New Subspecies of Birds from the Lowland Pine Savanna of Northeastern Nicaragua

Abstract

PINE forest reaches the southern limit of its natural distribution in the western hemisphere within the boundaries of Nicaragua, where three species of Pinus-oocarpa, pseudostrobus, and caribaea-occur. Pines are found in three separate areas in Nicaragua, two of which are montane. There is an isolated stand of P. oocarpa on the upper slopes of Volcan San Crist6bal and Volc/m Casita, in the Department of Chinandega in the northwestern part of the country. All three species are found in scattered localities in the north-central highlands, which extend from the Honduras border south to the valley of the Rio Grande de Matagalpa. P. pseudostrobus is the least common form and occurs only at elevations between 1,200 and 1,700 m; P. oocarpa is the most abundant montane species and is found from 600 to 1,700 m; P. caribaea is less widely distributed in the mountains and occurs at elevations from 400 to 900 m (Denevan, 1961; Taylor, 1963). In northeastern Nicaragua, completely isolated from the montane forests, is a lowland pine savanna in which the altitude is generally less than 100 m and where only P. caribaea is found (Figure 1). This savanna covers most of the Comarca de E1 Cabo and extends south into the Department of Zelaya in a narrowing, irregular strip along the eastern edge of the Caribbean lowlands a short distance inland from the coast; the southernmost pines are found between the Laguna de Perlas and Bahia Bluefields. The savanna extends north beyond the Rio Coco into eastern Honduras about as far as Cabo Camar6n; its precise limits in Honduras have recently been determined, and it is not continuous with the upland pine forests of that country. Throughout the savanna there are islands and incursions of low-land evergreen rain forest, particularly along watercourses. A much more detailed discussion, with maps, of the ecology and distribution of pine forest and other major vegetation zones in Nicaragua is given by Taylor (1963); Parsons (1955) and Radley (1960) discuss at length the geography of the lowland pine savanna. HISTOIlICAI, I•TROV•JC•O• Although the lowland pine savanna of northeastern Nicaragua and adjacent Hon-duras constitutes a distinctive habitat, isolated from similar formations and utterly different from the adjacent rain forest, it has remained almost unknown ornithologi-cally. The Rio Coco (also known as the Rio Segovia and the Wanks River), which forms part of the present boundary between Honduras and Nicaragua, was visited by C. H. Townsend from June to August, 1887, and a report on his collection of birds was made by Ridgway (1888). No precise locations or habitat descriptions were given, but Townsend's collection included species typical of pine savanna. Only a small hum-438 The Auk, 82: 438-464. July, 1965