The ANUU Migratoristi takes stock of the situation of the migratory pass in the first quarter of the year between African winds and Atlantic anticyclones.
After a month of February, which will be remembered for the great cold and the snow that covered the whole peninsula with an event not seen since 1956, it was thought that the beginning of spring was more pleasant.
Temperatures have been below freezing for as many days as they were over half a century ago. An anomaly for a phenomenon that repeats itself every 20-30 years and always with the same dynamics. Swirling winds from the east, abundant snow even in the plains and frost. This phenomenon manifested itself in 1929, 1956 and 1985. Only towards the middle of February did the influx of cold air from the north-east weaken, leaving Italy slowly and returning to normal.
After the great cold, spring arrives early with a climate above the seasonal averages which compensate, even in the statistics, the wave of frost. An anticyclone that previously was stationed in the middle of the Atlantic Ocean and which due to its position had favored the entry of cold air from Siberia, at this time of the year it moved towards the Mediterranean thus favoring a mass of warm air from North Africa has invaded the Italian peninsula.
This resulted in a thermal anomaly bringing temperatures above twenty degrees centigrade. A reversal of the situation. In this way, spring began with the sun bright and high in the sky, pleasant and sweet air. The month of March ends as the hottest since 1989 with temperatures above the average of 2,5 degrees thanks to the high seasonal highs.
April, on the other hand, begins with a frozen spring on Easter day, giving us an icy start to the month, almost treacherous after the illusion of a near summer. In short, until April 22 our atmosphere remains unstable, controlled by a vast depression system that embraces all of Europe.
The rains begin and not even a single sunny day suggests that it is spring. There are perturbed impulses from the southwest that spin counterclockwise around this vast depression as migration in some areas moves quickly. Trans-Saharan species begin to rise and, in suitable natural areas, can be seen very unevenly.
At the FEIN Ornithological Observatory of Arosio the first trans-Saharanians begin to be noticed on 10 April with the ringing of the first Prispolone, followed by that of a green Luì on the 16th and by the Black Balia on April 19th.
The bottacci thrushes (the first specimen in pre-nuptial migration was ringed on 23 April), passed quickly throughout the territory, leaving a faint trail of individuals still in the second decade of April, many species such as Black Redstart, Luì gross, Cutrettola, Hoopoe, Rondine including the Swift, and some waders begin to be noticed with a slight delay on the whole territory apart from the few exceptions.
The ornithological stations together with the signalers scattered throughout the Italian territory speak of signs of migration that are not very exciting even if in the most congenial natural places where the practice of ringing is active, with constant and continuous effort, the presence of migrants is noted. Between delays and advances, however, in April the species are passing or arriving to reach the nesting sites.
However, it should be considered that as far as the FEIN Ornithological Observatory of Arosio is concerned, the first quarter of the year was not at all negative, so much so that 139 subjects were analyzed and ringed for 13 different species on an annual average for the last five years of 132 subjects analyzed for 16 species.
A good start if we consider that this first quarter ranks third in the last five years behind 2008 with 217 subjects analyzed for 21 species and 2009 with 160 subjects belonging to 13 species. Although the temperatures of recent days, before the anniversary of 25 April, are still low and the rains are the masters, it is hoped that the migrants have better luck and can arrive in their nesting areas to give life to the new generations, future of all kinds.
ANUU Migrators