Crime-Fighting Statistical Tool Used to Track Down Invasive Species
Criminology Meets BiodiversityGeographic profiling, as described by Wikipedia, is a "criminal investigative methodology that analyzes the locations of a connected series of crimes to determine the most probable area of offender residence. By incorporating both qualitative and quantitative methods, it assists in understanding spatial behaviour of an offender and focusing the investigation to a smaller area of the community." It's typically used in cases of serial murder or rape (but also arson, bombing, robbery, and other crimes)... But it might not be used to track down invasive species of animals and plants that can potentially severely damage biodiversity. Quite a change, but as with many discoveries, tools from one field are put to new uses in another.
Because invasive species are considered to be the second biggest threat to biodiversity after habitat destruction, and because the environmental and economic impact of this is felt on a gigantic scale, it is quite important to devise effective strategies to track and control their spread.
A team of scientists from the Queen Mary’s School of Biological and Chemical Sciences has shown that geographic profiling - the criminology statistical tool - can be applied to invasive species:
Writing in the journal Ecography, the team describe how they used computer simulations to compare GP to existing ways of monitoring invasive species. The team also analysed historical data from the Biological Records Centre (BRC) for 53 invasive species in Great Britain, ranging from marine invertebrates (such as the Japanese oyster) to woody trees (for example, Norway spruce), and from a wide variety of habitats (including coastal habitats, woodland and man-made habitats) to attempt to identify the source of each species. In both the computer simulations and the real datasets, GP dramatically outperformed other techniques, particularly as the number of sources (or potential sources) increased. Dr Steven Le Comber who led the study, explains:
“We found that existing methods performed reasonably well finding a single source, but did much less well when there were multiple sources – as is typically the case as invasive species spread The results show that geographic profiling could potentially be used to control the spread of invasive species by identifying sources in the early stages of invasions, when control efforts are most likely to be effective.”
Because resources to fight invasive species are always very limited, such a tool can be extremely helpful in directing those resources to where they will have the biggest impact, or the most bang for the buck.