Biodiversity - big word, big meaning. It exists in many facets - in nature and biology above all as the diversity of genes, species and ecosystems. All three are interwoven in a fine web and are of enormous importance for the world to function as it does. For all their presumed independence, humans are not immune from having to fit into this network. For as the English writer John Donne knew: "No man is an island, entire of itself; every man is a piece of the continent, a part of the main."7
Whether Canada or Peru - our protected areas are characterized by their enormous biodiversity. These cranes regularly visit our protected areas on Porcher Island, Western Canada.
Above all, human influence continues to ensure that more and more of the naturally valuable areas are becoming smaller, that species can no longer survive and that entire ecosystems are losing their functional diversity.
Species extinction is particularly advanced: around a third of all species are endangered1 and every few minutes another species becomes extinct - and the trend is rising2. In addition, the frequency of living creatures is also decreasing. If we look at vertebrates alone, their numbers have more than halved compared to 19703. The main cause of this catastrophic species extinction is the loss of important habitats.
The decline in biodiversity has fatal consequences, as species-rich ecosystems are more stable, better able to compensate for deficits and also ensure food security and quality of life for humans2. If one species disappears, this can lead to a kind of domino effect in which the habitat of other species is also threatened - for example, if the extinct or displaced species has created biotopes with its way of life that enable other bioorganisms to survive in the first place1.
No man is an island, entire of itself; every man is a piece of the continent, a part of the main.
John Donne
Writer
This makes it all the more important to preserve areas that are of key importance for the world's biodiversity. These include areas that are particularly species-rich and unique in their ecosystems - such as our protected areas in Canada (Porcher Island) and Peru (Madre de Dios).
The Canadian forest is even one of the so-called Key Biodiversity Areas, i.e. areas that are particularly worthy of protection and are characterized by their high biodiversity. But how do you actually measure biodiversity? After all, a census of wild animals is too abstruse, isn't it?
It should be clear to everyone that wolves, grizzlies and eagles do not put their crosses on a piece of paper. And yet a modern form of monitoring is not so far removed from this idea. With eDNA (short for Environmental DNA), the presence of one or more species in a defined area can be recorded in a minimally invasive way. By excreting faeces, urine or body cells, living organisms also leave their DNA in bodies of water and on surfaces4. This not only makes it easier to record rare and shy species, but also provides a more complex picture of thehabitat5,6.
The DJI Matrice drone with the ETH Zurich robot on its way into the treetops to take eDNA samples.
Minimally invasive interventions through sampling (hardly any disturbance to wildlife)
Cost efficiency through an effective approach
Detectable organisms that cannot be seen with the naked eye
easy comparability over time (later samples show how species diversity has or could have changed)
Extensive provisions possible
The only disadvantage of the method is that the comparability and informative value can initially only refer to the specific area in view of the data situation that is still being developed. In the future, however, the data should be far more comprehensive, which will also improve comparability many times over.
Text: Sarah Sassenhagen
1https://www.deutschlandfunk.de/biodiversitaet-artenvielfalt-artensterben-umweltschutz-100.html
2https://www.uni-muenster.de/news/view.php?cmdid=10285
3https://www.mpg.de/biodiversitaet
4Schmidt, Benedikt R.; Ursenbacher, Sylvain: Umwelt-DNA als neue Methode zum Artnachweis in Gewässern. Zeitschrift für Feldherpetologie, 2015 (22), 1 - 10.
(https://www.researchgate.net/publication/273146140_Umwelt-DNA_als_neue_Methode_zum_Artnachweis_in_Gewassern)
5Bohmann, Kristine et al.: Environmental DNA for wildlife biology and biodiversity monitoring. Trend in Ecology & Evolution, 2014 (29, 6), 358 - 367.
6Sahu, Ashish et al.: Environmental DNA (eDNA): Powerful technique for biodiversity conservation. Journal for Nature Conservation, 2023 (71), 126325.
(https://www.sciencedirect.com/science/article/abs/pii/S1617138122001984?via%3Dihub)
7https://www.goodreads.com/quotes/5437-no-man-is-an-island-entire-of-itself-every-man
