Prioritising research efforts for effective species conservation: a review of 145 years of koala research

In many countries, more resources are required for the conservation of threatened species than are made available. Australia, the home to many unique mammalian species, has been identified as one of the top seven countries worldwide with the highest biodiversity loss and lowest amount of funding dedicated to conservation. Conservation action is generally determined by what we perceive to be the most significant conservation problems; therefore, identifying potential biases in research effort is crucial for prioritising research actions for effective conservation outcomes. We reviewed the published literature on the koala Phascolarctos cinereus, a vulnerable arboreal marsupial. Our aim was to assess and quantify research efforts (number of publications) and research coverage (diversity of subject areas) of koala-related research. We then focused on the research effort of threats to identify primary threats and fields requiring further research. Using a combination of key words, journal name, study title, and methods, we reviewed and categorised 714 publications to identify the focus of research efforts. We investigated subject area, geographic and temporal publication patterns, and the extent to which primary threats have been addressed. We found a trend of increasing number of publications with a diversification of threat-based studies, and identified both geographic and subject bias in research effort. Geographic bias in the volume of research indicates that the level of koala research between regions may be a response to the species’ distribution, status and impact of threats. Research areas ‘anatomy and physiology’ and ‘threats’ received comparatively more research attention than other areas. We found a research bias between threats, with ‘disease’ representing a high percentage of all threat-based publications. Areas that have been identified but are receiving little research attention include habitat selection and use, along with the effects of habitat loss, fragmentation, and degradation.