Abstract:
Association two species of hummingbirds with trees of the genus Eucalyptus (Myrtaceae) in the province of Buenos Aires. The importance of Eucalyptus trees, in particular the E. globulus, in the diet of some species of hummingbirds, specially during the winter, has been reported. Field observations carried out in Villa Gesell (on Leucochloris albicollis), Pereyra Iraola and Ezeiza (on Hylocharis chrysura ), indicate that this association is also present in the province of Buenos Aires. Our observations during late autumn lend support to the belief that both hummingbird species are permanent residents in Buenos Aires province. However, this has not been clearly stated in the bibliography. On the contrary, there are opposed opinions regarding whether the H. chrysura is or is not a permanent resident, while available data on L. albicollis are insufficient to shed a definite light on the matter.

Abstract:
An incubation period of 15 days and a nestling period of 21-23 days were recorded for the hummingbird Chlorostilbon aureoventris. Data on nestling weight and growth are inc1uded. In a nest visited by 2 fema1es, 3 nestlings were successfully reared.

Abstract:
This paper is the result of field research on the Southern Lapwing ( Vanellus chilensis ) carried on a study site in Las Heras, Province of Buenos Aires during the breeding season 1983-1984. Alarm and brood defence displays and vocalizations are described and discussed. A "militar display" seems to be territorial. Territory size was estimated by trhee methods.

Abstract:
The host-parasite interactions between Chalk-browed Mockingbirds ( Mimus saturninus ) and Shiny Cowbirds ( Molothrus bonariensis ) were studied around Villa María, Córdoba, Argentina, between 1979 -1984. The incidence of parasitism was 81/92 or 88,04%. Mockingbirds in the study site accepted Cowbird eggs, even those of the immaculate morph, which are rejected in Buenos Aires. Incubation period for the host was 14-15 days, for the parasite 12-13 days, with nestling periods of 13 -14 and 14 -15 days respectively. Breeding season of host and parasite overlapped almost completety. In a better studied subsample of parasitized nests success for the host was 7,70% (ratio Fledglings//eggs of 3/39) and for the parasite 6,45% (2/31). Cowbirds punctured and removed host eggs. Mockingbirds were probably the best local hosts for the Cowbirds.

Abstract:
GUIDE FOR THE CODIFIED THE EXTERNAL AND OTHER ADDITIONAL CHARACTERS OF THE BIRDS FOR ETHOLOGICAL STUDIES: THEORETICAL AND METHODOLOGICAL FOUNDATIONS. In this paper, the authors intends to explain the theoretical and methodological foundations refered to the further study or exhaustive analysis of the exosomatic characteristics and other complementary data for to research of the animal behaviour and display patterns (specially in birds, at the present), and its aplicattions in the human ethological studies. Will be presented, in other future contributions, the analitical development of the results obteined, in order to made the adjusting the theoretical and methodological foundations here proposed.

Abstract:
A nest of the Planalto Hermit ( Phaetornis pretrei) was found near Tartagal, Salta, Argentina. It was built within a culvert in a dirt road in the forest. The location of the nest resembles those used by the closely related Ph. augusti in Venezuela.

Abstract:
Nesting Straight-Billed Reedhaunters (Limornis rectirostris) were found in Benavídez, Province of Buenos Aires, in a marshy tract near the Río Luján. Eryngium eburneum was one of the numerically importan plants in the site. The bird's bill is probably adapted to extract prey from the bromeliad-like rosettes of this plant. The bird is somewhat creeper-like in its habits, resembling at times Cranioleuca pyrrophia . A single nest was found, built in an Eryngium , ellipsoidal in shape with a side entrance; it contained 3 white eggs. The findings agree with thc only other nest described in the literature.

Abstract:
During a field work conducted from 1 to 20 February 1984 in Península Mitre, Isla Grande, Tierra del Fuego, Argentina, 83 species were recorded from the península or adjacent waters while aboard the ships during navegation along Canal Beagle, Canal Moat and Estrecho Le Maire. Information is presented on: Phalacrocorax atriceps, Chloephaga hybrida, Chloephaga rubidiceps, Tachyeres pteneres, Anas sibilatrix, Anas bahamensis, Circus cinereus, Polyborus australis, Falco peregrinus, Falco femoralis, Charadrius falklandicus. Pluvianellus socialis, Calidris canutus, Calidris alba, Calidris fuscicollis, Calidris bairdii, Thinocorus orbigniyanus. Chionis alba, Asio flammeus, Cinclodes antarcticus. Cinclodes oustaleti, Lessonia rufa, Notiochelidon cyanoleuca, Anthus correndera and Sicalis lebruni .

Abstract:
The present work is a report of observations realized upon a nesting asociation located over a sand-bank in the Uruguay River, Province of Entre Ríos, Argentina, giving a description of nests; eggs, nestlings and nesting behavior of Charadrius collaris , Sterna superciliaris and Rynchops nigra . Its relative low success in nesting is tentative explained by the fact of being in the last period of the breeding season and also by losses of eggs due to the action of periodical overflow of waters.

Abstract:
The Ultramarine Grosbeak (Cyanocompsa cyanea) is reported for the first time for Buenos Aires Province. Data on the general distribution of the species in Argentina (particulary Entre Ríos) is given.