[Extract] Governments, businesses, financial institutions and local communities are increasingly using biodiversity offsets, also known as compensatory mitigation, as a putative mechanism to achieve 'no net loss' (NNL) of biodiversity as a result of specific development projects (McKenney & Kiesecker, 2010; Quetier & Lavorel, 2011; Gardner et al., 2013). The Business and Biodiversity Offsets Programme (BBOP), an international collaboration for the development of offset methodologies, defines biodiversity offsets as 'the measurable conservation outcomes resulting from actions designed to compensate for significant residual adverse biodiversity impacts arising from project development after appropriate prevention and mitigation measures have been taken. The goal of biodiversity offsets is to achieve no net loss and preferably a net gain of biodiversity on the ground with respect to species composition, habitat structure, ecosystem function and people's use and cultural values associated with biodiversity' (BBOP, 2009). Proposals are already proceeding in the European Union (EU) for a NNL initiative as part of the 'EU Biodiversity Strategy to 2020' – with possible operational principles that include offsetting schemes (see http://ec.europa.eu/environment/nature/biodiversity/nnl/index_en.htm). Madsen et al. (2011) identified legislation mandating compensatory biodiversity conservation mechanisms (including offsets) in 45 countries, with a further 27 under development and this number is likely to have grown since.