Sunday, March 9, 2014

Yellow-legged gulls

Yellow-legged gull  Larus cachinnans Gawwija prima
Last Sunday I was at Marsaxlokk. I was sitting with my back to the open air market where thousands of Maltese and foreigners were walking from one stall to the other particularly those selling fish. While all this was going on several black-headed and yellow-legged gull were flying around the harbour looking for any scraps of food floating in the water. Sometimes flying very close to the shore.
The yellow-legged gull is a very large gull. It is Malta’s largest breeding bird. In Malta yellow-legged gulls are normally very wary and avoid getting too close to people but while I was watching and photographing them they came so close that with the naked eye one could clearly see the yellow legs, eye and beak as well as the red spot near the tip of the beak.
The red spot has an important function during the breeding season. When an adult bird approaches the nest the young birds start to peck at the red spot. This stimulates the adult birds to regurgitate its food.
At this time of the year the yellow-legged would have already started breeding. They breed in colonies, in Malta they prefer inaccessible places such as cliff faces and on top of the small islet of Filfla.
Thirty years ago shooting from boats was becoming very popular. Hundreds of Maltese hunters started to hunt from powerful dinghies to get the birds even before they reached land. They also used to patrol the cliffs to shoot at the birds there. The last pair of peregrine falcon fell victim to these hunters while the colonies of yellow-legged gulls were decimated.
It was only a few years ago, after hunting from sea craft started to be controlled, that the peregrine falcon started to breed again and the number of breeding yellow-legged gulls started to recover.

Strict bird protection does make a difference to bird populations. This is especially so in spring when the birds are preparing to breed.

The beetle that dwells in churches

Churchyard beetle - Blabs gigas - ħanfusa tal-kantina
The churchyard beetle is one of the larger beetles of the Maltese islands. Some individual specimens can grow up to 37mm long. It prefers to live in dark humid areas and can sometimes be found in basements, cellars, cave entrances and obviously churches.

In Maltese this common species is known as ħanfusa tal-kantina.

The front wings of most beetles are hardened and cover the abdomen and a pair of delicate wings. To fly, most beetles lift their front wings and unfurl the hind wings. The churchyard beetle cannot fly because its front wings are fused together and cannot be lifted.

Inability to fly could leave this species susceptible to many predators but it compensates for its inability to escape from danger by being able to secrete a pungent liquid from glands that are found in the joints of its limbs. Any bird or mammal trying to eat one soon learns to leave this disgusting insect alone.

Unpalatable insects such as the ladybird often have bright warning colours to make them easily recognisable. The churchyard beetle is jet black, probably, because it lives in dark places where colours would not be of any use.

When threatened the churchyard beetle can also change its posture to appear larger. It pushes its head against the ground and extends its hindlegs so as to tilt its body so that its wings face its enemy.

Several closely related species that lives in the Namib Desert on misty nights takes up a similar position to collect water which forms on theirs body. The body then trickles down their back to their head and mouth. 

The churchyard beetle belongs to a family of beetles known as the darkling beetles. A name they got because of their dark colour. The darkling is a large family with more than 20,000 members. In Malta about fifty species can be found a number of which are endemic to the Maltese islands. 

This article was published in The Times of Malta on 5 February 2014.




Sunday, March 2, 2014

The large carpenter bee

Large Carpenter bee - Xylocopa violacea - Bomblu iswed
The large carpenter bee is the most common species of carpenter bee in. It is the largest solitary bee in Europe. Carpenter bees can be found in most parts of the world. About 500 species have been identified but only three have been recorded in the Maltese islands. They get their name because nearly all species build their nests in burrows in dead wood. The large carpenter bee prefers to build it in the giant reeds.

In Maltese the large carpenter bee it is known as bomblu iswed.

This species of carpenter bee is found mainly in southern Europe. In recent years it started to expand its range northwards probably as a result of climate change which is resulting in warmer temperatures in most parts of Europe.
In 2006 it was recorded for the first time in Wales and since then it has been recorded regularly in various localities throughout England.

In Malta the large carpenter bee is not normally active during the winter months. Adults hibernate and emerge only when the days start to warm up. This year I saw it on several days in January. I even saw several couples mating at Is-Simar Nature Reserve and looking for suitable reeds in which to build their nest. This weekend’s cold windy weather must have sent them back to hibernation.

This species has large mandibles which it used to excavate into wood. It creates a tunnel and at its end it builds a number of separate cells which it stocks with nectar and pollen. The bee lays its eggs on the pollen and then leaves the nest to allow the larvae to develop on their own.

The large carpenter bee flies with a loud buzzing sound. To those who are not familiar with it, it may seem frightening but it is not aggressive at all and will attack only if provoked. The only person I know of who has been stung by this species accidentally put his hand in the sleeve of a jacket in which a large carpenter bee was resting.

This article was published in The Times of Malta on 29 January 2014




Yellow countryside carpet

Several species of plants with yellow flowers belonging to the mustard or cabbage family can be found growing in the Maltese countryside. Some such as the wild turnip are very common and grow in such profusion that they can carpet uncultivated fields in yellow.

One of them the wild turnip is known in Maltese as liftija.  This species flowers mainly from November to April. The plants found in Malta belong to a subspecies of a plant which exists in many subspecies and varieties. Many cultivated varieties of this species have been created by agronomist. These include the turnip, which in Maltese is known as nevew, and turnip rape from which a type of canola oil is made.

Rapini or broccoli rabe is a variety widely grown in Italy where it is known as cime di rapa. It originated in Italy but has been introduced by Italian immigrants to many parts of the world including the United States and Australia. It could probably grow very well in Malta during the winter months but as far as I know it has never been cultivated in the Maltese islands. Many kinds of vegetable which are grown in neighbouring countries would probably grow very well in the Maltese islands as well if only local farmers or vegetable gardeners would experiment with these varieties.

The wild turnip can be confused with the perennial wall rocket which is known in Maltese as ġargir isfar. This species flowers throughout the year although the number of plants in flower varies at different times of the year depending on rainfall. In summer the number of flowering plants is at a minimum while in September and October, after the first autumn rains, this species tends to be the most common yellow flowering plant.

The leaves of the perennial wall rocket are edible and can be used in salads. They have a strong flavour reminiscent of cress and rocket.

The two species, although very simila,r can be told about on close inspection by the shape of their leaves. The wild turnip has oval leaves with rounded ends while the perennial wall rocket has irregularly shaped leaves which give off a strong unpleasant smell when crushed.

This article was published in The Times of Malta on 22 January 2014





Communal roosting

White wagtail - Zakak Abjad - Montacilla alba
Communal roosting can be seen in several bird species. Every evening large numbers of birds congregate in a particular spot to sleep. Roosts can consist of birds of a single species or sometimes of mixed species. Most roosts are in trees especially in cities although some species such as gulls seek different habitats.

In Malta the best known communal roosters are the Spanish sparrow, the starling and the white wagtail. Spanish sparrows are resident and visit their roosts throughout the year although the number of birds visiting the roost changes with the season reaching a peak just after the breeding season when the population is at its highest.

Starlings and white wagtails winter in the Maltese islands. Both species are very common and can be seen throughout the winter even in urban areas. Starlings are noisy birds that often spend the day feeding on the ground in fields sometimes even very close to busy roads.

The white wagtail can be seen in built-up areas picking up insects and other small creatures from the ground. It is often very tame and can be approached closely before it flies away.   

Every year in early January a group of birdwatchers take up positions around the Valletta peninsula to count the number of white wagtails approaching the City to roost. Most of the white wagtails wintering in Malta spend the night in the large trees in front of the Law Courts and in St John’s Square in Valletta.
This year nearly 7,500 wagtails were counted approaching Valletta.

Communal roosting affords birds safety in numbers. A solitary bird sleeping in a tree stands little chance of avoiding being eaten by a predator but in a roost consisting of thousands of birds the chance of being eaten decreases by a factor of several thousands.

It is also believed that large numbers of birds roosting in a tree increase the temperature of their surroundings thus reducing the amount of energy they require to maintain their body temperature at an optimal level.

In some species communal roosting gives an opportunity to less experienced birds to follow older birds to good feeding sites thus saving time and energy.

This article was published in The Times of Malta on 15 January 2014


The parasite that thrives on living and dead trees

Inonotus tamaricis lives on tamarisk trees. In Maltese it is known lixka tal-bruk. Lixka is the Maltese name for shelf or bracket fungi. Lixka was also used for dried plants that were used to start a fire or light a pipe.

This species of fungus does not seem to have an English name so I will refer to it as the tamarisk bracket fungus which is a translation of its Maltese name. It grows on both dead and living trees and is considered as a pathogen because it can harm the trees it grows on. This is a species of southern Europe, North Africa and parts of the Middle East its range extending to Southern Asia and China.

Several species of bracket fungi or as they are sometimes known shelf fungi can be found in the Maltese islands. They are characterised by growing in the shape of a shelf or bracket attached to the bark of living or dead trees.

Bracket fungi are usually hard and tough. The actual fungus lives inside the tree. It is the fruiting body which we see growing on the bark. The fruiting bodies vary considerably in size ranging from tiny specimens to large perennial species that keep growing year after year.
Many bracket fungi are brownish, while some can be bright yellow, orange or red. They do not follow the well-known mushroom structure as they do not need a stalk to lift the fruiting body above the ground to release their spores.

Some species are saprophytes, that is, they live on dead organic matter. Others are parasites feeding on living wood eventually killing the tree in which they grow. These species sometimes cause considerable damage to the timber industry.

The tamarisk bracket fungus is easily seen but very few people notice them growing on the trunks of tamarisk trees that are found growing along many of Malta’s coastal promenades. 

This article was published in The Times of Malta on 8 January 2014.






The upright stonechat

Stonechat - Bicaqq tas-Silla - Saxicola torquata

The Maltese countryside in winter is enriched by several species of passerine birds that spend several months in the Mediterranean region to avoid the colder winter further north. Some species are also seen in urban areas and often visit gardens and rooftops even in areas in very built up localities.

In garigue areas, from late autumn to late winter one stands a very good chance of meeting the stonechat. This is a small bird that spends a lot of time keeping a lookout about a metre above the ground on top of a bush or some other perch.  From there they make regular sallies to the ground to pick up small creatures such as spiders and insects on which they feed.

The male and female have different plumage but both are easily recognised by their general shape and behaviour. They have a characteristic upright posture and often perch on the highest part of a bush. Most of the time both sexes make a clicking sound like two stones being hit together, hence this bird’s English name. Even the Maltese name, buċċaqq tax-xitwa is partly onomatopoeic. 

The male stonechat has a black head, back and tail. The wings are also black but have a large white patch on the wings. It also has a distinctive white collar which separates its head from its dark orange-red upper breast.

Females are less colourful. They are mostly brown with chestnut-buff underparts.

Stonechats are found breeding throughout most of Europe, Northwest Africa and the Middle East. Other species of stonechat are found in other parts of the world.

European stonechats are non-migratory although individuals that live in the north move south for the winter. A related species, the whinchat, breeds in Europe and western Asia and visits Malta on migration. It is called buċċaqq tas-silla. Silla is sulla, a spring crop and gives a good indication of the time when it is seen in the Maltese islands. 

This article was published in The Times of Malta on 1 January 2014