The very first week of December 2002 took me out into the Pampas to make a productivity survey of the forthcoming wheat harvest and the field progress of coarse crops sowings of corn, soybeans and sunflower. The fields were dispersed throughout the provinces of Santa Fe and Buenos Aires totalling 11.500 hectares (27,600 acres) giving me a very good chance to make some fine and varied birding in the flat lands (Pampas) and hilly areas of Tandil and Balcarce.
I had an excellent trip with fine and very warm weather and although this is an "El Niño" year, the rains spared me. Everywhere brooks, rivers, ponds and lakes are full of water to the delight of waterfowl and ducks that this year seem to be over-abundant. Readers should see below April 2002 for the birds I mention during our Fall season, while this Birding Report deals with late Spring sightings and and I'll list mainly new birds seen on this ocasion. Birds seen:
While driving in southern Santa Fe province, we turned onto a mud road and to my surprise a very dark (black) long-tailed bird took off from a nearby field and flew into a tree. Stop! Stop and go back! was my first reaction. Carefully I came out of the car and went slowly towards the tree. There, on a low branch a Smooth-billed Ani was peeking out at me. We both stared at each other and then the Ani decided it had enough and flew away into the open and then vanished behind some bushes near a fence. It gave me an excellent view and as it is a bird belonging to much more north-eastern areas in the country, I came to the conclusion that I had seen a vagrant. The commotion was great!
Smooth-billed Ani, Crotophaga ani. Glittering-bellied Emerald, Chlorostilbon aureoventris. Green-barred Woodpecker, Colaptes melanochloros. Tropical Kingbird, Tyrannus melancholicus.
While in the Balcarce Hills, we stopped to have lunch at a very nice place beside a small lake called "Laguna La Brava". We had some steaks (a must in Argentina!) served on a roofed veranda. My attention was drawn by several birds flying around and trying to get into a side hole in the roof. They certainly were dark Martins and when some of them flew from the surrounding trees shade into the sunlight, a beautiful metal blue glint gave them out as being male Purple Martins mingling with several females which resemble very much a Grey-breasted Martin.
A nice surprise was to see everywhere large numbers of Swainson's Hawks soaring majestically in the blue sky or feeding on the ground looking for locusts and other insects. It was very interesting to watch flocks of Brown-hooded Gulls overflying wheat fields and picking in flight at catterpillars that were eating the grain on ripe wheat panicles, quite a sight! Also I saw mainly in the fields in the Balcarce area several Long-tailed Meadowlarks, a very scarce bird in other years.
The Pampa Fields - April 2002
The week before Easter took me into the Pampas. I had to do a productivity survey of maize and soybeans crops before the oncoming local coarse grains harvest. Many of the fields visited were separated one from the other by large distances, so I went into several provinces mainly southern Santa Fe and northern Buenos Aires and also into the Balcarce Hills that lie in the latter's southeast quite near a sea resort known as Mar del Plata.
During my whole week travelling the weather was warm with clear skies that not only helped me in my task but also allowed me to do some birdwatching. Fall season started at the very beginnings of my trip, so I expected some mild and fresh weather mainly in the southeastern Pampas area and many of the birds to have moved into the more warm northern parts of the country. While travelling this was confirmed in the fields although I managed to see some delayed birds that were still wandering in the places, taking advantage of food available in the warm and sunny days. Frequent rainfalls during the whole summer season helped flood many lowland fields that were taken over by waterfowl and shore birds. By the time of my trip, the northern migrants had already left so I did not see any of them. While walking through soybeans fields, in several places Spotted Tinamous took off with their typical "squeak" whistle as they blasted out with their wings beating fast seeking the wind to help them fly even faster away.
Some early harvested corn/maize crops usually have grains left on the ground mostly spilled by the harvesting combines. This gives mainly ducks and pigeons a fantastic opportunity to feed and also brings birds of prey that come to seek out the weaker birds. Because of the abundance of water shelter caused by the summer rains, the duck flocks were very large. I managed to see:
The behaviour of the birds of prey is always entertaining, mostly when they are feeding. On several occasions I saw the White-tailed Kites to stop in the air beating their wings and look down into the grass and then suddenly drop onto the ground yet not always come back flying with 'something' hanging in their claws. On another day, I was walking bordering a sunflower crop with a slight wind blowing into my back. A female Cinereous harrier was gliding against the wind just above the sunflower heads and was looking at something on the ground. It was so close that it allowed me to see its wing feathers fluttering in the wind and its tail manouvering to keep stabilized, then it looked at me and as if annoyed it just let itself be blown some distance back to start all over again. But the trips sighting was still to come. While driving on a farm road to some fields, I saw a small bunch of about 6 Field Flickers flying about 50 metres in front of the truck that landed on some fence posts calling noisily and take off again when the truck would catch up with them. This they did several times. What I did not realize until it attacked was that a Peregrine Falcon was following the truck trying to take advantage of the startled birds. The Field Flickers are large woodpeckers and when the Peregrine Falcon was close enough they would sit on the nearest fence posts hiding yet oppose to its extended feet with open claws their long sharp bills causing the falcon to swerve away. This happened several times to the falcons disappointment. A bit farther away a couple of Burrowing Owls were sitting on the fence posts and as we neared them they also decided to take away for a short flight. The Peregrine Falcon attacked them inmediately but in response the owls dropped on the nearest fence posts and showed the falcon their open beaks. After a second unsuccessful attack, the Peregrine Falcon decided to leave just followed by the "cackling" calls of the triumphant Field Flickers left far behind. Some more birds seen:
This year the last Fork-tailed flycatchers I have seen around Buenos Aires (Costanera Sur NR) were on February 15th. I was surprised to see a lonely mature bird in the southwestern Santa Fe area but it surely was finding still enough food in the warm weather before moving farther to the north. Most of the tyrants seen were lonely birds although feeding actively. Swallows were mostly seen in the afternoons flying above the crops and also high in the sky. While in the Balcarce Hills, I managed to see 2 Bar-winged Cinclodes that came flying fast and dropped into some tall weeds. They gave me quite a good chance to look at them from a close distance before flying away.
As is quite common by this time of the year, many birds bunch up into huge flocks. This was the case of the Grassland Yellowfinches and Brown and Yellow Marshbirds. Saffron Finches as well as siskins make quite smaller flocks but still keep bunched together until spring time. The singing of the males in these species is almost something unheard by this time yet the Chalk-browed Mockingbirds start singing as well as some lonely Red-crested Cardinals do. Total bird species seen: 88. Not so bad after all!