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Providing evidence to improve practice

Individual study: Assessment of effectiveness of protection strategies for large mammal herbivores in Tanzania

Published source details

Stoner C., Caro T., Mduma S., Mlingwa C., Sabuni G. & Borner M. (2007) Assessment of effectiveness of protection strategies in Tanzania based on a decade of survey data for large herbivores. Conservation Biology, 21, 635-646


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Legally protect habitat for mammals Terrestrial Mammal Conservation

A replicated, paired, site comparison study in 1990–2001 in seven savanna areas in Tanzania (Stoner et al. 2007) found that populations of more mammal species increased inside protected national parks than in adjacent unprotected areas, but that population declines were also more frequent in protected than unprotected areas. In all seven comparisons, populations of more mammal species increased in national parks (0–20%) than in unprotected areas (0–5%). However, in six of seven comparisons, populations of more mammal species also declined in national parks (5–62%) than in unprotected areas (0–21%). In one of seven comparisons, the opposite was found (national parks: 0%, unprotected areas: 22%). Between May 1990 and May 2001, large mammals in seven zones, each spanning a national park and surrounding area, were surveyed from aeroplanes. Planes followed transects and two observers recorded numbers of animals seen between parallel rods attached to the aircraft. Population densities were calculated and assigned to cells covering the area surveyed. Population estimates over 10 years in each cell were used to determine changes in both protected and unprotected areas.

(Summarised by Phil Martin)