Pulsatrix

Abstract: We review all of the fossil specimens from the upper Pleistocene Rancho La Brea asphalt deposits previously referred to the extinct owl Strix brea, and all newly identified specimens referable to that species. This review and emended description of Strix brea have provided a clearer picture of this species, and we find that it is more appropriately placed in a new genus, Oraristrix, whose affinities remain unclear. We provide a variety of morphometric data and more detailed osteological descriptions of this extinct owl based on 138 specimens from the Rancho La Brea collections in the George C. Page Museum that represent a minimum of 23 individuals. An additional nine specimens of this extinct species were confirmed in collections from the upper Pleistocene asphalt deposits of Carpinteria, California. Oraristrix brea is interpreted as being more terrestrial in habits than forest owls because, compared to available species of the genera Bubo and Strix, it had longer legs relative to its wingspan. Campbell Jr., Kenneth e., & Zbigniew m. boChensKi, 2010. A new genus for the extinct Late Pleistocene owl Strix brea Howard (Aves: Strigiformes) from Rancho La Brea, California. In Proceedings of the VII International Meeting of the Society of Avian Paleontology and Evolution, ed. W.E. Boles and T.H. Worthy. Records of the Australian Museum 62(1): 123–144. A large, extinct owl from the upper Pleistocene asphalt deposits of Rancho La Brea, California was described as Strix brea Howard, 1933. In addition to the holotypic tarsometatarsus, several other elements of the skeleton were briefly described and referred to this species by Howard (1933). However, since its original description, with the exception of being included in faunal lists (e.g., Howard, 1962), this species, which is known as the Brea Owl, has not been revisited. Herein we reevaluate the characters Howard (1933) used to distinguish the species, describe additional characters, illustrate bones not previously illustrated, and add to the list of elements and specimens referable to this extinct species. We offer suggestions as to the size and life habits of the Brea Owl based on its osteology and limb bone proportions. Strix brea is found to be a valid species, but one best placed in a new genus. This study is part of an overall review of all of the fossil owls in the collections from Rancho La Brea maintained at the George C. Page Museum by the Natural History Museum of Los Angeles County (LACM). At least nine species of owls are represented in the collections by a total of over 7500 specimens. In the course of this review we found that the post-cranial elements of the genera of owls could be fairly easily distinguished by osteological characters, at least for the 124 Records of the Australian Museum (2010) Vol. 62 several genera represented in the Rancho La Brea collection. This finding is contrary to that of Olson & James (1991), who, citing an unpublished work by Ford (1967), suggested that post-cranial differences between the various subgroups and genera of owls are very slight or non-existent. Materials and methods The fossil specimens were compared in detail with specimens of modern Bubo virginianus (20+) and all of the numerous fossil specimens of B. virginianus from Rancho La Brea, B. bubo (4), B. africanus (1), Strix occidentalis (8), S. varia (7), S. nebulosa (9), and S. aluco (3). The numbers reflect the largest sample sizes of each species available for comparison. Points on scatter diagrams are often less numerous because of incomplete modern comparative specimens. The genera Ketupa and Nyctea are considered by some (Amadon & Bull, 1988; Wink & Heidrich, 1999; Wink et al., 2008) as properly being included within Bubo, so these genera were included in our study. Nyctea, for the most part, agrees with Bubo as far as the osteological characters useful for distinguishing the Brea Owl from Bubo and Strix are concerned. Ketupa [K. ketupa (1), K. zeylonensis (3)], on the other hand, varies considerably from Bubo osteologically, and we find it to be easily distinguished from both Bubo and the Brea Owl. In our opinion, based on its osteological features, we agree with Sibley & Monroe (1990) that Ketupa is a valid genus separate from Bubo. However, we were unable to compare the species of Ketupa with those Asian species of Bubo that Wink & Heidrich (1999) and Wink et al. (2008) suggested were closest to Ketupa based on molecular studies. Similarly, the genus Ciccaba is considered by some as properly being included within Strix (e.g., Sibley & Monroe, 1990; Wink & Heidrich, 1999; Wink et al., 2008), and we found that two species referred to Ciccaba [C. virgata (1) and C. nigrolineata (1)] agree with Strix as far as most of the osteological characters we detail below are concerned. Based on the osteology of available specimens, we accept that Nyctea belongs within Bubo and Ciccaba within Strix. Comparisons were also made with the genera Tyto, Otus, Megascops, Lophostrix, Pulsatrix, Surnia, Glaucidium, Athene, Aegolius, Micrathene, Ninox, and Asio. Each of these genera can be readily distinguished from Bubo, Strix, and the Brea Owl using osteological characters. In molecular studies, Strix and Bubo appear as closely related taxa (Wink & Heidrich, 1999; Wink et al., 2008), which is reflected in the many osteological characters they share that differ significantly from those of the other genera examined. Therefore, because this study was not intended as a comparative osteological review of all genera of owls we limit our detailed comparisons to species of Bubo and Strix, the genera that most closely resemble the Brea Owl osteologically. Measurements were taken using digital calipers accurate to 0.01 mm, and all data were captured directly to computer. The measurements were stored, and the basic statistics, including minimum, maximum, arithmetic mean, and standard deviations, were computed in Microsoft Excel. For illustrations as to how the measurements were taken, see Appendix 2. All bones were checked for ratios useful for differentiating the species, and scatter diagrams of the ratios were prepared using Microsoft Excel and Corel PhotoPaint. Osteological terminology is primarily from Baumel & Witmer (1993). Abbreviations used: Cond. = condylus; Fac. artic. = facies articularis; Lig. coll. = ligamentum collaterale; Proc. = processus; Tub. = tuberulum Figure 1. Holotypic tarsometatarsus of Oraristrix brea (LACM RLB E9379) in (A) anterior, (B) lateral, (C) posterior, (D) medial, (E) proximal, and (F) distal views. Lateral view (G) of distal tarsometatarsus of O. brea (LACM RLB K9623) illustrates the straight posterior edge of the lateral condyle of Trochlea III. Scale bar = 20 mm. Campbell & Bochenski: New genus of extinct Late Pleistocene owl 125

Abstract: We studied the intra- and interspecific responses to playback of pre-recorded calls by five tropical humid forest owl species at La Selva preserve in northeastern Costa Rica from April to September 1995. Response to conspecific broadcast calls differed among species (X² = 24.4; df = 1; P < 0.001): Vermiculated Screech-owls (Otus guatemalae) responded to 47.6 per cent of broadcasts, followed by Crested Owls (Lophostrix cristata, 45 percent), Mottled Owls (Ciccaba virgata, 18.3 per cent), and Black-and-white Owls (C. nigrolineata, 9 percent). Crested Owls (x = 16.37, sd = 2.6), Mottled Owls (x = 11.7, sd = 7.1), and Vermiculated Screech-owls (x = 10.9, sd = 0.9) responded to interspecific playback more than did Black-and-white Owls (x = 2.04, sd = 2) (H = 10.6; P = 0.01). Spectacled Owls (Pulsatrix perspicilata) did not respond at all during our broadcasting period. Both types of response showed some monthly variation. Response to the calling of other owls also depended on ecological variables such as habitat selection, population density, and resource use. Our data suggest that the development of relationships within the tropical owl community at La Selva may have been mediated in part by intra- and interspecific calling.

Abstract: The Spectacled Owl (Pulsatrix perspicillata) seems to be uncommon near the southern limit of the species' range. Here, we report new records for the Spectacled Owl, identify the subspecies, and examine the spatial distribution of records in the southern part of the species' range. We made 50 sightings of at least two adults and six juveniles over 3 yr in a gallery-forest habitat within Estancia Guaycolec, Formosa, Argentina (25°58′S, 58°10′W). We compared the external morphology of the adults found in Estancia Guaycolec with those of the P. p. boliviana, P. p. pulsatrix, and P. p. perspicillata subspecies, and found great similarity with the features of P. p. perspicillata. We also analyzed the vocalizations of an adult recorded at Estancia Guaycolec and found that its calls accelerated towards the end, as has been reported for P. p. perspicillata. Spatial analysis of records from the southern region of the Spectacled Owl's range showed an alignment of the records from the Chaco region alongside ...