COMMENTARY Trouble with the Gray Literature Richard T. Corlett 1 Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 ABSTRACT In much of the tropics, the gray literature—published by nongovernmental organizations, governments, intergovernmental organizations, consultancies, private com- panies, and individuals—has a greater volume than the peer-reviewed scientific literature in ecology and conservation. I discuss why this is a problem in terms of quality, discovery, access, and archiving. Unpublished dissertations and theses are another vast untapped source of information in tropical biology. Internet search engines can potentially integrate access to all information sources, but only if the producers of gray literature and theses greatly improve electronic access. Digital repositories can provide both this accessibility and permanent archiving. Key words: archives; data bases; digital repository; dissertations; gray literature; NGOs; peer review; theses. IF YOU ARE READING THIS, IT IS BECAUSE IT PASSED A FIRST SCREENING BY THE EDITOR OF BIOTROPICA, was sent out to referees, modified in the light of their comments, and a final version approved by all con- cerned. Unless everyone was asleep on the job, this process will have ensured that you are not totally wasting your time. Obvious errors and omissions will have been corrected and the conclusions will at least be defendable, if not necessarily correct. Moreover, you need not be reading this in 2011, but could be accessing it at any time in the future. In short, this article is now part of the scientific litera- ture: an accumulating body of formally published science. A min- imum quality standard is ensured by formal peer review, while accessibility follows from the desire of publishers to maximize their profits and authors to maximize their citations. Archiving in insti- tutional libraries is as permanent as anything is. Electronic journals and open access have modified this traditional model, but peer review is usually retained, publication is mostly by professionals, accessibility is increased, and the need for archiving is recognized (e.g., http://www.portico.org). In the tropics, however, there is an at least equal volume of material related to ecology and conservation in the so-called ‘gray literature’. There is no simple definition of which literature is ‘gray’, but the key feature is that it is not published and disseminated by commercial publishers, but by organizations where publishing is not the primary activity (http://www.greynet.org). Journals and monographs published by universities and other academic institu- tions are also usually considered ‘nongray’, but conference proceed- ings are definitely gray (e.g., Lacanilao 1997), unless published as part of a continuing series. In tropical biology, most gray literature is produced by nongovernmental organizations (NGOs, including charities, nonprofits, and various other civil society organizations), governments at various levels, intergovernmental organizations, such as the United Nations and World Bank, environmental con- sultancies, private companies involved in businesses other than publishing, and, increasingly, freelance individuals. This literature is not formally peer reviewed—often not reviewed at all—and the quality varies hugely. Most is initially made available on the Inter- net, if you know where to look, but much also is not, for a variety of reasons, including interagency rivalries, commercial sensitivity, government secrecy, fear of plagiarism, and lack of funding or technical skills. The gray literature appears to be most volumi- nous in Southeast Asia, which is underrepresented in the global scientific literature (Sodhi & Liow 2000), but it is a pantropical phenomenon. The most common complaints against the gray literature— low quality and low accessibility—might appear to cancel each other out, but quality and accessibility are not correlated. Most re- ports contain some useful information and the best are excellent. Most often it is the data that is of lasting scientific value, not the analysis and conclusions. The big international NGOs (BINGOs) have more money than most local researchers in the tropics, so their reports may have useful information derived from remote sensing, camera-traps, and other resource-intensive techniques, while gov- ernment departments have access to data that are not available to other researchers. Moreover, gray literature commissioned by governments may have large impacts on policy irrespective of its quality. In the tropics, the gray literature is often the only source of information on particular sites or projects, or on particular species (Mrosovsky & Godirey 2008). Distribution and status studies that ignore the gray literature may well be misleading. Meta-analyses that exclude the gray literature risk over-representing statistically significant results and large effect sizes for the simple reason that they are more likely to be published (Jennions & Mller 2002, Conn et al. 2003). Even the worst of the gray literature is at least a record of how governments and NGOs have spent other peoples’ money. The effectiveness of conservation efforts will only increase when it is possible to evaluate the results and see what worked and what did not (Ferraro & Pattanayak 2006, Linkie et al. 2008), yet this is rarely possible at present since past conservation efforts in the tropics—especially those that failed—are generally not accessibly documented. Even in the developed world, practical conservation Received 19 May 2010; revision accepted 15 July 2010. 1 Corresponding author; e-mail: corlett@nus.edu.sg BIOTROPICA 43(1): 3–5 2011 10.1111/j.1744-7429.2010.00714.x r 2010 The Author(s) 3 Journal compilation r 2010 by The Association for Tropical Biology and Conservation