First-Ever Landscape-Wide Study of Elephants and Great Apes

(sorry I'm a bit late on posting this, but better late than never :) - MA)
from SCIENCE DAILY
The Wildlife Conservation Society announced the results of the first-ever evaluation of a large, "landscape-wide" conservation approach to protect globally important populations of elephants and great apes.

The study looked at wildlife populations in northern Republic of Congo over a mosaic of land-use types, including a national park, a community-managed reserve, and various logging concessions. It found that core protected areas -- coupled with strong anti-poaching efforts -- are critical for maintaining populations of forest elephants, western lowland gorillas, and chimpanzees.

The region, known as the Ndoki-Likouala Conservation Landscape, is considered one of the most important sites in Central Africa for all three species. The Wildlife Conservation Society has been working in the landscape since 1991 and helped establish Nouabalé-Ndoki National Park in 1993.

The study appears in the April 23rd edition of the journal PLoS ONE. Authors include Wildlife Conservation Society researchers Emma Stokes, Samantha Strindberg, Parfait Bakabana, Paul Elkan, Fortuné Iyenguet, Bola Madzoke, Guy Aíme Malanda, Franck Ouakabadio and Hugo Rainey; Brice Mowawa of the Ministre de l'Economie Forestière, Republic of Congo; and Calixte Makoumbou, formerly with WCS Congo Program.

The authors found that protected areas remain a key component of the landscape for all three species. Chimpanzees and elephants are particularly sensitive to human disturbance outside the Nouabalé-Ndoki National Park, and the park plays a major role in their distribution. In fact Nouabalé-Ndoki National Park may be one of the most important sites for chimpanzees in the Congo Basin with some of the highest densities recorded in Central Africa.

The study also found that logging concessions that have wildlife management in place, including protection of key habitats and anti-poaching patrols, can support important populations of elephants and gorillas. However, the authors warn that logging concessions are only of conservation value if there are strict anti-poaching measures in place, and if they are close to protected areas free of human disturbance. As evidence, the study showed the results of surveys in a logging concession without any anti-poaching measures or wildlife management where abundance of all three species was very low.

"Protected areas free of human disturbance, logging, or roads remain key to the protection of great apes and elephants," said WCS researcher Emma Stokes, the study's lead author. "Landscape conservation should focus on protected areas surrounded by other land-use types that also have wildlife management in place."

The forests of the Congo Basin are one of the last remaining tropical wildernesses and a top priority for biodiversity conservation.

Commercial logging is prevalent throughout much of the Congo Basin, with over 30 percent of native forest allocated to logging concessions compared to only 12 percent under protection. More than 50 percent of the current range of western gorillas and chimpanzees is estimated to lie in active logging concessions.

"This study shows that landscape-wide conservation can work in Central Africa -- provided there are the resources and political will to save wildlife over large areas," said James Deutsch, Director of the Wildlife Conservation Society's Africa programs. "Conservation on this scale is difficult and expensive, but absolutely necessary if we hope to save viable populations of elephants and great apes. At the same time, the government's capacity to follow up and take legal action against poachers should be strengthened and is a key to maintaining the protection of the forests and their wildlife."

The authors estimated elephant and great ape density using distance sampling surveys of elephant dung piles and great ape nests.

The surveys presented in this paper were made possible through generous funding from the U.S. Agency for International Development Central Africa Regional Program for the Environment (CARPE) and U.S. Fish and Wildlife Service Great Ape Conservation Fund.

Currently, WCS advocates the speedy passage of HR 4416, the Great Ape Conservation Reauthorization Act, which would continue government support for the Great Ape Conservation Fund, and applauds Rep. George Miller (D-CA) for leading the effort. In January, Dr. Deutsch testified before a Congressional panel on behalf of WCS in support of the legislation.

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Reference
Stokes EJ, Strindberg S, Bakabana PC, Elkan PW, Iyenguet FC, et al. (2010) Monitoring Great Ape and Elephant Abundance at Large Spatial Scales: Measuring Effectiveness of a Conservation Landscape. PLoS ONE 5(4): e10294. doi:10.1371/journal.pone.0010294

Abstract
Protected areas are fundamental to biodiversity conservation, but there is growing recognition of the need to extend beyond protected areas to meet the ecological requirements of species at larger scales. Landscape-scale conservation requires an evaluation of management impact on biodiversity under different land-use strategies; this is challenging and there exist few empirical studies. In a conservation landscape in northern Republic of Congo we demonstrate the application of a large-scale monitoring program designed to evaluate the impact of conservation interventions on three globally threatened species: western gorillas, chimpanzees and forest elephants, under three land-use types: integral protection, commercial logging, and community-based natural resource management. We applied distance-sampling methods to examine species abundance across different land-use types under varying degrees of management and human disturbance. We found no clear trends in abundance between land-use types. However, units with interventions designed to reduce poaching and protect habitats - irrespective of land-use type - harboured all three species at consistently higher abundance than a neighbouring logging concession undergoing no wildlife management. We applied Generalized-Additive Models to evaluate a priori predictions of species response to different landscape processes. Our results indicate that, given adequate protection from poaching, elephants and gorillas can profit from herbaceous vegetation in recently logged forests and maintain access to ecologically important resources located outside of protected areas. However, proximity to the single integrally protected area in the landscape maintained an overriding positive influence on elephant abundance, and logging roads – even subject to anti-poaching controls - were exploited by elephant poachers and had a major negative influence on elephant distribution. Chimpanzees show a clear preference for unlogged or more mature forests and human disturbance had a negative influence on chimpanzee abundance, in spite of anti-poaching interventions. We caution against the pitfalls of missing and confounded co-variables in model-based estimation approaches and highlight the importance of spatial scale in the response of different species to landscape processes. We stress the importance of a stratified design-based approach to monitoring species status in response to conservation interventions and advocate a holistic framework for landscape-scale monitoring that includes smaller-scale targeted research and punctual assessment of threats.