Sunday, March 24, 2013

The European bee-eater

European bee-eater (Merops apiaster)

The European bee-eater looks like a large colourful swallow. It is often seen in flocks and is usually heard before being seen.

During the past couple of decades it became more common in Malta and can nowadays be seen migrating regularly, often in large flocks, during both the spring and autumn migration

Until about a hundred years ago it used to breed in the Maltese islands and nests were recorded from Ramla l-Ħamra in Gozo but stopped doing so because of human disturbance. 

During the past couple of years it started breeding again in one locality on mainland Malta. This resumption in breeding coincided with the abolition of hunting during the spring migration. They nest in colonies in sandy banks near rivers but can also breed in coastal sand dunes and sloping soil mounds. 

The nest consists of a lined depression at the end of a long tunnel excavated by the bee-eaters by using their bill and feet. Both the male and the female take care of the eggs, which are brooded for about 3 weeks.

Bee-eaters prefer to live in warm climates. The European bee-eater breeds in southern Europe, North Africa and western Asia and winters in tropical Africa, India and Sri Lanka.

In Maltese it is known as qerd in-naħal because it eats insects especially bees and wasps. It catches its prey in the air flying around and catching the flying insects in its beak either during continuous flight or more commonly by sorties from an open perch, usually a branch on the top of a tree or large bush. 

Before eating its meal it repeatedly hits the insect on a hard surface to remove its sting. Bee-eaters are colourful birds. The species seen in Malta has brown and yellow upper parts and green wings.

There are 26 different species of bee-eaters in the world. Most are found in Africa. They are all characterised by richly coloured plumage, slender bodies and usually elongated central tail feathers. All have down-turned bills and pointed wings. 

This article was published in The Times on 21 October 2009.

The jujube, a small deciduous tree with fruit

Jujube fruit (Ziziphus jujuba)

The jujube is also known in English as the red date or chinese date. In Maltese it is known as żinżel. It is a small deciduous tree that grows between 5 and 10 metres high.It is grown primarily for its fruits and sometimes for the wood. 

It has been cultivated for centuries and its natural distribution is not known but it is believed to have originated in southern Asia between Lebanon and northern India, the Korean peninsula, and southern and central China. 

It is claimed that it also lived in southeastern Europe although its occurance there is most likely to be a result of human introduction.

In Malta it has been cultivated in a few areas including Mtaħleb where a few trees can still be found. These trees produce fruit in September and October. When immature the fruit is smooth-green, with the consistency and taste of an apple. It becomes dark red to purplish-black when mature and eventually it becomes wrinkled, looking like a small date. There is a single hard stone similar to an olive stone.

The jujube has been cultivated in the Indian subcontinent for thousands of years. It has several medicinal uses and the fruits have been used medicinally in both Chinese and Korean traditional medicine where it is believed to alleviate stress. 

Freshly harvested as well as candied dried fruits are often eaten as a snack.  

Jujube fruit is also made into tea and is even available in the form of teabags. In parts of Asia it is also possible to find jujube juice, jujube wine, jujube vinegar and jujube pickles.

The jujube’s sweet small is said to make teenagers fall in love, and as a result in the Himalayan region men take a stem of sweet-smelling jujube flowers with them or put it on their hats to attract women. In the traditional Chinese wedding ceremony, jijube and walnut were often placed in newlywed’s bedroom as a sign of fertility. The leaves are also used as a potpouri to help keep the houses smelling fresh, clean and insect free. 

This article was published in The Times on 14 October 2009.

The slant-faced grasshopper


The Mediterranean slant-faced grasshopper is a slim, delicate grasshopper with a cone-shaped face and triangular antennae. It lives either humid or dry habitats with vegetation or sand in which it is very well camouflaged. It can be found between mid-summer and early autumn in many parts of the Mediterranean including Malta.

Many species of grasshoppers, including the slant-faced grasshopper which is known in Maltese as ġurat ta’ rasu twila, have two colour forms as they can be either green or brown. 

These colours allow these insects to disappear in their surroundings. This is one of the most common forms of cryptic colouration known as camouflage. 

More than anything else the success of good cryptic coloration is to break the outline of a creature’s body. Many species of insects and other creatures including fish, reptiles and mammals use camouflage as a means of defence.

The type of camouflage a species will develop depends on several factors. The most important factor is the environment in which the species lives. Another important factor is the physiology and behaviour of the animal. Furred animals need different camouflage than those with feathers or scales. 

The nature of the predator also makes a difference. Thus if the predator does not see colours the animals will not need to match the colour of its surroundings. Cryptic coloration can change as well in response to changes in the environment such as some foxes and the weasel that become white in winter so as to be able to disappear in the snow. Some insects including many grasshoppers are green during the wetter months while the generation that hatches during the hotter months would be brown. 

It is believed that the temperature of the egg determines the colour of the adult insect. 

Warmer eggs produce brown insects which would blend with the dry vegetation. 

This artcle was published in The Times on 7 October 2009.




Saturday, March 23, 2013

The yellow wagtail


The yellow wagtail is a common spring and autumn migrant. It is often seen in flocks especially at dusk when one can see them flying in the direction of reed-filled valleys where they roost. During the day it can be seen picking insects from the ground in fields and other open areas especially in valleys with water courses.

There are several races of yellow wagtail. These normally live in different areas but in Malta they can often be seen together. The male birds of the various races have different head colour which makes it easy to tell them apart but the females are similar and can be assigned to a particular race by simple observation.

The yellow, which is known in Maltese as isfar, is one of three species of wagtail that visit the Maltese islands. It breeds throughout most of temperate Europe and Asia as well as in Alaska. Most birds migrate to Africa and south Asia but some populations in Western Europe remain in the breeding areas throughout the year.

The other two species of wagtail that can be seen in Malta are the white wagtail (zakak abjad) and the grey wagtail (zakak tad-dell). The white wagtail is very common during the autumn and winter months. It can be seen throughout urban areas and in the countryside. The grey wagtail is also seen during the winter months but it is a very shy bird and often flies away with a typical loud call when disturbed.

Wagtails are characterised by their long slender body and by their constant waging of their tail. This characteristic is poorly understood and there are various theories about why it occurs. It has been suggested that it may flush up prey, or that it may signal submissiveness to other wagtails. Recent studies have suggested that it is a signal of vigilance to deter potential predators.

This article was published in The Times on 30 September 2009.

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. 

Thursday, March 21, 2013

The amusing dung beetle


Dung beetles belong to the scarab beetle family which also includes the rhinoceros beetle (buqarn kbir), the barbary bugs (busuf) and the emerald chafer (għawwar dehbi).
About 33 species of scarabs are found locally. One species is the dung roller, known in Maltese as the ħanfusa tad-demel. This species makes a ball out of dung and then rolls it in a straight line to a spot where it will bury it in the soil.
Watching a dung beetle travelling with a dung ball can be quite entertaining. The journey starts with the beetle head down on its two front legs and then walking backwards while rolling the ball with its hind legs.
The journey usually takes the form of an obstacle race that can include seemingly insurmountable vegetation, pools of rainwater and large stones. To make the journey even more hazardous, other dung beetles start appearing on the scene as if out of nowhere, all trying to take away the ball from the original owner.
This species is said to be scarce in the Maltese countryside but while photographing one recently, another five appeared, showing that at least in some parts of the countryside they can be relatively common.
Dung beetles play an important role in the countryside. They help to recycle nutrients and make them available for plants. They also clear cattle-grazing areas of dung which would otherwise attract flies that can carry disease.
Several species of dung beetle from South Africa and Europe were introduced in Australia to improve cattle pastures.
Other species of dung beetle can be found in the Maltese countryside. The horned dung beetle, known in Maltese as ħanfusa barri tad-demel, is smaller and has a pair of long horns on its head.
This article was published in The Times on 20 March 2013.

Tuesday, March 19, 2013

The cicada

Cicada (Cicada orni)

Cicadas are insects with a large eyes and transparent wings. The species found in Malta, known as weżieq ta’ bi nhar, can be heard calling throughout the summer wherever there are trees even in urban areas. It is one of about 2,500 species of cicada found in temperate and tropical climates around the world. Cicadas are harmless to humans as they do not bite or sting but they can damage crops, trees and shrubs.

The noise of the cicada is made by means of a pair of organs known as timbals which are found on the side of the abdomen. These consist of regions of the exoskeleton that are modified to form a complex membrane with thin membranous portions and thickened ribs. By contracting the internal muscles attached to the timbals these are buckled inwards making a clicking sound. As the muscles are relaxed the timbals go back to their original position and make another click. This movement is repeated rapidly to make a continuous sound which is amplified in enlarged chambers derived from the tracheae which serve as resonance chambers. Every species of cicada has a particular song by which it can be identified.

Cicadas normally live in hot environments and are often most active during the hottest times of the day.
Only males can sing but both males and females have organs to enable them to detect sound. In some species the male can disable this organ while singing.  Some cicadas are able to produce very loud sounds which are considered to be amongst the loudest of all insect-produced sounds while some small species have songs which are so high pitched that they are inaudible to humans.

In addition to the mating song, many species including the species found in the Maltese islands, have a distress call which is usually a somewhat broken and erratic sound emitted when the individual is seized.
A number of species also have a courtship song which is produced after a female has been attracted to a male by its calling song.

This article was published in The Times on 16 September 2009.
 

The sea squill – the harbinger of autumn

Sea squill, Ghansar (Uriginea maritima)

The sun has been shining relentlessly on the Maltese countryside for the past five or six months and by now the countryside is parched dry. There is very little green vegetation and very few flower. 

The sea squill is one of the few species of plants that flowers at this time of the year. It is a very common plant, which is impossible to miss by anybody visiting the countryside at this time of the year.

The squill has an unusual flowering pattern.  The tall flowers appear in late summer before the autumn rains when the plant has no leaves. They sprout from a large bulb directly out of the dry soil. The tall fleshy leaves do not appear before the arrival of the autumn rain and dry completely in spring. By flowering in summer the sea squill manages to avoid competition from other flowering plants and attract large numbers of bees to its flowers.

The sea squill has several common names including sea onion and. red squill. Red squill probably refers to a variety of the plant that has red-tinted flowers instead of the more common white. The bulbs grow very close to the surface of the soil and can be quite large. 

They sometimes weigh more than two kilograms. In areas of high soil erosion, they are sometimes uncovered completely and they end up laying on the surface of the soil until they eventually die.

The squill belongs to the lily family in which we also find the asphodels, tulips, garlic and the beautiful star of Bethlehem. The sea squill is known in Maltese as għansar. Another species of squill, known in Maltese as għansar tal-ħarifa, flowers in early autumn. This species also flowers before the leaves appear but it is much smaller and cannot be mistaken for the earlier flowering species.

It has been used for medicinal purposes since ancient times. In small doses it stimulates the heart and is a diuretic but in larger doses it is an emetic and poisonous. The squill’s medicinal properties have been known since Egyptian times. Their use has been recorded as far back as 1500 BC, while in Greece both Pythagoras and Hippocrates, used it in the 6th and 5th centuries BC. The juice of the bulb causes blister when they come in contact with the skin. It has been used as a rodenticide and is being studied for its insecticide properties.

In Israel the sea squill has gained an almost iconic status and is popularly known as the ‘harbinger of autumn’ due to the fact that the flowers pop out all over the country at the end of the dry summer, some time before the first rains. During the New Year celebrations, the Greeks hang the bulbs of the sea squill in the house as part of a fertility rite. 

This article was published in The Times on 9 September 2009.

Saturday, March 16, 2013

Swallowtail butterfly (Papilio machaon melitensis)

In recent days I saw several swallowtail butterflies in different localities, including a pair which I photographed at Pembroke.
The recovery of the swallowtail population is good news not just because the swallowtail adds beauty to the Maltese countryside, but more importantly because the swallowtails found in the Maltese islands are an endemic race found nowhere else in the world. If it becomes extinct in the Maltese islands this race will be lost forever.For the past four or five years I noted that there were fewer butterflies in the Maltese countryside than in previous years. The swallowtail, like other species, had become very scarce. This could be because of the heavy rain of five years ago, which might have destroyed a large number of overwintering eggs and pupae.
The swallowtail is our only endemic butterfly. It is so special that it should be declared Malta’s national butterfly. We already have a national plant, national bird and national tree. It is now time to have a national butterfly as well.
Its scientific name is Papilio machaon melitensis, melitensis showing that it is a Maltese race.
In Maltese it has several names. It is known as farfett tar-reġina (queen’s butterfly), farfett tal-busbies and farfett tal-fejġel, fennel and rue being its two food plants. It is also known as farfett tal-lira.
This species is a good candidate to be declared our national butterfly because it is beautiful and attractive and is easily identified. It does not harm crops, it does not spread disease and it does not have any negative connotations.
A number of countries already have national butterflies. In the US it is being proposed that the monarch becomes the national butterfly, while most states have a butterfly as a national state symbol.
National plants and animals are looked upon by the citizens of a country and by outsiders as symbols that represent and unite their country.
They can also help draw attention to that species, particularly for the need to protect and conserve them. In Malta this has already happened with the blue rock thrush (merill), the Maltese centaury (widnet il-baħar) and the sandarac gum tree (għargħar), Malta’s national bird, plant and tree, which are all well-known and loved species.
This article was published in The Times on 13 March 2013.

A symbol of heraldry and holiness


Southern dwarf iris (Iris pseudopumila)
The southern dwarf iris is restricted to the southern Italian region of Puglia, Sicily and surrounding islands, including the Maltese islands.

The plant, known locally as bellus, is rare and strictly protected in Malta. In the Italian territories it is a common species throughout its range, except in the southeastern part of Sicily – the region which is geographically and biologically closest to our islands.
This species is interesting in more ways than one. It is a perennial plant with evergreen leaves that grow out of an underground tuber which provides nourishment during the leaner periods and allows the plant to flower in winter.
The leaves are sword-shaped and grow between 10 and 25 centimetres. The flowers come in a variety of colours: violet, purple or yellow. Sometimes different coloured flowers can be found together in a single population, but not in Malta; locally, single populations consist only of flowers of the same colour.
Iris flowers have a particular shape that is used as a model for the fleur-de-lis, a popular decorative design used in heraldry and as a religious and political symbol. It is also part of the symbol of the scouting movement.
The flower is also an emblem of the Virgin Mary and because of its three petals, it has been used to represent the Holy Trinity.
The flowering period of this species is from January to May. In Malta it is in flower between January and early March. Further north, this species will come into flower later and remains in flower until longer.
The flowering period depends on the latitude and altitude of the plant. Further north and at higher altitudes, the air and ground temperature tends to be colder and the air warms later than in more southerly regions and closer to sea level.
This article was published in The Times on 6 March 2013.

Sunday, March 10, 2013

Wasps - Predatory flying insects


Wasps are predatory flying insects with two pairs of transparent wings and an ovipositor, which is a tube for laying eggs, which can be modified in various ways. 

In several species the ovipositor is used to sting and inject venom.  Most stinging wasps are predators or scavengers; their ovipositors may be modified to inject venom used for killing prey or for defence. 

In some species one sex may be wingless. In the vegetarian sawflies, the abdomen is broadly attached to the thorax and the ovipositor is rigid; in the higher wasps, the abdomen is flexibly attached to the thorax and the ovipositor is movable. 

The larvae of parasitic wasps consume the bodies of other insects or, in a few cases, consume plant tissue.

Wasps are related to ants and bees but separated from them by having a sting and no hair (bees have hair). Wasps prey on a large variety of insects and it is claimed that every pest species has a wasp species that preys on it making wasps important agents of biological control and they are often used to control agricultural pests.

About 75,000 species of wasps are known, most of them parasitic. Wasps are categorised into two main groups, solitary wasps and social wasps. Adult solitary wasps generally live and operate alone and most do not build nests. Social wasps live in colonies that can have several thousand individuals but in some cases not all members of the colony can reproduce.  In the more advanced species only the wasp queen and male wasps can mate, while the majority of the colony is made up of sterile female workers.

Many species of wasps build nests which could be a simple structure made of mud as is built by some predatory solitary wasps to large complex structures built by social wasps. Wasps do not have wax producing glands like bees instead they create a paper-like substance using wood pulp which is collected from weathered plant material which is softened by chewing and mixing with saliva. The pulp is then used to make combs with cells for brood rearing.

Several species of wasps can be found in the Maltese countryside. The most common are the paper wasps which build colonial nests which are fixed to sunny rock faces, walls and trees and wood. A colony consists of three casts, queen, female workers and males. Males do not have a sting. The two most common species are the common paper wasp (żunżana tax-xehda) and the large paper wasp (żunżana tax-xehda kbira). These two species are very similar and difficult to tell apart. 

This article was published in The Times on 2 September 2009.


Chameleons

Chameleons (Chamaeleo chamaleon)

The chameleon is a territorial creature. A few days after hatching it starts to defend a territory. An adult chameleon will chase away any potential enemy, which it can see from as far away as one metre, and thus one does not normally see chameleons in pairs unless they are approaching each other to mate.

This weekend I found such a couple at Wied Qannotta near Burmarrad. I saw a chameleon resting on the side of a rubble wall. As I was about to take a picture I realised that just behind it, hidden behind some leaves, there was another chameleon. The first chameleon was larger and plumper.

It was a uniform orange-brown. The second chameleon was very thin and had more contrasting colouration mainly brown and light brown. 

The front chameleon started to walk slowly along the wall moving from one stone to another carefully testing every step and continuously turning its eye backwards to look at the second chameleon, which was following closely behind. I observed this behaviour for quite some time as the pair moved along the wall for a distance of about five metres. The second chameleon was never more than a couple centimetres behind and several times while walking grasped the other chameleon’s tail.

At one point they disappeared over the wall but appeared immediately after to continue with their journey. They then entered into a spiny asparagus bush, which was growing out of the wall and disappeared inside. I waited in vain for them to come out again but they failed to appear. 
 
Female chameleons are said to be larger than males. Males are brownish and females greenish but their colour change according to needs and circumstances. The colours can range from black to light yellow sometimes seeming to be orange, red or blue. Colour change depend on several factors the foremost being body temperature. The side facing the sun is usually darker as dark colours absorb heat better than lighter colours. Colours also change when it is afraid or irritated and when a male approaches a female.

Males start approaching females in July. If a female is not prepared for mating she moves away from an approaching male while one that has already been mated changes colour to show her state thus informing other males that they should not approach her. She lays the eggs from October to early December. The exact timing depends on the surrounding environment, as the eggs need higher humidity and the lower temperature both of which depend on the arrival of the first rains of the season. 

This article was published in The Times on 26 August 2009. 



The scarlet darter


 The scarlet darter can be seen from early spring to late autumn often near water but sometimes even in very dry areas a considerable distance away from any aquatic habitat. It is very common in Malta as well as in many of the places where it occurs in central and southern Europe as well as in many parts of Asia and Africa.

The scarlet darter belongs to the genus Crocothemis. Members of this genus are usually small to medium sized dragonflies. They are found in southern Europe, Africa, Asia, Australia and the Southwest Pacific.

The males are usually brightly coloured and very noticeable. Females tend to be dull brown or orange.

Because of their bright colours and peculiar behaviour dragonflies attract a lot of attention and are the subject of many folk tales and legends. 

A couple of weeks ago in an article about another species of dragonfly I wrote about the association between the dragonfly, the devil and hell. In Swedish folklore the devil is said to use dragonflies to weigh people’s souls and that trolls use dragonflies as spindles when weaving their clothes. Trolls have another use for dragonflies – they send them out to poke out the eyes of their enemies. In neighbouring Norway and in Portugal dragonflies are also associated with eyes being known as ‘eye poker’ in Norway and ‘eye snatcher’ in Portugal

In other parts of the world including Wales and the Southern United States they were associated with snakes. On the other hand in East Asia and among Native Americans dragonflies are regarded highly and this culture has influenced the way dragonflies nowadays are looked at in the West.

Dragonflies now feature prominently in Art Nouveau especially in jewellery designs and are used as a decorative motif on fabric and home furniture. In Europe and the United States dragonfly watching, which is being called ‘oding’ from the dragonfly’s Latin species name odonata, is becoming very popular. 

This article was published in The Times on 19 August 2009.

Orb Spiders

Lobed argiope (Argiope lobata)

Orb spiders are a group of large, often colourful, spectacular spiders that are represented throughout most of the world. The lobed argiope (brimba kbira tal-widien) is the largest Maltese spider and is often found in valleys and wooded areas. 

Recently another species of orb spider, the banded argiope, was discovered in Malta. It was noted at the Simar and Għadira Nature Reserves and now seems to have spread to other localities. This is an American species and is not normally found in Europe. The wasp spider is closely related to the lobed argiope. 

It is found throughout Central and Northern Europe, North Africa and parts of Asia. It used to be found in Malta but apparently has become extinct in the Maltese islands. The male spider is much smaller than the female and has no distinctive markings. In the picture he can be seen just above the much larger female spider.

Spiders reproduce sexually. Although fertilisation is internal it is indirect, that is, the sperm is not inserted into the female’s body by the male’s genitals but by means of an indirect stage. 

Before approaching a female the male must ensure that she is of the same species. This is often done by means of complex courtship displays. Sometimes he identifies her by checking the web, which might have characteristics particular to the species. The male argiope spins a web close to that of the female’s and then approaches the female. He then spins a small web in which he places his sperm. 

A female spider may lay up to 3,000 eggs in one or more silk eggs sacs. Some females die after having laid their eggs while others protect the sacs by attaching them to their webs, hiding them in nests or carry them around attached to their body.

Young spiders remain inside the egg throughout their larval stage. They hatch as spiderlings – small, sexually immature but similar to adults. As they grow they moult as their cuticle cannot stretch and cannot accommodate their body as this grows larger. In some species males mate with newly-moulted females which are too weak to be dangerous to the males. 

Ths article was publshed in The Times on 12 August 2013. 


The lesser emperor dragonfly

Lesser emperor dragonfly (Anax partenope)

The lesser emperor is a large dragonfly, slightly smaller than the emperor dragonfly from which it is easily distinguished by its colour and markings. It lives close to freshwater pools but can sometimes even be found in the vicinity of brackish water. Although the adults do move around they generally tend to remain in the vicinity of aquatic habitats.

The lesser emperor dragonfly is found in mid and southern Europe, the near East and Asia as well as in North Africa. The emperor dragonfly is more widespread and common and can often be seen away from water but in some spots the lesser emperor can be much more common.

Dragonflies are very interesting creatures and one can spend a long time observing their behaviour. They are very energetic insects that spend a lot of time flying around to defend their territory chasing away intruders of the same and often of other dragonfly species. They also spend a lot of time hunting small insects. 

Dragonflies have very interesting courtship and mating behaviour, which varies from one species to another. Courtship takes place to ensure that the couple belong to the same species and that the female is ready for mating. The female may also reject the male if the site is not suitable for her to lay the eggs in. The male then grasps the female by the head or thorax and bends his abdomen to mate forming a ‘tandem position’. This might last from a few seconds to several minutes. The female then bends her abdomen underneath the male so that their genital areas touch thus forming a heart-shaped wheel known as the ‘wheel position’. After copulation the pair may separate or remain in tandem depending on the species.

The lesser emperor, unlike most other members of the Aeshnidae family to which it belongs, remains in tandem after mating. The male accompanies the female while she inserts the eggs in living or dead plants and sometimes even in damp mud. The eggs hatch after about three months.

In many parts of Europe dragonflies are seen as evil creatures. In some countries they were believed to come from hell. In Romania it was believed the dragonfly was once a horse possessed by the devil. In Malta dragonflies are known as mazzarell, which is a quill for knitting needles, ċikku ġwiebi and ħelikopter. They where apparently also called debba ta’ l-infern

This article was published in The Times on 5 August 2009.



Saturday, March 9, 2013

The red underwing


At first glance the red underwing looks like a drab coloured moth but the underwings are surprisingly brightly coloured. It spends the day resting on an old wall or on a tree trunk with its underwings well hidden. This pair of wings is uncovered completely only during flight. This helps this species and other related moths to escape from predators, usually birds, which are dazzled when they see the sudden flash of colour appearing as if out of nowhere.

This species of red underwing, known in Maltese as elokata grows up to 88 mm. It can be found in Buskett Gardens and has been found in other areas such as Fiddien where one finds poplars and willow trees on which the larvae feed grow. This species which can be seen between June and September lives in Central and Southern Europe, North Africa, Asia Minor Uzbekistan and Kazakhstan.

The red underwing is one of a number of species of moths known as the Catocala. This genus of moths is characterised by having brightly coloured underwings usually orange, red, yellow or white. The name is a combination of two Greek words, kato, behind and kalos, beautiful. The genus occurs in Eurasia and North America. The larva of most species feed on the foliage of trees and shrubs.

Three other Catocala moths can be found in the Maltese islands. The Catocala conjuncta, known in Maltese as katokala, is rare and has been found only in Buskett Gardens. It is found around the Mediterranean. The larvae feed on the leaves of the oak trees and the adult is seen between July and August. It has mottled brown forewings and crimson-red hind wings. In 2004 it was found in Britain in the Minsmere bird reserve and was given the English name Minsmere crimson underwing. 

Catocala nymphaea, known in Maltese as katokala safra kbira is very rare and has been recorded in Malta only a few times in the summer months. It has yellow underwings and the larva feeds on the leaves of oak trees. Another species with yellow underwings is the oak yellow underwing known in Maltese as katokala safra żgħira, which is also very rare.  

This article was published in The Times on 29 July 2009.

Friday, March 8, 2013

The Maltese spruge


Maltese spurge - Tengħud tax-xagħri (Euphorbia melitensis)
As its name suggests, the Maltese spurge is a plant endemic to our islands and belongs to the spurge family. It grows as a dense shrub usually about half a metre high, although in some places it can grow up to two metres.

The Maltese spurge, known as tengħud tax-xagħri, grows in garigue. At particular times of the year, it can be mistaken for a thyme bush from a distance. This is a result of convergent evolution – when two species have the same characteristics even though they are unrelated.
In this case these unrelated species share many features as a response to the difficult conditions in which they live. A dense, bushy shape and small waxy leaves help to reduce water loss.

Spurges also have a mechanism to defend themselves from herbivores such as wild rabbits and domesticated animals, such as goats and sheep. They produce a poisonous white liquid which can be seen when a part of the plant is damaged and that makes them inedible.
However, this liquid does not protect them from the caterpillar of spurge hawk moths which feed on its leaves and accumulate the poison in their body to protect themselves from predators.
The spurge hawk moth is another endemic species and is known as the Maltese spurge hawk moth.

The liquid is also ineffective against dodder, a parasitic plant known in Maltese as pitma, that obtains its nutrients from its host plant.

The Maltese spurge was first described in 1869 by Filippo Parlatore, an Italian botanist from Palermo. Parlatore was a medical doctor who gave up his profession to be able to devote all his time to botany. He published works on the flora of Sicily and as at that time many naturalists considered Malta to be part of Sicily, he included information about Maltese flora in his studies.

This article was published in The Times on 27 February 2013