How to hunt a species to extinction

Overexploitation is regarded as one of the main threats to biodiversity, with a number of species extinctions directly linked to our ability to efficiently hunt and capture (or in the case of plants remove) a whole range of different taxa. But wait a minute - surely if a species becomes too rare, it will eventually become uneconomical to hunt - even if they are worth a lot of exploitation will stop?  Not so say the authors of a new paper published in TREE last month.  In a scenario which they have coined 'opportunistic extinction', species that are no longer targeted for exploitation can still be caught if we stumble across them in our search for something more common.  In this situation, the rare species is whisked up, providing a tidy profit.

The authors Trevor A Branch, Steven Purcell and Aaron Lobo have provided a great overview of their paper and crucially its implications.

If you have access to the journal Trends in Ecology and Evolution, you can have a look at the paper

Image: The sperm whale was heavily hunted from the 18th to 20th century, primarily for its  spermaceti which had many applications including soap, candles, lamp oil, and pencils.  Credit: Peter G. Allinson, M.D. 2009/Marine Photobank