William D. Newmark

Conservation attitudes of local people living adjacent to five protected areas in Tanzania

Abstract A questionnaire survey of conservation attitudes of 1190 people living adjacent to Arusha, Tarangire, Lake Manyara, and Mikumi National Parks and the Selous Game Reserve showed that over 71% were opposed to the suggested abolishment of the adjacent protected area. However, when local people were asked, ‘What good things do people from the adjacent park do?’, 47% reported ‘nothing’. If these same individuals are combined with those who did not answer this question over 71% also held negative or neutral attitudes towards protected area employees. Over 74% of local people felt that poachers are law-breakers. Using a three-way log linear analysis we examined how resource use patterns and problems, and past interactions with the protected area and protected area employees, influence conservation attitudes. Past problems with wildlife, a lack of perceived effectiveness in its control, a shortage of grazing and farming land, problems with flooding, and long-term residency were significantly correlated with support or neutral attitudes toward the abolishment of the adjoining park or reserve. The absence of perceived visitation to a village by a protected area employee, the lack of effectiveness in controlling wildlife, small farm size, problems with flooding, and long-term residency were related to negative attitudes towards protected area employees. Finally, the frequency with which an individual ate meat per month was related to opinions about whether poachers are law-breakers.

Conserving Wildlife in Africa: Integrated Conservation and Development Projects and Beyond

onservationists in Africa are struggling to develop new approaches to protect the continent’s spectacular natural heritage. The challenge is to design strategies that not only will ensure the long-term viability of species and ecosystems but also will be politically and economically acceptable to local communities and governments. One approach that has gained considerable attention in recent years is the integrated conservation and development project (ICDP), which attempts to link the conservation of biological diversity within a protected area to social and economic development outside that protected area. In ICDPs, incentives are typically provided to local communities in the form of shared decision-making authority, employment, revenue sharing, limited harvesting of plant and animal species, or provision of community facilities, such as dispensaries, schools, bore holes, roads, and woodlots, in exchange for the community’s support for conservation. The ICDP approach to conservation in Africa began in earnest in the 1980s and 1990s, although efforts to link wildlife conservation with local development go back to the 1950s in a few protected areas in Africa, such as Ngorongoro Conservation Area in Tanzania. Currently, much of the funding by major bilateral and multilateral donors to protected areas in Africa is in the form of ICDPs. A recent review (Alpert 1996) suggests that there have been more than 50 such projects in 20 countries. Given the popularity of ICDPs, it is discouraging that so

Isolation of African protected areas

The increasing isolation of protected areas poses a serious threat to the long-term viability of many wildlife populations and migrations in Africa. While ecologists have debated the impact of isolation on wildlife populations in reserves, field studies conducted over the past decade now provide a much clearer understanding of the effects. The primary drivers of isolation of protected areas are habitat loss, fences and roads, overhunting, and disease. These drivers restrict the movement of wildlife into and out of reserves and create sinks in the increasingly human-dominated matrix that surrounds most reserves. Post-establishment patterns of extinction of large mammal species in African reserves indicate that area and edge effects are important determinants of species persistence. Interactions and feedbacks between reserve isolation, human-related activities, and natural processes within and outside reserves can occur, yet are poorly understood. The problem of reserve isolation must therefore be addressed with a multi-pronged conservation strategy.

FOREST AREA, FRAGMENTATION, AND LOSS IN THE EASTERN ARC MOUNTAINS: IMPLICATIONS FOR THE CONSERVATION OF BIOLOGICAL DIVERSITY

ABSTRACT An understanding of forest area, fragmentation and loss is central to developing strategies to conserve biological diversity in the Eastern Arc Mountains. Using recent 1:250,000 land cover and use maps (Tanzanian Ministry of Natural Resources and Tourism, 1996) and 1:250,000 and 1:500,000 topographic maps, I examine natural forest area, fragmentation, and loss in the Eastern Arc Mountains. I estimate the maximum total area of natural forest, open as well as closed forest, in the Eastern Arc Mountains is 5,340 km2. The remaining natural forest in the Eastern Arc Mountains is highly fragmented. The median patch size is 10.2 km2, and the mean patch size is 58.0 km2. Based upon the estimates of various workers, approximately 1,447 km2 of closed forest remains in the Eastern Arc Mountains or 27 % of the remaining natural forest. Comparisons of the current to prehistoric forest cover suggest that 77 % of the original forest has been lost over the last approximately 2,000 years.

Legal and biotic boundaries of western North American national parks: A problem of congruence

Abstract The boundaries of a national park may be defined in terms of its legal and biotic boundaries. The legal boundaries are the boundaries established by the highest legislative authority of a country. The biotic boundaries are hypothetical boundaries which would be necessary to maintain existing ecological processes and a given assemblage of species within a national park. Practically, the biotic boundaries are defined as those hypothetical boundaries encompassing the entire watershed of a park and an area of sufficient size to maintain a minimum viable population (MVP) for the terrestrial non-volant species with the largest home range found within the current legal boundaries. The legal and biotic boundaries for eight of the largest continental national parks and park assemblages in western North America were examined for congruence. The legal boundaries for seven of the eight parks/park assemblages were found to be larger than the biotic boundaries by a factor of 1·2–9·6 for a MVP=50 and 6·0–96·0 for a MVP=500. One to seven percent of all the mammals, excluding chiropterans, found currently in seven of the eight national parks/park assemblages have an area requirement (MVP=50 × home range) exceeding the legal boundaries. It is urgent while an opportunity exists that an active effort be made to enhance the congruence of the legal and biotic boundaries of these parks and park assemblages through the cooperative management of adjacent public and private lands so as to minimize the potential loss of wildlife.

Habitat fragmentation reduces nest survival in an Afrotropical bird community in a biodiversity hotspot

Ecologists have long hypothesized that fragmentation of tropical landscapes reduces avian nest success. However, this hypothesis has not been rigorously assessed because of the difficulty of finding large numbers of well-hidden nests in tropical forests. Here we report that in the East Usambara Mountains in Tanzania, which are part of the Eastern Arc Mountains, a global biodiversity hotspot, that daily nest survival rate and nest success for seven of eight common understory bird species that we examined over a single breeding season were significantly lower in fragmented than in continuous forest, with the odds of nest failure for these seven species ranging from 1.9 to 196.8 times higher in fragmented than continuous forest. Cup-shaped nests were particularly vulnerable in fragments. We then examined over six breeding seasons and 14 study sites in a multivariable survival analysis the influence of landscape structure and nest location on daily nest survival for 13 common species representing 1,272 nests and four nest types (plate, cup, dome, and pouch). Across species and nest types, area, distance of nest to edge, and nest height had a dominant influence on daily nest survival, with area being positively related to nest survival and distance of nest to edge and nest height being both positively and negatively associated with daily nest survival. Our results indicate that multiple environmental factors contribute to reduce nest survival within a tropical understory bird community in a fragmented landscape and that maintaining large continuous forest is important for enhancing nest survival for Afrotropical understory birds.

Dynamics of extinction debt across five taxonomic groups

Species extinction following habitat loss is well documented. However, these extinctions do not happen immediately. The biodiversity surplus (extinction debt) declines with some delay through the process of relaxation. Estimating the time constants of relaxation, mainly the expected time to first extinction and the commonly used time for half the extinction debt to be paid off (half-life), is crucial for conservation purposes. Currently, there is no agreement on the rate of relaxation and the factors that it depends on. Here we find that half-life increases with area for all groups examined in a large meta-analysis of extinction data. A common pattern emerges if we use average number of individuals per species before habitat loss as an area index: for mammals, birds, reptiles and plants, the relationship has an exponent close to a half. We also find that the time to first determined extinction is short and increases slowly with area.

Targeted habitat restoration can reduce extinction rates in fragmented forests

Significance Most species extinctions after habitat loss are delayed. Thus, there are important, yet insufficiently appreciated, opportunities to conserve species through habitat restoration. Here, we assess the impact of targeted habitat restoration on how long tropical bird species might persist in two tropical biodiversity hotspots—the Eastern Arc Mountains of Tanzania and the Atlantic Forest of Brazil. Persistence times could be increased up to 56-fold by regenerating forest among the largest and closest forest fragments at these two localities. Given the unusually large numbers of threatened and endemic species that occur in other biodiversity hotspots, opportunities to enhance species persistence through habitat restoration should be explored elsewhere. The Eastern Arc Mountains of Tanzania and the Atlantic Forest of Brazil are two of the most fragmented biodiversity hotspots. Species–area relationships predict that their habitat fragments will experience a substantial loss of species. Most of these extinctions will occur over an extended time, and therefore, reconnecting fragments could prevent species losses and allow locally extinct species to recolonize former habitats. An empirical relaxation half-life vs. area relationship for tropical bird communities estimates the time that it takes to lose one-half of all species that will be eventually lost. We use it to estimate the increase in species persistence by regenerating a forest connection 1 km in width among the largest and closest fragments at 11 locations. In the Eastern Arc Mountains, regenerating 8,134 ha of forest would create >316,000 ha in total of restored contiguous forest. More importantly, it would increase the persistence time for species by a factor of 6.8 per location or ∼2,272 years, on average, relative to individual fragments. In the Atlantic Forest, regenerating 6,452 ha of forest would create >251,000 ha in total of restored contiguous forest and enhance species persistence by a factor of 13.0 per location or ∼5,102 years, on average, relative to individual fragments. Rapidly regenerating forest among fragments is important, because mean time to the first determined extinction across all fragments is 7 years. We estimate the cost of forest regeneration at

The Ambangulu Forest, West Usambara Mountains, Tanzania: a threatened Eastern Arc forest

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Small Mammal Inventories in the East and West Usambara Mountains, Tanzania. 1. Study Areas, Methodologies, and General Results

49 million dollars. It could provide one of the highest returns on investment for biodiversity conservation worldwide.