A few years ago, a relatively new idea emerged onto the scene of ecology known as assisted migration. Simply defined as the deliberate moving of species from their present habitat to a new area in hopes of preserving that species.
Although the concept of assisted migration has only recently become a topic of scientific debate, the truth is it has been in practice for quite some time both unintentionally as well as consciously. Whether through gardening, reforestation, or the like, humans have been moving species around for years. Likewise, animals have also long been aiding this process. Blue jays, for example, disperse Beech seeds by dropping the seeds around as they fly. In a similar vein, assisted migration has been carried out willingly. Take the Assisted Migration Adaptation Trial (AMAT), citizen naturalists such as the Torreya Guardians and the systematic movement of trees in British Colombia. These initiatives have already begun to set the wheels of assisted migration in motion.
Naturally, while there are those who support such activity, a many handful remain ambivalent to accepting it. As Marris points out in her tale of Florida Torreya, populations of trees are being moved but entire tree species are not yet being planted outside of their historical range. This is supported by the belief that the assisted migration of seeds is not nearly as risky as the assisted migration of species. But why would something be so risky if it has long been in practice? There are still too many unknowns, and this is what has sparked public controversy. No evidence has been collected to prove that every species moved will survive in its new environment; perhaps we would be doing more harm than good. For those that do survive and flourish, the movement of an entire species might endanger other ecosystems by potentially introducing an invasive species that may drive out natives. But then again, as Marris alludes, would these “invasive” species really be as bad as we make them out to be?
It seems that the bottom line regarding assisted migration is analogous to flipping a coin—we do not know the outcome. Of course, moving species “willy-nilly” is not the most desirable technique, but what if there was a more scientific approach that could determine what species to move and where to move them? In the article written by Puth and Burns, studying species richness is described as an advantageous method that allows ecologist to study the patterns of species increase or decline in a community. One of the biggest obstacles, however, is the lack of sufficient ecological data amongst urban communities. If this shortcoming could be remedied, I think species richness could serve as an excellent indicator of what species need to be brought to urban ecosystems.
While a lack of concrete evidence supporting assisted migration is a valid base for skepticism, the coupling of species richness and assisted migration may not be a bad idea. Some believe assisted migration is nothing more than the latest chic trend, others believe it contradicts the basis of preservation by violating the baseline. I think it’s worth a shot.
