22 research outputs found
Degree of egg-taking by humans determines the fate of maleo (Macrocephalon maleo) nesting grounds across Sulawesi
The version of record of this article, first published in Biodiversity and Conservation, is available online at Publisher’s website: http://dx.doi.org/10.1007/s10531-022-02527-1The maleo (Macrocephalon maleo) of Sulawesi, Indonesia, is culturally iconic and Critically Endangered, but the causes of its decline have never been systematically analyzed nor its nesting grounds comprehensively surveyed. We visited 122 previously known and 58 previously unrecorded sites, collecting data and interviewing local people at each site. We used ordinal logistic regression to fit models with combinations of 18 different predation, habitat, and nesting ground variables to determine the strongest predictors of nesting ground success, as represented by maleo numbers. At least 56% of known nesting grounds are now inactive (abandoned), and 63% of remaining active sites host ≤ 2 pairs/day at peak season. Egg-taking by humans is the single biggest driver of maleo decline. Protecting eggs in situ predicts higher numbers than protecting eggs through hatchery methods. After egg-taking, quality (not length) of the travel corridor connecting nesting ground to primary forest best predicts nesting ground success. Being inside a federally protected area is not a primary driver of success, and does not ensure persistence: 28% of federally protected nesting grounds have become inactive. Local conservation efforts protected nesting grounds 2‒3 times
better than federal protection. We update the methodology for assessing nesting ground status, and recommend five measures for maleo conservation, the foremost being to protect nesting grounds from egg-taking by humans at all remaining active sites
Severity of deforestation mediates biotic homogenisation in an island archipelago
Anthropogenic-driven species extinctions are radically changing the biosphere. Biological communities may become increasingly similar to or dissimilar from one another via the processes of biotic homogenisation or heterogenisation. A key question is how the conversion of native forests to agriculture may influence these processes by driving changes in the occurrence patterns of restricted-range endemic species versus wide-ranging generalists. We examined biotic homogenisation and heterogenisation in bird communities on the Southeast Asian islands of Borneo, Sulawesi, Seram, Buru, Talaud and Sangihe. Each island is characterised by high levels of avian endemism, and unique spatial configuration of forest conversion to agriculture. Forest conversion to agriculture influenced the patterns of biotic homogenisation on five islands. Bird communities became increasingly dissimilar to forest reference communities relative to localised patterns of deforestation. Turnover led to species with larger global range-sizes dominating communities at the expense of island endemics and ecological specialists. Within islands, forest conversion did not result in clear changes to β-diversity, whereas between-island communities became increasingly similar with greater deforestation, implying that patterns of forest conversion profoundly affect biotic homogenisation. Our findings elucidate how continued conversion of forests is causing the replacement of endemic species by a small cohort of shared ubiquitous species with potentially strong negative consequences for ecosystem functioning and resilience. Halting reorganisation of the biosphere via the loss of range-restricted species and spread of wide-ranged generalists will require improved efforts to reduce the impacts of deforestation particularly in regions with high endemism
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Emerging threats from deforestation and forest fragmentation in the Wallacea centre of endemism
The Wallacea biogeographic region of Sulawesi, the Moluccas and Lesser Sunda, is globally renowned for exceptional endemism, but is currently emerging as a development frontier in Indonesia. We assessed patterns and drivers of forest loss and fragmentation across the region, and used dynamic deforestation models to project future deforestation to 2053. Up to 10,231 km2 was deforested between 2000 and 2018, and a further 49,570 km2 is expected to be lost by 2053, with annual deforestation rates ranging between 0.09% and 2.17% in different sub-regions (average: 1.23%). Key Biodiversity Areas (priority sites for endemic and threatened biodiversity) are particularly vulnerable to deforestation if they are small, coastal and unprotected. Sub-regional variation in deforestation patterns and drivers must be acknowledged if conservation interventions are to be targeted and effective. We provide a valuable baseline from which to monitor Wallacea’s new development course, as Indonesia undergoes profound policy changes that will provide both challenges and opportunities for environmental governance and conservation
Safeguarding Imperiled Biodiversity and Evolutionary Processes in the Wallacea Center of Endemism
Wallacea—the meeting point between the Asian and Australian fauna—is one of the world's largest centers of endemism. Twenty-three million years of complex geological history have given rise to a living laboratory for the study of evolution and biodiversity, highly vulnerable to anthropogenic pressures. In the present article, we review the historic and contemporary processes shaping Wallacea's biodiversity and explore ways to conserve its unique ecosystems. Although remoteness has spared many Wallacean islands from the severe overexploitation that characterizes many tropical regions, industrial-scale expansion of agriculture, mining, aquaculture and fisheries is damaging terrestrial and aquatic ecosystems, denuding endemics from communities, and threatening a long-term legacy of impoverished human populations. An impending biodiversity catastrophe demands collaborative actions to improve community-based management, minimize environmental impacts, monitor threatened species, and reduce wildlife trade. Securing a positive future for Wallacea's imperiled ecosystems requires a fundamental shift away from managing marine and terrestrial realms independently
Safeguarding Imperiled Biodiversity and Evolutionary Processes in the Wallacea Center of Endemism
Wallacea—the meeting point between the Asian and Australian fauna—is one of the world's largest centers of endemism. Twenty-three million years of complex geological history have given rise to a living laboratory for the study of evolution and biodiversity, highly vulnerable to anthropogenic pressures. In the present article, we review the historic and contemporary processes shaping Wallacea's biodiversity and explore ways to conserve its unique ecosystems. Although remoteness has spared many Wallacean islands from the severe overexploitation that characterizes many tropical regions, industrial-scale expansion of agriculture, mining, aquaculture and fisheries is damaging terrestrial and aquatic ecosystems, denuding endemics from communities, and threatening a long-term legacy of impoverished human populations. An impending biodiversity catastrophe demands collaborative actions to improve community-based management, minimize environmental impacts, monitor threatened species, and reduce wildlife trade. Securing a positive future for Wallacea's imperiled ecosystems requires a fundamental shift away from managing marine and terrestrial realms independently