Pampas Meadowlark Leistes defilippii Scientific name definitions

The Pampas Meadowlark is unusual for a meadowlark, it is the one species that has not been able to adapt well to agriculture and human related changes to the environment. Other meadowlarks have become more common and some are even spreading in distribution as forests are cut, and agriculture takes over, but it is quite the opposite for the Pampas Meadowlark. It has become rare, in fact it is highly endangered and officially listed as Vulnerable. Maps of its distribution show a wide range from southern Buenos Aires province in Argentina clear up to southernmost Brazil in Rio Grande do Sul, and this is correct but misleading. The species is very local and it is only found in fragmented populations throughout its historical range, although in the north these are very precarious. Right now the stronghold of the Pampas Meadowlark is southwest Buenos Aires province and adjacent La Pampa. The issue is that this meadowlark needs tall, “old growth” grassland and does not breed in agricultural areas or those with intensive cattle ranching. These natural grasslands are harder and harder to find, and are easily converted to other uses. It is estimated that when much of this part of the world was a huge tall-grass prairie, the Pampas Meadowlark may have been one of the most common species in the region! While the meadowlark can coexist with some cattle ranching, it cannot be intense, and it does not breed in planted non-native grasses. Preservation of habitat for this bird would in effect preserve a bit of the original Pampas, not only ecologically significant, but culturally significant to the nations of this region.

Male average 21 cm, 73·6 g; female 67·5 g. Male has head and side of neck black, long white superciliary  line becoming red in front of eye, white submous­tachial stripe  and lower eyelid; otherwise mostly dusky brown with brownish streaks above, uppertail-coverts barred, tail blackish with thin olive barring, marginal and a few lesser upperwing-coverts rosy red; chin  to belly rosy red, side of breast, flanks and vent black, underwing-coverts black, with red marginal coverts; in fresh plumage (non-breeding) black areas above more prominently streaked brown, supercilium more buff, upperwing-coverts pale-tipped, red of underparts obscured by buff or olive feather tips; bill silver-grey, culmen and tip dark; legs dark brown. Differs from similar L. loyca in stockier build and shorter tail, less striped appearance, in flight also by black underwing-coverts. Female  is paler and browner than male, with white throat, and streaked underparts enclosing pale pink-red lower breast. Juvenile is like female, but no red on underparts, and bill horn-coloured.

N & C Uruguay (Salto and Flores (1 Azpiroz, A.B. (2015). Shiny Cowbird (Molothrus bonariensis) parasitism records for three globally threatened species from the South American Pampas. Wilson J. Orn. 127(4): 746–752. Close ) Departments) and CE Argentina (SW Buenos Aires, La Pampa and Río Negro); no recent records from Brazil.

Native grasslands and pastures; only rarely in agricultural fields. Most individuals (82% of extant population) nest in natural grassland, the rest in agricultural fields; grasslands used for nesting in Argentina include Baccharis (Asteraceae) and grasses in genera Stipa and Piptochaetium. Uruguayan population breeds in native grassland mixed with carqueja (Baccharis trimera). Agricultural land abandoned for five years or more becomes increasingly suitable for nesting. Can live in treeless areas, and seldom perches on shrubs or fences. Lowlands to 900 m.

The few reliable Brazilian records sometimes interpreted as representing seasonal movements; recent research on main population in Argentina suggests year-round resident. Further research needed.

Insects and seeds. Contents of three stomachs included beetles (of families Scarabaeidae and Curculionidae) and seeds. Forages in small groups; in non-breeding season moves in flocks of some hundreds (formerly thousands, then compared to marching armies).

Male flight song variable and rather musical, often combining ascending and descending whistles with a loud sustained note, e.g. “tse-tse-réé-tsew-tsee-tsew”, last notes rather soft; perched song (from low above ground, mostly on bunch-grass) includes final buzzy or rasping notes, resembling those of L. loyca. Call “peet”, also a rasping note  .

Season Oct–Nov in Argentina. Mating system unstudied. Breeds in “reproductive groups” or dispersed colonies, nests more clumped than those of L. loyca; colonies contain 2–66 displaying males in Argentina, 3–25 in Uruguay. Male defends rather small territory, mean inter-nest distance in one study 23 cm. In flight display male flies upwards to c. 7 m, and then descends while singing. Nest a cup built from plant material, external diameter 9·5 cm, placed within depression on ground, near a grass clump, may have entrance corridor c. 8 cm long. Clutch 3–5 eggs, mean 3·14 eggs in recent study, variable, buff to grey with darker spots, blotches and lines, mean dimensions 25·8 × 18·3 mm; no information on incubation period; chicks fed mostly by female, nestling period c. 10 days; male possibly feeds fledglings. Parasitized by Molothrus bonariensis, but far less frequently than L. loyca; apparently female of this brood parasite find nests of present species hard to locate. Nesting success: in one study 29% of eggs produced fledglings.

VULNERABLE. Rare to locally uncommon. Nowadays found mostly around Sierra de la Ventana, a low (1200 m) range of rocky mountains in SW Buenos Aires, in Argentina; one population in N Uruguay. Formerly occurred in extreme SE Brazil (coastal Rio Grande do Sul), more widely in Uruguay, and in at least seven provinces in CE Argentina (S Cordoba, San Luis, E La Pampa, Corrientes, Santa Fe, Entre Ríos and Buenos Aires ). Has declined considerably in range and numbers in both Argentina and Uruguay. In 1870s and 1890s flocks of many thousands reported in Buenos Aires pampas, particularly in territories recently taken from the native Indians; was still reported as a regular breeder throughout pampas up to early 1950s, but thereafter seriously declined. Main stronghold now SW Buenos Aires province, around Sierra de la Ventana and nearby ranges, where rocky soils do not favour ploughing and agriculture; recent surveys in this area have shown that population may approach 28,000 individuals. Uruguayan population much smaller, c. 200 individuals, and perhaps isolated. The possibility that similar isolated populations may be found elsewhere within its historical range merits investigation. Main cause of this species’ rapid decline is replacement of natural grasslands with crops and planted pasture; interspecific competition with two sympatric meadowlarks (L. superciliaris and L. loyca) may also play a role. Capture for trade appears not to be an extensive problem, although, in 1988, more than 100 individuals of this species were seen in local markets. Breeding areas of this species mostly unprotected, but a few may be found in provincial reserves.