The Equation of Invasion Biological Invasion and the Human Measure Against it
(2023) BION02 20221Degree Projects in Biology
- Abstract
- Biological invasion is one of the main drivers of species extinctions. Therefore, measures are implemented to reduce the abundance of the invading species with the goal to mitigate its impact. These measures often lead to high labour and economic expenditures yet their effectiveness are often uncertain. To evaluate and thereby improve the mitigation of invasions, it is essential to understand the invasion process and the underlying mechanisms of the removal effort of the invading species. In this study, I use a trait and niche- based theoretical approach to study such processes and mechanisms. I simulate invasion into a residential community followed by simulated removal of the invading species. The invasion process reveals that the impact... (More)
- Biological invasion is one of the main drivers of species extinctions. Therefore, measures are implemented to reduce the abundance of the invading species with the goal to mitigate its impact. These measures often lead to high labour and economic expenditures yet their effectiveness are often uncertain. To evaluate and thereby improve the mitigation of invasions, it is essential to understand the invasion process and the underlying mechanisms of the removal effort of the invading species. In this study, I use a trait and niche- based theoretical approach to study such processes and mechanisms. I simulate invasion into a residential community followed by simulated removal of the invading species. The invasion process reveals that the impact of the invading species is dependent on the niche width of the residential and the invading species, and on the niche position of the invading species. More specifically, a generalist invading a specialist community causes a decrease in species richness when invading at central niche positions. Furthermore, the simulation of the removal effort against the invader shows a stepwise mitigation effect along an increasing removal effort. This pattern is driven by the requirement of certain removal percentages to rescue residential species. My results thus provide a fundamental understanding of the invasion process itself, the effect that ecologically different invaders may have when invading different types of communities, and how different degrees of removal effort can mitigate negative effects on the invaded community. Such an understanding can act as a stepping-stone for future efforts that aim to increase the effectiveness of human measures against biological invasion. (Less)
- Popular Abstract
- The Equation of Invasion
Earth is facing the next mass species extinction and we humans are mainly responsible for it. One of the main drivers is biological invasion, which is understood as the establishment of a species into a habitat that is outside of its natural range. Biological invasions are often mediated by human trade and transport and are therefore part of the Era of Globalization, with the highest number of new species introduced ever observed. International committees such as the Convention on Biological Diversity have thus included the control of biological invasion into the so-called Aichi Targets. Even though a lot of money was spent to mitigate the effect of biological invasion during the last few decades, scientists... (More) - The Equation of Invasion
Earth is facing the next mass species extinction and we humans are mainly responsible for it. One of the main drivers is biological invasion, which is understood as the establishment of a species into a habitat that is outside of its natural range. Biological invasions are often mediated by human trade and transport and are therefore part of the Era of Globalization, with the highest number of new species introduced ever observed. International committees such as the Convention on Biological Diversity have thus included the control of biological invasion into the so-called Aichi Targets. Even though a lot of money was spent to mitigate the effect of biological invasion during the last few decades, scientists urge for either more funding or more efficient measures. The most efficient measure against biological invasion is of course the prevention of the establishment of the invasive species. But once the invader has established itself in the habitat, it is difficult to get rid of it. Nevertheless, environmental agencies spend time and money to remove individuals and are thereby hoping to mitigate the effect of the invader. To increase the efficiency of the applied measures, it is important to understand the processes of both the biological invasion and the removal effort.
A modeling approach is convenient to study such processes as it allows to disentangle associated factors. Such factors are for example, reproduction rate of the invading species, competition between invader and residents and whether the invader is a generalist or a specialist. Using theoretical modelling, I demonstrate that the biological invasion of a specialist into a generalist community is only possible when the specialist can utilize resources that are not available for the generalist community. However, such biological invasions do not negatively affect the biological community of resident species. Contrary, a generalist invading a specialist community leads to species extinctions when the generalist can utilize most of the available resources.
Furthermore, by simulating the removal of the invader, it was revealed that specific levels of removal percentages are required to prevent species extinctions. Between these removal percentages no further species are rescued from extinction. As the removal effort can be applied throughout the season, it can directly impact the reproduction of the invading species. In Figure 1 it can be seen how important the timing of the removal is, as it can almost halve the removal effort when applied in the start of the season.
These results strengthen and deepen the understanding of the biological invasion process and reveal the underlying mechanisms of the removal effort.
Master’s Degree Project in Conservation Biology, 45 credits 2023
Department of Biology, Lund University
Supervisor: Mikael Pontarp (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9114540
- author
- Ruile, Sebastian
- supervisor
- organization
- course
- BION02 20221
- year
- 2023
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- English
- id
- 9114540
- date added to LUP
- 2023-05-15 14:17:49
- date last changed
- 2023-05-15 14:17:49
@misc{9114540,
abstract = {{Biological invasion is one of the main drivers of species extinctions. Therefore, measures are implemented to reduce the abundance of the invading species with the goal to mitigate its impact. These measures often lead to high labour and economic expenditures yet their effectiveness are often uncertain. To evaluate and thereby improve the mitigation of invasions, it is essential to understand the invasion process and the underlying mechanisms of the removal effort of the invading species. In this study, I use a trait and niche- based theoretical approach to study such processes and mechanisms. I simulate invasion into a residential community followed by simulated removal of the invading species. The invasion process reveals that the impact of the invading species is dependent on the niche width of the residential and the invading species, and on the niche position of the invading species. More specifically, a generalist invading a specialist community causes a decrease in species richness when invading at central niche positions. Furthermore, the simulation of the removal effort against the invader shows a stepwise mitigation effect along an increasing removal effort. This pattern is driven by the requirement of certain removal percentages to rescue residential species. My results thus provide a fundamental understanding of the invasion process itself, the effect that ecologically different invaders may have when invading different types of communities, and how different degrees of removal effort can mitigate negative effects on the invaded community. Such an understanding can act as a stepping-stone for future efforts that aim to increase the effectiveness of human measures against biological invasion.}},
author = {{Ruile, Sebastian}},
language = {{eng}},
note = {{Student Paper}},
title = {{The Equation of Invasion Biological Invasion and the Human Measure Against it}},
year = {{2023}},
}