Field of Science

The Rosy Birds

Violet-necked lories Eos squamata, copyright Niels Poul Dreyer.


In taxonomic days of yore, it was a not uncommon practice for new genera to be baptised under the names of classical figures: gods, heroes, emperors, even the occasional prophet (the practice only died down once the barrel of available names became largely empty). In many cases, the connection drawn between the organism in question and its awarded namesake was tenuous at best. In others, it was simply non-existent. But in a favoured few cases, the association fit perfectly.

Eos is a small genus (recent authors have recognised six species) of lories found on islands in eastern Indonesia. They are named, of course, after the Ἠώς ῥοδοδάκτυλος, the 'rosy-fingered dawn', of the ancient Greeks. It takes no great insight to realise why they were so-called: all members of the genus are predominantly coloured in a vibrant red, together with varying extents of blue, purple and/or black. Green is usually absent from their plumage (with some noteworthy exceptions that I'll have cause to mention again), distinguishing them from most closely related parrots such as the rainbow lorikeets in the genus Trichoglossus. Charles Lucien Bonaparte (nephew to the other Bonaparte, and a prominent nineteenth-century ornithologist) stated in 1850 that Eos could be recognised by its "elegant form, small stature, compact, red plumage with more or less blue; compressed, moderate, red bill, with the cere apparent... and longish, not very broad, wedged tail".

Blue-streaked lories Eos reticulata, copyright Doug Janson.


For the most part, Eos species are found on islands between Sulawesi and New Guinea. The black-winged lory Eos cyanogenia is found on islands in Geelvink Bay, in the north-west part of West Papua, but not on the mainland of New Guinea itself. For the most part, no island is home to more than one species of Eos. The island of Seram is an exception, with the endemic blue-eared lory Eos semilarvata found in the central highlands, and the red lory Eos whatchumacallit (see below) closer to the coast (this species is also found on other islands in the South Moluccas). The blue-streaked lory Eos reticulata is found in the Tanimbar group east of Timor. The violet-necked lory Eos squamata lays claim to the North Moluccas, and the red-and-blue lory Eos histrio is found on Talaud and other islands to the north-west of Sulawesi (Juniper & Parr 1998).

Black-winged lory Eos cyanogenia, copyright Lip Kee Yap.


While the taxonomy of the group has been mostly stable in recent years, it was not always so. Bonaparte (1850) snidely commented that some species of Eos had been described "too many times". Hume & Walters (2012) referred to five described species of Eos, all based on isolated specimens since lost, whose identity has been contested. While it is possible that some may represent species now extinct, it is equally possible that they represented unusual individuals of living species. In the absence of examinable type specimens, the identity of most is of academic interest only. The exception is the 'red-and-green lory' Eos bornea, which was originally named Psittacus borneus by old Carolus Linnaeus himself on the basis of a description and plate of a lory supposedly from Borneo published in 1751 by George Edwards (Walters 1998). Edwards' bird, which he had bought as a stuffed specimen from a toyshop in London, was described as dark pink, with a yellow bill, and green patches on the wings and tail. However, no species quite matching Edwards' description is known from Borneo or anywhere else, and it was subsequently suggested that he may had an unusual or a faded specimen of the Moluccan red lory, with the Bornean locality being an error. As such, the name Eos bornea came into use for the red lory, replacing the later-published name 'Eos rubra'. However, Walters (1998) subsequently disputed this identification, recommending the continued use of E. rubra. At present, 'Eos bornea' still seems to be the more commonly used name, and my own sympathies would be more with maintaining the familiar usage than with insisting on strict adherence to the original concept.

Red lories, Eos... let's just say bornea, shall we? Copyright Arnaud Delberghe.


Because of their striking appearance, Eos species have been heavily collected for the pet trade. The have also been widely affected by habitat degradation with the clearing of primary forests. While populations of most species are still regarded as reasonably robust, the IUCN regards all except E. squamata as on the decline. Eos histrio is regarded as actively endangered, having all but disappeared from some of its home islands. In 1999, it was estimated that 1000 to 2000 red-and-blue lories were being captured and exported for the pet trade each year—despite the total population of this species probably being not much more than 20,000 individuals!

REFERENCES

Bonaparte, C. L. 1850. On the trichoglossine genus of parrots, Eos, with the description of two new species. Proceedings of the Zoological Society of London 18 (1): 26-29.

Hume, J. P., & M. Walters. 2012. Extinct Birds. T. & A. D. Poyser.

Juniper, T., & M. Parr. 1998. Parrots: A guide to the parrots of the world. Christopher Helm Publishers.

Walters, M. 1998. What is Psittacus borneus Linnaeus? Forktail 13: 124-125.

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