Biological Invasions in the Forests: An overview T.V.Sajeev Scientist Forest Health Kerala Forest Research Institute

Invasive species- what are they? Plants, animals and microbes non-native to a specific ecosystem whose introduction will cause economic and ecological harm and/or harm to human health

Mikania micrantha

Theory of invasion The enemy release hypothesis Novel weapon hypothesis Evolution of increased competitive ability hypothesis

A widespread and significant component of human-caused global environmental change- the least reversible. One of the most serious environmental challenges we face today Invasive plants invade ecosystems, spread quickly, displace native plants, monopolize resources, upset ecological equilibrium, finally leading to formation of a large monoculture of invasive plants

Biological attributes contributing to the success of Invasive Species include Phenotypic plasticity Dispersal benefits Widespread geographic range Vegetative reproduction Fire tolerance Better competitive, resource capture and utilization abilities than native plants Allelopathy

Chromolaena odorata

Introduction of invasive species Inadvertent – unintentional hitchhiking through international trade and travel (ships, planes, shipping containers, packing materials, unprocessed logs, fruits, seeds – a by product of global trade and travel)

Parthenium hysterophorus

Intentional - relate to human interest in nurturing species that are helpful to him Agricultural, forestry, ornamental species, dietary needs There is a third kind- species imported for a limited purpose which then escape

Why invasive species are a problem? Economic damage Costs 1.4 trillion dollars globally – 5% of global economy Overall losses in many countries – over 1% of GDP Costs – 15 billion dollars to China 136 b dollars to the US Approx. 200 b dollars annually to the Asia- Pacific region

Other harmful effects Ecosystem alters ecosystem processes, hydrology, primary productivity, decomposition, nutrient cycling, fire regimes, damage through broadcast of pesticides and herbicides, affect closely related indigenous species by hybradization, changes soil structure and profile Human health and well being allergic responses, spread of diseases

Aesthetics death of vegetation, smothering of native plants Native biodiversity population decline through altering of ecosystem processes, allelopathy Also, invasive species interact with other global changes like land use change

Eichornia crassipes

Impact on Forests, agricultural land, plantations, grasslands, arid lands, oceans, lakes, streams, water quality, fisheries, animal husbandry, roads, water ways, recreational sites and wild life populations Invasion of birds and fishes not as frequent as invasion by plants

Pueraria montana

The Earth is essentially a loaded gun of exotic species problems We transport species freely across barriers because we forget that the ecological and co-evolutionary setting of plants is a key to their identity, population traits and ability to invade.

Impatiens glandulifera

What shall we do? Awareness raising convincing our colleagues, students, NGO’s and the public wide publicity- media, exhibiting posters at ports local bodies allocating funds to conserve biodiversity, local life style and tourism Develop better policies and legal frame work New Zealand Biosecurity Act Australian, US and the Canadian Policies

India is a signatory of both the Convention of Biological diversity and World Trade Organization Article 8 h of the CBD emphasizes on prevention of introduction of Invasive alien species

Giant african snail (Achatina fulica)

There is no cohesive policy to deal with invasive species in India MoEF is still in the process of developing policies and strategies for their management Early detection and rapid response Pest risk assessments, surveys International and regional collaborations – training and sharing of expertise

Early detection and prevention are the most effective and cost efficient strategies to combat invasive species Direct control of existing populations are rarely successful unless combined with cultural practices Ecological restoration of the weed free habitat is the key to successful eradiation of invasive plants

Mimosa invisa

Protected area IAS programs Assess invasive species threats (existing and potential) Prevent new invasions and the spread of established invasives Control high priority IAS in high priority places Restore / rehabilitate native species and communities in high priority places

What should be included in a Protected area IAS assessment? There are several methods for evaluating the overall threat of IAS for a Protected Area or a Protected Area system Good ones should clearly state: The exact area covered. The conservation goals (values to be protected including target species and communities) and management objectives The IAS which are currently present / absent and mapped locations (if possible); The IAS which have impacts on conservation goals and management objectives: The important pathways/ vectors for IAS entry and dispersal. Prediction of future spread and impact of IAS if not controlled. Capacity of existing staff and resources to adequately prevent and control IAS and the damages they cause

Asia-Pacific Forest Invasive Species Network (www.apfisn.net) A cooperative alliance of 33 member countries in the Asia-Pacific region Goal- cooperation among the member countries that helps to detect and prevent incursions of invasive species and monitor, eradicate or control

Blue gum chalcid (Leptocybe invasa)

Objectives Awareness raising Information exchange Capacity building Develop action plans in combating invasive species through regional collaboration

Thanks