COTINGA 10 Notes on the rediscovery of the Austral antarcticus in Santa Cruz, Argentina

Juan Mazar Barnett, Marco della Seta, Santiago lmberti and German Pugnali

La Gallineta Chica o Piden Chico Rallus antarcticus es uno de los ralidos neotropicales menos conocidos. Con 19 registros esparcidos en Chile y Argentina, solo cinco fueron efectuados desde 7 1900, dos de los cuales son dudosos • El ultimo registro corresponde a un individuo hallado muerto en las cercanias de El Balson, Rio Negro, Argentina en 195920 • Presentamos aqui los detalles del descubrimiento de una pequeiia poblacion de esta especie en la Estancia La Angostura (48°37'S 70°39'W), a c.570 m, en la provincia de Santa Cruz, el 12 y 13 de enero de 1998. Las aves fueron encontradas en los densos juncales de Schoenoplectus (Scirpus) californicus que formaban parches de diversos tamafios en el mallin humedo que cubria el ancho valle del rio Chico. Se describen las vocalizaciones que fueron grabadas por primera vez, comparandolas con las de Rallus limicola a las que se parecen. Se hace una resefia y discusion de los registros existentes ademas del aparente patron migratorio que estos sugieren, y la posible preferencia por habitats de bosque 0 de estepa. Nuestros registros hasta ahora no permiten cerrar las interrogantes que siguen ab.ier-tas acerca de la biologia de esta especie. Esta previsto un programa de relevamientos a traves de un Premio de Conservacion del CAN, que esperemos permitan dilucidar estos y otros aspectos de la situacion de Rallus antarcticus.

Introduction sented by Hardy et al. 14 to try and obtain a response Austral Rail Rallus antarcticus, is one of the least from Austral Rail, but without success (see below). known rallids in the Neotropics. It has been classi­ On arriving at Estancia La Angostura in the fied as Endangered/Extinct (possibly extinct)7, the evening (c.21h00) of 12 January, we decided to try same category as such as Eskimo Curlew playback once more in the rushbeds of the rio Chico Numenius borealis or Glaucous Macaw valley, but before we could do this, a with a Anodorhynchus glaucus. It is known from only 19 similar song to Rallus limicola called from the localities throughout Patagonian Argentina and reeds. It was undoubtedly an Austral Rail (see Chile, with a few records in central Argentina and Vocalisations). 7 central Chile • There are only five 20th century re­ Soon four different were calling from a ports, two of which are considered doubtful or marshy area of 300 x 200 m. One individual was 7 uncertain • It was last reported on 29 October 1959 observed through making extensive tape-recordings when one. was found dead in a wet grassy field by a of its song and then attracting it to playback. It stream near El Balson, Rio Negro (48°35'S was relatively tame, but always kept within the 71°3l'W); this specimen is now housed at Museo dense rush cover, c.50 cm from the edge of the veg­ Argentina de Ciencias Naturales20 (C. Kovacs pers. etation. It walked over a dense mattress of dead comm.). rushes, c.40-50 cm above the water level. When it Here, we report the discovery of a small popu­ reached the edge of a patch of rushes 75 cm from lation at Estancia LaAngostura (48°37'S 70°39'W), the next such patch, the bird submerged until only at c.370 m, and provide the first detailed descrip­ the head and part of the back were above the wa­ tions of the habits and habitat of the species, as ter surface, and swam this distance, covered by well as a description of its vocalisations which were the aquatic grass and milfoil. All the distinctive previously unknown. characters of the species were noted: in addition to its small size-c.20 cm-the bird had brown­ Observations washed huffy upperparts, coarsely streaked We found Rallus antarcticus on 12-13 January blackish; dark plumbeous underparts; black belly 1998 in rushbeds bordering the rio Chico, Santa and vent, finely barred white. The mandible and Cruz province, Argentina. The fact that Rallus cutting-edge of the maxilla were dull meat-red and antarcticus has been considered a subspecies of the rest of the bill dull dusky. Legs were dull pinky Virginia Rail R. limicola led us to believe that its red. The iris was not seen well but appeared dull voice would probably resemble limicola, and we red. No rufous patch was apparent on the wing­ thus used examples of the latter species' voice pre- coverts, as these were concealed by the scapulars

96 COTINGA 10 Rediscovery of the Austral Rail Santa Cruz, Argentina and other feathers. The following morning we rived at Estancia LaAngostura at c.2lh00, 75 min­ heard at least three birds calling in the same area, utes before dusk. At this time, four individuals from 06h00-08h00. Some tape-recordings were were calling sporadically (every c.2-3 minutes). made from a distance. Notably, when J . Fjeldsa However, as the sun set, the bird which was at­ and N. Krabbe visited Ea. LaAngostura on 12 Feb­ tracted to playback sang more frequently and ruary 1984, they heard a rail-like song from the continued until it was dark (c.22h00), by which same marshy area as that in which our observa­ time it was singing every 8--51 seconds, but most tions were made. This could conceivably have been intervals were either 14-17 seconds or 31-39 sec­ Rallus antareticus (J. Fjeldsa in litt. 1998). onds long. The next day we first heard the species On the 12 January, during the journey from El at c.06h00, c.30-50 minutes after dawn, when it Calafate to LaAngostura along Route 40, we twice sang at 1-2 minute intervals. stopped in areas which appeared suitable for Aus­ Song length varied, from 5-10 notes, but the tral Rail and tried to lure a response through vast majority had 7-9 notes. Notes were either a playback of the calls and songs of Rallus limieola. single-syllable pie or two-syllable pi-rie, but were These attempts, by a small stream at the side of a always high-pitched and strident with a very slight plateau with limited wet grass and small stands rasping or metallic quality. The two-syllable notes of rushes, failed. Further efforts, this time using may alternatively be transcribed as pi-den. Nota­ the voice of Rallus antaretieus, were made on 15 bly, piden is the name given to the species in Chile, January 1998 near El Pluma, where Route 43 and it seems plausible that this name is onomato­ crosses the stream of the same name, a small tribu­ poeic. Songs may be transcribed as a series of pie tary of the rfo Deseado (46°29'S 70°13'W). Again, pi-rie pi-ric pi-ric pi-rie pi-rie pi-ric with one or this was unsuccessful. more pi-rie notes occasionally replaced by pie notes, Other negative results include a search by R. and sometimes lacking the introductory pie. Fraga of five areas of apparently suitable habitat Compared to the song of Virginia Rail as pub­ 14 in Los Alerces National Park, on 6-11 February lished by Hardy et al. , Austral's song is less 1998. Specific searches were conducted using our rasping and higher pitched. Virginia Rail delivers tape of Austral Rail, in marshy areas within Cipres 5-8 note songs every 3-4 seconds (examples one 14 Austroeedrus chilensis, MaitenMaitenus boaria and and two of Hardy et al. ). These differences are Nire Nothofagus antaretiea southern beech forests. noticeable compared to the songs of several of No Rallus antaretieus were recorded; Pardirallus Laterallus crakes, which can be very similar (JMB sanguinolentus was found on one occasion. pers. ohs.). The only available recording of the third taxon belonging to the superspecies-the Bogota Habitat Rail Rallus semiplumbeus14-is of a completely dif­ The birds were found in extensive marsh habitat ferent song type. bordering the rfo Chico. This river valley, which dis­ The calls of Speckled Teal Anas flavirostris can sects the Cardiel plateau, was knee-deep in water also resemble single Austral Rail notes, although in January 1998. The marsh consisted of an open the duck's are softer, more flute-like, and less stri­ area densely covered by milfoil Myriophyllum sp. dent. and lush green grass, with large patches of dense, tall (c.2 m) rushes Sehoenopleetus (Seirpus) Range ealifornieus of various sizes. The rushes were al­ Austral Rail is largely restricted to Patagonia. In most impenetrable, and a significant proportion Argentina, it has been recorded in Buenos Aires were dry and bent over, forming a natural platform province during the autumn or winter, except for a 7 above the water surface. Other species present in­ doubtful breeding record • The records in Buenos cluded Wren-like Rushbird Phleoeryptes melanops, Aires province appear to suggest a pattern of north­ Many-coloured Rush-tyrant Taehuris rubrigastra erly dispersion (see discussion below). All other and Yellow-winged Blackbird Agelaius thilius, as Argentine records are from Patagonia, during well as numerous waterfowl in the open areas cov­ spring and summer7• ered by milfoil. These marshes represent a natural In Chile, it has been recorded in Magallanes, oasis within the surrounding dry Patagonian steppe. southern Patagonia, in summer and autumn7 and in five localities in central Chile, in addition to sev­ Vocalisations eral skins or records for which there are no data The song of Rallus antaretieus was similar to that other than "central Chile", "Santiago" or simply 7 16 21 of R. limieola. The species was first located by its "Chile" • • • Of these five, one (a nest with six eggs distinctive voice and was calling when we first ar- found in Nov!Jmber 1940 at San Ignacio, Santiago7)

97 COT/NGA 10 Rediscovery of the Austral Rail Santa Cruz, Argentina

gust census (one in Argentinar. No locality was provided, and the species was not even mentioned under the "Comentarios sabre especies" section, which includes-amon g others- "species that stand out because of their rarity". D. Blanco (pers. co mm .) provided d etail s of the Argentine records, all of which were made by M. Di ez Tra badelo near Carhue-the same loca li ty where it was recorded by Barrows'. Trabaclelo's records were as follow s: three on 2 April 1993 and seven on 5 February 1994 at Bai1ados de Carhue (37°12'S 62°46'W); and one on 13 July 1994 at Laguna Epec uen Sur (37°12'S 62°46'W). These records require formal co nfirma­ Rushbeds at Estancia La Angostura (Juan Mazar Barnett) tion. is of uncertain identity and two others are unspec i­ No other interesting rail ob servations were fi ed as to date and lac k d etail s'. The remaining made during the J anuary- February and July-Au­ two also lack details, but are at least more co n­ gust 1992, or February 1993 and July-August 1993 sistent with other observations of the spec ies: censuses, except t hree Reil/us sp. in Argentina in Reed"" claim ed the species was found at Hacienda February 1993"· '. (Estancia) Cauquenes, Colchagua, where "it hides There have also been unco nfirmed r eports in among the g rass by the swamps" . This record is the El Bol s6 n area, Rio Negro in recent years"". undated, but presumably relates to 1875; and These refer to sightings made by C. Kov acs of birds Johnso n" publishecl an extract from a letter by Dr which m ay have been Austral Rail s, but eluded Wolffhi.igel who claimed the species was resident precise id entification. Songs of unidentified birds at Cayutue, where it could be seen "in the second were also heard in the marshes in that area (C. growth trees bordering the virgi n forest" and was Kovacs pers. co mm.). confined to the reeclb eds of lake Cayutue during Although all these records merit further inves­ summer. He also mentioned that others had told tigation, we prefer to regard them as unconfirmed, him the species was present in reeclb ecls at Peull a given the lac k of evidence or further details. and Puntiaguclo. All three locali ties are a dj acent to lake Todos los Santos, Ll anquihue. H abi tat in Discussion and conclusions this area is now all farmland and disturbed patchy Perhaps the most remarkable fact concerning our forest (M. Marin in lilt. 1998) . rediscovery is that a small population appears to Other than the historical records cited by inhabit suitable habitat at Estancia LaAngostura. Navas20 and Collar et al.7 , there have been a series Most accounts concerning the species describe of undocumented reports published in the casual encounters in which a single bird was col­ 20 2 Neotropical Wat erbird Censuses. The first such ce n­ lected '"· ·"·1. ;, or the discovery of nests of uncertain sus-in July 1990-reportecl two Austral Rails in identity'-'". In fact, these accounts provide virtu­ Chile at "Lenqui/Astilleros cerca de Maollin en Ja ally no in fo rmation on the species' habitat or habits, Region X"6 . No indication of observer, habitat or and mos t usually mention little more than the fact other details are given. Both localities are within that a s pecimen was secured, often without even secondary and di sturbed Notho(agus forests (M. mentioning a precise locality or el ate. Marin in lilt. 1998). Bl anco & Canevari" mention Extreme elates of records from Patagonia are four Austral Rails from Chile in a tabl e depi cting 29 October a nd 13 ApriF. Records in Buenos Aires the total resul ts for the July 1991 census. Under province suggest that Rallus antarcticus was for­ the "Comentarios sabre Especies" section for Chil e, merly a non-breeding v is itor to the area. it is stated that "According to Dr Schlatter, some of Barrows'-not Withington27 as erroneously sug­ the questionable records include the sighting of 4 gested by Collar et a.l.7- found the species relatively Rallus antarcticus (R. sangu.inolentu.s?) and 4 com mon at Carhue in April 1881. Withington27 re­ Numenius borealis (N. phaeopus?) , in Chiloe Insu­ corded it onl y once at Lomas de Za mo ra, where one lar (Sector Cucao)." No further details are provided was ki ll ed by clo gs in a swamp in June 1884. for either species and none of these records was Gibson''i found two separate birds on 24 July 1899 documented (R. Schlatter in lilt. 1998). In 1994, on Isla Go nzalez, Cape San Antonio, in a flood ed Austral Rail was recorded again on the February "espartillar" [Spartina densi(lora] where one of the census (seven in Argentina) and on the July-Au- birds, "unable to adopt its usual tactics of skulking

98 COT/NGA 10 Rediscovery of the Austral Rail Santa Cruz, Argentina away amongst the covert" was "disabled by a lucky effect this could have had on the Austral Rail is whip-cut.". Weller26 did not find the species during undetermined. Fjeldsa9 records that overgrazing two periods spent studying Black-headed Ducks steppe also has a significant effect on nearby Heteronetta atricapilla in Cape San Antonio, and wetlands, as bare soil is windblown and deposited Narosky & Di Giacomo 19 mention no further in pools and marshes. records from Buenos Aires. The record of two nests It is also unclear if Rallus antarcticus is a habi­ found on 1November1900 at Barracas al Sud (cur­ tat specialist, in part due to the almost complete rently Avellaneda) 15 appears doubtful and has lack of habitat data from historical records. We already been questioned by Hellmayr & Conover17 found it in a wetland within the Patagonian steppe. due to the lack of specimen material. The "possi­ Most records in the south of its range are from 7 ble" record at Concepcion del Uruguay, Entre Rios , steppe areas, whereas those from central Chile and seems more likely to refer to young Plumbeous the El Bols6n record in Argentina appear to come 1 Rails Pardirallus sanguinolentus • from southern beech Nothofagus forests. In Argen­ As mentioned above, the historical data are gen­ tina this habitat has been well documented erally poor and inconsistent, whilst the paucity of ornithologically (e.g. around Bariloche and El records, particularly from the 20th century, does Bols6n, Rio Negro, and in Los Alerces National not permit an unequivocal interpretation of the Park, Chubut, and Los Glaciares National Park, species' distribution and movements. It is possible Santa Cruz) (see Observations), and the species' that the species was formerly more widespread and absence, or near-absence, from these areas (only abundant, and that at least some individuals moved one record in El Bols6n despite Kovacs spending a north to winter in Buenos Aires province. However, lifetime collecting in this area, but see Range) there have been no records in Buenos Aires since strongly suggests that (at least in Argentina) it is 7 19 1899 · (but see Range), and it is unclear if these absent from rushy swamps in forested areas of records represented regular migration or if they Patagonia (which are usually inhabited by were just stragglers from a formerly more wide­ Pardirallus sanguinolentus). Hopefully, future sur­ spread population. If truly migratory, it appears veys will help to answer some of these questions. unusual that the species has not been recorded Rallus antarcticus is currently classified as 8 2 outside Patagonia this century. Critical " • We suspect that, given knowledge of its According to Dr Wolffhiigel 18 the species breeds voice, it will be found to be commoner than previ­ in reedbeds during the summer and spent the win· ously thought, and we expect to find it at a number ter in second growth adjacent to the lake. However, of additional localities. We plan to undertake sur­ a nest (of uncertain identity) was found under a veys throughout Santa Cruz province in order to bramble Rub us bordering an irrigation canaF. That determine its movements and assess its habitat we found the birds in dense reeds in mid-January requirements and distribution. Interestingly, our clearly suggests it breeds in such areas. record is not the first for the rio Chico. One was The reasons for the species' apparent range re­ collected by J.B. Hatcher at the "Lower Rio Chico, 24 traction and decline in numbers are enigmatic. The Patagonia" on 30 March 1897 • This locality is in scarcity of records suggests that "it was already south-east Santa Cruz22 (and refers to the same genuinely rare at the turn of the century"7• It has rio Chico) and not in south-west Rio Negro as pre­ been suggested that overgrazing and haymaking viously suggested10 (J. Fjeldsa in litt. 1998). had obviously detrimental effects for birds on river Satellite photographs reveal the presence of plains, as large quantities of aquatic vegetation reedbeds along the rio Chico downstream of La (Scirpus, Elodea, Myriophyllum etc.) are harvested Angostura, connecting the La Angostura reed beds for cattle. This could have been a significant factor those even further downstream. These areas, as 9 11 in the Austral Rail's decline · and appears at least well as others that have been identified (e.g. the partially true in some areas of Santa Cruz (SI pers. extensive marshes of rio Deseado at its junction ohs.). However, the rushy meadows of Estancia La with arroyo El Pluma), will be surveyed for Rallus Angostura have long held sheep and cattle in small antarcticus. numbers without apparently damaging the reedbed significantly, perhaps because the were Acknowledgements unable to cross a channel of deeper water. Indeed, Mario Kusanovic, owner of Estancia La Angostura, the reedbeds have increased in area during recent is thanked for his hospitality. Daniel Blanco greatly years due to particularly wet conditions (M. improved this report by providing access to spe­ Kusanovic pers. comm.). The extent to which rushy cific information from the Argentine census files of habitats were reduced through overgrazing and the Wetlands for the Americas, and Roberto Schlatter

99 COTINGA 10 Rediscovery of the Austral Rail Santa Cruz, Argentina provided details of the Chilean records. Dr Jorge 11. Fjeldsa, J. & Krabbe, N. (1990) Birds of the high Navas and Dr Rosendo Fraga allowed access to cer­ Andes. Copenhagen: Zoological Museum, Uni­ tain references, and the latter kindly allowed us to versity of Copenhagen & Svendborg: Apollo use his data. Marcos Babarskas also assisted with Books. some of the references. Carlos Kovacs provided in­ 12. Garcia Fernandez, J. J., Ojeda, R.A., Fraga, R. formation concerning the species in El Bols6n and M., Diaz, G. B. and Baiglin, R. J . (1997) Libro Jon Fjeldsa provided other useful data. Rosendo rojo de mamiferos y aves amenazados de la Fraga made helpful comments on an earlier draft. Argentina. Buenos Aires: FUCEMA, SAREM, Alvaro Jaramillo and Manuel Marin provided de­ AOP,PN. tails concerning some of the Chilean localities. Chris 13. Gibson, E. (1920) Further ornithological notes Balchin, Guy Kirwan, David Wege and Rob from the neighbourhood of Cape San Antonio, Williams were very helpful and encouraging at vari­ province of Buenos Ayres. Ibis (11) 2: 1-97. ous stages. Lastly, we are most grateful to NBC and 14. Hardy, J. W., Reynard, G. B. & Taylor, T. (1996) Swarovski Optics who have provided a grant to fund voices of the New World rails. Gainesville, further surveys for the species in Santa Cruz. Florida: ARA Records. 15. Hartert, E. & Venturi, S. (1909) Notes sur les References oiseaux de la Republique Argentine. Novit. 1. Barrows, W. B. (1884) On birds of the Lower Zool. 16: 159-267. Uruguay. Auk 2: 109-278. 16. Hellmayr, C. E. (1932) The birds of Chile. Field 2. Blanco, D. & Canevari, P. (eds.) (1992) Censo Mus. Nat. Hist. Publ. Zool. Ser. 19 (Puhl. 308). Neotropical de Aves Acuaticas 1991. Buenos 17. Hellmayr, C. E. & Conover, B. (1942) Catalogue Aires: Ambientes Acuaticos Neotropicales. of birds of the Americas, 1. Field Mus. Nat. 3. Blanco, D. & Canevari, P. (eds.) (1993) Censo Hist. Zool. Ser. 13 (Puhl. 514). Neotropical de Aves Acuaticas 1992. Buenos 18. Johnson, A. W. (1967) The birds of Chile and Aires: Wetlands for the Americas. adjacent regions of Argentina, Bolivia and 4. Blanco, D. & Canevari, P. (eds.) (1994) Censo Peru, 2. Buenos Aires: Platt Establecimientos Neotropical de Aves Acuaticas 1993. Buenos Graficos. Aires: Wetlands for the Americas. 19. Narosky, T. & Di Giacomo, A. G. (1993) Las aves 5. Blanco, D. & Canevari, P. (eds.) (1995) Censo de la provincia de Buenos Aires: distribuci6n Neotropical de Aves Acuaticas 1994. Buenos y estatus. Buenos Aires: Vazquez Mazzini Ed. Aires: Wetlands for the Americas. 20. Navas, J. R. (1962) Reciente hallazgo de Rallus 6. Carp, E. (ed.) (1991) Censo Neotropical de Aves limicola antarcticus King (Aves, Rallidae). Acuaticas 1990. Buenos Aires: International Neotr6pica 8 (26): 73-76. Wetlands & Waterfowl Research Bureau. 21. Oates, E. W. (1901) Catalogue of the collection 7. Collar, N. J., Gonzaga, L. P., Krabbe, N., Madrofto of bird's eggs in the British Museum, 1. Lon­ Nieto, A., Naranjo, L. G., Parker, T.A. & Wege, don, UK: Taylor & Francis. D. C. (1992) Threatened birds of the Americas: 22. Paynter, R. A. (1995) Ornithological gazeteer of the ICBP I IUCN Red Data Book. Cambridge, Argentina. Second edition. Cambridge, Mass.: UK: International Council for Bird Preserva­ Museum of Comparative Zoology. tion. 23. Reed, E. C. (1877) Apuntes de la zoologia de la 8. Collar, N. J ., Crosby, M. J. & Stattersfield,A. J. Hacienda de Cauquenes, provincia de (1994) Birds to watch 2: the world list of threat­ Colchagua. Anales de la Universidad de Chile ened birds. Cambridge, UK: BirdLife Interna­ 49: 535-569. tional (Conservation Series 4). 24. Scott, W. E. D. & Sharpe, R. B. (1904) Reports of 9. Fjeldsa, J. (1988) Status of birds of steppe habi­ the Princeton University expedition to tats of the Andean zone and Patagonia. In Patagonia, 1896-1899, 2: Ornithology, 1. Goriup, P. D. (ed.) Ecology and conservation Princeton: Princeton University Press. of grassland birds. Cambridge, UK: Interna­ 25. Wege, D. C. & Long, A. J. (1995) Key Areas for tional Council for Bird Preservation (Techn. threatened birds in the Neotropics. Cambridge, Puhl. 7). UK: BirdLife International (Conservation Se­ 10. FjiMsa, J. (1990) Systematic relations of an ries 5). asembly of allopatric rails from western South 26. Weller, M. W. (1967) Notes on some marsh birds America (Aves: Rallidae). Steenstrupia 16 (7): of Cape San Antonio, Argentina. Ibis 109: 109-116. 391-411.

100 COTINGA 10 Rediscovery of the Austral Rail Santa Cruz, Argentina

27. Withington, F. (1888) On the birds of Lomas de Zamora, Buenos Aires, Argentine Republic. Ibis (5) 6: 461-473.

Juan Mazar Barnett (AOP) Au. Forest 1531 1°B, 1430 Buenos Aires, Argentina. E-mail: j [email protected]

Santiago lmberti (AOP) CC: 368, (9400) Rio Gallegos, Santa Cruz, Argen­ tina. E-mail: [email protected]

Marco della Seta and German Pugnali (AOP) c I o Asociaci6n Ornitol6gica del Plata, 25 de mayo 749 2°6, 1002 Buenos Aires, Argentina.

IOI