This is the fifth in our annual series of horizon scans published in TREE.
•
We identify 15 issues that we considered insufficiently known by the conservation community.
•
These cover a wide range of issues. Four relate to climate change, two to invasives and two to disease spread.
•
This exercise has been influential in the past.
This paper presents the output of our fifth annual horizon-scanning exercise, which aims to identify topics that increasingly may affect conservation of biological diversity, but have yet to be widely considered. A team of professional horizon scanners, researchers, practitioners, and a journalist identified 15 topics which were identified via an iterative, Delphi-like process. The 15 topics include a carbon market induced financial crash, rapid geographic expansion of macroalgal cultivation, genetic control of invasive species, probiotic therapy for amphibians, and an emerging snake fungal disease.