habitat fragmentation Archives - Resilient Landscapes

Changes in elephant movements in the Western Wildlife Corridor, Ghana

Key messages

The savannahs of northern Ghana were historically an important habitat for elephants.
The Western Wildlife Corridor (WWC) was identified in 2007 as one of the two main elephant migratory corridors between northern Ghana and southern Burkina Faso.
The WWC encompasses over 100 villages; livelihood activities in these villages include farming, livestock keeping, small-scale mining and fuelwood extraction, which are putting pressure on resources.
Elephant presence and movement in the corridor became sporadic in the 1970s with increasing habitat fragmentation and hunting pressure.
Elephants have changed their routes in the corridor since the 2000s, and now tend to move along the channels of rivers and their tributaries.
Farmland expansion and livestock grazing are the two most important factors that have forced elephants to change their routes.
Establishment of a continuum of effective community resource management areas (CREMAs)a throughout the WWC may restore its function as an effective corridor for elephants.

Community forests as beacons of conservation: Enabling local populations monitor their biodiversity

Habitat fragmentation is one of the main threats to biodiversity in Africa. In this article, we highlight the importance of conserving the Guinean forests of West Africa, which are rich in biodiversity and endemism but threatened by habitat loss, degradation and fragmentation. The size of forest patches is critical, with larger fragments containing more species than smaller ones. The protection of intact, dense forest patches is vital for any conservation strategy in West Africa, but improving the management of forests that are already used for logging and hunting is also essential. Community forests (CFs) can play a crucial role in conservation, especially if there is a substantial network that can promote ecological connectivity. However, biomonitoring in CFs remains a challenge due to inadequate resources. By developing standardised, easy-to-apply and inexpensive methods for biomonitoring, communities can be involved in biomonitoring instead of relying solely on scientists and expensive equipment. We present a monitoring framework here where we suggest local communities should become the main agents for biomonitoring in their own forests; we highlight a five-step scheme. The importance of the various CFs in terms of conservation should be made through a combination of accurate, standardised face-to-face interviews with selected persons in the target communities and biomonitoring be based on the RAPELD scheme. The latter will be implemented after specifically training local ‘wise’ persons. We are proposing a kind of ‘citizen science’ scheme, applied to enhance the ability of local communities to monitor their own biodiversity.

Looking for indicator bird species in the context of forest fragmentation and isolation in West Kalimantan, Indonesia

In the context of Borneo’s drastic landscape fragmentation, we assessed the role of diverse forest and land uses—swidden agriculture, mixed garden, smallholder rubber and oil palm plantations—in determining (1) diversity levels and composition of bird species in different vegetation types; (2) the potential for bird species to act as indicators of habitat quality; and (3) the agricultural matrix’s contribution to preserving forest-dependent species. Field campaigns across West Kalimantan sites were conducted during both rainy and dry seasons, using mist nets and 10-min point count recordings along transects. We used four diversity indices, non-metric multidimensional scaling (NMDS) and the Indicator Value index (IndVal) for our analysis. Our results endorsed the general trend found across the tropics of a significant reduction in bird species richness, from the complex natural and old secondary forest structures to the simplified monoculture habitats. We recorded 10,519 individuals across 214 bird species, representing almost 90% of Borneo’s lowland forest species. NMDS differentiated intact forest from forest fragments and land under different agriculture uses. Eighty percent of the bird species preferred an intact forest environment. Industrial oil palm sites were the most ‘avoided’ vegetation type. Using IndVal, we found six indicator species significantly associated with forest, three indicator species for depleted forest, one for mixed garden, and none for oil palm plantation. Farm-dependent species richness was strikingly low, and species had little conservation value as per IUCN standards; industrial oil palm plantations were poorest in bird species. Notable exceptions were traditional mixed gardens and old fallows associated with swidden agriculture, when in proximity to forest. These traditional agroforestry systems have higher conservation value than industrial and smallholder monoculture plantations, however, their long-term preservation is uncertain, and monitoring programs are lacking that can contribute to long-term biodiversity conservation and ecosystem service maintenance. More data are needed to determine the viable population sizes for the bird indicator species identified in our study. Such knowledge on population trends can be used to monitor habitat quality and health of forest agriculture landscape mosaics and improve the effectiveness of management, conservation and monitoring in future.

Continuous resin tapping for frankincense harvest increases susceptibility of Boswellia papyrifera (Del.) Hochst trees to longhorn beetle damage

Frankincense is an important tree resin that provides a livelihood in the semi-arid lower highlands of East Africa. In the absence of sustainable management strategies, Boswellia papyrifera trees were being overexploited, leading to a depletion of genetic diversity, affected by pests and diseases, failure in natural regeneration, and hence a subsequent decline in socio-ecological benefits obtained from the species. We studied the impact of (i) continuous resin tapping without resting years and (ii) tapping or wonding intensity for frankincence production on the prevalence of longhorn beetle (Idactus spinipennis Gahan, Cerambycidae (sub family Lamiinae) damage in northern Ethiopia. We found that continuous resin tapping for frankincense harvest without adequate resting period made trees more vulnerable to longhorn beetle damage (P < 0.05). Trees rested for 10 and more years from resin tapping had less beetle damage occurrence than those tapped continuously (P < 0.05). Stem tapping intensity of more than 12 wounds per tree in one frankincense harvesting season caused high longhorn beetle damage incidence in Central Tigray (up to 90%) and Western Tigray (up to 80%). We recommend that B. papyrifera trees should have a resting period of at least 3 years and more after one year of continuous tapping. Depending on the size of a tree, wounding for frankincense harvest should be restricted to less than 12 wounds per tree. These measures would help the species develop resistance to longhorn beetle attack and maintain a healthy population for sustainable provision of ecosystem services including frankincense production in the dryalnds of northern Ethiopia. Dryland; Habitat fragmentation; Idactus spinipennis; Cerambycidae; Frankincense; Dry woodland, Ethiopia

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