Investors’ appetite for funds that aim to improve the environment and society, as well as making money, has grown quickly in 2019 — to the extent that some are beginning to push quite unconventional products. 

One such is the so-called Rhino Impact Bond, which is being coordinated by charity the Zoological Society of London and Conservation Capital, an environmental, social and governance funding consultant. It is billed as the first-ever financial instrument for species conservation and its surrounding habitat, and is due to launch next year.