Caro, T

Dollar, L

Durant, SM

Jacobson, AP

Kiffner, C

Pimm, SL

Riggio, J

van Aarde, RJ

UCL Discovery

Lion populations may be declining in Africa but not as Bauer et al. suggest  Jason Riggio1, Tim Caro1, Luke Dollar2,3, Sarah M. Durant4, Andrew Jacobson4,5, Christian Kiffner6, Stuart L. Pimm3, Rudi J. van Aarde7  1Department of Wildlife, Fish and Conservation Biology, University of California, Davis, CA 95616 USA  2Department of Biology, Pfeiffer University, Misenheimer, NC 28109, USA 3Nicholas School of the Environment, Duke University, Durham, NC 27708, USA 4Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK  5Geography Department, University College London, Gower Street, London, UK  6Center for Wildlife Management Studies, The School for Field Studies, PO Box 304 Karatu, Tanzania 7 Conservation Ecology Research Unit, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa   Historical knowledge and recent surveys attest that lions are declining across parts of Africa (1, 2). We applaud Bauer et al. assembling available counts because they motivate better monitoring and conservation support. Their own data, however, reject their claims that lions are “declining everywhere, except in four southern countries ” and that lions increase only where “intensively managed.”  First, there are some stable and increasing populations in all regions. Moreover, not weighting for population size strongly biases regional population projections. By treating all populations — small and large — equally, the authors mislead on the overall trend of lion populations. In Southern Africa, of 21 populations only one (Okavango) shows a decline, but the increasing populations are mostly in small, fenced reserves that, combined, support few lions. Niassa is a large, increasing population but considered a “special case.” Of nine West and Central Africa lion populations, the largest are stable (Bénoué, 200) or increasing (Pendjari, ~100). The declining populations are the smallest, with starting populations of fewer than 70 lions. In East Africa, of 15 populations, 4 are increasing, and 4 are stable. Only 4 show declines strong enough to halve in 20 years (λ < 0.965). Maasai Mara and Katavi are the only large populations showing such strong declines. Second, Bauer et al. misrepresent the data from these two sites:  Maasai Mara: Supplementary Dataset S1 records 483 lions in 1991 and 286 individuals in 2005. The corresponding dates and densities (3) — 31.56 lions/100 km2 and 18.69 lions/100 km2— do not match those in their assumed respective citations (4, 5) — 29.4 lions/100 km2 in 1992 and 36.9 lions/100 km2 in 2003 (Ref (6) does not mention lions). References (4, 5) actually show lions increasing from 450 to 560 individuals between 1992 and 2003. Katavi: The Katavi data are from road transect surveys designed for herbivores (7). Extrapolating from these transects of limited length and frequency — and hence few lion observations — to the whole park distorts. This is evidenced by a 2005 playback survey that estimated 168 (77-468) lions in the park (8), and continuing recent documentation of lion prides (9). Bauer et al. neglect these data and report 0 from 2002 onwards. Finally, claims of the efficacy of fencing for lion conservation are misplaced (10). For example, contrary to statements (Fig. S2), Kgalagadi and is not completely fenced while the eastern side of Kruger National Park has not been fenced since 2002. Moreover, small fenced reserves make questionable contributions to lion conservation (10).  Certainly, serious threats are mounting and demand attention. That said, it is premature, indeed insensitive, to level blanket criticism at countries outside Southern Africa. The data show that authorities have maintained effective protection for many lion populations and should be congratulated where they have succeeded. Conservationists should also be wary of overstating widespread declines. If such claims are later rejected, science loses credibility. Conservation needs transparency in methods and data, and honest appraisal of the evidence and considerable uncertainties. Bauer et al. have not provided these.  1. Henschel et al. 2014 2. Riggio et al. 2013 3. Packer et al. 2013 4. Ogutu & Dublin 1998 5. Ogutu et al. 2005 6. Ogutu et al. 2011 7. Caro 2011 8. Kiffner et al. 2009 9. http://www.nomad-tanzania.com/blogs/chada-katavi 10. Creel et al. 2013   

Lion populations may be declining in Africa but not as Bauer et al. suggest

http://discovery.ucl.ac.uk/1473612/1/jacobson%20PNAS%201030%202.0%20consensus.pdf

Lion populations may be declining in Africa but not as Bauer et al. suggest

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