SHORT COMMUNICATIONS ORNITOLOGIA NEOTROPICAL 17: 467–472, 2006 © The Neotropical Ornithological Society DIET OF THE CHILEAN TINAMOU (NOTHOPROCTA PERDICARIA) IN SOUTH CENTRAL CHILE Daniel González-Acuña1, Paulo Riquelme Salazar1, José Cruzatt Molina1, Patricio López Sepulveda2, Oscar Skewes Ramm1, & Ricardo A. Figueroa R.3 1Facultad de Ciencias Veterinarias, Departamento de Ciencias Pecuarias, Universidad de Concepción, Chillán, Chile. E- mail: [email protected] 2Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Casilla 160- C, Universidad de Concepción, Concepción, Chile. E- mail: [email protected] 3Estudios para la Conservación y Manejo de la Vida Silvestre Consultores, Blanco Encalada 350, Chillán, Chile. E- mail: [email protected] Dieta de la Perdiz chilena (Nothoprocta perdicaria) en el centro-sur de Chile. Key words: Diet, gramineous, Nothoprocta perdicaria, Chilean Tinamou, Poaceae, Chile. Studies of bird diet have been important for report for the first time the Chilean Tinamous understanding their life history and ecological diet in the Ñuble Province, south central requirements. However, few dietary studies Chile. Our objective was to determine if the have been carried out on Tinamiform birds, Chilean Tinamou is a tropically generalist or and particularly on species of the Nothoprocta specialist species. genus (Cabot 1992; Mosa 1993, 1997; Gari- We analysed the contents of crops and tano-Zavala et al. 2003). In fact, no study is stomachs obtained from 79 birds captured in available for Chilean Tinamou (Nothoprocta different agricultural areas, years, and seasons perdicaria) (Cabot 1992, Jaksic 1997), and the (Table 1) in the Ñuble Province, south central only study on its diet has not been published Chile (Fig. 1). Ñuble province has a Mediter- (Rottmann unpubl.). The scarce information ranean temperate climate with an average on the food of Chilean Tinamou suggests that temperature of 13.5ºC and an average annual it has a mixed diet, including plant material precipitation of 1055 mm (Del Pozo & Del and small invertebrates (Housse 1945, Egli & Canto 1999). Ñuble Province corresponds to Aguirre 2000). a transitional zone between the dry scrubland Ecological studies on the Chilean of central Chile and the temperate rainforest Tinamou are prioritaries because it is an of southern Chile with a high diversity of endemic bird to Chile (Araya & Millie 2000) flora and fauna (Muñoz et al. 1996). and its population seems to be declining in Although we analysed crops and stom- number as a result of intensive hunting achs, contents of the latter only included a lit- (Cabot 1992, Egli & Aguirre 2000). Here, we tle mineral and vegetal material; thus, our 467 GONZÁLEZ-ACUÑA ET AL. TABLE 1. Information about the Chilean Tinamou (Nothoprocta perdicaria) (N = 79) captured in agrosystems for dietary analysis in Ñuble Prov- ince, south central Chile. Seasons Years Number of birds Summer 1995 10 Summer 1995 24 Winter 1999 12 Winter 2000 18 Winter 2001 15 Total of birds 79 results reflect instead information from crops. Crops contents were dried for 24 h at 30ºC. FIG. 1. Agricultural localities where the 79 Chil- The seeds collected from crops that could not ean Tinamous (Nothoprocta perdicaria) were capture be identified were germinated. Each food for crop and stomach content analysis. Pemuco item was quantified based on its proportional (1), El Carmen (2), San Ignacio (3), Coihueco (4), occurrence (O), number frequency (NF), and San Carlos (5), Ninhue (6), Pinto (7), Chillán (8), Portezuelo (9), San Nicolás (10), and San Fabián biomass (B). The taxonomic classification of (11). plant species follows Finot & Bravo (1985), Marticorena & Quezada (1985), Matthei (1995), and Finot (1997). The food-niche 19.2%, NF = 25.9%, B = 31.5%), Fabaceae breadth (i.e., diet diversity) for each season (O = 19%, NF = 24%, B = 22%) and Polygo- was calculated according to the Shannon- naceae (O = 12.8%, NF = 25.5%, B = 7%) Wiener index (H, Krebs 1989) and were sta- were the most common in the diet. The most tistically compared by the Hutcheson t-test important species by occurrence, number, (see Zar 1984). Differences in seasonal con- and biomass were Convolvulus arvensis and sumption of plant and animal material were Polygonum aviculare (Table 2). P. aviculare was evaluated with chi-square tests using contin- dominant in number and relatively important gence tables (Zar 1984). in occurrence, but its biomass contribution Diet consisted mainly of wild plant seeds was smaller (Table 2). (Table 2). The consumption of animal mate- After combining the results from both rial was scarce and consisted of one insect seasons, the Poaceae seeds constituted the and crustacean species (Table 2). During the diets main component either in occurrence, summer, the seeds of the Poaceae family were number and/or biomass (Table 2). Polygo- most common, among which Panicum capillare naceae seeds were second in importance and the Lolium sp. were the most consumed. (Table 2). Even though the Fabaceae seeds Although, in terms of occurrence, Lolium sp. were important in terms of occurrence, their had higher importance than P. capillare, the number and biomass were low (Table 2). P. seeds of the latter were dominant in terms of capillare and Lolium sp. were once gain the number and biomass (Table 2). During the most consumed taxa (Table 2). Other rela- winter, the seeds of Convolvulaceae (O = tively important species in occurrence were P. 468 SHORT COMMUNICATIONS TABLE 2. Diet of the Chilean Tinamou (Nothoprocta perdicaria) determined by analysis of stomach and crop contents in Ñuble Province, south central Chile. N = Number of birds, O% =Frequency of occur- rence, NF% = Percentage of number frequency, B% = Percentage of biomass. Dietary items Summer (N = 34) Winter (N = 45) Combined (N = 79) O% NI% B% O% NI% B% O% NI% B% Asteraceae Ambrosia sp. 2.5 0.1 0.3 3.2 1.3 0.8 2.8 0.2 0.3 Centaurea melitensisa 0.8 0.1 0.1 0.8 1.6 8.6 0.8 0.2 2 Cirsium sp. 0.8 0.1 0.2 0 0 0 0.4 * 0.1 Crepis sp. 1.6 0.4 1.4 0 0 0 0.8 0.4 1.1 Boraginaceae Echium vulgarea 1.6 0.5 0.7 0 0 0 0.8 0.5 0.5 Brassicaceae Brassica campestrisa 3.3 0.1 0.1 0 0 0 1.6 0.1 * Raphanus sp. 0.8 * 0.4 0 0 0 0.4 * 0.3 Chenopodiaceae Chenopodium albuma 0.8 0.4 0.1 0 0 0 0.4 0.4 0.1 Chenopodium sp. 0 0 0 8 3.7 3.3 4.0 0.2 0.7 Convolvulaceae Convolvulus arvensisa 1.6 0.1 19.0 26.0 31.5 11.0 1.6 7.0 Fabaceae Galega officinalisa 0 0 0 1.6 1.4 5.5 0.8 0.1 1.2 Trifolium subterraneumb 0 0 0 0.8 0.2 0.3 0.4 * * Medicago polymorphaB 0 0 0 6.4 21.0 9.8 3.2 1.3 2.2 Vicia sativab 0 0 0 10.0 1.7 6.3 5.3 0.1 1.0 Lathyrus sativusb 0.8 * 1.7 0 0 0 0.4 * 1.3 Lathyrus sp. 0 0 0 0.8 * 0.1 0.4 * * Lens culinarisb 0 0 0 0.8 * 0.1 0.4 * * Vicia sp. 3.3 * 0.3 0 0 0 1.6 * 0.2 Malvaceae 0.8 0.1 0.2 0 0 0 0.4 * 0.2 Mimosaceae Acacia sp. 1.6 * 0.1 3.2 6.6 15.2 2.4 0.4 3.3 Oxalidaceae Oxalis sp. 0.8 * 0 7.2 2.3 1.0 4.0 0.1 0.2 Polygonaceae Polygonum avicularea 2.5 2.8 2.7 13.0 26.0 7 7.7 4.2 3.6 469 GONZÁLEZ-ACUÑA ET AL. TABLE 2. Continued. Dietary items Summer (N = 34) Winter (N = 45) Combined (N = 79) O% NI% B% O% NI% B% O% NI% B% Polygonum sp. 5.0 2.7 3.3 0 0 0 2.4 2.6 2.6 Ranunculaceae Margyricarpus sp. 0 0 0 0.8 * * 0.4 * * Cyperaceae Carex sp. 0.8 0.5 1.3 0 0 0 0.4 0.5 1.1 Poaceae Avena sativab 0 0 0 0.8 * 0.1 0.4 * * Bromus hordeacusa 3.3 0.4 3.3 0 0 0 1.6 0.4 2.6 Echinocloa crusgallia 0 0 0 0.8 0.2 0.1 0.4 * * Echinocloa sp. 4.9 3.0 4.5 0 0 0 2.4 2.9 3.5 Hordeum sp. 3.3 0.3 0.7 0 0 0 1.6 0.3 0.5 Lolium multiflorumb 0.8 * 0.1 0 0 0 0.4 * * Lolium sp. 17.6 16.3 25.2 8.0 2.5 1.4 12.5 15.5 20.3 Panicum capillarea 8.2 70.9 38.4 7.2 4 1.1 7.7 66.7 30.4 Triticum sp.a 5.0 0.2 3.8 0 0 0 2.4 0.2 3.0 Unidentified seeds 12.3 1.0 9.0 6.4 2.2 7.3 9.3 1.0 8.6 Total of seeds (84.4) (99.9) (98.0) (99.2) (99.8) (99.5) (91.9) (99.9) (98.2) Animal material (15.6) (*) (2.0) (0.8) (*) (0.5) (8.1) (*) (1.7) Insects Dichropus araucanus 12.3 * 1.9 0 0 0 6.1 * 1.5 Crustacea Julus terrestris 3.3 * 0.1 0.8 * 0.5 2.0 * 0.2 Total frequency 122 125 247 Total No. of items 66247 4472 70719 Total mass (g) 135.8 37.1 172.9 aWeed seeds.