E ste Saturday I had the pleasure to participate again in the "Green Future" by Miguel del Pino, who now manages broadcast on Radio.
Incidentally, among the "gadgets" that is to the right of this text I have added a link to the page where you can download and listen to these programs. On this Saturday is set HERE.
Chick house sparrow, Passer domesticus ,
leaning out a nest box in my garden
Well, during and after the show I talked to Miguel about the alarming decline in the number of sparrows in our cities. There have been many possible reasons, perhaps none quite explain why the process, but all together contribute to it. In other European cities has spoken of massive infections, although, as Miguel said, sparrows are not sick. It is also possible that urban sanitation contribute to reduced food availability, although this has not been inconvenient for other birds to come into the cities and become increasingly abundant.
Macho sparrow, Passer domesticus, in a string of peanuts in my garden.
Another possibility is competition with these other birds, including direct predation of nests by the Magpies, for example, or the destruction of these by parrots and starlings.
domestic pigeon, Columba livia , in the Retiro park in Madrid. But I am afraid that you are playing an important role in feed contraceptives are used in some cities in the fight against domestic pigeons. The sparrows have easy access to food that they can be put to pigeons, I would even say that they will eat most of the feed. We do not know for sure where and when in use, but these products are very difficult to control once placed in the environment. I hate to kill any animal, but I'm more afraid to release chemicals that potential.
Group pigeons, Columba palumbus Alpedrete in a neighborhood of Madrid.
Curiously, years ago, the bird watchers who put nest boxes and feeders in parks and gardens, considered undesirable elements sparrows by competition with species more "noble." I am now happy pudiéndoles offer both.
Tórtolas Turkish Setreptopelia decaocto, on a street in Alpedrete
Other birds of the family of pigeons, such as pigeons and doves are, however, each more abundant. The pigeons are leaving to migrate and are no longer attractive to hunters waiting in the "pigeon steps" to shoot comfortably seated from his hiding place, the band that tries to overcome the mountain by some valleys. It has made a selection the most direct: migrating dove dies, pigeon remains in the city survives.
Perhaps these two species of Columbidae, which nest and roost in trees but no buildings, have more future in our cities that domestic pigeons are being persecuted for damage caused to buildings and monuments. Also, some suspicion still have not come so easily to the food offered.
Blackbird, Turdus merula in my garden.
The collared doves are occupying both urban gardens as the field in a stunning natural expansion that may displace the common turtle. It is a species much more aggressive in defending their territory. In this case, the competition itself is evident.
Urraca. Pica pica, in my garden
has also been impressive expansion of magpies, both in the field and in the city.
Among the few positive factors of the sparrows, and all wildlife in general, is environmental education in recent years. I still remember when almost every kid had a real obsession stones for hunting birds with slingshots or, if he could afford, with air gun. Fortunately that has changed little since they come up now. And in the same case are the squirrels, which are gradually populating reoccupying voids and new parks and gardens in residential areas. When I was a kid the squirrel appeared in a collection of matchbooks as small game. " Something we are civilized.
Urraca harassing a squirrel in the park of El Retiro de Madrid
Starlings, blackbirds, robins, chickadees and other tits, wagtails, kestrels and hawks show themselves increasingly large cities. However, the purely insectivorous swifts and martins, and become more limited by lack of food.
Starling, Sturnus unicolor , in my garden.
And among the most exotic species are two increasingly abundant parrots, parakeets and Kramer Argentina. While in Madrid and its surroundings believe that only the first of them breeding in other cities in warmer climates are those of Kramer, budgerigars and inseparable, as well as weavers, nightingales of Japan and some other species more, all for no natural expansion, but by the release or escape cage birds.
parrot Young Argentina, Myiopsita monachus, at Casa de Campo, Madrid, feeding on gálbulas of yours.
urban aquatic species.
'm old enough to remember when Madrid was the gulls. I have lived more than 30 years in an apartment near the Manzanares River and the first year came the black-headed gulls was for me an event. I remember drawing and notes in a notebook at home looking after shaking hands in the bird guide to be sure. I saw them arrive in mid-October. I can not say when they left, but the days before and looked away some copies to the head black. Over the years I have witnessed the arrival also of some clueless Gull, whose number was increasing every year, and finally, the yellow-legged river that are not nothing, but have also been added to this internal migration. The final change has been much more recent, some gulls are even in summer. The food available in landfills has a lot to do with it, as for not migrating storks.
laughing gull, Larus ridibundus , In the Santillana reservoir, Manzanares el Real, where they go to sleep after feeding in dumps Colmenar Viejo, Madrid.
Cormorants seen in Madrid, however, have more to do with better preservation of the Manzanares River, which has fish to offer. I've said several times, the best place for cormorants in the capital is on the lampposts and bridges that are near the exit of the tunnels in the M-30 to Andalusia Road. **************
I also want to note that some of the new "gadgets" offers science news that I have called attention recently. It is noteworthy that of the polar bear hybrids, tangible evidence of climate change. And the Arizona and pollution, which claimed to have spoken this week, but I have not done so because of bad weather has prevented me from taking pictures I wanted.
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