| Wood Storki Mycteria americana  I saw this group of 7 individuals making a big turn above us© J. Simón Tagtachian |
Roadside Hawk Buteo magnirostris  © J. Simón Tagtachian |
| Hooded Siskin Carduelis magellanica  A small flock having a bath accompanied by a Creamy-bellied Thrush© J. Simón Tagtachian |
Fork-tailed Flycatcher Tyrannus savana  One of the several juveniles that migrated on the 20th© J. Simón Tagtachian |
| Yellow-winged Blackbird Agelasticus thilius  © J. Simón Tagtachian |
Masked Yellowthroat Geothlypis aequinoctialis  Female© J. Simón Tagtachian |
| Solitary Cacique Cacicus solitarius |
 © Oscar Melo |
| Rufescent Tiger-Heron Tigrisoma lineatum |
 © Roberto Ares |
| Green-winged Saltator Saltator similis |
 © Mariano Ordoñez |
| Fawn-breasted Tanager Pipraeidea melanonota |
 Off-season sighting. This tanager visits us in winter© Pablo Mosto |
| Grayish Saltator Saltator coerulescens |
 © Pablo Mosto |
| Some more insects |
 Go to Invertebrates |
| For-tailed Flycatcher Tyrannus savana Video © Roberto Ares Migración (See in full screen. First right icon on tool bar) We were reaching the cement pitch when a first group of six Fork-tailed Flycatchers, which I could not see, flew past over our heads. They were heading north. A bit later a front of several flycatchers emerged out of the top of the trees which flank the path. Flying low they dodged and mixed with pigeons, martins and other birds that are normally there. In a more or less disorderly way they progressed in a northerly direction and we lost sight of them. And a new wave appeared and so went on the bouts with dozens of flycatchers each. We were amazed at the number of individuals thay flew past. It was a feast. Some sat for a while on a branch and resumed flight with the same group or with the following one. Juvenile and female tails (18cm) outnumbered male tails (34 cm), a considerable difference in size. Several males had one of their rectrices broken. One of them was filmed during a stop. Such a flow of individuals could be nothing else but migration. In their migration route to the south the groups which spread out from the principal trunk aggregate again on their return trip gathering at roosting sites. Now in bigger quantities since juveniles born here also join the group. Is Costanera one of these favoured sites? For my part, this is the first time I have seen the migration of Fork-tailed Flycatchers. Of course, this is so short a time window that one must be at the right time and place to witness it. There are four subspecies of Fork-tailed Flycatchers having different migratory behaviour. The one that migrates to Argentina (Tyrannus savana savana) comes from the northern extreme of South America and is highly migratory. There is a transient species and the other two are resident. Tyrannus savana savana arrives in September-October to spend summer. Here it breeds and returns in February-March to winter in the north. Last year’s first photographic record was in October. Today, the 20th of February we saw them leave. Text: Cora Rimoldi |
| Campo Troupial Icterus jamacaii  The “cousins”…© Carlos Gonzalez Ledo |
Orange-backed Troupial Icterus croconotus  are still together© Carlos Gonzalez Ledo |
| Red-eyed Vireo Vireo olivaceous  © Carlos Gonzalez Ledo |
Narrow-billed Woodcreeper Lepidocolaptes angustirostris  Particular position of the legs to grasp onto this smooth light pole.© Carlos Gonzalez Ledo |
| Cigüeña americana Ciconia maguari  It flew around the reserve trying to land. But finally it did not.© Carlos Gonzalez Ledo |
Monk Parakeet Myiopsitta monachus  Eating the flower of Silk Floss Tree Ceiba speciosa© Carlos Gonzalez Ledo |
| Glittering-bellied Emerald in trouble | |
 © Javier Ubiría |
 © Javier Ubiría |
| Norberto heard the desperate screamings of the juvenile Emerald. It was caught in the resistent spider of the nephila (one of the most resistent among the arachnids). The web was big. The hummingbird very small and light. It could not have freed by its own means. When we detected the presence of the spider (unluckily out of frame) 20 cm away, Norberto rushed to rescue the hummingbird. His prompt action lasted a few seconds. He swiped it off and released it. The Emerald was exhausted and shocked. It stayed in his hand till it recovered and flew off. The “bad” spider was about to kill the “good” hummingbird. I did not intend to interfere in a natural process. In a phenomenon which is apparently cruel and merciless. The observer must watch without interfering. Again the eternal game between life and death. The prey’s death which means the predator’s life. Javier Ubiría |
|
| New bird species: Dark-throated Seedeater Sporophila ruficollis |
 Juvenile photographed in october 201110-2011© Pablo Mosto |
| Scissor-tailed Nightjar Hydropsalis torquata |
 Photo taken in 2011. But it is worth watching the details of this female Scissor-tailed Nightjar so exposed in broad daylight. The Nightjar becomes active at dusk so poor light prevents us from having a good look at it.2-2011 © Rosana Ursino |
| Chotoy Spinetail Schoeniophylax phryganophilus |
 © Pablo Mosto
|
| The Chotoy Spinetail appeared from time to time at Costanera. Last October it popped up and stayed to breed. During that time it was difficult to capture images since it moved surreptitiously so as not to be discovered. Here, instead, we can fully appreciate this relative of the Rufous Hornero. Long tail with two spines. Rufous crown and shoulders. Yellow chin and black throat flanked white. CR |
| Ferruginous Pygmy-Owl Glaucidium brasilianum |
|
 © Pablo Mosto |
 © Pablo Mosto |
These two photos were taken a bit before the video. Pablo told us about the pygmy-owl. The prey is a juvenile of Small Elaenia |
| Caburé chico Glaucidium brasilianum Aves non gratae Among the bird species present at Costanera the Southern Caracara and the Ferruginous Pygmy-Owl are considered unwanted because they prey on birds, among other things. The birds know the risk they run when either of them are close. So they take courses of action that differ from one another. The Southern Caracara is stalked either solitarily or in pairs by the Chalk-browed Mockingbird (25 cm) and the Fork-tailed Flycatcher (38 cm) among other birds. They mob on the Caracara till it is driven away. It is chased and even pecked at on the wing. It seems funny to see how the big Caracara is driven away by a much smaller bird. In this case there was a Red-eyed Vireo, a male Masked Yellowthroat, a Small-billed Elaenia, a Streaked Flycatcher (not appearing in the video), three Masked Gnatcatchers and several Emeralds (definitely some females). All of them sounded very altered. The feathered ball which appears under the branch is the juvenile Small-billed Elaenia of the above photos. It held it tightly with the claws and stood motionless only moving its head to keep visual contact with the birds flying by. None of them attacked the owl. They only put pressure by flying very close to it. At a point it moved to another branch and stood there for a while till it left. Video © Roberto Ares – Texto Cora Rimoldi |
|
| Blue-billed Black-Tyrant Knipolegus cyanirostris |
|
 Female© Pablo Serur |
 Female© Pablo Serur |
| South American Snipe Gallinago paraguaie  © J. Simón Tagtachian |
Ringed Teal Callonetta leucophrys  Pair© J. Simón Tagtachian |
| Ringed Teal Callonetta leucophrys  In flight circular white patch is seen© J. Simón Tagtachian |
|
| Brazilian Teal Amazonetta brasiliensis  In flight white triangular patch and blue speculum are seen© J. Simón Tagtachian |
|
| Glittering-bellied Emerald and Gilded Sapphire Chlorostilbon aureoventris – Hylocharis chrysura If in flower is the silk floss tree hummingbirds around you’ll see The Silk Floss tree Ceiba speciosa at the Viamonte Access is loaded with flowers. Joy to our eyes and a nutritious food source for the hummingbirds. There were a Gilded Sapphire (bronze colour) and a female Glittering-bellied Emerald (with grayish underparts), some time later a male showed up, too. The Gilded Sapphire defended from the competitors what it considered its tree. As the Sapphire identified an intruder it pounced on it to drive it away. The intruder reacted by escaping and the Sapphire escorted it to make sure it left the grounds. But success was temporary since the Emerald was back in no time and the sequence was repeated. When the male Glittering-bellied Emerald showed up things got worse for the Sapphire, now there were two intruders to be expelled from its territory. The movement of hummingbirds is so fast that only these scenes could be rescued. Among them, two chases © Roberto Ares – Text: Cora Rimoldi |
| February 2nd – World Wetlands Day |
| This day in 1971 in Ramsar, Iran, a treaty on wetlands was signed. It provides a framework for the conservation and sustainable use of their resources. Wetlands are defined as extensions where water is a crucial element and its regime (permanent or temporal water, tides, etc.) defines the structure and ecological functions of the place, be it lakes, rivers, swamps, marshes, marine areas, man-made sites, etc. Argentina joined the Convention on 4th of September 1992. The first site was the Monumento Natural Laguna de los Pozuelos in Jujuy. Reserva Costanera is the 14th site and was included on the list on 22nd of March 2005. Nowadays Argentina has 20 sites on the list. Joining the Convention implies a commitment on the part of the National Government to actively work to secure conservation and sustainable use of the area in question. |
Comments