12 July 2009
International Day for Biological Diversity
Alfred E. Baldacchino
Every year, the International Day for Biological Diversity is celebrated (internationally, but not in Malta) on 22 May, as declared by the United Nations for the promotion of biodiversity issues. This year, the International Day for Biological Diversity appropriately chose as its theme the issue of the introduction of invasive alien species (IAS). The International Union for Conservation of Nature and Natural Resources (IUCN) defines invasive alien species “as an alien species which becomes established in natural or semi natural ecosystems or habitat, an agent of change, and threatens native biological diversity. These invasive are widely distributed in all kinds of ecosystems throughout the world, and include all categories of living organisms.” Plants, mammals and insects are the most common types of invasive alien species in terrestrial environments. The threat to biodiversity due to IAS is considered second only to that of destruction of natural habitats.
Invasive alien species
Invasive alien species have fearsome negative impacts. They:
• are one of the greatest threats to biodiversity, and to the ecological and economic well-being of society and the planet;
• are capable of establishing, invading and outcompeting native species leading some to extinction;
• can cause changes which can be irreversible; • can act as vectors for new diseases, alter ecosystem processes, change biodiversity, disrupt cultural landscapes;
• decimate crops;
• take lifts in ballast water and on ships’ hulls, possibly upsetting ocean food chains;
• worsen human health problems, like hay fever;
• some newly introduced plant pests even cause famines, claiming the lives of millions of people and displacing millions of others;
• feed on, hybridise with, parasites and outcompete native species.
Invasive alien species are active on a global scale. With the everincreasing global markets and the rise in global trade, travel and tourism and the concept of the free movement of goods, as in the European Union, IAS have every chance of further extending their range and numbers in this century.
The economical damage and control costs of introduced IAS are indeed fearsome. On a global level, the yearly costs are estimated at $1.4 trillion. In Britain, combating IAS amounts to £2 billion a year; 60 per cent of invasive plants in the UK are garden escapees. Preliminary estimates indicate that the monetary cost of IAS in Europe amounts to at least e10 billion per year, and yet almost nothing is known of the impacts, as yet, for 90 per cent of the IAS. The marine environment is not spared either, and it is estimated that overall annual European expenditure to combat IAS amounts to e8.18 million. One of the greatest problems with regard to the control of IAS is that too many governments ignore such alien species, or procrastinate sine die until the effects are visible and can no longer be swept under the carpet.
The European Union
The European Commission recently became more concerned about the impact of IAS, many of which have bene-fited from the free movement of goods concept. These are having such a negative impact on the Community and threatening European biodiversity, that a number of policy options for developing a strategy to deal with IAS have been drafted. These are aimed at a coordinated approach and measures to be put in place immediately, and include a Europe-wide early warning system for reporting IAS. Such a harmonised approach is conspicuous by its absence. European Environment Commissioner Stavros Dimas said: “Invasive species are a major threat to biodiversity. Halting the loss of biodiversity in the EU will not be possible without tackling the problem of these unwelcome visitors. Given the way that these quickly become established and spread, measures taken by one member state can have no effect if neighbouring countries fail to take action or respond in an uncoordinated manner. The ecological, economic and social consequences of the spread of invasive species for EU countries are serious and need a harmonised response.” The journal Science1 recently published a paper that suggests that legislation is not enough to tackle IAS. It also points out that Europe lacks appropriate governance and institutional coordination across member states to tackle the IAS invasion effectively.
The Maltese scenario
In recent years, the number of IAS in the Maltese Islands has been increasing alarmingly. The most popular seems to be the red palm weevil, which, since its introduction, has devastated at least 300 mature adult palm trees. How did Malta commemorate International Day for Biological Diversity on 22 May, with the present theme of controlling Invasive Alien Species? The only reference to the subject was a press release from the Department of Information dated 25 May, in which the ministry responsible for agriculture informed the public that another introduced alien species – the tomato leaf miner – had, since April 2009, set up house in the Maltese Islands. It also informed the general public about the insecticides to use to eliminate this IAS. But worse still is the fact that when some species are declared as IAS locally, or on a European scale, these are still locally traded. To add insult to injury, invasive alien plants are planted by a government contractor, who is paid out of public funds. A case in point is the Hottentot Fig, a flat evergreen South African succulent plant with large magenta or yellow flowers, which spreads along cliffs, and spreads aggressively once it becomes established in the environment. All one has to do is take a look at the planted specimens on the roundabout leading to Malta International Airport, and at those established invasive specimens along the cliff faces on the southern coasts of the island. The Hottentot Fig is one of the IAS on the elimination target list of some EU member states, and is also declared as such by Mepa.
Besides a strong pair of hands and a virtual environmental column, a clear official vision, an iron will and a Minister for the Environment are urgently needed to give the environment the much needed boost on the lines of the obligations outlined in the EU environmental acquis. The aliens are here, there and everywhere, and in strong numbers.