Invasive Alien Species (IAS) are plants, animals, pathogens and other organisms that are non-native to an ecosystem, and which may cause economic or environmental harm or adversely affect human health. In particular, they impact adversely upon biodiversity, including decline or elimination of native species - through competition, predation, or transmission of pathogens - and the disruption of local ecosystems and ecosystem functions (CBD, 2009)
Invasive alien species, introduced and/or spread outside their natural habitats, have affected native biodiversity in almost every ecosystem type on earth and are one of the greatest threats to biodiversity. Since the 17th century, invasive alien species have contributed to nearly 40% of all animal extinctions for which the cause is known (CBD, 2006). IAS are found in nearly all major taxonomic groups of organisms. Invasive species include viruses, fungi, algae, mosses, ferns, higher plants, invertebrates, fish, amphibians, reptiles, birds and mammals.
Invasive alien species, introduced and/or spread outside their natural habitats, have affected native biodiversity in almost every ecosystem type on earth and are one of the greatest threats to biodiversity. Since the 17th century, invasive alien species have contributed to nearly 40% of all animal extinctions for which the cause is known (CBD, 2006). IAS are found in nearly all major taxonomic groups of organisms. Invasive species include viruses, fungi, algae, mosses, ferns, higher plants, invertebrates, fish, amphibians, reptiles, birds and mammals.
SDG 15 has 12 targets that seek to prevent further deterioration, conserve and protect biodiversity and work towards restoration of past damages. One of these damages is due to Invasive Alien Species (IAS) that has been recognized as one of the targets under this Goal with action by 2020:
15.8 By 2020, introduce measures to prevent the introduction and significantly reduce the impact of invasive alien species on land and water ecosystems and control or eradicate the priority species
As a ‘slow pace’ threat, many communities in Uganda and elsewhere in the world are faced with the economic social and ecological impact of IAS. But current efforts to address this challenge is not commensurate with the efforts needed.
The spread of invasive alien species (IAS) is now recognized as one of the greatest threats to the ecological and economic well-being of the planet. It is creating complex and far-reaching challenges that threaten both the natural biological riches of the earth and the well-being of our people. These species are causing enormous damage to biodiversity and the valuable natural agricultural systems upon which we depend. Direct and indirect health effects are increasingly serious and the damage to native biodiversity is often irreversible. The effects may be exacerbated by global change and chemical and physical disturbance to species and their habitats.
Continuing globalization, with increasing trade, travel, and transport of goods across borders, has brought tremendous benefits to many people. It has, however, also facilitated the spread of IAS, with increasing negative impacts. The problem is global in scope and requires international cooperation to supplement the actions of governments; the private sector and organizations at national and local levels.
Economic costs alone run into hundreds of billions of U.S. dollars per year (GISP, 2004). Other serious impacts are on human health, native biodiversity and ecosystems.This damage is aggravated by climate change, pollution, habitat loss and human-induced disturbance
According to IUCN’s Invasive Species Specialist Group, many species introduced into new environments are unable to survive in their new surroundings. However, a percentage of these species are able to expand the area they infest and negatively impact the economy, human health or ecology of a region and are termed invasive. Habitat alteration and invasive species impacts have been the major cause of species extinctions over the past few hundred years, increasing the rate of extinction by about 1,000 percent.
Although in the past, many of these losses have gone unrecorded, today, there is an increasing realization of the ecological costs of biological invasion in terms of irretrievable loss of native biodiversity and degradation of ecosystem functioning. While the underlying causes of invasive species threats are significant and global in nature, these threats can be effectively dealt with through collaborative efforts at regional and local levels, especially through prevention, early detection and rapid response.
To make matters worse, a major challenge now is to understand the influence of climate change on the complex interactions and impacts of invasive species on natural and human-altered ecosystems.
15.8 By 2020, introduce measures to prevent the introduction and significantly reduce the impact of invasive alien species on land and water ecosystems and control or eradicate the priority species
As a ‘slow pace’ threat, many communities in Uganda and elsewhere in the world are faced with the economic social and ecological impact of IAS. But current efforts to address this challenge is not commensurate with the efforts needed.
The spread of invasive alien species (IAS) is now recognized as one of the greatest threats to the ecological and economic well-being of the planet. It is creating complex and far-reaching challenges that threaten both the natural biological riches of the earth and the well-being of our people. These species are causing enormous damage to biodiversity and the valuable natural agricultural systems upon which we depend. Direct and indirect health effects are increasingly serious and the damage to native biodiversity is often irreversible. The effects may be exacerbated by global change and chemical and physical disturbance to species and their habitats.
Continuing globalization, with increasing trade, travel, and transport of goods across borders, has brought tremendous benefits to many people. It has, however, also facilitated the spread of IAS, with increasing negative impacts. The problem is global in scope and requires international cooperation to supplement the actions of governments; the private sector and organizations at national and local levels.
Economic costs alone run into hundreds of billions of U.S. dollars per year (GISP, 2004). Other serious impacts are on human health, native biodiversity and ecosystems.This damage is aggravated by climate change, pollution, habitat loss and human-induced disturbance
According to IUCN’s Invasive Species Specialist Group, many species introduced into new environments are unable to survive in their new surroundings. However, a percentage of these species are able to expand the area they infest and negatively impact the economy, human health or ecology of a region and are termed invasive. Habitat alteration and invasive species impacts have been the major cause of species extinctions over the past few hundred years, increasing the rate of extinction by about 1,000 percent.
Although in the past, many of these losses have gone unrecorded, today, there is an increasing realization of the ecological costs of biological invasion in terms of irretrievable loss of native biodiversity and degradation of ecosystem functioning. While the underlying causes of invasive species threats are significant and global in nature, these threats can be effectively dealt with through collaborative efforts at regional and local levels, especially through prevention, early detection and rapid response.
To make matters worse, a major challenge now is to understand the influence of climate change on the complex interactions and impacts of invasive species on natural and human-altered ecosystems.
IAS situation and current efforts to address it in Uganda
Uganda is among the top ten countries in the world in terms of animal and plant diversity, and specifically, diversity of mammalian species. The major natural ecosystems are: forests, woodlands / savannahs, wetlands, and open water and mountain ecosystems.
In Uganda the IAS is a threat to the conservation of biodiversity through their proliferation and spread, displacing or killing native flora and fauna and affecting ecosystem services, including water and nutrient cycles and food chains
A preliminary list of IAS for Uganda (NARO 2002) includes species such as Lantana camara, Broussonetia papyrifera, Mimosa pigra and Senna spp. whose threat on native species has increased considerably. For example, Senna spectabilis has invaded over 1,000 ha of the Budongo Forest Reserve and vast areas of the Matiri Forest Reserve (Kyenjojo District) while Broussonetia papyrifera has covered vast areas of the Mabira Forest Reserve. Control strategies for these species are still being investigated (NARO, 2009).
Noting that introduction of alien species ruins Uganda’s biodiversity, the National Biodiversity Strategy ad Actin Plan (NBSAPI) developed in 2002 (framework for implementing its obligations under the Convention of Biodiversity as well as the setting of conservation priorities, channeling of investments and building of the necessary capacity for the conservation and sustainable use of biodiversity in the country) had an initial implementation period of 10 years with a major review after 10 years. Uganda now has NBSAPII after the review
The priority areas for NBSAPII are also in line with National Vision 2040, the Sustainable Development Goals (SDGs) and the National Development Plan II (NDP II). One of them is managing pollution and IAS.
Uganda’s National Biodiversity Strategy and Action Plan II seeks to address IAS among other challenges. To date Uganda also has put in place a Central node/Clearing House Mechanism (CHM) to facilitate information sharing among institutions involved in biodiversity conservation that is housed at National Environment Management Authority (NEMA Uganda).
In addition to this there are other specialized institutions that are contributing to addressing the IAS challenge in Uganda since NBSAPI. The follow-up NBSAP II has a goal is “to enhance biodiversity conservation, management and sustainable utilisation and fair sharing of its benefits by 2025” and 7 Strategic Objectives each with an Action Plan stretching from 2015 to 2025. NBSAPII also has national biodiversity targets that provide a framework for measuring progress in the implementation of NBSAPII and will be implemented by target champions (different actors including CSOs and communities).
Strategic Objective 3 of the NBSAPII is to put in place measures to reduce and manage negative impacts on biodiversity with various strategies including putting in place eradication and control measures for alien invasive species
Uganda is among the top ten countries in the world in terms of animal and plant diversity, and specifically, diversity of mammalian species. The major natural ecosystems are: forests, woodlands / savannahs, wetlands, and open water and mountain ecosystems.
In Uganda the IAS is a threat to the conservation of biodiversity through their proliferation and spread, displacing or killing native flora and fauna and affecting ecosystem services, including water and nutrient cycles and food chains
A preliminary list of IAS for Uganda (NARO 2002) includes species such as Lantana camara, Broussonetia papyrifera, Mimosa pigra and Senna spp. whose threat on native species has increased considerably. For example, Senna spectabilis has invaded over 1,000 ha of the Budongo Forest Reserve and vast areas of the Matiri Forest Reserve (Kyenjojo District) while Broussonetia papyrifera has covered vast areas of the Mabira Forest Reserve. Control strategies for these species are still being investigated (NARO, 2009).
Noting that introduction of alien species ruins Uganda’s biodiversity, the National Biodiversity Strategy ad Actin Plan (NBSAPI) developed in 2002 (framework for implementing its obligations under the Convention of Biodiversity as well as the setting of conservation priorities, channeling of investments and building of the necessary capacity for the conservation and sustainable use of biodiversity in the country) had an initial implementation period of 10 years with a major review after 10 years. Uganda now has NBSAPII after the review
The priority areas for NBSAPII are also in line with National Vision 2040, the Sustainable Development Goals (SDGs) and the National Development Plan II (NDP II). One of them is managing pollution and IAS.
Uganda’s National Biodiversity Strategy and Action Plan II seeks to address IAS among other challenges. To date Uganda also has put in place a Central node/Clearing House Mechanism (CHM) to facilitate information sharing among institutions involved in biodiversity conservation that is housed at National Environment Management Authority (NEMA Uganda).
In addition to this there are other specialized institutions that are contributing to addressing the IAS challenge in Uganda since NBSAPI. The follow-up NBSAP II has a goal is “to enhance biodiversity conservation, management and sustainable utilisation and fair sharing of its benefits by 2025” and 7 Strategic Objectives each with an Action Plan stretching from 2015 to 2025. NBSAPII also has national biodiversity targets that provide a framework for measuring progress in the implementation of NBSAPII and will be implemented by target champions (different actors including CSOs and communities).
Strategic Objective 3 of the NBSAPII is to put in place measures to reduce and manage negative impacts on biodiversity with various strategies including putting in place eradication and control measures for alien invasive species
Key issues / concerns about Target 15.8 of SDG15 in Uganda
The key obstacles to NBSAPI implementation largely remain unsolved today. These include:
The key obstacles to NBSAPI implementation largely remain unsolved today. These include:
- Inadequate financial resources for implementing planned activities; inadequate awareness of NBSAPI; Inadequate human and infrastructure capacity in certain fields of biodiversity conservation such as taxonomy and characterization of germplasm in the National Gene Bank; Inadequate managerial and technical capacity at the District and lower local Government levels for implementation of NBSAPI.
- Several tree and other plant species were introduced during the colonial period for example the eucalyptus, which have adapted quite well, colonizing and replacing indigenous species
- The threat to Plant Genetic Resources arising from loss of other indigenous species found in cultivated areas (e.g. Crotolaria jaburnifloria, Thumbergia alarta and Eluophia streptopetala (internationally protected), as well as increasing problems of invasive crop weeds (e.g. parasitic Striga, Couch grass and Lantana camara; This affects crop productivity and farmer’s incomes as these weeds lower crop yields and increases susceptibility of farmlands to increased pest and disease attacks
- Uganda’s lakes and rivers might be the ecosystems most affected by the introduction of exotic species and the consequent ecological changes in species and community composition. For example, invasive weeds like the water hyacinth is one of the primary threats to freshwater species in the Lake Victoria basin, where an estimated 76% of the region’s endemic freshwater species is threatened (IUCN, 2018). The introduction of Nile perch in Lake Victoria has caused an economic boom, but driving at least 200 species including caused cichlids, a native fish to extinction in the process (GISP, 2004).
- There is some concern that indigenous animal breeds are being undermined, as land becomes scarcer and the demand for high-yielding breeds increases as the rush to increase productivity overshadows the need to conserve these breeds.
Challenges
- The present tree planting activities of Uganda's National Forestry Authority (NFA), donors and other actors are focused on introduced species (Eucalyptus spp., Pinus spp. and Grevillea robusta). This could threaten the survival of native species if there are no guidelines for private tree planting
- There is still low level of awareness about IAS and its impact. For example, dodder (Cuscuta species) that afflicts many crops, ornamental and native plants virtually decimating them, is still considered an ornamental species in both urban and rural areas including amongst Kampala’s elites.
- There is low level of funding for biodiversity conservation activities (Environment and Natural Resources sector generally). With heavy expectation from donors to supplement proposed by Government allocation represent a substantive source of funding for the NBSAPII action plan. However, impact of invasive weeds needs a more predictable funding pattern, requiring fast response (water hyacinth infestation, etc).
- The present policies and legislation for management of terrestrial biodiversity on private land is inadequate, making actions to address IAS difficult to implement
- Similarly, the existing land tenure systems of land holdings, leasehold and customary holdings offer little incentive for protection and management of biodiversity on private land (for example maintenance of habitats and species are at the mercy of individual land owners)
Recommendations
- Support domestication of useful plants and animals, designing strategies and plans to incentivize protect threatened species on private lands, continuous collection and inventory of useful plant and animal species, designing and maintaining a comprehensive database inclusive of species diversity
- Building awareness in communities (indigenous and traditional knowledge and techniques toward the protection and safeguarding of Plant and Animal Genetic Resources) through seed banks, Indigenous Foods Festivals, IAS Campaigns in ‘hotspot’ areas, etc.
- More research on control strategies for IAS to be investigated
- NEMA Uganda should popularize and mobilize resources to implement Uganda’s NBSAPII (2015 – 25) amongst the different actors (target champions) especially the District Local Government, Local Communities, NGOs and Private sector.
- As part of the East African Community policy and legal processes, prevent new IAS invasions by improving their screening and surveillance procedures at border points
