Author’s note: this post is part of the “Science of Tatooine” blog carnival. Though obviously about science fiction and not the real world, it includes real ecological theories, and it uses some real peer-reviewed scientific papers as references. Whenever possible, I’ve linked to accessible copies of those papers and explainers of these ecological terms. Many of the same issues are associated with shark population declines.
Predators play an important role in structuring ecosystems, with predator population declines being linked to a variety of negative ecological effects. Here, we present evidence that the planet Tatooine, famous throughout the Galaxy for being a desert planet, experienced desertification as a result of unintended changes in herbivore populations caused by the intentional large-scale killing of apex predators by offworld colonists. Fossil evidence and interviews showing traditional ecological knowledge suggest that once-abundant Krayt dragons were hunted to near extinction by early human colonists. As a result of the decline in predation, populations of large herbivorous banthas populations grew out of control and overgrazed the plants once found throughout Tatooine.
Though the planet Tatooine in the Tatoo system of the Outer Rim is known by researchers to have once been covered by oceans and lush vegetation, it is commonly known now as a desert planet (source). While it is famous in Republic circles primarily for being the home of Jedi Master Skywalker, Tatooine also has native sentient species, including Jawas and Tusken Raiders (the latter are derisively referred to by locals as “sand people” ). Native non-sentient animals include banthas (large herbivores used as beasts of burden) and the now mostly extinct Krayt dragon (a large predatory species that fed on banthas).
I particularly like that they go into enough detail to lay out options for incorporating predation into fisheries. Personally, I’m a big fan of the “second fleet” option, in which predators are counted as another source of fishing mortality (and some of my favorite papers are cited in support of it). It does require the most effort, but provides the most accurate estimations of predation mortality (and justifies funding for diet studies? Please?). Multi-species models are ideal, and really the only way to conclusively prove that trophic cascades are actually happening. Precautionary buffers, in my opinion, should really follow thorough diet studies, but are certainly another important aspect of ecosystem-based management.
It’s neat to finally see this subject getting some attention. Here’s hoping the word continues to get out about the importance of shark puke.