The Onion Weed

Onion Weed - Asphodelus fistulosus 

The onion weed is a spring-flowering plant of the lily family. It is found in Mediterranean countries but has been introduced in many areas with a Mediterranean climate particularly in California, Arizona, New Mexico, Texas and Mexico. It has also been introduced in Australia and New Zealand.

In the Maltese islands it is a rare species that can be found only in a few localities. I have seen in growing mostly on the walls of the bastions at the Argotti Batonic Gardens in Floriana and at Sa Maison Garden in Pieta’.

In Maltese it is known as berwieq żgħir.

In non-Mediterranean countries it has become a pest and measures are taken to try to eliminate it. This is a common situation where plants are introduced in areas where they are not indigenous. In Malta this has occurred with many species the best known being the Cape sorrel which in Maltese is known as the ħaxixa ngliża.

The onion weed is an asphodel. It is related to the very common species known as the branched asphodel. Both plants are very similar except for a big difference in size. The branch asphodel can grow up to 150 cm while the onion weed rarely reaches a height of fifty centimetres.  

This plant is an annual or short-lived perennial. It reproduces by seed which can be dispersed by wing water, machinery or agricultural produce. The seeds can also be carried around by mud attached to animals and vehicles.

The very common and larger branch asphodel flowers in winter and early spring. It grows in most habitats but is more common in rocky steppe. In some places, especially in areas that are regularly burnt, it can become the most common flowering plant.

This article was published in the Times of Malta on 23 April 2015, 

The tadpole shrimp

Tadpole shrimp - Triops cancriformis 

Tadpole shrimps are small crustaceans that were already alive 300 million years ago. They are living fossils that have outlived the trilobites, dinosaurs and mammoths and millions of other species.

They live in ponds and pools, an unstable habitat because they often dry up during parts of the year.

The tadpole shrimp found in the Maltese islands, which goes by the scientific name of Triops cancriformis, has existed unchanged for the past 200 million years or so. It is the oldest living species known.

Triops cancriformis is found in Europe, the Middle East and Japan. In many parts of Europe it has lost its habitat and has decreased considerably. In some areas it is endangered and strictly protected. Only two populations are known in the UK.

The tadpole shrimps I have seen in the Maltese islands have been about six centimetres in length although it is not unknown for members of this species to grow up to eleven centimetres long.

In Malta it has become very rare mainly because of destruction of its habitat. Many of the sites in which it used to be found have disappeared and it has also disappeared from most of its old but still existing sites.

Like the frog which shares the pools in which it lives, the tadpole shrimp has a very fast life cycle. It becomes a mature adult within two or three weeks of hatching. This allows it to complete its life cycle before the rain pools in which they live dry up.

The eggs are very resistant to drought and extreme temperatures and can survive for many years in the dried mud or dust at the bottom of a pool waiting for the right hatching conditions. They can even survive digestive juices and can pass through the digestive system of a bird unharmed. It is probably the ability of the eggs to survive under very difficult conditions that has enables the various species of triops to survive for so many millions of years.

Tadpole shrimps feed on small invertebrates, microscopic particles and plants. They absorb oxygen through their legs and can be seen moving their legs rhythmically all the time to move the water around them. They usually swim with their shield upwards but when oxygen is scarce they swim upside down with their feet close to the surface of the water where there is usually more oxygen.

The name Triops is derived from two Greek words meaning three and eyes. It got its name because these species have a pair of compound eyes and a third eye known as the ‘naupliar eye’ in between. 

This article was published in The Times of Malta on 3 April 2014.

Birdwatching in Buskett

Last Monday bird watchers at Buskett saw and photographed two black storks by soaring over Buskett and other parts of Malta. The two spectacular birds were flying at a great height and visited Buskett several times during the afternoon. As it was getting dark they began to loose height and attempted to land somewhere outside the limits of the bird sanctuary but as they were landing several shots were heard. One of the two birds was seen falling to the ground shot. The other did not rise and was presumably shot as well.

When I started watching birds in 1977 visiting Buskett Gardens in September was like finding yourself in a war zone during a fierce battle. There used to be hundreds of hunters openly walking around as if they owned the place shooting at any bird within range of their guns. Buskett was a no go area for all non-hunters as it was too dangerous for anybody to be in the garden and in the surrounding countryside.

Birdwatchers used to try to be as innocuous as possible as their mere presence was taken as a provocation by the hunters some of whom did not think twice before shooting in their direction. The police hardly ever turned up at Buskett and when they did, not much action could be taken. The law stated that it was illegal to discharge a firearm in Buskett Gardens but it was not illegal for anybody to be there with a gun in his hand waiting for a bird to come within range. Furthermore birds of prey were not protected species.

The legislation changed in 1980. Birds of prey were among the birds which could not be shot but most hunters ignored the law and continued to shoot at raptors as before. Hundreds of honey buzzards, marsh harriers, kestrels, hobbies and other rare birds continued to be shot in Buskett.  In view of this situation youth members of the BirdLife Malta which at the time was known as the Malta Ornithological Society organised protests against the annual massacre of birds of prey in Buskett. 

During these protests they were often attacked and sometimes injured. After years of campaigns the situation started to change. Today Buskett Gardens is a relatively safe place for birds and humans. One can watch migrating birds without seeing them being shot in the bird sanctuary. The former youths who organised and took part in the protests in the 1980s now visit Buskett with their young and not so young children knowing that it is no longer dangerous to be there while birds of prey are migrating. Unfortunately the situation still has not changed in other parts of the Maltese islands and birds of prey as well as other protected birds are still being shot. 

This weekend Maltese and foreign volunteers who are monitoring bird hunting found the remains of nearly two hundred protected birds at Miżieb which is public land managed by the hunters. Miżieb is an important spot for migrating birds where and should be declared a protected area for birds and humans. 

This article was published in The Times on 23 September 2009. 

The giant orchid – an endangered species

Giant orchid (Barlia robertiana)

The giant orchid is a rare endangered orchid that grows in a handful of localities including the garigue behind the Għadira Nature Reserve. It is a large winter-flowering species, which was discovered in Malta about twenty years ago.

The first flowers appear in December and usually disappear by February. Although it is a large orchid, local and visiting botanists had overlooked it probably because these tended to carry out fieldwork later in the season when more plants can be found and thereby missing these winter-flowering plants. At this time other orchids also start to flower including the brown orchid, which is much smaller and easily missed unless one knows what to look for.

The giant orchid is known in Maltese as orkida kbira. It is found growing in garigue, maquis, scrub, open woodland and roadsides throughout the Mediterranean. 

The few specimens found in Malta grow in open rocky areas. The specimens growing at Għadira are now threatened by a new road, which is being proposed to cut through the area. If built this road would destroy a large area of garigue, a rich habitat which has decreased because of lack of appreciation of its value and importance. 

Garigue supports a large percentage of the flora and fauna of the Maltese islands including many orchids and other rare species of plants. It is in garigue that the thyme, which provides the nectar for the Maltese honey, grows.

The new road should not be built, as it would result the destruction of another rich garigue area and the loss of more precious habitat. We have lost far too much countryside and what little is left should be protected and conserved.

This article was published in The Times on 07.01.09.

Bees make the world buzz!

For many, a bee is just the honey bee, which is just one species of more than 20,000 recorded bee species. 

Bees are closely related to wasps and ants and are important pollinators. They evolved from wasps which are predatory insects and can nowadays be found wherever insect-pollinating flowers manage to live.

Insect-pollinated flowers, before the appearance of bees, were pollinated by other insects such as beetles, flies and butterflies. The appearance of bees probably led to a greater diversity of flowering plants.

Bees became specialised nectar and pollen feeders which put them at an advantage over other insects. Nectar is the source of energy which allows these insects to fly tirelessly in search of flowers and nectars provides the proteins for the growing larvae.

More than sixty species of bee have been recorded in the Maltese islands and more are likely to be found as this group of insects has not been thoroughly. 

Some bees live in colonies while others are solitary. Bee communities may semisocial. These consist of colonies of sisters living together in which there is division of labour. 

More advanced communities are called eusocial. These are more complex organisations consisting of a queen bee, female workers and male drones.

Solitary bees do not live in colonies although in some species the individual nests are built close to each other giving the impression of a colony. The largest of the solitary bees is the large carpenter bee which is known in Maltese as bomblu iswed.

The bumble bee, known in Maltese as bomblu, is a social bee of great benefit to humans because of its pollinating activities.

A close look at indigenous flowers including species which flower during the summer months such as the pennyroyal (plejju), fennel (busbies), caper (kappar) and squirting cucumber (faqqus il-ħmir) can lead to the discovery of the interesting world of bees. 

This article was published in The Times on 13.06.2012

The moth with golden wings

Goldwing (Synthymia fixa)

Moths are common insects but being nocturnal they are often unseen and unsung. 

Most moths spend the day resting in a safe place flying off at night in search of a partner or to lay eggs on the right food-plant. During the night some species also visit flowers to obtain nectar which provides them with energy.

For safety they rely on camouflage. Most moths are grey or brown and when resting remain motionless until approached too closely. Some also have brightly coloured underwings. These are the two wings which when the moth is resting are hidden under the forewings. In some species these wings are brightly coloured being yellow, orange, red or pink. 

When the moth is resting the colourful wings are well hidden but when the moth is disturbed it flies off uncovering the hind-wings and startling approaching predator which very often is too surprised to continue with its approach. This gives the moth enough time to fly away. 

The moth usually does not fly more than a couple of metres but as soon as it lands it hides the brightly coloured hindwings and again becomes practically invisible.

One such moth is the goldwing, which is known in Maltese as baħrija tas-silla tal-mogħoż.  The silla tal-mogħoż is the pitch trefoil, a common annual plant on which this species lays its eggs and thus on which the caterpillars feed. 

The adult moths can be seen in April and May It is a small moth with a wingspan of less than 40mm. It is native in southern Europe and North Africa.

The goldwing belongs to the owlet moth family; a large family with over 42,000 species. Of these 1,4500 are found in Europe of which just over 160 are found in the Maltese islands. Some of these are agricultural pests and can damage crops. 

This article was published in The Times on 23.05.2012

Emblem of hope

The hawthorn

Hawthorns are large bushes or small trees that belong to the rose family and are native in Europe, Asia and North America. 

These trees y are an important source of food plants for birds and insects. and are often planted by naturalists to attract wildlife.

Hawthorns are at their best in spring and autumn, most pictures of these small trees show the trees in autumn when their branches are laden with small apple-like fruit. 

The fruit is beautiful to look at but its function is not to please us but to attract thrushes and other birds and entice them to eat the fruit so that they would help disperse the seeds. 

Same is true in spring. The pleasant fragrance released by the beautiful white flowers of the hawthorn attracts large numbers of insects which are important for their pollination.

The name hawthorn is now used for all species in this group of plants but it was originally used only for one species that is common throughout most of Europe including Malta.

In Maltese it is called żagħrun. This species grows wildly in the Maltese countryside but is usually noticed only in autumn.

A less common species, the Crete hawthorn, is known in Maltese as għanzalor. 

Although this species is found in other Mediterranean countries it is not known whether it is indigenous to the Maltese islands as it might have been brought and planted here for its fruit. 

Sometimes one can also meet hybrids which are known in Maltese as għanżalor bagħal.

The hawthorn was commonly used in traditional medicine and is still being studied as a source of antioxidants and other phytochemicals which can be used as a cure for a number of medical conditions including cardiac insufficiency. 

The fruit can be made into jellies, jams and syrups and to add flavour to brandy. The petals can also be used in salads.

It is inevitable that such a popular plant would have many important folk traditions surrounding it. It is the emblem of hope and in parts of Britain and Ireland it was considered unlucky to uproot it. 

This article was published in The Times on 09.05.2012

Tree mallow

Tree mallow

In Malta several species of mallow are found growing wild. They are known as ħobbejz, a word of Arabic origin meaning small loaf.

The name was presumably given to it because of the seed pods which have the shape of a loaf. A similar name is used for the seed pods in Jersey where they are known as “petit pains”.

The English name mallow comes from Old English malwe which itself comes from the Latin word malva. 

The Latin name is itself derived either from an old Greek word for yellow or from a Hebrew word which sounds like the Maltese word melħ and which like the Maltese word means salty.

In 1859 the French name for mallow, mauve, started to be used for a colour.

This plant should be instantly recognizable, yet, most people hardly notice it growing along roadsides and in abandoned fields especially close to the coast. It can grow up to two metres high with strong woody trunk which in Malta would qualify it as a small tree.

It has large leaves and from March to June unmistakable brightly coloured flowers. It grows along the coasts of Western Europe and the Mediterranean as far east as Greece. It is often very common on islands.

The tree mallow (ħobbejża tas-siġra) can grow in environments with high salinity. Like the tamarisk tree, known in Maltese as bruka, it can survive in these difficult conditions because it is able to excrete salt through glands on its leaves.

In many parts of Europe the leaves of the tree mallow were used to make poultices which were used to treat sprains and burns and in some places they are still used as animal fodder. 

They have also been used as an alternative to toilet paper.

In the Middle East the leaves are used in a traditional Arab dish known as khubeza. 

This article was published in The Times on 02.05.2012

The star of Bethlehem

Plant and animal names are a fascinating subject and can be a good topic for research and studies. 

The large star of Bethlehem, a spring-flowering plant, is a case in point.

In Maltese this flower is known as ħalib it-tajr kbir, a distinctive name for a beautiful flower but this is probably not the name country people used when referring to it. 

It is also known as ħara taċ-ċawl meaning jackdaws’ faeces. 

A hundred years ago such a name would have been considered as too rude to be used in print. 

The authors of a book on Maltese flora written in the early 20^th century left the name of this species out from their book. 

Sometime later somebody coined a new name by using its scientific name Ornithogalum and translated it into Maltese. 

Ornithogalum is made up of two Greek words ornis meaning bird and gala meaning milk  a name given to it because of its white flowers and because ‘birds’ milk’ was used by the Romans to describe wonderful things, hence ħalib it-tajr.

The white flowers of the large star of Bethlehem open on a stalk that is about thirty centimtres high which is just tall enough for the flowers to stand above the surrounding vegetation. 

It belongs to a family of bulbous plants found mostly in Europe and southern Africa. The family consists of about 150 species although not all are large and showy as this species.

Two other species, which also flower in spring, can be found in the Maltese islands. Both are much smaller.

The lesser star of Bethlehem known in Maltese as ħalib it-tajt skars was believed to be extinct but was found again less than ten years ago near Buskett. The other species, the southern star of Bethlehem, ħalib it-tajr żgħir in Maltese, is frequently found in rocky areas especially in late spring when much of the vegetation has dried up. 

This article was published in The Times on 25.04.2012

The yellow-legged wader

The wood sandpiper is a wading bird seen in the Maltese islands during migration. It is one of the smaller waders with a short fine bill and yellowish legs. 

Several species of waders visit the Maltese islands. To the uninitiated they might all look the same but with a little practice and experience identifying these birds becomes second nature.

The best place to see migrating wood sandpipers and other waders in Malta is at the Għadira Nature Reserve near Mellieħa which is open t the public on weekends but to see them breeding you would have to travel north at least as far as Scandinavia. 

The nests are built on the ground in open swampy areas in northern forests, but as the summer season so far north is very short you would have to be there between May and mid-July. 

The start and finishing dates of the breeding season depends on how far north they are. In northern Russia for example breeding does not start before June.

Some adult green sandpipers start migrating south as early as late June. 

Young birds remain behind for longer and usually leave in late August. 

This gives them time to become fully grown and to build up their fat reserves which will provide them with the energy required to fly south. 

European and many Asian wood sandpipers spend the winter in Africa. 

On their way south they stop to feed and replenish their fat in suitable places. 

Wetlands north of the Mediterranean are of great importance for these birds as the reserves they build make it possible for them to cross the Sahara desert without the need to refuel.

When stopping to feed, migrating sandpipers keep themselves busy walking continuously along the water’s edge or in shallow waters, picking up tiny aquatic insects from the mud or from the water’s surface.

Wood sandpipers have a very large breeding range and they are not considered as being endangered although climate change is seen as a threat as this could result in their specialised habitat shrinking in area.

 As the earth warms up these birds might have to travel further north to find suitable breeding sites. 

This article was published in The Times on 18.04.2012

The endemic spider orchid

The Ophrys melitensis or Maltese spider orchid (brimba sewda) is one of twenty four species of plants endemic to the Maltese islands.

It is one of a small number of insect orchids that flower in spring. This orchid has a velvety reddish brown petal with variable metallic blue markings in the centre of it.

Another endemic orchid is the Maltese pyramidal orchid (orkida piramidali ta’ Malta) but the best known Maltese endemic is Malta’s national plant, the Maltese rock centaury (widnet il-baħar). 

It was first described by Stefano Zerafa a Maltese doctor with a keen interest in the botany of the Maltese islands.

The word endemic is often confused with indigenous. An indigenous species is a plant or animal that is native in a particular place. The opposite of indigenous is non-native. 

In the Maltese countryside we find many species of non-native species including the Cape sorrel (ħaxixa Ingliża) a native of South Africa which was introduced in Malta in the early 19^th Century.

Endemism on the other hand means that a species is found in a defined area. Thus Maltese endemic plants and animals are found in Malta and nowhere else in the world.

 There are also regional endemics. In the case of Malta these would be restricted to Malta and some small neighbouring islands such as Lampedusa, and Pantelleria or Sicily.

Many endemic species are found on islands as a result of biological isolation which allows a species to evolve separately and differently from the same species in another area. 

The number of endemic species in the Maltese islands is lower than on other Mediterranean islands. 

This is probably a result of millennia of human pressure which must have led to the extinction of many species.

Endemic species are considered as internationally important. 

Because of their restricted range they are often in danger of extinction or given a vulnerable status are often protected by means of national and international legislation. 

This article was published in The Times on 11.04.2012

How the wild rabbit was tamed

The wild rabbit is not indigenous to the Maltese islands but it has been here for so long that it is now considered as part of the Maltese fauna. 

The rabbit originated in the Iberian Peninsula.  

From there it was taken to other countries and is now found throughout Europe. I

t was probably introduced in Malta by the Romans or possibly by the Phoenicians. 

Malta was one of the stops of the Phoenicians as they sailed across the Mediterranean their western colonies and their homeland and they could have released rabbits on the Maltese islands to ensure a supply of fresh meat during their journeys. 

The rabbits survived in the Maltese countryside and eventually provided meat for the local population. 

The Knights of St John issued several edicts to restrict or prohibit the local population from hunting rabbits.

In 1773 the restrictions even resulted in a revolt known as the Rising of the Priests.

It is not known when rabbits started to be domesticated in the Maltese islands. 

Some farmers used to keep a doe enclosed with four stone walls each between 80 and 100 cm high. 

The doe was well fed and was too heavy or too lazy to jump out. Males on the other hand would jump inside at night to mate. 

This provided the farmers with a supply of meat close at hand. 

These rabbits were probably the progenitors of the local domestic rabbit known as ‘tax-xiber’.

Wild rabbits are usually a pale sandy brown or greyish with white underparts and different colour varieties can be found in the same area.

Wild rabbits are still relatively common in the Maltese countryside but they are rarely seen because they emerge to feed at dawn and dusk and are very timid as a result of centuries of hunting. 

At the Għadira Nature Reserve, where hunting has been prohibited since 1980, many rabbits have become tame and active during the day and can be seen regularly by those visiting the reserve which is open to the public on weekends. 

This article was published in The Times on 04.04.2012

Plant that looks like a lamb’s tail

The small white flowers grow on a columnar stalk that looks like a lamb’s tail hence its Maltese name, denb il-ħaruf abjad.

The flowers are so small that to appreciate the beauty of this flower you should move in close and if possible use a magnifying glass to study the details of the individual flowers.

The white mignonette grows in Europe, Asia and North Africa but has also been introduced in the Americas and Australia. It is now also cultivated as a garden plant. 

Garden varieties can grow up to a metre high but the wild plants found in the Maltese islands hardly ever grow half as tall. 

This species grows mainly in disturbed habitats and is commonly found throughout the Maltese islands. It can be seen flowering between December and May.

Mignonettes were grown in Victorian England in pots and placed on windowsills to counteract the noxious smell of the city air with their scent. In Roman times the plants were used to produce a sedative and to treat bruises. An oil, extracted from the flowers, is used in perfumery.

The yellow mignonette, a species closely related to the white was also of use. A yellow dye called weld was produced from its roots as far back as 3,000 years ago. Dye production stopped at the turn of the 20^th century when cheaper synthetic dyes became available.

The yellow mignonette is also found in the Maltese countryside but unlike its relative it is very rare. In Maltese it is known as denb il-ħaruf isfar. If you are lucky you can find this plant in flower in April and May.

Both species are rich in nectar and pollen and attract large numbers of butterflies and bees. 

This article was published in The Times on 28.02.2012

Scented Maltese stocks

The Maltese stocks is a special plant because like the national plant (the Maltese centaury – Widnet il-baħar) it is endemic to the Maltese islands. It is known in Maltese as Ġiżi ta’ Malta, because it not found growing wild in any other country. 

The Maltese stocks is not considered as a separate species but as a subspecies flowers from March to May. Another race which is not indigenous to the Maltese islands, the garden stocks (Ġiżi komuni) was introduced in Malta as a garden plant but can be found growing wild in a number of areas especially on the fortifications at Valletta, Floriana, Tignè and Manoel Island. 

The Maltese race was first described by a local and two foreign botanists in 1988.

It is a perennial plant belonging to the mustard family. It is very rare in Malta but less rare in Gozo. It is an endangered species and is protected by law.

Other species of stocks can be found in the Maltese islands. 

The Mediterranean stocks, known in Maltese as Gizi tal-baħar, is an annual plant with pale violet flowers. Until 20 years ago it grew mostly in disturbed ground along the extreme east coast of the Malta but has now spread to other areas especially along the Sliema, San Giljan and Baħar iċ-Ċagħaq coast and is much more common than it used to be. 

The increase in range probably started by the dispersion of the seeds when a strong east wind blew them across the Grand Harbour to the other side of the Valletta peninsula from where it continued to expand its range further west. 

This species has an interesting mode of dispersion as, when the seeds have become ripe, the plant breaks off at the base and tumbles in the wind leaving a trail of seeds along the way.

Another species is the night-scented stocks (ġiżi tal-lejl) which is non-indigenous and rare. 

This species is of Eurasian origin and is often grown in gardens, especially in cooler regions, mainly for its pleasant scent which is most noticeable during the evening and at night.

This article was published in The Times on 21.03.2012

A mollusc in the shape of a heart

Rough seas can deposit very interesting creatures on the shore.  

A walk on the beach after a storm can be very rewarding especially for those who do not dive or snorkel and have to rely on the waves to see some of the creatures that live below the surface.

Many creatures are too fragile to survive the pounding waves intact but many mollusc have very strong shells and remain intact even after a considerable amount of pounding.

Cockles have strong, compact heart-shaped shells that can be rolled over the sand and banged without damage to the living mollusc. 

About twenty species are found in the Mediterranean of which ten have been recorded in Maltese waters. 

The cockle shell, known in Maltese as xedaq, is common in sandy bottoms while the slightly smaller edible cockle, known in Maltese as arzella tal-Marsa prefers brackish water such as is found in estuaries.

Cockles are bivalves, that is, molluscs whose shell is made up of two opposing valves attached together by means of a flexible ligament.   

About 9,200 species, of which 8,000 live in the sea, are known to exist. These range in size from miniscule species to the giant clam which can grow up to 200 kilograms. About 230 species have been recorded in the seas around the Maltese islands with another two species live solely in fresh water.

Some species live attached to solid surfaces while others bury themselves in sediment. Scallops one of which is known in Maltese as pellegrina are free living and can escape from predators by clapping the valves together and creating a jet of water to swim away from danger.

Most bivalves are edible although relatively few species are collected for consumption. Nowadays large numbers are farmed in many parts of the world not only for sale in food markets but also for the cultivation of pearls. 

This article was published in The Times on 14.03.2012.

Fascinating organisms

200 lichens are found locally

Last Saturday I gave a lecture about nature photography to group of young people. I was surprised by their knowledge of plants and animals as they were able to easily identify most species of plants and animals that I showed them.

However what surprised me more was the fact that none of them could tell me what lichen is.

This was surprising because lichens are common everywhere being able to grow in the most unusual places including  bare rock and walls even in urban areas. About 200 lichens have been recorded in the Maltese islands but I am sure that with some effort more unrecorded species can be found.

Lichens are unusual because each species is made up of two organisms, a fungus and an alga, living intimately together. This gives lichens the ability to survive under harsh conditions where no other organism can survive.

In some cases the fungus and alga which make up a lichen can be found living separately in nature but in many cases the two organisms have become so dependent on each other that one can not survive without the other.

Lichens do not have leaves or roots and absorb nutrients directly through their surface. This leaves them susceptible to air pollutants which accumulate in their body without being eliminated. 

Lichens can tolerate different concentrations of pollutants with some species dying at lower levels than others. This makes lichens excellent biomonitors and many species are used to indicate levels of environmental pollutants.

Many species of lichen are eaten especially in times of famine despite of the fact that they can be difficult to digest. Many species also contain mildly toxic compounds although few species are poisonous. 

Some species are used to produce dyes including the pH indicator litmus.

This article was published in The Times on 07.03.2012

Wild orchids

Orchids are my favourite group of plants. They are fascinating mainly because they are beautiful and interesting and although there are many species none of them is common.

Orchids have been arousing passions for a long time. In the Victorian era adventurous individuals embarked on orchid hunting trips in central and south America and Asia mainly to collect specimens for gardeners and horticulturalists in Europe and the USA. They often went back home with large numbers of rare species and long tales about their dangerous expeditions. 

Today many orchids are legally protected and it is not allowed to collect or export them. Although illegal trade in orchids still exists modern orchid hunters collect images. They are equipped with cameras, identification books and notebooks and often publish their results in specialist websites. Some restrict their hunting to a particular country or area while others travel and wide.

In Malta orchids can be found from the end of December to early June most species are in flower in March and April. 

Thirty eight species of orchids have been recorded in the Maltese islands. Over the past two decades the number of recorded species has increased partly because new species have been found by plant enthusiasts but also because what was considered as one species, the brown orchid, is now considered to be five different species. 

These species belong to a group known as the insect orchids. Male insects, especially bees and wasps, are attracted to the flowers which look like female members of the species. They land on them and attempt to mate. While their attempts to mate are unsuccessful they unknowingly end up with pollen on their back which is then transferred to another orchid of the same species which manages to trick them into landing on it. 

Some species of orchids enhance their performance by producing chemicals known as pheromones similar to pheromones used by female insects to attract males.

Finding, photographing and identifying orchids is an interesting and challenging hobby that can give days, weeks and months of satisfaction.

This article was published in The Times on 29.02.2012

Surviving the bitter cold

Last Sunday’s sunshine and the relatively warm temperature was welcome especially after the cold wet days that we had been experiencing throughout most of this month. 

As I do on most Sundays I spent the morning photographing nature. I was not expecting any insects but was surprised to see a solitary asphodel bug (seffud tal-berwieq). 

This species which is usually seen from March to May is found mostly on asphodels. It was standing motionless on a leaf trying to warm up its body. It did not move away when I moved very close to it with my camera. 

This was not surprising as even though the low winter temperatures made it lethargic it normally does not bother to conceal itself or run away from danger as like other brightly coloured insects it felt secure in the knowledge that predators, especially birds are unlikely to harm it. Predators learn that animals with warning colours are inedible because they are either foul-tasting or poisonous.  

The presence of this insect made me think about how insects and other animals survive the winter. Many birds avoid cold weather by migrating to warmer parts of the world but in Europe very few insects migrate and their journeys are not as long and regular as those of birds. 

Some adult insects find a sheltered place usually underneath a stone or bark or in a crack in which to spend the winter. Others die as soon as the weather starts to cool but leave behind them eggs or pupae which will continue their lifecycle with the onset of warmer weather.

Malta’s only amphibian, the painted frog remains active throughout the winter as this is also the time when water, which is essential for this animal to survive, is present but the reptiles including the lizard, geckos and chameleon are inactive throughout most of the winter and venture out only on warmer days.

This article was published in The Times on 15.02.2012.

A kingdom of... fungi!

Fungi are very common everywhere and play an important role in the decomposition of organic matter. An uneaten piece of fruit or any other food within a short time becomes covered with a layer of mold which is nothing but the reproductive bodies of fungi. 

In nature these fungi recycle the nutrients which end up in the soil thus becoming available again for other plants.

Mushrooms are the fruiting bodies of a variety of fungi that generally have a stem on which the familiar gilled structure grows. The best known species are the cultivated edible species. 

Until a few decades ago, fungi were considered as part of the plant kingdom but now they form part of a kingdom. This is because although they have characteristics in common with plants, animals and bacteria they evolved separately from them. They have their own characteristics but are more closely related to animals than to plants.

About 100,00 species of fungi have been described although it is believed that hundreds of thousands if not millions more are still to be discovered. In Malta about 300 species have been recorded although this number does not include the microscopic species.

While fungi can cause serious diseases in humans they play an important role in the pharmacological and food industries. Perhaps the best known antibiotic is penicillin which was discovered by Alexander Fleming in 1928 when he noticed that a fungus which was contaminating his bacteria specimens was actually killing the bacteria. 

Another closely related species is used to inoculate cheese such as the Stilton and Roquefort to give them a unique taste and texture.

Baker’s yeast, a single-celled fungus, is used in the production of bread while another species of yeast is used in fermentation which leads to the production of alcoholic drinks. Other species are used in the fermentation of Soya beans in the production of soy sauce.

This article was published in The Times on 08.02.2012

Crocuses from sands of time

Next time you go for a walk in the countryside especially in areas with rocky garigue, look out for the brightly coloured sand crocuses which are starting to flower at this time of the year. 

Sand crocuses are scientifically known as the romulea a name derived from Romulus, one of the legendary founders of Rome, because whoever gave them their name found large numbers of these plants growing around the Italian city.

The romuleas, of which there are about 80 species, are found in Europe, North Africa and South Africa. 

They form part of the iris family which is characterised by having linear or sword-like leaves. 

The leaves of the sand crocuses are in fact look like green threads.

Until a few decades ago two species of romuleas were recorded in the Maltese islands with one species being divided into four varieties. 

These varieties have now been designated as species and we now have five romuleas present in the Maltese islands although to the untrained eye the five species are so alike that it seems next to impossible to tell apart.

Some species of romulea are cultivated as garden plants although they are not as popular as the larger crocuses.

The violet romulea (żagħfran tal-blat biċ-ċentru roża) is very rare and one is unlikely to meet it unless looking specifically for it. Another species, the Maltese romulea, (żagħfran tal-blat ta’ Malta) is endemic to the Maltese islands, although it is very rare and might already be extinct.

Some romuleas are very similar to crocuses with which they share the same habitat. Although they are both members of the iris family they belong to separate groups and have evolved separately. 

Their similarity is a result of the fact they the two groups of plants share the same ecological niche have evolved in the same way to deal with the same environmental conditions a process known as convergent evolution. 

This article was published in The Times on 01/02/2012