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The Tooth-billed Pigeon (Didunculus strigirostris) was classified as critically endangered in 2014. A Manumea Recovery Plan 2006–2016 was implemented by the Ministry of Natural Resources and Environment of Samoa (MNRE in Recovery plan for the Manumea or Tooth-billed Pigeon Didunculus strigirostris, Ministry of Natural Resources and Environment, Government of Samoa, Apia, 2006) but the main objectives of the plan could not be achieved because of the difficulty of discriminating between the coo calls of Didunculus strigirostris and those of the Pacific Imperial Pigeon (Ducula pacifia). The study provides key information for field work and training of a national team for monitoring Didunculus populations. The spectrographical and statistical analysis of coo calls of these two species shows significant differences in frequency traits. Calls of Didunculus are slightly higher than those of Ducula. The differences, however, are small and detectable only under optimal conditions. The coo calls show overlap in both pitch and length, so identification by call only in the field is not often possible; laboratory analysis of recordings is usually necessary.

The significance of the role of birds in hominin evolution in Island Southeast Asia is not clear. Few avian vertebrate deposits have been recovered from archaeological or fossil sites in the region, and their association with either hominin or natural deposition in caves and rock shelters complicates their usefulness in hominin behavioural and palaeoecological reconstructions. In this paper, we assess the taphonomic history of the Pleistocene avian vertebrate remains recovered from Laili Cave, Timor-Leste, dated to between ca. 44.6 to 11.2 ka and in association with abundant lithic material. We use avian taxonomic composition, skeletal element abundance, and bone surface modification data to determine the agent of avian skeletal deposition. Our analyses indicate that the small grassland and woodland birds (quail, buttonquail, song birds), which dominate the assemblage, were deposited by avian predators (probably barn owls) throughout the sequence. Humans possibly hunted the small quantity of larger birds (imperial pigeon, duck). The bird remains suggest that grasslands, woodland savannahs, wetlands, and forest environments were present locally during the Pleistocene.

We reconstruct the phylogeny of imperial pigeons (genus Ducula) using mitochondrial and nuclear sequence data. We evaluate the most likely biogeographic scenario for the evolution of this group that colonized many islands of the Pacific Ocean. The divergence time analysis suggests that the basal divergences within Ducula occurred more recently than in the fruit doves (genus Ptilinopus), a group that is also well diversified in Oceania. The imperial pigeons colonized the Melanesian region several times independently, and the diversification within this region led to several species in sympatry, in particular in the Bismarck archipelago. Central Polynesia was also colonized several times, first by a lineage during the Miocene that led to the large D. latrans, sister to the New Caledonian endemic D. goliath, then more recently by the widespread D. pacifica, during the Pleistocene. The phylogenetic pattern obtained with the extant Ducula species showed that the Eastern Polynesian endemics do not form a monophyletic group, with the Pacific Imperial Pigeon D. pacifica sister species with good support to the Polynesian Imperial Pigeon D. aurorae. However, the impact of recent anthropic extinctions has been important for the imperial pigeons, more than for the smaller fruit doves, suggesting that several Ducula lineages might be missing today.

The tooth-billed pigeon (Didunculus strigirostris) is an endemic and highly cryptic bird of the rainforest canopy of Samoa. According to the recently released Tooth-billed Pigeon Recovery Plan (2020–2029), one of the greatest obstacles to conservation efforts is the inability of ornithologists to reliably separate its advertising coo call from that of the common and sympatric Pacific imperial pigeon (Ducula pacifica). Because tooth-billed pigeons are very rarely seen, acoustic methods of identifying them, which have been problematic for ornithologists, would be helpful for population surveys. Our study examines the traditional ecological knowledge and skill of Samoan hunters, peer selected for knowledge and reliability from six villages located on Upolu and Savaii islands, to determine whether they can consistently identify the species based on the calls. Through use of automatic devices, we recorded pigeon coo calls at nine forest sites recommended by reliable hunters within four key biodiversity areas of the islands of Upolu and Savaii from March to June 2016. We isolated and filtered 104 clear coo call sequences from these recordings. The two top hunters separately and confidently identified which of the two pigeon species were calling for 80 of the 104 sequences. On 54 of these 80 call sequences the hunters were in agreement, both assigning a call to the one species. We measured seven sonographic variables on each of the coo calls of each of these 54 sequences in order to investigate potential differences between the calls of Didunculus and Ducula. Two clear differences emerged: a strongly statistically significant difference in the highest frequency of the coo call, and the more regular spacing of the coo calls of Didunculus than of Ducula. Only the second rhythm outcome is consistent with a recent independent analysis by other authors. This regularity of the intervals between coo calls in a sequence may be the key to separation of the two species in the field.

The Pied Imperial-Pigeon (Ducula bicolor) is a summer migrant to northern Australia, and nests colonially on many islands of the Great Barrier Reef, Queensland. Numbers are perceived to have declined as a result of large-scale shooting in the past and clearing of their mainland feeding grounds. To obtain evidence of any population changes, 1–10 counts were made each breeding season of the evening flight from the mainland to a nesting colony on North Brook Island. The counts began in 1965 and have continued for 50 years. The count represents one individual of a pair that visits the mainland to feed and returns in the evening. In the 1965–66 breeding season, the December count (the count used to compare years) was 4692 birds. Over the following three seasons, numbers declined to a low of 1451 birds in 1968–69; this decline was attributed to shooting of up to 1100 birds at a time. Large-scale shooting stopped in 1968 and was followed by a steady exponential increase (y = 3370.4e0.0908x) in numbers over 23 years to 29818 birds in the 1992–93 season. Numbers have fluctuated between ~25000 and 35000 individuals over the following 18 years. A tropical cyclone of extreme intensity affected the pigeons’ breeding site on North Brook Island and their mainland feeding areas in February 2011. In the following breeding season of 2011–12, numbers fell to 5311, but recovered to 21088 in the 2012–13 season. The dramatic drop in numbers was attributed to the pigeons moving elsewhere for the 2011–12 season. It is predicted that the post-cyclonic number of 21088 will take 4 years to recover to 30000. The counts are a simple and somewhat coarse measure of population trends, but provide a population baseline for more sophisticated studies on the movements of pigeons and their responses to long-term changes in habitat and climate.

Present manuscript is the sighting records of two less known individual species of Columbidae family i.e. Pied Imperial Pigeon (Ducula bicolor, Scopoli 1786) and Nicobar Green Imperial Pigeon (Ducula aenea nicobarica, Pelzeln, 1865) from Great Nicobar Island of Andaman Nicobar Islands.

The sizes of 95 Torresian Imperial Pigeon colonies were estimated on 139 islands between Cooktown and Cape York, Queensland. Six colonies exceeded 10 000 pairs, 29 contained between 1000 and 10 000 pairs, 60 colonies contained fewer than 1000 pairs, and 44 islands had no breeding. Mangroves are the preferred breeding habitat and coastal low wooded islands support most of the largest colonies and breeding population. The status of the study area population is compared with those in the rest of Queensland, the Northem Territory and Western Australia. The area between Cooktown and Cape York supports the largest population and colonies of Torresian Imperial Pigeons in tropical Australia, and has large areas of undisturbed mainland rainforest feeding habitat. Current levels of protection of the species are examined. Management procedures should include: protection of the major colony islands and feeding habitat north of Cooktown; prevention of hunting and human disturbance; and a joint approach with Paupa New Guinea and Indonesia to manage this migratory species.

Basal metabolic rate (MR), body temperature (T ) and wet thermal conductance (C ) of three tropical species of bw et fruit-doves were investigated at ambient temperatures (T ) of 11 - 33 8C in activity (a) and rest (r) phases to investigate a the possible effect of obligate frugivory on the physiology of columbids. The basal metabolic rates of Ptilinopus melanospila (black-naped fruit-dove, 94 g), Drepanoptila holosericea (cloven-feathered dove, 198 g) and Ducula pinon (Pinon's imperial pigeon, 748 g) are 20 - 38% lower than predicted for all birds, including granivorous columbid species from temperate and tropical regions. The MR was minimal at a T value of approximately 30 8C (slower critical a temperature, T ) for all three species, indicating that these rainforest birds are not able to withstand high ambient lc temperatures as well as arid-adapted members of the pigeon family. Minimal wet-thermal conductance was, on average, higher than expected, indicating poor insulation in these tropical birds. Body temperatures were as expected; however, below T the body temperatures decreased to levels of 35 - 36 8C (T s12 8C). 2002 Elsevier Science Inc. All rights lc a reserved.

Torresian Imperial-Pigeons, a breeding summer migrant to northern Australia, were counted during their evening return flight to North Brook Island, 29 km off Cardwell, from 1965166 to 1985186. In the first four years numbers declined from 4692 to a low of 145 1 in the 196819 season, followed by a recovery over eight years to a December maximum of 9808. Thereafter, counts have fluctuated between about 10 000- 13 000 Imperial-Pigeons returning to the island in the evening flight, except for a sudden increase to 21 815 in January 1986. The population decline is attributed to shooting of the Imperial-Pigeons at the nesting colony, and the population recovery to subsequent protection.

Summary Newcastle disease virus could be isolated from demoiselle cranes (Anthropoides virgo), greater flamingos (Phoenicopterus ruber) and a pied imperial pigeon (Ducula bicolor) in chicken embryo fibroblast (CEF) cultures. All of these birds died without prominent symptoms and had no typical pathological lesions. Identification and characterisation studies of the viruses were performed in CEF cultures and embryos. Serological cross reactions could be detected between NDV strain B1 and the new isolates by haemagglutination inhibition and plaque reduction tests. Electron microscopic examination revealed particles with paramyxovirus morphology. Inoculation of susceptible cockerels resulted in severe clinical symptoms and mortality. The distribution of lesions in the digestive tract indicates that the isolated viruses are of the velogenic viscerotropic type.

SummaryTwo new species of coccidia, Eimeria gourai sp. nov. from the Victoria crowned pigeon (Goura victoria Fraser) and Eimeria duculai sp.nov. from the Torres Strait imperial pigeon (Ducula spilorrhoa Gray) have been described. Eimeria gourai oocysts are spherical to sub-spherical in shape, measure 20·0 (19·0–22·0) × 20·0 (18·0–21·0) μm and are devoid of micropyle and oocyst residuum. Elongate sporocysts are 12·0 × 5·5 μm, and contain a granular residuum. Eimeria duculai oocysts are broadly ovoid with an inconspicuous micropyle at the narrower end. They are 28·0 (26·0–31·0) × 25·0 (23·0–27·0) μm in size, without residuum but with a membrane-bound polar granule. The elongate sporocysts are 15·5 × 7·2 μm, with prominent Stieda body and granular, membrane-bound residuum. The morphological characteristics of the known coccidian oocysts from birds of the avian order Columbiformes are reviewed.

(1985). Torresian Imperial-Pigeon Ducula Spilorrhoa on Green Island, North-Eastern Queensland. Emu - Austral Ornithology: Vol. 85, No. 4, pp. 261-263.

A new species of extinct Ducula pigeon is described from abundant fossil material excavated from late Quaternary deposits on Henderson Island, Pitcairn Group, South Pacific Ocean. Tarsometatarsi that are longer than any extant Ducula and relatively reduced wing elements separate this species from all other extinct and extant Ducula. The description of this species adds another large endemic columbid to the suite that has become extinct since the arrival of man on one of the more isolated islands and island groups in the Pacific.