REGUA bird checklist updated

Just finished the third edition of the Checklist of the Birds of REGUA. This edition updates the taxonomy and nomenclature introduced by Brazilian Committee of Ornithological Records (CBRO) in January 2014, based on the classification the South American Classification Committee (SACC) - an official committee of the American Ornithologists' Union (AOU).

The Checklist of the Birds of REGUA is, to the best of my knowledge, still the only checklist of birds in Latin America to include
seasonal abundance charts.

A continuously improving understanding of evolutionary relationships from phylogenetic studies has resulted in many changes to the list. The biggest sequence change is the separation of the Falconiformes (caracaras and falcons) from the Accipitriformes, with the former now placed between the Cariamiformes (seriemas) and Psittaciformes (parrots). Also adopted is the AOU's reorganisation of Wood-warbler taxonomy. The genera Dendroica, Parula and Phaeothlypis are no more - Tropical Parula Setophaga pitiayumi and Blackpoll Warbler Setophaga striata are now both placed in the genus Setophaga, and Neotropical River Warbler Myiothlypis rivularis moves into Myiothlypis, along with White-browed Warbler Myiothlypis leucoblephara.

Falconiformes such as Southern Caracara Caracara plancus have been separated from the Accipitriformes

Two species on the REGUA list have been split: American Barn Owl Tyto furcata is split from Barn Owl Tyto alba, and the South American brown-eyed form of Red-eyed Vireo Vireo olivaceus is now considered to be a separately species - Chivi Vireo Vireo chivi.

Since the second edition of the checklist was published in May 2012, five more bird species have been found at REGUA: Black-collared Hawk Busarellus nigricollis, Rufous Nightjar Antrostomus rufus, American Pygmy Kingfisher Chloroceryle aenea, Brown-crested Flycatcher Myiarchus tyrannulus and Grassland Yellow-Finch Sicalis luteola; bringing the total number of birds recorded here to an incredible 464, including 118 Atlantic Forest endemics and 62 Brazilian endemics!

Brown-crested Flycatcher Myiarchus tyrannulus, REGUA, 18 September 2012 - the first record for the reserve. Preferring open or
semi-open habitats such as cerrado and savanna, this was a somewhat unexpected find at REGUA, especially now that the
reforested areas are maturing.

The checklist is written in both English and Portuguese and will be available to buy at REGUA as well as in the UK in the next few weeks. If you would like a copy please email me at webmaster@regua.co.uk. Copies cost £3 plus £1.60 postage and all funds go directly towards our conservation work in Brazil's highly threatened Atlantic Forest.

The notorious tapaculo

In 2007, Mouse-coloured Tapaculo S. speluncae, a species found in the mountains of the Atlantic Forest in South America, was split by the Brazilian Committee of Ornithological Records (CBRO) and renamed Serra do Mar Tapaculo Scytalopus notorius (after the Serra do Mar mountains of the region). Birders everywhere (okay, birders in Brazil) were just starting to get used to the new name when the CBRO suddenly, and mysteriously, reversed their decision!

The Scytalopus genus of tapaculos are arguably the most taxonomically complex passerines in Latin America. Typical tapaculos, they are extremely difficult to see which makes them very tricky to study. In fact, they appear to like nothing more than remaining hidden from frustrated birders by creeping around mouse-like in dense vegetation, while monotonously calling their heads off! But over the last few decades new populations have been discovered and the genus has seen enormous taxonomic changes, with around 40 species now recognised compared to just 11 in 1970³. Associated with mountains, most are found in the Andes but some are restricted to south-east South America where six species are now recognised, three of which have been described since 2005!

The specific name of Mouse-coloured Tapaculo - speluncae - has long been the subject of intense taxonomic debate, with ornithologists divided over whether this is the same species originally described and given this name. The answer not only has significant implications for the nomenclature of Mouse-coloured Tapaculo, but also for other Scytalopus species recently discovered in south-east Brazil.

What's in a name? The nomenclature of Mouse-coloured Tapaculo Scytalopus
speluncae has long been a topic of intense debate, with ornithologists divided over
whether this is the same species described and attributed the specific name
speluncae by Édouard Ménétriés in 1835. This male at Pico da Caledônia, Rio de
Janeiro state, Brazil, in October 2007, was laughing so uncontrollably at our efforts
to work it out, that it momentarily forgot that it was supposed to be skulking around
in dense vegetation annoying birders and allowed itself to be photographed out in
the open for a change.

In 1835, French zoologist, Édouard Ménétriés, collected and described the first Scytalopus tapaculo in the region - an adult male collected in the Espinhaço mountains in Minas Gerias state, near the town of São João del Rei, that he named Malacorhynchus speluncae (placed in the genus Scytalopus today). Ménétriés described it as uniform mouse grey above, slightly paler grey below and becoming whitish towards the middle of the breast and on the throat (illustration of type specimen below). Subsequently, similar, albeit darker birds were discovered in the Atlantic Forest mountains in Rio de Janeiro state, a long way from the Espinhaço mountains, and identified by ornithologists Hellmayr (1907) and Ihering & Ihering (1907) as belonging to the same species (know today as Mouse-coloured Tapaculo).

Surprisingly, no other Scytalopus tapaculos were subsequently found in the São João del Rei region and so ornithologists questioned São João del Rei as the type locality of Ménétriés specimen³ (a notion given credence after the type localities of other specimens collected by Ménétriés were found to be erroneous), suggesting it was actually collected in the Atlantic Forest.

Illustration of the S. speluncae type specimen described by
Ménétriés in 1835. Note the whitish throat, grey flanks with no
buff and pale legs. (Édouard Ménétriés)

Then in the 1990s, not one but two forms of Scytalopus tapaculo were discovered hiding out in the Espinhaço mountains - one in the northern part of the range (described in 2005 as Diamantina Tapaculo S. diamantinensis), and the other in the south around São João del Rei! However, these São João del Rei birds are quite different, morphologically and vocally, to the Atlantic Forest taxon, being paler grey, noticeably whitish on the central belly and most significantly, buff with dark barring on the flanks, rump and under tail coverts (photo here)³. They were clearly a different species, and so which species had Ménétriés described? Was it the São João del Rei species afterall, or a bird from the Atlantic Forest as suggested? Whichever one it is must be attributed the name speluncae, and the other would need to be described as a new species.

Scytalopus tapaculo species discovered at São João del Rei,
the type locality of S. speluncae described by Ménétriés.
Note the obvious buff barred flanks and rump, medium grey
underparts and pale legs. (Vitor Torga Lombardi)

A study by Raposo et al. published in 2006, re-examined Ménétriés's type specimen and compared it with new topotypes collected from São João del Rei, as well as specimens from the Atlantic Forest. Although the specimen is damaged, they found a few buff feathers on the rump and flanks of the type specimen (not mentioned by Ménétriés) and argue that these, together with the whitish central belly and throat and paler mid-grey colouration, are all features not found on the Atlantic Forest birds³ (especially adult males¹). Therefore, Ménétriés's type specimen must be from São João del Rei, and so the name speluncae must be applied to this form and Mouse-coloured Tapaculo must be described as a new species, for which they proposed the name Serra do Mar Tapaculo Scytalopus notorius (notorius because of the controversy surrounding the species).

The following year, this proposal was adopted by the CBRO and the issue seemed to be settled, but then three years later a similar study by Maurício et al.¹ concluded completely the opposite! They point out that the plumage of adult male Mouse-coloured Tapaculo actually varies considerably - ranging from homogeneous blackish grey with no traces of any buff feathers (as put foward by Raposo et al.), to mid-grey with some buff barred feathers on the flanks and rump (a feature shown by about 25% of adult males). In contrast, the São João del Rei taxon exhibits a very clearly marked plumage pattern (see above), being dark grey above and paler grey below a whitish center to the belly and obvious buff barred flanks, vent, under tail coverts and rump. They showed that the buff feathers on Ménétriés type specimen are nowhere near extensive enough for it to be the São João del Rei species, and also the central belly on the type is actually medium grey and not white. However, the plumage of Ménétriés type falls well within the variation found within Mouse-coloured Tapaculo, and therefore the Atlantic Forest species must retain the name speluncae.

In the end, Maurício et al. won the support of the South American Classification Committee and the CBRO reinstated Mouse-coloured Tapaculo as the name of the Atlantic Forest species. With this issue finally laid to rest, the São João del Rei species could be formally described, and in 2010 was announced as a new species - Rock Tapaculo S. petrophilus.⁴

Adult male Mouse-coloured Tapaculo Scytalopus speluncae, Pico da Caledônia,
Rio de Janeiro state, Brazil, October 2007. Same bird looking less smug now that
ornithologists have finally worked out what it is! Endemic to the mountains of the
Atlantic Forest, this is the darkest and most uniform in plumage of it's genus in
south-east Brazil, but they are variable, with the male sometimes showing some
buff on the flanks or rump. Note the dark grey plumage, very slightly paler throat,
lack of white on the underparts and dark legs and bill.

References

¹ Maurício, G.N., Bornschein, M.R., Vasconcelos, M.F., Whitney, J.F., Pacheco, J.F. & Silveira, L.F. (2010) Taxonomy of "Mouse-colored Tapaculos". I. On the application of the name Malacorhynchus speluncae Ménétriés, 1835 (Aves: Passeriformes: Rhinocryptidae). Zootaxa 2518: 32–48.
² Raposo, M.A. & Kirwan, G.M. (2008) The Brazilian species complex Scytalopus speluncae: how many times can a holotype be overlooked? Revista Brasileira de Ornitologia 16(1): 78–81.
³ Raposo, M.A., Stopiglia, R., Loskot, V. & Kirwan, G.M. (2006) The correct use of the name Scytalopus speluncae (Ménétriés, 1835), and the description of a new species of Brazilian tapaculo (Aves: Passeriformes: Rhinocryptidae). Zootaxa 1271: 37–56.
⁴ Whitney, B.M., Marcelo, F.V., Silveira, L.F. & Pacheco, J.F. (2010) Scytalopus petrophilus (Rock Tapaculo): a new species from Minas Gerias, Brazil. Revista Brasileira de Ornitologia 18(2): 73-88.

Brazilian moorhens - a laughing matter

When I first visited Brazil over five years ago, I soon became aware of how different the long 'cackling' calls of the local race of Common Moorhen Gallinula chloropus galeata are compared to the familiar short calls of nominate G. c. chloropus back in the UK. A closer look at these birds also revealed that they look a little different too, being slightly bigger with a larger red shield with a broad square top edge, giving the head profile a peak at the front of the crown. With the recent taxonomic scrutiny of moorhens focusing on the variation between Old World and New World forms, much has been written about the morphological differences between the North American race G. c. cachinnans and Old World chloropus, that might allow a transatlantic vagrant to be identified. Adult cachinnans, in addition to the features above, tend to show a different bill pattern with less extensive yellow on the lower mandible and a more clearly defined red/yellow border, a duller red iris and richer reddish-brown upperparts, particularly on the upper mantle where there is a more clearly demarcated contrast with the dark grey neck (see here and here). Immature birds are much more similar and possibly indistinguishable in the field?

In July, the AOU (but so far not the BOU) decided to split all New World forms from Old World chloropus as Common Gallinule (in favour of the name Laughing Moorhen suggested by The Sound Approach). However, it is galeata, the most widespread form across South America, that has been designated the nominate race rather than cachinnans. I'd like to know what features distinguish these two races? As far as I can tell they are vocally inseparable (compare the calls of galeata and cachinnans here and chloropus here), but I've observed that galeata does appear to be much greyer on the upperparts than both Old World chloropus and North American cachinnans, with brown tones restricted to the lower mantle, rump, greater coverts and flight feathers (compare below), and perhaps they are also a little darker overall. Are there other differences?

Former race G. c. galeata, now split by the AOU as Common Gallinule Gallinula
galeata, REGUA, Brazil, November 2011. Note the large, square-topped shield, the
well defined lower mandible pattern and the dark eye. galeata seem to have much
greyer upperparts than both North American cachinnans and Old World chloropus.

Common Moorhen Gallinula chloropus, London Wetland Centre, UK, December
2011. Note the smaller, narrower shield with a rounded top, slightly more extensive
yellow on the lower mandible with a slightly less demarcated pattern, brighter red
iris and browner upperparts (click to enlarge). North American cachinnans is
apparently even browner above.

At REGUA, galeata also exhibit some differences in behaviour compared to the Old World Common Moorhen. Here the birds seem to be more social, forming large flocks throughout the year, often containing 40 or so individuals that feed and rest together. They also appear to be more aquatic in their feeding habits, preferring to forage in open and often quite deep water, picking plant material from the surface, and feed much less frequently on land than Common Moorhen do in the UK, where bird seem to prefer to graze on grass. Has anyone noticed a similar feeding behaviour in cachinnans, or in any other race? For some excellent footage by Ron Jackson showing the behaviour, calls and features of galeata at REGUA, click here.

A typical feeding group of Common Gallinule Gallinula galeata, REGUA, July
2011. Based on observations at REGUA, Brazilian birds are seemingly much
less terrestrial in their feeding habits than their Old World counterparts?

Common Moorhen Gallinula chloropus London Wetland Centre, UK, December
2011. Birds in the UK seem to prefer grazing on land.

So is the situation as straightforward as separating New World from Old World moorhens? Looking at photos, meridionalis from sub-Saharan Africa and St. Helena in the mid South Atlantic (here), orientalis of south-east Asia (here), and pyrrhorrhoa from Madagascar and surrounding islands (here), all look very similar to galeata to me, with perhaps a very slightly more rounded top to the shield. Have these been allied to Common Moorhen or Common Gallinule, and are they also different species?