Dialogues between a botanist and an ornithologist

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The book “Dialoghi tra un botanico e un ornitologo” (Dialogues between a botanist and an ornithologist) is written by Angelo Meschini and Carlo Mascioli in the form of a dialogue. The two authors question each other on the relationship between plants and birds, on ecology and ethology, describing the different types of habitats that can be found in the Maremma, with particular reference to Latium and lower Tuscany. The dialogue is not only a literary pretext, but the book is inspired by real conversations that the two authors have been having together for about thirty years during outings in nature. Thus, as the conversations flow, 172 species of plants, 165 of animals and 9 of mushrooms are described, treated in an ecological key, with reference to the Mediterranean environment, from the coasts to the hinterland, from the most natural environments to urban centres.

The first part of the book is mainly devoted to tree and forest ecosystems, and the conversation follows a common thread represented by two fundamental reference points: habitat functionality and landscape.

“A white feather descended slowly and you could look at it in filigree. The whiteness contrasted with the emerald green of the Aleppo pines Pinus halepensis and the slightly lighter domestic pines Pinus pinea. The Mediterranean coastal pine forests are home to what are known as ‘garzaie’ (heronry) in a very discontinuous manner. These form marvellous assemblages of nesting herons, with their hoarse voices, fluttering feathers and discreetly “strong” odour, to put it mildly. Our polyspecific heronry was home to Bubulcus ibis egrets and Egretta garzetta. The nests were placed almost entirely on Aleppo pines, probably because of the “narrower” conformation of the globes that build the foliage. Science rewards them with immense joys: the crests of the young “guardabuoi” that intertwined in mock juvenile struggles, the very white “aigrettes” of the adult egrets that moved in the wind like an expanse of stipe in a Pannonian steppe, the ecstasy of those moments out of time in an archaic and marvellous gynaecium just a few hundred metres from scattered unauthorised buildings and the din of motors”.

Certainly the stone pine owes its enormous success not only to its resin, but also to its seeds, the pine kernels, which were already appreciated in Roman times and still are today. It has been admired since ancient times for its unique appearance and is still one of the most common ornamental trees in central Italy, a real symbol. Unfortunately, in recent decades we have witnessed a reversal in tastes and fashions: the stone pine, planted along streets, in squares, gardens and courtyards, has become a victim of persecution. We don’t like it any more, it often has intrusive roots on our road surfaces, and lately it has also been causing us great fear because of the frequent collapses that occur, with exaggeratedly alarmist tones reported in the newspapers (“killer pines”).

This is why the unfortunate pines are being harassed by throngs of self-styled tree pruners, disgruntled citizens and administrators when they are not immediately felled: Without any knowledge of how trees work, starting with the fundamental role of chlorophyll photosynthesis, and without any knowledge of modern arboriculture, they are attempting to lighten the weight of their foliage by removing a large part of it, in the belief that this will reduce a so-called ‘sail effect’ and facilitate the passage of wind, but in fact distorting their aerodynamic structure; they are attempting to change their peculiar shape by cutting off large branches.

Thus our beautiful pines have now become strange and sinister trees, unnaturally slender, very tall, reaching heights they would never attain spontaneously, particularly fragile long levers, grotesque and slouching giants that look less and less like the stocky, short, stocky tree with its flat, expansive foliage that would be the domesticated tree without our hand, as we can still admire it along the Aurelia, next to the red cantoniere houses”.

In addition to “natural” and forest ecosystems, a wide-ranging treatment is devoted to agricultural areas, particularly fragile environments described from an agro-ecological perspective.

“At present, olive groves cover huge areas where once there were Mediterranean woods (holm oak, scrub) and more mesophyll woods (oak): this is not only of landscape importance – how could we do without the silver brushstrokes of the Olea europaea olive tree on the mosaic of greenery that is the rural and forest fabric of our territories? – but also of considerable ecological importance. In place of the forests that once were, there are now not just simple herbaceous cultivations, but olive groves, i.e. relatively complex agro-systems that can be compared, in some respects, to forests: soil protection, the presence of a diverse range of soil micro-organisms, food supply for numerous animals, nesting opportunities even for species typical of mature coenosis, are factors that characterise olive groves as the most structured and rich agrarian ecosystems. Obviously, the more we move away from organic farming and towards intensive farming, the more we impoverish the olive grove agro-system and the more harmful effects we have on the environment.

“These artificial habitats are home to some very interesting fauna. A parallel can be drawn between the olive tree and a small passerine bird, the Sardinian warbler Sylvia melanocephala. Both are circum-Mediterranean species, their ranges overlapping, representing two emblems of the Mediterranean. Another nesting bird typical of olive groves, for which the olive tree is probably the most frequently used site, is the common creepers, Certhia brachydactyla, a tiny passerine bird that uses the cracks in old olive trees to lay its eggs in the twisted gynoecium. It is amusing to compare it in this respect to the nuthatch Sitta europaea, which does the same thing but descends the bark, as if there were a sort of alternating one-way street in the trunks.

Thus, passing through stony meadows and steppe environments, field hedges and tree lines, marsh and river environments, dealing without prejudice with controversial concepts such as allochthonous species or so-called weeds, the book ends with the urban ecosystem, rich in unexpected biodiversity and complexity. This is a synthesis of different landscapes, frequently overlapping, in which residual spontaneous flora that existed before the city, or that escaped from cultivation, is accompanied by that used by man to create parks, gardens and street trees.

“Let me make a rather daring comparison, looking back at what we have said so far about rural and natural environments and imagining that we are looking down on a city from above: the asphalted and concreted surfaces, due to the scarcity of animal life, are comparable to simplified and intensively cultivated agricultural areas (cereals, vegetables, hazelnuts), where fauna has no chance of survival due to pesticides and processing. The ruderal flora on walls and pavements, as well as on balconies, provide animals with shelter and trophic resources just like field hedges and isolated trees; parks and gardens are comparable to residual forests that break up the monotony of arable land and pasture; street trees behave like riparian formations, with the very important function of ecological corridors.

The urban environment is characterised by its particular microclimate, which can be summed up as a “heat island”, and by the prevalence of stone substrates: these two factors determine a high “degree of Mediterranean character” even in the cities furthest from the sea, allowing life to xerophytic and thermophilic plants such as the caper Capparis spinosa and birds native to the cliffs overlooking the sea, such as the domestic pigeon Columba livia var. domestica, species that are defined as synanthropic because of their predilection for man-made environments.

“For us humans, there is a clear difference between urban and natural environments, whereas, it has to be said straight away, birds have another point of view: their life is really three-dimensional and they look at the world from above. It may seem surprising, but a large building, perhaps a skyscraper, is not so different from a sea cliff or a tufa wall in the eyes of a bird; a series of contiguous gardens is not so different from a natural mosaic environment. A series of adjoining gardens is not so dissimilar to a natural mosaic environment. Cities are also a popular ecosystem for birds because of two other factors: the average temperatures are higher than in mountains, plains and valleys, and hunting is not practised in cities”.