The rat that lacks pigment

Some time ago I photographed a strange looking rat that was so tame that it came to within two or three metres of me and allowed me to take many pictures of it before it walked calmly away. 

The rat had white markings on the face showing that it was an albinoid rat.

Albinism is characterised by complete or partial absence of pigment in the skin. It can occur in all vertebrates including humans. The lack of pigment can be partial or complete and can also effect the hair and eyes.

Albinism is not often seen in nature. The lack of pigment results in loss of camouflage and albinistic animals are easily spotted by predators. In areas with no predators albino animals can have a normal life expectancy. A Spanish sparrow (għammiel tal-bejt) with large patches of white on its wings used to breed in a ventilator close to where I live and managed to survive for many years.

Several albino animals have been purposely bred for particular characteristics. The best known are albino rabbits and rats. Albino rabbits are said to have a better taste while albino rats are used extensively in laboratories for biomedical studies and experimentation.

It is said that these rats are the descendants of rats caught around 1800 by English rat-catchers for ratting, a blood sport in which trained dogs were lowered in pits full of rats to kill as many as possible in the shortest time possible. Rats which exhibited any albinism, instead of being thrown in the pits, were kept for breeding and exhibition and these became the stock from which today’s laboratory rats are descended.

Two species of rat are found in the Maltese islands; the brown rat (far tal-kampanja) and the black rat (far iswed). Both species of rat can by found in urban and rural areas. 

They are very common animals that can be carriers of disease and can cause a lot of damage to crops and stored food. 

This article was published in The Times on 12.10.11

The amazing praying mantis

Last Sunday I was photographing a dragonfly resting on top of a dry plant when out of the corner of my eye I saw a brown praying mantis. 

Praying mantises are amazing insects. They are long and as thin as a stick with a pair of large eyes on the sides of a flexible head. The head can swivel in many directions which allow the mantis to scan its surroundings for predators and prey. The most unusual feature of these insect is that the front legs have been modified into very effective hunting instruments.

The praying mantis is known in Maltese as debba tax-xitan , devil’s mare in English. Mantis is derived from the Greek word for prophet. Three species of praying mantises are found in the Maltese islands. 

This is a very small number when compared to the approximately 2,200 species found in the world. Some of the larger species are capable of catching larger animals including lizards, frogs, fish rodents and even birds.

Most species are diurnal, that is, they are active during the day, but the males of some species fly at night to visit females which they detect by means of pheromones. 

By flying at night they can avoid day-flying predatory birds and to avoid bats some have organs capable of detecting the echolocation sounds of bat which allows them to take evasive action when bats are hunting in the vicinity. 

After all the effort and risks incurred to find a female, most male praying mantises make the ultimate sacrifice by allowing the female with which they had just copulated to eat them and so providing her with nutrients to produce the eggs. 

This article was published in The Times on 5.10.11

Flesh flies breed on living or dead organic material

Flesh flies, as their name implies, breed on living or dead organic material, mainly flesh. Their maggots live in dead animals, dung or decaying vegetable matter and sometimes in open wounds of mammalian species. 

Some species are internal parasites especially of beetles and grasshoppers while others live in bees and wasps’ nests.

About 30 species are found in the Maltese islands. Most are dark with light stripes but in many cases it is difficult to tell species apart unless they are studied microscopically. 

In many species the female is larger than the male. The most common species, known in Maltese as dubbiena tal-laħam, is larger than the common house fly. It can be found on decomposing organic material as well as on flowers.

These insects which are found throughout most of the world are not only a nuisance but can also be important vectors of diseases including leprosy. Sometimes they are also important as pest control agents and can be beneficial in fruit tree orchards and in forestry plantations.

Flesh flies have been extensively studied especially because of their importance in forensic science. Flesh flies do not lay eggs. The eggs hatch inside the female fly which then ‘gives birth’ to the maggots. 

Different species place their young in animals that are at different stages of decomposition ranging from freshly dead to bloated or decaying. This makes it possible for entomologist to accurately give the date or sometimes even the time of death of a corpse.

There is a tendency to classify insects as being either good or bad. Flies are automatically deemed as bad and therefore to be annihilated. But the living world is not that simple. 

Many species of flies can cause problems but at the same time they also help to break down organic matter and help to recycle it. 

Flies reduce the time required for a corpse to decompose and without them we would see more dead animals lying around. 

This article was written in The Times on 28.09.11

Watching raptors migrating is a rewarding experience

Honey buzzard (Pernis apivorus)

September is raptor migration month. Every year large numbers of birds of prey such as honey buzzards (kuċċard), several species of harriers (bugħadan), eagles (ajkli) and falcons (isqra) fly over the Maltese islands while travelling from their breeding grounds in Europe to their wintering grounds in Africa. 

Malta is on one of their routes because these birds travel on land and avoid as much as possible crossing large stretches of open water. 

Raptors travel mostly by making use of hot air currents, known as thermals, to soar with the minimum of effort. We are all familiar with films and documentaries showing vultures soaring in search of dead animals.

Migrating raptors tend to congregate mainly but not solely at Buskett. Birdwatchers have been monitoring these magnificent birds for more than three decades and have become experts at raptor identification, being able to not only to tell species apart but also sexing and aging migrating birds.

Raptor watching in Malta has become very interesting and exciting. Thirty years ago the challenge was to count the birds including the large numbers that were illegally shot while avoiding being shot yourself. This situation has changed and bird shooting in and around Buskett is mostly under control. As a result of this the number of migrating raptors has increased and birdwatchers are getting spectacular views of these birds as they fly low in search of a place to land.

Watching raptors on migration is an incredibly rewarding experience and I urge readers to go to Buskett to experience this natural phenomenon. Anybody wishing to give it a try should go to Buskett this afternoon from three o’clock onward where a group of experienced birdwatchers will be near the cart ruts site known as Clapham Junction to help those present to get the most out of the experience.

This article was published in The Times on 21.09.11

The moonflower – an alien species

The moonflower is another alien species that first came to Malta as a cultivated garden plant and which is now thriving in the Maltese countryside. Although it is not as common as some other alien species such as the ubiquitous Cape sorrel (ħaxixa ngliża), when present, it is very noticeable because of its large leaves and white or pink flowers.

The flowers of the moonflower open at night and close early in the morning. Their light colour, large size and fragrance make it easier for the flowers to be seen in the dark especially by moths particularly the hawk moths.

The moonflower is a native of the tropical and sub-tropical parts of the American continent. It can be found all the way from northern Argentina to Mexico and Florida.

In Malta this species usually flowers between March and July but in gardens, where it is watered in summer, and in humid valley bottoms it can continue blooming until much later.

This plant is rich in sulfur, an element which is still used in vulcanisation of rubber, a process discovered by Charles Goodyear in 1839 but in southern America, the natives had been using the moonflower to vulcanise the latex of two plants to make bouncing rubber balls 3,000 years before him.

The moon flower belongs to the convolvulus or bindweed family the group in which we find many species of bindweeds which are known in Maltese as leblieb as well as the morning glories. It is in fact it is most closely related to the garden morning glory, the popular garden plant. 

A number of closely related species are used as food while others are used medicinally. Others contain psychoactive substances which were used in religious and spiritual ceremonies to induce an altered mental state similar to that from modern drugs such as LSD, opium and some mushrooms. 

This article was published in The Times on 14.09.11

The flower that blooms at 4 p.m.

Marvel of Peru (Mirabilis jalapa)

The marvel-of-Peru or as it is known the four o'clock flower gets its English names from its country of origin and from its habit of opening its flowers in the late afternoon. 

It is a widely cultivated plant that is also found growing wild in the Maltese countryside. In Maltese it is known as ħummejr. 

It is believed that this plant was first exported from the Peruvian Andes in 1540.

The plant grows along country roads and lanes and can be easily recognised by its large number of brightly coloured flowers. 

The flowers can be of different colours ranging from yellow to red with some flowers being white, striped or marked with different colours. Sometimes differently coloured flowers grow simultaneously from the same plant. More surprisingly the colour of the flowers growing on a particular plant change in colour as the plant matures. Thus a plant that starts off by having yellow flowers ends with dark pink flowers while a plant with white flowers starts producing light violet flowers.

The marvel of Peru flowers from late spring to early autumn. The flowers remain open well after sunset and are pollinated by long-tongued moths such as the hawkmoths which are attracted to the flowers by a strong sweet-smelling fragrance.

Parts of the plant are said to be very toxic and can have effects similar to that of LSD. They can cause digestive disorders and abortion. 

As with many poisonous plants this species also has medicinal value. It is used as a laxative, or to treat constipation and to expel intestinal worms. The flowers are used in food colouring particularly as a crimson dye which is used to colour cakes and jellies. 

This article was published in The Times on 07.09.11

The protein-rich pecan nut

Pecan (Carya illinoinensis)

The pecan, is a large tree indigenous to the southern states of America and Mexico. 

The Spaniards brought the tree to Europe in the 16th century. It was later planted in parts of Africa and Asia. This tree is best known for its fruit which is referred to as a pecan nut. In Malta the tree has been planted in a number of places including Buskett Gardens. Several large specimens can be seen along the path leading to the valley known as Wied il-Luq as well as in Wied il-Luq itself.

The pecan tree is a deciduous tree. The flowers, which are wind pollinated, appear in spring. Fertilised flowers produce an elongated fruit consisting of a green husk surrounding a structure known as a nut. As the fruit matures the husk becomes dark brown. In October and November the fruit drop onto the ground.

Although this species is not well known in Malta, some people know exactly when to visit Buskett gardens to collect pecan nuts. Pecan trees can produce large quantities of fruit and some manage to fill up whole baskets with this edible fruit.

In Maltese the pecan tree is known as siġra tal-pekan and the fruit is called ġewż tal-pekan.

The nuts can be eaten fresh. In other parts of the world they are used as an ingredient for several desserts the best known being the pecan pie.

The trees that grow at Buskett Gardens are very large. Although they must have been planted several decades ago they are likely to be around for many more as in good conditions pecan trees can live for more than 300 years.

Pecan nuts, like walnuts (to which they are related) are protein-rich and a good source of unsaturated fats. Eating pecans reduces the levels of LDL cholesterol and in women the risk of gallstones. 

This article was published in The Times on 31.08.11