PICTURED: An invasive species of mink attacks a nesting gannet. Photo credit: John Anderson. Retrieved from Birdlife.org.
Story at a glance…
While many of the UN’s 2020 Aichi Conservation Targets were missed, controlling invasive species was more or less achieved.
It was achieved through 800 eradications of invasive plant and animal species – often through extermination.
The vast majority of these successes were found on islands, where specialized animals are at a special risk of invasive species pressure.
In 2010, the UN Convention on Biodiversity released their 2020 Aichi Conservation Targets which aimed to create a world secure and improving for biodiversity by the end of the decade.
Of the 20 targets, many of the bureaucratic goals have been achieved, however the overall measure has been a failure in many way. Most nations failed to improve or even address the most serious of the objectives such as the elimination of harmful government subsidies and unsustainable fishing practices, halting species and habitat loss, and minimizing the loss of climate-sensitive ecosystems like reefs.
On the other hand, target #9, which is the prevention and elimination of alien and invasive species from sensitive ecosystems has been a resounding success, and involves one of the great conservation success stories of the decade.
Its success goes often untold by newspapers and journals as it involves mass-eradication of species, which many compassionate wildlife activists might find at least distasteful, and at worst barbaric.
#9 Prevention of Alien Species
“By 2020, invasive alien species and pathways are identified and prioritized, priority species are controlled or eradicated and measures are in place to manage pathways to prevent their introduction and establishment,” reads the explanation of Aichi target 9 on the recent Global Biodiversity Outlook, GBO version 5, produced this September at the climax of the project.
Stories of invasive species are famous on islands like the Galapagos, New Zealand, Madagascar, and Hawai’i, as well as the continent of Australia. Here, where isolation is greatest, animals can evolve in extremely unique ways.
Invasive animals tend to be successful animals; with creatures like rats, foxes, cats, goats, hogs, and more, being extremely adaptable and capable of living in almost any environment. Australia is home to the world’s largest concentrations of marsupials, yet the violence of the domestic cat, the fox, and others has been too much for many of them, and several species like the desert bandicoot have gone extinct since Europeans arrived on the continent.
Over the last decade, Aichi target 9 has seen the greatest success come in the form of the implementation of an infrastructure with which relevant authorities can train, monitor, prioritize, and respond to invasive wildlife species and the ways in which they arrive where they shouldn’t be.
“Information and data about the occurrence and distribution of invasive alien species is increasingly available and accessible, with multiple organizations collaborating to help link up previously disconnected data sources.,” reads the GBO report.
Unfortunately it also notes a comprehensive study done in 2017 that showed there were no signs of a decrease in the rate of alien animal invasions, while on the other hand, 75% of party nations say they are making progress towards the Aichi-stated target — 26% of whom will achieve or exceed it.
War in the Pacific
This infrastructure and data sharing, especially regarding the consequences of allowing invasive species to gain a foothold in the ecosystem, has led to more than 800 successful eradications of invasive mammals on 181 different islands since the year 2000.
The GBO estimates this has had positive benefits for an estimated 236 native terrestrial species.
200 of these eradications have occurred during the Aichi decade of 2010-2020, and have benefited more than 100 highly threatened species of birds, mammals and reptiles, including the island fox and Seychelles magpie-robin.
“Recent analysis has also identified 107 priority islands where eradication of invasive mammals could feasibly start in the near future, improving the survival prospects for 80 highly-threatened vertebrates, thus making a significant contribution to the fight against global extinctions,” reads the GBO.
If this goal was obtained, then it along with these eradications alone would more than double the amount of species saved from extinction by traditional conservation means like government legislation, captive breeding and reintroduction programs, and habitat protection, that was recently calculated as about 48 by a team of scientists from Newcastle University and Birdlife International.
Stories from the trenches
Antigua and Barbuda
— Goats and black rats were introduced to Redonda Island in the 1930s. These invasive species have had significant negative impacts on the ecosystem, and on several species of birds and reptiles which, as a result, are listed as Critically Endangered.
The Redonda Restoration Programme addressed the problem by removing the goats and rats from the island. As a result, trees and grasses have been able to grow, stabilizing the island’s soils and reducing runoff which was previously damaging surrounding coral ecosystems. The lizard population on Redonda has tripled following the eradication of goats and rats. Efforts are under way to have Redonda declared a protected area.
Republic of the Congo
Invasive aquatic plants, such as water hyacinth, water lettuce and giant salvinia have a range of negative impacts on water systems by outcompeting or displacing endemic species for space, light and nutrients.
In order to control these invasive aquatic plants, three species of weevils are being used as biocontrol agents. As a result of these efforts some waterways in the Kouilou and Likouala regions have been restored.
Once again, goats take center stage in a drama on Guadalupe Island, where between 2003 and 2006, the population of invasive goats clambering over the rugged and beautiful terrain of the island, gobbling up all the native plant species and outcompeting local herbivores, was eradicated via helicopter.
Now thousands of endemic pine and sage seedlings can be found growing on the island again.
Many developing Pacific Island states are vulnerable to the impacts of alien invasions, and according to Battling Invasive Species in the Pacific, an executive summary by the Secretariat of the Pacific Regional Environmental Programme, there are 2,200 single-country endemic-species in Pacific ecosystems, 45% of which are at risk of extinction — particularly from invasive species.
The Secretariat thus prepared a uniform Pacific-wide strategy guide for best practices of managing invasive species, and included 100 activities over 10 island states over 5 years.
There isn’t a lot to be cheerful about when reading the summary of the 5th Global Biodiversity Outlook, but islands across the world’s seas are doing very well, and if controlling the spread and moments of arrival of invasive species can be obtained, the legacy of Aichi may not be ‘the failure that was’ but rather ‘hope for the future’.