INVASIVE ALIEN SPECIES 

Invasive alien species (IAS), also known simply as invasive species, are non-native organisms that, when introduced to a new environment, can cause harm to the native ecosystem, economy, or human health. These species often thrive in their new environment due to the absence of natural predators or competitors, leading to rapid population growth and ecological disruption.

The key points about invasive alien species

Invasive species can be introduced intentionally or accidentally by humans. Intentional introductions often occur for agricultural, horticultural, or ornamental purposes, while accidental introductions can happen through global trade, transport, or tourism.

• Invasive species can outcompete native species for resources such as food, water, and habitat, leading to declines in native populations. They may also alter ecosystem processes such as nutrient cycling and fire regimes, leading to long-term ecological changes.
• Invasive species can have significant economic impacts by damaging crops, forests, fisheries, and infrastructure. Control and management efforts to mitigate these impacts can be costly and time-consuming.
• Some invasive species can pose direct threats to human health by transmitting diseases or causing allergic reactions. For example, certain invasive plants may produce pollen that triggers allergies in sensitive individuals.
• The rise of global trade and travel has facilitated the spread of invasive species, leading to an increase in their prevalence and distribution worldwide. Climate change may also exacerbate the problem by creating new habitats suitable for invasive species.
• Efforts to manage and control invasive species include prevention, early detection and rapid response, eradication, and long-term control measures. These efforts often require collaboration between government agencies, researchers, conservation organisations, and the public.

Invasive alien species (IAS) can impact native species in various ways, often leading to significant ecological disruption.

The primary ways in which IAS affect native species

•  Invasive species can compete with native species for essential resources such as food, water, space, and sunlight. They may have competitive advantages, such as rapid reproduction rates or lack of natural predators, which allow them to outcompete native species for resources.
•  Invasive species may prey on or consume native species, leading to declines in native populations. For example, invasive predators can decimate native prey populations, while invasive herbivores can overgraze native vegetation, altering habitat structure and reducing food availability for native species.
• Invasive species can modify habitats through activities such as burrowing, nesting, or altering vegetation composition. These habitat alterations can disrupt native species' ability to find suitable nesting sites, forage for food, or carry out other essential behaviours.
• Some invasive species can introduce new diseases or parasites to native populations, which may lack immunity to these pathogens. This can lead to disease outbreaks and population declines in native species. For example, the chytrid fungus, introduced by the global amphibian trade, has caused widespread declines and extinctions among native amphibian species.
• Hybridization between invasive and native species can occur when they come into contact. This can lead to genetic introgression, where genes from the invasive species are incorporated into native populations, potentially altering their genetic diversity and fitness.
• Invasive species can disrupt ecological relationships and food webs by altering species interactions. For example, if an invasive species outcompetes a native species for a shared prey species, it can indirectly impact other species that rely on that prey for food.

4. About the Convention on Biological Diversity (CBD)

The Convention on Biological Diversity (CBD) is an international treaty aimed at conserving biodiversity, promoting sustainable use of biological resources, and ensuring the fair and equitable sharing of benefits derived from genetic resources. It was opened for signature at the Earth Summit in Rio de Janeiro, Brazil, in 1992, and entered into force on December 29, 1993. The CBD has three main objectives:

1. The CBD aims to conserve biological diversity, including ecosystems, species, and genetic diversity, through the establishment and management of protected areas, the conservation of threatened species, and the restoration of degraded ecosystems.
2. The CBD promotes the sustainable use of biological resources to meet current and future human needs while ensuring the long-term health and resilience of ecosystems. This includes activities such as sustainable forestry, fisheries management, and sustainable agriculture practices.
3. The CBD seeks to ensure the fair and equitable sharing of benefits derived from the utilization of genetic resources, including the sharing of monetary and non-monetary benefits with countries and communities that are the custodians of those resources.

The CBD operates through meetings of the Conference of the Parties (COP), which are held regularly to review progress, negotiate agreements, and make decisions on matters related to the implementation of the convention. The COP has adopted several protocols and agreements to further the objectives of the CBD, including the Cartagena Protocol on Biosafety and the Nagoya Protocol on Access and Benefit-sharing.

5. What are invasive species?

Invasive species are organisms that are introduced, either intentionally or unintentionally, into a new environment where they are not native. These introduced species can cause harm to the environment, economy, or even human health.

Here's a breakdown of what makes a species invasive:

• Non-native: They come from a different region and weren't originally part of the local ecosystem.
• Harmful: They cause ecological or economic damage in their new environment. This can include things like outcompeting native species for resources, preying on them, or introducing diseases.

Not all introduced species become invasive. Some introduced species can even be beneficial, like honeybees which are crucial for pollinating crops. However, invasive species become problematic because they lack the natural controls (predators, diseases) they faced in their original habitat. This allows them to reproduce rapidly and disrupt the balance of the new ecosystem.

8. What is IPBES?

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is an independent intergovernmental body established to assess the state of biodiversity, ecosystems, and the contributions they provide to human well-being. IPBES was established in 2012 and is headquartered in Bonn, Germany.

Key functions and objectives of IPBES include

• IPBES conducts regular assessments of the state of biodiversity and ecosystem services at the global, regional, and national levels. These assessments involve synthesizing scientific knowledge from experts around the world and providing policymakers with information to support decision-making.
• IPBES provides policymakers with evidence-based assessments, tools, and policy recommendations to promote the conservation and sustainable use of biodiversity and ecosystems. This includes identifying policy options and best practices for addressing the drivers of biodiversity loss and ecosystem degradation.
• IPBES supports capacity-building efforts to enhance the ability of countries and stakeholders to assess, manage, and conserve biodiversity and ecosystem services effectively. This includes providing training, technical support, and guidance on assessment methodologies and tools.
• IPBES facilitates knowledge exchange and collaboration among scientists, policymakers, practitioners, indigenous and local communities, and other stakeholders involved in biodiversity and ecosystem management. This includes organizing workshops, conferences, and other events to share information and best practices.
• IPBES promotes policy-relevant research on biodiversity and ecosystem services to address knowledge gaps and support informed decision-making. This includes identifying research priorities and coordinating research efforts across disciplines and sectors.

IPBES operates through a multistakeholder governance structure involving governments, scientists, indigenous and local communities, non-governmental organisations, and other stakeholders. It conducts its work through a series of plenary sessions, expert groups, and technical support units focused on specific thematic areas and regions.

9. The Way Forward

By taking a proactive and collaborative approach to managing invasive species like chital on Ross Island, it's possible to mitigate their negative impacts on native biodiversity and ecosystems while promoting sustainable conservation practices.

Source: The Indian Express