Homeland – Nature of Alonissos

Having been born and raised on a small Aegean island, it was only natural that I would develop a fondness of insular ecosystems during my growth as a naturalist. Indeed, islands, especially the Mediterranean ones, hold a special place in my heart.

One particular island stands out. My homeland, Alonissos, is one of the lesser known Greek islands - also known as 'Ikos' (in Ancient Greece) and 'Liadromia' (up until the 19th century), it is the third largest island in the Northern Sporades archipelago. It belongs to the prefecture of Magnesia, is 4,5 km wide at its widest and 20 km at its longest and covers a total area of 64,5 square kilometers. It has a population of approximately 2,700 inhabitants and has four main settlements: Patitiri, Votsi, Steni Vala and Chora. The island has a rich biodiversity, hosting several endemic and endangered species. The island has received priority conservation measures over the last 30 years, following the establishment of a marine protected area - The National Marine Park of Alonissos, which was founded by Presidential Decree on 16th May, 1992 and is the largest marine park in Europe.

View from Kalovoulos hill

It was in this biodiversity hotspot where I made my first steps into the world of naturalism when I was no older than 5 or 6 years old. Although this was first sparked by paleontology, it was quickly followed by entomology and all things fauna-related. Either unearthing what I used to call 'dinosaur bones' (but were actually odd looking sticks), catching and identifying insects in the fields outside my home or fishing at the nearby harbor, my passion for all creatures grew larger with time. Eventually, when I was in my teens, I bought a compact camera and dived deeper into this incredible world, setting a goal to document as much of the island's biodiversity as I could. Although my research interest has, over the years, shifted towards vertebrates (especially reptiles & amphibians), my field time in the wilderness of this island helped me gain a ton of knowledge on both flora and fauna, and built the foundation of the naturalist I am now.

Anyway, buying that first camera led to me collecting a massive amount of pictures of wildlife from Alonissos, which I will be presenting below through a short guide to the island's wildlife.

Chapter 1: Introduction to Alonissos

Although the island's vegetation is quite similar to the rest of the Sporades, it gradually becomes more sparse and xeric towards the eastern end of the island. It offers a wide variety of vegetation zones, comprising of shrublands, forests, meadows and groves of different species composition. Human intervention (agriculture, livestock grazing, etc) is somewhat ubiquitous through the island, with endless olive groves and to a lesser degree, vineyards and pastures. In general, the SW end of Alonissos, (especially the lowlands) has more productive soil and is covered by cultivated land, aleppo pine forests, azonal stream vegetation and has more humidity-loving vascular plants, like ferns. The NE part, on the other hand, is an unhospitable, rocky and barren place, with limited productive plains and agricultural land. It is covered by tall maquis, phrygana and woodland formed by evergreen sclerophyllous trees, like holm oak and Cretan maple. The central part is an intermediate phase.

When it comes to geology, the island is dominated by limestone throughout its whole extent, with upper quaternary lake deposits at the SW part. It is of generally hilly landscape and has a relatively low elevation, reaching about 475 m asl at Kouvouli Mt. Other significant peaks are Geladias (449 m), Xiropefko (400 m), Serafeim (388 m), Galanou Rachi (346 m), Tourkovigla (340 m), Frouros (331 m), Kalovoulos (325 m), Vouno (260 m) and Strovili (255 m), which together with the hills of Skopelos form a perpetual mountain range. Apart from hills, the geomorphology of the island is also comprised by gorges, steep cliffs ending abruptly into the sea, caves, bays, small capes, valleys, ravines and lowlands. Numerous offshore rocky islets also surround the island, such as Manolas off the northern coast and Kokkinonisi off the southern coast.

Standing or flowing water is somewhat scarce on Alonissos. Only one natural wetland occurs, the Agios Dimitrios lagoon, which is a seasonal, coastal marshland located at the NE part of the island. Few streams, which are strictly seasonal, also flow in a handful of locations. In the early 2010's, a freshwater dam was also constructed in the valley of Kastanorema, which, for technical reasons, was never operated. Climate-wise, January is the most wet month (average monthly precipitation is 149,9mm), while July is the driest (average monthly precipitation is 21,1mm). July is also the warmest month, with an average maximum temperature of 31°C, while January is also the coldest, with an average maximum daytime temperature of 11°C. The average annual temperature on Alonissos is 17°C with average annual humidity at 67%.

Due to the small population, the effects of human presence on the terrestrial environment of Alonissos are currently limited, despite the fact that tourism is the island's main source of income. Other industries include agriculture, livestock farming, offshore fishing and beekeeping.

Patitiri harbor

Steni Vala village

Typical sight at Chora

Sheep at Isomata

The northern coast

Fishing boat near Mourtias

View from Serafeim hill towards Kouvouli and the plain of Gerakas

View from Koumarorahi hill towards Agios Dimitrios lagoon and Peristera

View from the top of Kalovoulos, Manolas islet can be seen

Manolas and the smaller Stavros islet

Pine forests dominate the SW part of the island

Gorge of Kastanorema as seen from the nearby hills

Typical agricultural land

View towards Peristera

The Agios Dimitrios lagoon

Old farmhouse on Alonissos

Agricultural area at the SW part

Picturesque beaches are what the island's mostly known for

Chapter 2: Flora

As mentioned above, the island has very diverse flora, ranging from endemic chasmophytes, to orchids, to grasses, to shrubs and to different tree species. The main vegetation types are as follows:

Pine forests: They consist of Aleppo Pine (Pinus halepensis), occupying large areas at the south-western and central parts of the island. Pine forests occur from sea level to approximately 350 m asl. They begin as particularly dense at the westernmost parts, slowly fading at the central part of the island, before being replaced by other habitat types. The bottom layer of pine forests is very often covered by grasses, maquis or ferns.

Oak forests: Woodland formed by Holm Oak (Quercus ilex) dominate the higher elevations of central and north-eastern Alonissos. They are usually closed, low canopy forests, often bordered by open shrublands. They are present from sea level to 450 m asl, although they are mostly typical of altitudes above 300 m asl. Their lower layers are usually under heavy grazing by goats. Other trees are commonly present as single stands within holm oak forests, such as Terebinth (Pistacia terebinthus) and Cretan Maple (Acer sempervirens).

Thermo-mediterranean maquis: Perhaps the most common vegetation type present throughout the island. Thermoxeric maquis is composed by a large list of evergreen shrub species, with the most typical examples being Mastic Trees (Pistacia lentiscus), Kermes Oak (Quercus coccifera), Strawberry Trees (Arbutus spp.), Carob Trees (Ceratonia siliqua), Olive Trees (Olea europaea), Common Myrtle (Myrtus communis), Green Olive Trees (Phillyrea latifolia), Phoenicean Juniper (Juniperus phoenicea), Heath (Erica spp.), Bay Trees (Laurus nobilis), Weaver's broom (Spartium junceum), Spiny Broom (Callicotome villosa), and others. Dense maquis covers most of the island's surface, from sea level to approximately 450 m asl.

Phrygana: Phrygana are characterized by low thermoxeric shrublands consisting of thorny shrubs and other low flowering plants. Although they occur throughout the whole island, they are mainly typical of the more arid areas, such as rocky shores, beaches, hillsides, small offshore islets, as well as the higher elevations (above 450 m asl.). The most characteristic species composing phrygana are Thorny Bournets (Sarcopoterium spinosum), Spiny Spurges (Euphorbia acanthothamnos), Jerusalem Sage (Phlomis fruticosa), Conehead Thyme (Thymus capitatus), Greek Sage (Salvia fruticosa), Rock Rose (Cistus spp.) and several others.

Azonal vegetation: Hydrophilic plants form dense riparian vegetation around water sources, especially intermittent streams and river beds. These zones are often found within cultivated areas, pine forests or maquis and are characterized by plants like Giant Reed (Arundo donax), Ferns and dense shrublands of species like Brambles (Rubus sanctus). In addition, meditteranean salt meadows formed by wetland species such as Sand Dropseed (Sporolobus pungens) and Rushes (Juncus spp.) exist at the seasonal lagoon of Agios Dimitrios.

The island also has a selection of notable flowering plants, such as Sporades endemics (e.g. the Skopelos bellflower, Campanula scopelia) and dozens of orchid species.

Juda's tree (Cercis siliquastrum)

Greek strawberry tree (Arbutus andrachne)

Juniper (Juniperus turbinata)

Pink rock-rose (Cistus creticus)

Cretan maple (Acer sempervirens)

Violet bird's-nest orchid (Limodorum abortivum)

Balkan anemone (Anemone apennina subsp. blanda)

Skopelos bellflower (Campanula scopelia)

Four-spotted orchid (Orchis quadripunctata)

Bug orchid (Anacamptis coriophora fragrans)

Sage-leaved rock-rose (Cistus salviifolius)

Common poppies (Papaver rhoeas)

Chapter 3: Fauna (vertebrates)

Due to the area being a marine protected park, much is known about the aquatic vertebrates in the waters surrounding Alonissos; about 300 species of fish, 6 species of cetaceans and the Mediterranean monk seal (Monachus monachus) can be enountered within the marine protected area.

Terrestrial vertebrates are not so well known. A grand total of 80 avifauna species had been recorded in the area until recent years, but through my own observation I was able to take this number up to 160, out of which 59 breed regularly. The majority of species are either passage migrants, summer visitors and wintering species, while 34 are year-round residents. The most common orders of breeders are Passeriformes (32 spp.), Accipitriformes & Falconiformes (7 spp.) and Strigiformes (5 spp.). Notable breeding species include Eleonora's falcon (Falco eleonorae), Peregrine falcon (Falco peregrinus), Bonelli's eagle (Aquila fasciata), Short-toed eagle (Circaetus gallicus), Audouin's gull (Ichthyaetus audouinii), Scopoli's shearwater (Calonectris diomedea), Levantine shearwater (Puffinus yelkouan), European shag (Phalacrocorax aristotelis), European turtle-dove (Streptopelia turtur), Eastern subalpine warbler (Curruca cantillans), Rueppell's Warbler (Curruca rueppelli), Blue rock-thrush (Monticola solitarius) and Long-eared owl (Asio otus).

Wood sandpiper (Tringa glareola)

Northern wheatear (Oenanthe oenanthe)

Audouin's gulls (Ichthyaetus audouinii)

Eleonora's falcon (Falco eleonorae)

European robin (Erithacus rubecula)

Bee-eater (Merops apiaster)

Black-spotted redshank (Tringa erythropus)

Lesser gray shrike (Lanius minor)

Reptiles are comprised by a total of 10 species. Those are Caspian whip snake (Dolichophis caspius), Cat snake (Telescopus fallax), Leopard snake (Zamenis situla), Nose-horned viper (Vipera ammodytes), Balkan green lizard (Lacerta trilineata), Erhard's wall lizard (Podarcis erhardii), Kotschy's gecko (Mediodactylus kotschyi), House gecko (Hemidatylus turcicus), Snake-eyed skink (Ablepharus kitaibelii) and Marginated tortoise (Testudo marginata). In addition, Marsh frogs (Pelophylax ridibundus) existed historically, but are now extinct. There are not a lot of terrestrial mammals - the list consists of Wood mouse (Apodemus sylvaticus), Rock mouse (Apodemus mystacinus), House mouse (Mus musculus), Black rat (Rattus rattus), Brown rat (Rattus norvegicus), Edible dormouse (Glis glis), Northern white-breasted hedgehog (Erinaceus roumanicus), Wild rabbit (Oryctolagus cuniculus) and reportedly Beech marten (Martes foina), which I have never personally seen on the island. In addition, a handful of chiroptera (bat) species occur, such as Common pipistrelle (Pipistrellus pipistrellus), Greater horseshoe bat (Rhinolophus ferrumequinum) and European free-tailed bat (Tadarida teniotis), though more species are likely present.

Nose-horned viper (Vipera ammodytes)

Erhard's wall lizards (Podarcis erhardii ruthveni)

Balkan green lizard (Lacerta trilineata)

Caspian whip snake (Dolichophis caspius)

Cat snake (Telescopus fallax)

Kotschy's gecko (Mediodactylus kotschyi)

Northern white-breasted hedgehog (Erinaceus roumanicus)

Chapter 5: Fauna (invertebrates)

The invertebrates are likely the least studied group of biodiversity on Alonissos. Almost no literature reports exist, despite the vast diversity of taxa on the island.

Although my knowledge on this group of animals is limited, during my fieldwork on the island I was able to photograph a few hundreds of species, primarily insects, many of which have remained unidentified. Below is a fraction of that collection.