ofMayto mid-July. The incubation period ranged from 37 to 43 days with a mean of 39.7 days and 95% confidence interval of ± 2.3 days. Eggs hatched over a 46-day period from 5 July to 20 August with a mean hatch date of 23 July, and a 95% confidence interval of 18 to 28 July. Nestling periods ranged from 78 to 89 days and averaged 82 days. Mean fledging date was calculated from mean hatching date as 9 to 20 September, with a 95% confidence interval from 31 August to 29 September. Clutch size was determined in 35 cases, of which seven (20%) were single-egg and 28 were two-egg clutches. Productivity from occupied territories was 0.15 fledged young/territory in 65 pair-years. Sibling rescue in three years increased productivity to 0.28 young/territory. Apart from failure to lay eggs, which accounted for 21 of the 55 instances, siblicide accounted for most of the reduced productivity. Human removal of nestlings for food and to keep in captivity accounted for a large proportion of the total breeding failures. The most unusual behaviour observed was the presence of an extra-pair bird in the immediate proximity of a breeding pair in 40 (42%) of 95 pair-years, at 41 nest sites (the status of every pair was not determined every year). Extra-pair birds participated briefly in incubation and nestling-period activities in each of two observed nests. Banding evidence suggests that extra-pair birds are progeny from previous years that have delayed dispersal, but sample size is too small to be conclusive.

Status of the Madagascar Fish Eagle Haliaeetus vociferoides in 1995

Rabarisoa, R., Watson, R.T., Thorstrom, R., & Berkelman, J. 1997. Status of the Madagascar Fish Eagle Haliaeetus vociferoides in 1995. Ostrich 68 (1): 8–12. Surveys for the Madagascar Fish Eagle Haliaeetus vociferoides were conducted each breeding season (May through October) from 1991 through 1995 between Morondava and Antsiranana, western to northwestern Madagascar, to estimate the population size of this endangered species. Suitable habitat including lakes, rivers, estuaries, mangroves, and marine islands was searched and at least 222 adult Madagascar Fish Eagles were observed including 63 breeding pairs, 36 probable pairs, 24 single adults and 18 immature birds. Assuming that all probable pairs were breeding, we estimated the Madagascar Fish Eagle breeding population was 99 pairs (95% confidence interval = 78 to 120) in the area searched. This estimate is about twice the number previously estimated in the period 1980–1985, due mainly, we believe, to our greater search effort, although we cannot discount an increase in the breeding population. The number of breeding pairs has declined since 1985 in some localities, suggesting a population decline or movement of pairs away from these sites. We recommend annual monitoring of a random sample of known breeding pairs until causes for the species' rarity have been limited and no evidence of population decline is detected, followed by monitoring at least every five years until the species can be removed from the endangered list. Rabarisoa, R., Watson, R.T., Thorstrom, R., & Berkelman, J. 1997. Statut du Pygargue de Madagascar Haliaeetus vociferoides en 1995. Ostrich 68 (1): 8–12. De 1991 à 1995, des recherches sur le Pygargue de Madagascar Haliaeetus vociferoides ont été conduites durant chaque saison de reproduction (de mai à octobre) entre Morondava et Antsiranana, dans l'ouest et le nord-ouest de Madagascar. Tous les habitats convenables, y compris lacs, rivières, estuaires, mangroves et îies côtières ont été visités et un total minimal de 222 adultes a été observé, compris de 63 couples reproductifs, de 36 couples potentiels, de 24 adultes solitaires et de 18 immatures. En considérant que tous les couples potentiels se reproduisent, nous estimons la population de Pygargues de Madagascar à environ 99 couples (intervalle de confiance de 95% = 78 à 120) répartis dans la région de la recherche. Ce nombre est presque le double du nombre estimé pendant la période de 1980–1985, ce qui pourrait être dû principalement au temps de recherche mobilisé, quoique nous ne puissions pas escompter une augmentation au niveau de la population reproductive. La diminution du nombre de couples reproductifs dans certaines localités connues précédemment suggère un déclin de la population ou un déplacement des paires loin de ces sites. Nous recommandons des suivis annuels de couples reproductifs pris au hasard jusqu' à ce que les causes de la rareté de l'espèce soient délimitées et jusqu' à ce que il sera évident que la population ne soit pas en déclin.

Survey and management proposals for a tropical deciduous forest reserve at Ankarana in Northern Madagascar

A detailed survey was conducted of the fauna and flora of a Special Reserve in Madagascar. Ankarana is a dramatic limestone massif, dissected by canyons and caves that link areas of isolated forest, some of which have never been visited by man. A rich fauna of endemic Malagasy animals was discovered including only the third population known of the white-breasted mesite Mesitornis variegata, one sighting of the Madagascar fish eagle Haliaeetus vociferoides and at least six species of lemurs. Feeding damage provided evidence for the presence of two more lemurs, the aye-aye Daubentonia madagascariensis and the rare greater bamboo lemur Hapalemur simus. Detailed studies were conducted to ascertain the status of the mesite, crowned lemur Lemur coronatus and Nile crocodile Crocodylus niloticus populations in the reserve. Despite some formidable terrain, the most vital area of deciduous forest is easily accessible via an old logging trail. Forest clearance, poorly controlled grassland fires and free-ranging grazing of livestock are threatening Ankarana. We suggest some management proposals which involve upgrading the Special Reserve to a warden-controlled National Park. Funding could be provided, in part, by developing tourism in the less ecologically vulnerable southern half of the massif, where the scenery is dramatic and the caves are arguably among the most impressive in the world.

Distribution, status and conservation of the Madagascar fish-eagle Haliaeetus vociferoides desmurs 1845

The Madagascar fish-eagle Haliaeetus vociferoides is endemic to Madagascar, ranging over 600 km of the western coast between Antsiranana and Belo sur Mer. It occurs in three different types of biotopes: marine rocky areas; mangroves; and lakes and rivers. Forty-eight occupied sites were recorded between 1982 and 1986, comprising 96 individuals and including 40 pairs and 10 isolated adults. The principal threats to this species are hunting, trapping, and taking young from nests. The existing network of protected areas does not guarantee its survival. Only the establishment of a reserve in the small rocky islands of the North West and the creation of a National Park including the larger lakes in the Antsalova region would ensure the protection of a major population of the fish-eagle.