Image Credit: California Department of Fish and Wildlife, CC BY 2.0, Image Cropped
Angling as a source of non-native freshwater fish: a European review (2019) Carpio, De Miguel, Oteros, Hillstrom & Tortosa, Biological Invasions, doi.org/10.1007/s10530-019-02042-5
People love fishing. It’s an intrinsic part of some people’s lives, whether as a livelihood or a past-time. People who have grown up fishing often have specific species that they enjoy fishing for. Nothing wrong with that.
Yet people’s desire to go after one fish species will often lead them to move that species around. This can happen on a small scale, with people moving a species from one lake to another slightly closer to their homes. Or it can happen on a massive one, with a species being transported to new continents.
This has shaped entire freshwater communities in modern-day Europe, where 195 species now reside that have no natural range in the continent. Most of these have been introduced since the nineteenth century, which is around the time that fishing became a popular recreational activity. This week’s authors wanted to find out what the role of recreational fishing was in shaping the make-up of today’s invasive freshwater fish populations in Europe.
Image Credit: pxhere, CC0 1.0, Image Cropped
When I’ve talked about anthropogenic effects, I’ve been guilty of focussing far too much on climate change and land use. But our dependence on toxicants like pesticides also has a profound impact on ecosystems, freshwater ecosystems in particular. On her recent visit to NTN in Trondheim, I spoke to ecotoxicologist Dr. Marie-Agnes Coutellec about her research group’s work with pesticides, and the likely future for much of Europe’s aquatic life.
Forests such as Białowieska in Poland perform a wide range of functions, but if its biodiversity rises, how will this change? (Image Credit: Jacek Karczmarz, CC BY 3.0)
Biotic homogenization can decrease landscape/scale forest multifunctionality (2016) von der Plas et al., Proceedings of the National Academy of Sciences of the United States of America, 113
Any ecosystem performs a multitude of functions, benefiting both the species that live in it and the humans who interact with it, from litter decomposition to resistance of drought to timber production. As such, maintaining high levels of ecosystems is a well-studied concept, and it has been posited that high levels of biodiversity increase the levels functions an ecosystem can perform, or its multifunctionality.
But while the word biodiversity is recklessly bandied about these days, scientifically it’s a somewhat vague term. At an ecosystem level, you may have patches of very high local (or alpha) diversity, but the turnover of species between patches (beta diversity) might be quite low. The variation in types of biodiversity may influence your ecosystem multifunctionality. For instance, patches of high alpha diversity might lead to high levels of functionality in some patches, but little functionality elsewhere, whereas high levels of beta diversity may lead to low levels of functionality, but many functions. This paper investigates relationships between different biodiversity levels and ecosystem multifunctionality.