1st, October, 2020 - University College, London - Research led by an international team in conjunction with the University College, London discussed how they've predicted there to be a 36% increase in invasive alien species by 2050 in comparison to 2005.There is significant correlation between the level of a nations GDP and the abundance of invasive species due to improvement in transport, infrastructure etc. It's expected that Europe will see the highest invasion in biological invasions with the predicted arrival of 2,500 species which will be a 64% increase. Invasive species have been an issue in Europe for the past 11 decades, however, enhancement in trapping methods have plateaued where kill traps and mark and recapture methods commonly being deployed (UCL, 2020). There is a large inventory of invasive species data available for island populations, however, this is not the case for mainland populations. Mainland populations are more complicated due to higher potentials of dispersal and information will be vital. This study has used a model with great variations between different regions where the largest increase predicted to be in Europe due to their connectivity to many other continent, high GDP, poor border control, strong political relationships with other high GDP nations etc. Australia have been estimated to seeing the lowest increase due to strong border controls and their dis connectivity from other nations (Blackburn et al, 2019).
The best time to put controls into place is during the early stages before these populations expand and disperse. Constant surveillance using meta genomics would be a useful tool where it will help detect early introduction where the intensity of invasion is low and will help understand pathway patterns. The success of establishment is heavily related to the propagule pressure which refers to the increased risk of successful establishment is heavily related to the number of individuals introduced into a foreign environment (Amador-Vargas et al, 2018: Blackburn et al, 2019).
The most destructive assemblage are known as Invasive Alien Predators where they exploit the behavioral/ evolutionary naeivity from the native prey species. A cyclical relationship is typically formed between the predator-prey species which ensures the survival of both species. This relationship is formed through many thousand years of co-existence where they evolve in relation to each other (Red Queen Hypothesis), however, when a predator and prey species not native to one another are exposed to one another, there isn't sufficient time to evolve to develop an adequate form of defense (:Simberloff et al, 2000). Other invasive species include establishment of floral species such as rhododendron (rhododendron ponticum) reduces floral diversity where they use their thick leaves to block light and excrete toxic chemicals to prevent the establishment of juveniles. This will then create a bottom up impact where species further up the food chain are impacted by the domino effect created by the reduced species diversity of floral species (Simberloff et al, 2000: Thébault et al, 2017: Amador-Vargas et al, 2018).
References
· Amador-Vargas, S. Blackburn, T. Braga, R.
Cassey, P. Debille, S. Enders, M. Erhard, F. Farji-Brener, A. Fox, G.
García-Díaz, P. Gómez Aparicio, L. Griesemer, J. Heger, T. Jeschke, J.
Lockwood, J. Lortie, C. Müller, C. Nordheimer, R. Pyšek, P. Scheiner, S. Starzer,
J. Torchyk, O. Vitule, J. (2018) ‘INVASION BIOLOGY Hypothesis and Evidence’,
Jeschke, J. Heger, T. Edition 9, pp. 3-124, CABI, Oxfordshire.
Blackburn, T.M. Bellard, C. Ricciardi, A. (2019) 'Alien versus native species as drivers of recent extinctions'. Frontiers in Ecology and the Environment, DOI: 10.1002/fee.2020
· Vilà, M. Espinar, J.L. Hejda, M. Hulme, P.E. Jarošík, V. Maron, J.L. Pergl, J. Schaffner, U. Sun, Y. Pyšek, P. (2011) ‘Ecological
impacts of invasive alien plants: a meta‐analysis of their effects on species,
communities and ecosystems’, Ecology Letters, 14(7), pp. 702-706, doi: https://doi.org/10.1111/j.1461-0248.2011.01628.x
