The Mirage Of Bird Migration

Head of Romanian Ornithological Center

Over hundreds of thousands of years, Nature has searched for and found the most efficient adaptation mechanisms for each species, as well as for ways in which groups of animals and plants could support the big natural systems. In their fight for survival, some of these species found miraculous solutions, which required spending a large amount of energy and, in essence, regarded the preservation of the place they had gained in time. Flight was undoubtedly one of the most significant discoveries made by Nature. During the reign of the dinosaurs, one small lizard fancied it had found the best solution to defend itself against predators, by climbing arborescent ferns; thus this tiny creature became the first vertebrate to glance at the horizon. The Maker "cursed" these beings to be the only ones able to look at the surrounding world from up above. I call it a curse because the wish to reach the horizon must have remained a perpetual mirage for birds. Most animals are migratory, traveling over longer or shorter temporal or spatial distances, but for none of the large groups of animals (be they fish, reptiles or mammals) is this phenomenon more complex or, in other words, more representative than it is for birds. Flight itself, particularly the annual departure and return of birds, determined humans to deify them, migratory birds becoming prominent sacred symbols. From the pre-Christian era up to present time, when the phenomenon of migration is seriously studied by science, people have considered migratory birds messengers of the skies, sent by God. In Ancient Egypt, for instance, the peregrine falcon was viewed as the supreme symbol and was included in the religious pantheon. Legend has it that Horus, the hawk god, challenged Seth, the god of evil and confusion in Upper Egypt, who had murdered Osiris, Horus's father. Horus avenged his father's death and became the god of order and justice. This was the reason why the Pharaoh was seen as the earthly Horus, the master of the two lands, Upper and Lower Egypt. This bird-god possessed the attributes of illumination and peace with which he renewed the flow of life in things gone dry.Ever since antiquity, humans have used this characteristic of bird behavior. Thus, documents mention the fact that, during the Punic Wars, the Romans tied to the legs of swallows letters containing information on the situation of their Carthaginian enemies.People continued to wonder about birds disappearing at the beginning of autumn and returning in spring. The abbot of a monastery in Germany attached to the leg of a swallow hatching nearby a note which read, "Oh, swallow, tell me where you live in winter!" Fortunately, he received a reply courtesy from the aforementioned bird. The reply note read, "In Asia, in the house of Petrus." During the Middle Ages, due to an extensive practice of falconry, knowledge on the life of birds was augmented. Falcon owners would set rings or medallions on the feet of their birds, on which they mentioned the owner's name. Some of the birds were subsequently recaptured in other regions, but it was impossible to establish where they had come from unless their owner was a famous person. Thus a peregrine falcon belonging to the French king Henry IV flew over a distance of 2000 km, from Fontainebleau to the island of Malta, where it was captured after 24 hours. Another surprising event regards the 18th-century German ornithologist J. L. Frisch, who rejected the theory according to which in winter swallows sank into the mud at the bottom of rivers, re-emerging in spring to resume their existence (as the legend went), and colored the feathers of some of the adult birds, which, upon coming back to their nests in spring, had retained this color. The discovery made by the German scientist showed that swallows did not spend the winter under water, but migrated to other geographical areas. Towards the end of the 19th century and the beginning of the 20th, scientists began to purposefully ring birds in order to be able to find them again and solve the mystery of their biology, ecology and ethology. In Europe, between 1891 and 1901, Lord William Percy ringed birds, mentioning the year of the ringing and writing the letter "N" on the rings he used. To his great happiness, 58 of the 375 ringed birds were recaptured on time. During the same period, around 1890, the Danish scientist H. C. Mortensen ringed birds and engraved on the rings the address where the birds had come from, as well as a number corresponding to a file of the ringed bird, which contained facts such as: the place of ringing, the age and biometrical data of the bird, etc. This marked the beginning of scientific ringing and of a plethora of institutions being set up, which contributed, alongside famous individual scientists, to important discoveries concerning, as I have mentioned, the biology, ecology and behavior of large bird populations and, more recently, their monitoring. The ringing method initiated by Mortensen spread rapidly across Europe and ringing centers were set up by museums and universities. As examples, we could mention the Ringing Centre belonging to the Zoological Museum in Copenhagen, those set up by the Museum of Natural Science in Brussels or by the University of Aberdeen. In 1924, Sempach Ornithological Station was established, followed, in 1933, by The British Trust for Ornithology (B.T.O). Ringing stations were also set up, for instance the one on the island of Helgoland or the famous Rossitten Ornithological Station in Germany, or Station biologique de la Tour du Valat in Camargue, France. The Romanian Ornithological Center (ROC), established in 1939, was one of the first ringing centers established worldwide. It was opened by the Academy of Agricultural and Forestry Studies, under the patronage of the Ministry of Agriculture, Forestry and Royal Estate. At present, ROC successfully continues its activity all over the territory of Romania and of course, and I would say, especially, in the Danube Delta, a real cornucopia for Romanian and foreign ringers alike, as well as for professional and amateur birdwatchers. The Danube Delta is deservedly famed for possessing the vastest stretch of reed plains in the world, to which we could add its status as one of the most important wetlands on Earth and its privileged position, together with the Amazonian region, as one of the richest in bio-diversity. It is also situated on the most important migratory route in Europe. I affirm this because the Eastern European route passes through the Danube Delta, a territory which offers numerous nesting, resting and feeding places to over 350 bird species, most of which being unanimously considered as rare, living in limited habitats or on the verge of extinction. These facts have echoed with bird-lovers across the world and consequently, the Danube Delta is visited by many a birdwatcher, but, most importantly, ROC has organized and still organizes international ringing camps which yield valuable results in the fields of bird dynamics, ecology and behavior. At the moment, there are two ringing camps in the Danube Delta. One of them is located on Grindul Lupilor (Wolves' sandbank) and benefits from the contribution of English ringers, and the other is in Sfîntu Gheorghe and is part of a program initiated by ROC, Nos Oiseaux and Sempach Bird Ringing Center in Switzerland. Mention should be made of the camp's receiving ornithologists from all over Europe, in a project which is likely to last more than 3 years. ROC collects in excess of ten thousand ringing reports, which are subsequently processed and forwarded to EURING, the European body which coordinates the most significant European and global projects concerning the migration of birds ringed with metal and colored rings, in view of monitoring chiefly endangered species and protecting them worldwide. Moreover, EURING also includes the Central Data Base in Heteren, the Netherlands, whose mission is to centralize ringing and recovery reports sent by all European ringing centers, global information which will subsequently become available to all national centers, allowing studies regarding the dynamics of bird populations and not only. Therefore, we consider that, apart from licensed ringers in Romania, hunters also, due to their specialized activity, come in direct contact with birds which are interesting from a huntsman's point of view, ringed ones included, even if unfortunately (may true hunters forgive me) some of them choose to shoot down species listed as endangered. As I have already mentioned, any item of information concerning bird rings brings us closer to understanding the miraculous phenomenon of migration, a case which is yet far from being closed and which makes research even more exciting. We kindly ask that you should inform us directly of any ring that you or your friends might find, writing to the following address: Romanian Ornithological Center, 8 Ion Ionescu dela Brad Blvd, sector 1, Bucharest, Romania.

by Mircea Gogu-Bogdan