THE YELLOW- RUMPED HONEYGUIDE

 

The yellow-rumped honeyguide (Indicator xanthonotus) is a sparrow-sized bird in the honeyguide family that is found in Asia, mainly in montane forests along the Himalayas. They are very finch-like but the feet are strong and zygodactyl, with two toes facing forward and two backward. They perch on honeycombs and feed on wax. Males tend to be territorial and stay near honeycombs while females and juveniles forage widely. They are brood parasites, laying their eggs in the nests of tree-hole breeders, possibly barbets.

 From Eaglenest Wildlife Sanctuary in Arunachal Pradesh, India

Description

From Pabyuk-Naitam, East Sikkim, India.

John Gould.

The yellow-rumped honeyguide is sparrow sized and has a stout finch-like bill. The plumage is largely dusky olive and the forehead and lores are orange while the upper plumage. There is a streaked appearance to the wing feathers. The rump is deep orange and extends into the back grading to sulphur yellow. The chin and throat are yellowish while the lower plumage is pale grey with dark streaks. The bill is yellow but dark towards the tip. Females have less extensive yellow on the face and the rump is yellow and lacks the orange. Allan Octavian Hume described the subspecies radcliffi (after Colonel E. Delmé-Radcliffe^[2]) based on specimens from Hazara but no specimens or information from the region have subsequently been obtained putting it in some doubt. The species was described by Blyth based on specimens from near Darjeeling. Ripley described specimens from the Naga Hills as subspecies fulvus (not always recognized), said to be smaller and darker, with the streaking on the abdomen reduced and the yellow on the forehead restricted to the anterior.^[3] This population may be identical to the nominate of the eastern Himalayas.^[4][5] They have twelve tail feathers and nine primaries. The wing is long and pointed.^[6][7]

 

Behaviour and ecology

Head

A chipping call is produced in flight and when agitated. The flight is straight (may sometimes be undulating^[5]) and direct, sometimes in flocks of 20 to 30 birds. At deserted honeycombs, the bird clings tight and presses its tail on the surface of the comb. They feed mainly on the foundation wax of Apis laboriosa that attach the comb to rocks. They feed on active beehives without disturbing the bees much.^[4] They have been observed to make use of the attacks of Vespa mandarinia on Apis laboriosa colonies.^[8]

A display of a male involved fluffing its feathers, holding the bill high and flicking wings while swaying from side to side. A female was observed flicking its tail and pressing it down with wings drooped before being mounted by a male.^[4] They are brood parasites, laying their eggs in the nest of host species. The host species for the yellow-rumped honeyguide are as yet unknown and undocumented. Young birds of honeyguide species have bill-hooks with which they destroy the eggs and chicks of the host.^[5] The male holds territories around hives and are polygynous, allowing females with whom it had mated and their young into the territories. This mating system has been termed as "resource-based non-harem polygyny".^[9]

Unlike other honeyguides, this species has not been observed to lead humans and bears to bee hives.^[5]

 

Distribution and habitat

Adult photographed in West Sikkim, India

The species has been recorded from northern Pakistan (Hazara and Murree Hills^[10]) but the population here may have been extirpated^[5] and then in the Himalayan regions of India from western Uttar Pradesh and Himachal Pradesh extending into Nepal, Sikkim, Arunachal Pradesh and Bhutan (where it is relatively common). It is also found in southeastern Tibet and northern Myanmar.^[5] It is found in coniferous and dry-deciduous forest with rocky boulders and cliffs. May make altitudinal movements seasonally.^[6]

 

 

 

 

 

 

THE LONG- BEAKED COMMON DOLPHIN

 

 The long-beaked common dolphin (Delphinus capensis) is a species of common dolphin. It has a more restricted range than the short-beaked common dolphin (D. delphis). It has a disjointed range in coastal areas in tropical and warmer temperate oceans. The range includes parts of western and southern Africa, much of western South America, central California to central Mexico, coastal Peru, areas around Japan, Korea and Taiwan, and possibly near Oman.^[1][3] Vagrants have been recorded as far north as Vancouver Island. They live in shallow, warmer temperature waters near the coast. They also live in the tropical and subtropical regions.^[4]

 

 

Physical characteristics

 

The long-beaked common dolphin is medium-sized, but smaller than the more popular bottlenose dolphin. Adults range between 1.9 and 2.5 m (6.2 and 8.2 ft), long, and can weigh between 80 and 235 kg (176 and 518 lb), although a range between 80 and 150 kg (180 and 330 lb) is more common.^[5] Males are generally longer and heavier.^[5] The color pattern on the body is unusual. The back is dark and the belly is white, while on each side is an hourglass pattern colored light grey, yellow or gold in front and dirty grey in back.^[6] This species also has a rounded melon on tops of their heads used for echolocation.^[4] It has a long, thin rostrum with up to 60 small, sharp, interlocking teeth on each side of each jaw.^[7] They have more teeth than any other delphinids.^[8]

 

Taxonomy

Delphinus c. tropicalis in the Red Sea

The long-beaked common dolphin is a member of the common dolphin genus, Delphinus within the dolphin family, Delphinidae in the cetaceans order.^[4] Until the mid-1990s, the different forms within Delphinus were not recognized as separate species, but were all considered members of the species D. delphis.^[3][5] In 1994, Heyning and Perrin^[9] did research on these species and then Kingston and Rosel^[10] confirmed there were two separate species. Currently, the two recognized species of Delphinus  are the short-beaked common dolphin (D. delphis) and the long-beaked common dolphin.^[1] The long-beaked common dolphin is generally larger with a longer beak than the short-beaked common dolphin and has a longer rostrum.

The Indo-Pacific common dolphin is sometimes considered a separate species (D. tropicalis), but is more often considered a form of the long-beaked common dolphin.^[1][3]

Behavior

Delphinus capensis with whale watching vessels off Kochi, Japan

Long-beaked common dolphins can live in aggregations of hundreds or even thousands.^[3] Within these large groups, smaller subgroups of 10 to 30, related in either sex or age, typically are found.^[4] They sometimes associate with other dolphin species, such as pilot whales.^[3] They have also been observed bow riding on baleen whales, and they also bow ride on boats.^[3] Breaching behavior and aerial acrobatics are common with this species.^[5]

 

Diet

 

The long-beaked common dolphin has a varied diet consisting of small schooling fish, such as sardines, anchovies, mackerels, pilchards, mullet, drum or croaker. These dolphins may occasionally eat small cephalopods such as octopuses and squid, and more rarely eat small crustaceans like large shrimp or small crab. Since they gather in huge superpods and there is seldom enough food in one place to support all of them, smaller groups leave the main pod for a few hours to feed.^[11] They are able to dive in the water to about 900 feet (270 m) and hold their breath for up to 8 minutes to catch prey.^[4]

 

Reproduction

 

 

See also: Dolphin (Reproduction and sexuality)

The long-beaked common dolphin has a gestation period of 10 to 11 months typically during spring or autumn.^[4][5] The newborn calf has a length of between 80 and 100 cm (2.6 and 3.3 ft) and a weight of about 10 kilograms (22 lb).^[5] The young and juvenile dolphins coloration and patterns are darker than the adults.^[11] Typical interbirth interval ranges from one to three years.^[5] In captivity, this dolphin has hybridized with the common bottlenose dolphin (Tursiops truncatus).^[3][12] One of the hybrids has been bred back to a bottlenose dolphin, demonstrating such hybrids are fertile.^[12] The long-beaked common dolphin can live up to 40 years.^[4]

 

Relationship to humans and other species

 

Long-beaked common dolphins are not common in human care as they are extremely difficult to keep in captivity. In the wild, however, they have been seen travelling with bottlenose dolphins, pilot whales, and yellowfin tuna.^[13]

 

Conservation

 

Delphinus capensis is covered by the Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia^[14] and the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MoU).^[15] One of the main threats to the long-beaked common dolphin is fisheries. Out of 930 dolphins observed off of Peru between 1985 and 2000, 120 of them had many lacerations on their head, skin, appendages, and teeth. Most of these injuries were from fisheries-related connection.^[16] Another threat to this species is pollution because many of them have shown signs of organochlorine residue on their blubber.^[17] On the coast of California there are only about 25,000 to 43,000 dolphins and on the coast of South Africa there are 15,000 to 20,000.^[5]

 

 

 

 Binomial name

 

 Delphinus capensis

Gray, 1828

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

THE RUFOUS- BELLIED EAGLE

 

The rufous-bellied eagle or rufous-bellied hawk-eagle (Lophotriorchis kienerii) is a bird of prey in the family Accipitridae that is found in the forested regions of tropical Asia. Relatively small for eagles and contrastingly patterned like a falcon, this species was earlier placed in the genus Hieraaetus and sometimes also in the genus Aquila but thought to be distinctive enough to belong to a separate genus.

 

Taxonomy and systematics

A captive adult rufous-bellied eagle.

This eagle was originally described as Astur kienerii on the basis of a specimen from the Himalayas. It was later moved to Limnaetus by Jerdon, the genus Lophotriorchis and still later to Hieraaetus, the so-called "hawk-eagles".^[5] A study of the phylogeny of some Hieraaetus species and other eagles indicated that they were nested within the Aquila clade of eagles, resulting in their repositioning. Another molecular study of the eagles suggested that kienerii was distinctive enough to be retained in a separate genus^[4] for which the name Kienastur had been suggested^[6] but as this occurred in a thesis it is invalid for taxonomic purposes, and in any case Lophotriorchis was proposed much earlier (though originally shared with the Black-and-chestnut eagle which is nowadays placed in Spizaetus).

Within its wide range, two subspecies are recognized although there is no marked plumage difference. The nominate kienerii of India and Sri Lanka (the northern birds are larger); and formosus described by Erwin Stresemann in 1924 which is widely distributed across Southeast Asia from Burma to Sulawesi.^[7]

 

Description

 

Adult rufous-bellied eagles are distinctive in their pattern. They have a black hood with a short crest. Chestnut underparts and wing coverts contrast with the white on the throat and breast. The sexes are almost indistinguishable in plumage but females are slightly larger and have more black on the face. They perch in a very upright stance and the wingtip almost reaches the tail. The tarsus is fully feathered. Juveniles have very white underparts with dark markings on the sides of the body, head mask and edge of underwing coverts. They can appear similar to a booted eagle (Aquila pennata). In flight, the underwing lining is dark and the greater coverts are black. The flight feathers are thinly barred with a black edge. The tail is dark and barred.^[8][9]

 

 

 

The rufous-bellied eagle is found in southern and south-eastern Asia and its range also extends to Sulawesi.

This species is associated mainly with hill forests. In India, they are commoner in the Western Ghats than along the Himalayas where they occur from Nepal to Assam. They also occur in parts of the Eastern Ghats.^[10][11]

 

Behaviour and ecology

 

 

  Rufous-bellied eagles are usually seen in flight, soaring high over the forest canopy. They dive to capture prey that can include birds and mammals in the air, canopy, or forest floor. Birds the size of the Sri Lanka wood pigeon, Kalij pheasant and junglefowl have been recorded as prey.^[12][13] The breeding season of the eagles is in winter with the young fledging in spring when the prey species are also breeding. The display flight involves stooping and wing-quivering. Their calls include a series of high pitched fwick, fwick... notes followed by a thin sweek!. They nest on a large, often bare tree,^[14] building a large platform of dry sticks and branches that they break off.^[8][15][16] The nest is lined with green leaves and a single egg is laid. Both parents take turns in incubation, feeding and nest defence.^[9]