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.

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.

Plant with thick leaves in the shape of a heart

Ice plants belong to a large family of plants most of which are indigenous to southern Africa.

A few species can be found in Australia and the Central Pacific.

A number of species have been cultivated in Maltese gardens for many years and because of their ability to regenerate easily from pieces of broken stem have become naturalised in the Maltese countryside especially in the vicinity of gardens. .

The most common species are probably the heartleaf ice plant and the sword-leaved ice plant.

These two species can grow profusely and cover large areas of ground. They both produce large numbers of small red or pink flowers but it is very difficult to tell the two species apart.

They differ mainly in the shape of their leaves, one has heart-shaped and the other slightly pointed leaves but the leaves vary and sometimes it can be very difficult to tell the two species apart.

I have never met with a Maltese name for these two plants but they are so common in gardens and urban areas that I am sure that they do have a Maltese name.

Another well known species of ice plant is better known as the Hottentot fig.

In Maltese it is known as xuxet San Ġwann or perhaps more commonly as il-pjanta tas-swaba.

This species has thick succulent leaves and large pink flowers that can attract large numbers of bees and other insects in search of nectar and pollen.

In parts of the world with a climate similar to that of southern Africa notably parts of Australia, California and the Mediterranean this species has invaded large areas and has displaced indigenous species to the detriment of the areas’ biodiversity.

This has happened along parts of the Mediterranean coast where it now completely covers large tracts of land. Although these plants can be removed mechanically one must pay particular attention not to allow pieces of the plant in the soil as these can easily regenerate.

This article was published in The Times on 11.01.12

Nature Photography

Maltese wall lizard (Podarcis filfolensis)

I am often asked by readers of my articles about my nature photographs the questions more often than not revolve about the kind of equipment I use. 

My reply is always “nothing special’ a reply which is received with scepticism.

 I have a micro lens which I use most of the time but it is possible to take nature pictures even with the most basic camera, this is especially true nowadays as even the pocket digital cameras can be used for close-up photography. 

The picture of the lizard on a wall accompanying this article was shot without any special equipment. The most important thing is not the equipment but the ability to see pictures where many others do not.

Plants are often surrounded by other vegetation; animals often hide themselves in their surrounding. 

The most important skill is to learn to see pictures in the surrounding clutter. To do this you must learn to look and observe with all your senses a skill you develop with a lot of practice which you can only get by spending a lot of time in the countryside taking pictures or just looking and observing.

By spending some time looking at a particular patch of ground, a bush or even just a small plant you will start seeing things which you previously failed to notice. Insects and flowers seem to pop out of nowhere.

 I often lie down on the ground to get a good point of view and while in that position I start seeing one photograph after the other and I end up taking up a lot of pictures of different objects from one spot.

My advice to anybody who wants to take nature pictures is to get out there and start shooting. 

With digital cameras you can shoot hundreds and thousands of pictures without any extra cost. Spend as much time as possible in the countryside. I spend at least one whole morning every weekend in the countryside to ensure that I have good pictures for my articles.

This article was published in The Times on 20.10.10

Bees - 20,000 known species worldwide

Malta is justifiably well known for its honey. This natural product is produced by a domesticated species of bee. Although this is the best known species it is just one of at least 60 bee species that have been recorded in the Maltese islands.

Bees are flying insects closely related to wasps and ants. They are known for their role in pollination. 

There are nearly 20,000 known species of bees in the world with several still to be discovered. They are found in every continent except Antarctica and in every habitat where one finds insect-pollinated flowering plants. They are adapted for feeding on nectar and pollen which provide them with their energy and protein requirements. Pollen is used as food for larvae.

Bees play an important role in the pollination of flowering plants. When foraging they either gather nectar or pollen. While doing this they carry pollen from one flower to the other. Pollen is fine powder which contains the male sex cells of a plant. When the pollen reaches the female sex cells of a plant, a process known as pollination, fertilisation takes place. It is estimated that one third of the food consumed by man depends on insect pollination, mostly by bees especially the domesticated honey bee.

Most bees are fuzzy and have an electrostatic charge which attracts the pollen. The bees occasionally brush the pollen attached to their body and pack it into a structure that is usually found on their legs but sometimes on their abdomen. 

Some species of bees specialise on one species or a small number of related species of plants while others are opportunistic feeders and gather pollen from a large variety of plants.

Bees evolved from predatory wasps. When they first appeared there were already in existence insect pollinated plants which depended on other species of insects such as beetles for pollination but they have now become specialised pollinating agents much better at it than other insects such as flies and butterflies. 

This article was published in the Times on 23.02.10