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1.
Ecol Evol ; 13(9): e10439, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37664503

RESUMEN

Forest transformation has major impacts on biodiversity and ecosystem functioning. Identifying the influence of forest habitat structure and composition on avian functional communities is important for conserving and managing forest systems. This study investigated the effect of forest structure and composition characteristics on bird species community structure, habitat use and functional diversity in 14 Mistbelt Forest patches of the Midlands of KwaZulu-Natal in South Africa. We surveyed bird communities using point counts. We quantified bird functional diversity for each forest patch using three diversity indices: functional richness, functional evenness and functional divergence. We further assessed species-specific responses by focussing on three avian forest specialists, orange ground-thrush Geokichla gurneyi, forest canary Crithagra scotops and Cape parrot Poicephalus robustus. We found that bird community and forest-specialist species responses to forest structure and tree species diversity differed. Also, forest structural complexity, canopy cover and tree species richness were the main forest characteristics better at explaining microhabitat influence on bird functional diversity. Forest patches with relatively high structural complexity and tree species richness had higher functional richness. Different structural characteristics influenced habitat use by the three forest specialists. Tree species diversity influenced C. scotops and G. gurneyi positively, while P. robustus responded negatively to forest patches with high tree species richness. Our study showed that site-scale forest structure and composition characteristics are important for bird species richness and functional richness. Forest patches with high tree species diversity and structural complexity should be maintained to conserve forest specialists, bird species richness and functional richness.

2.
Ambio ; 52(3): 598-615, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36583831

RESUMEN

Conservationists speculated on potential benefits to wildlife of lockdown restrictions because of the COVID-19 pandemic but voiced concern that restrictions impeded nature conservation. We assessed the effects of lockdown restrictions on biodiversity conservation in South Africa, a biodiverse country with economic inequality and reliance on wildlife resources. We solicited expert opinion using the IUCN's Threats Classification Scheme to structure a questionnaire and illustrated responses with individual case studies from government parastatal and non-governmental conservation organisations. The most highly reported threats were biological resource use, residential/commercial developments, invasive species, and human intrusions. The trends reported by 90 survey respondents were supported by case studies using environmental compliance data from parastatal conservation organisations. Lack of tourism revenue and funding were cited as hindrances to conservation. Mechanisms to prevent environmental degradation in the face of global emergencies must be implemented and 'ring-fenced' to ensure conservation is not a casualty during future global crises.


Asunto(s)
COVID-19 , Conservación de los Recursos Naturales , Animales , Humanos , Animales Salvajes , Control de Enfermedades Transmisibles/legislación & jurisprudencia , COVID-19/prevención & control , Sudáfrica , Encuestas y Cuestionarios
4.
Ambio ; 50(10): 1866-1878, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33677809

RESUMEN

Urbanisation is rapidly transforming natural landscapes with consequences for biodiversity. Little is documented on the response of African wildlife to urbanisation. We reviewed case studies of vertebrate species' responses to urbanisation in KwaZulu-Natal, South Africa to determine trends. Connected habitat mosaics of natural and anthropogenic green spaces are critical for urban wildlife persistence. We present a novel modification to the final of three phases of the framework described by Evans et al. (2010), which documents this sequence for vertebrate species persistence, based on the perspective of our research. Species in suburbia exhibit an initial phase where behavioural and ecological flexibility, life-history traits and phenotypic plasticity either contribute to their success, or they stay at low numbers. Where successful, the next phase is a rapid increase in populations and distribution; anthropogenic food resources and alternate breeding sites are effectively exploited. The modified third phase either continues to spread, plateau or decline.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Conservación de los Recursos Naturales , Sudáfrica , Urbanización , Vertebrados
5.
J Environ Manage ; 284: 112041, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33540193

RESUMEN

South Africa's communal rangelands constitute ~25% of the country's land cover and are largely managed for livestock grazing. These habitats play an important role in rural livelihoods and cultural practices. Using semi-structured interviews, we documented indigenous local ecological knowledge (LEK) held by rural dwellers linked to natural resource utilisation, environmental health and cultural keystone indicator species (CKIS) in the grassland communities of southern KwaZulu-Natal, South Africa. Our main objective was to examine the ability for LEK to inform conservation management. We found that people who were heavily reliant on natural resources attained a higher LEK score, indicating a greater breadth of ecological knowledge, which in turn shaped their perceptions of environmental change. Community members confirmed the presence of conservation concern species within this area, highlighting the limitations of only using citizen science databases for conservation management, as their observations within these databases are biased towards major road routes and protected or urban areas. LEK can play an important role in identifying habitats crucial to species' persistence and delineating population trends over time. Our surveys highlighted the importance of the Southern Ground-hornbill Bucorvus leadbeateri as a CKIS that acts as an early warning system of changing weather, notably rain. However, LEK is context-specific, and some CKIS species such as the Southern Ground-hornbill have wide distribution ranges. Consequently, the cultural associations and implications differ based on local belief systems that are often defined by the language spoken and the community's geographical location. Our study demonstrated the importance of including indigenous LEK in conservation planning for threatened species and habitats and the importance of traditional family values responsible for transferring oral knowledge.


Asunto(s)
Aves , Conservación de los Recursos Naturales , Animales , Ecología , Ecosistema , Humanos , Conocimiento , Sudáfrica
6.
Ambio ; 49(6): 1211-1221, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31564051

RESUMEN

A horizon scan was conducted to identify emerging and intensifying issues for biodiversity conservation in South Africa over the next 5-10 years. South African biodiversity experts submitted 63 issues of which ten were identified as priorities using the Delphi method. These priority issues were then plotted along axes of social agreement and scientific certainty, to ascertain whether issues might be "simple" (amenable to solutions from science alone), "complicated" (socially agreed upon but technically complicated), "complex" (scientifically challenging and significant levels of social disagreement) or "chaotic" (high social disagreement and highly scientifically challenging). Only three of the issues were likely to be resolved by improved science alone, while the remainder require engagement with social, economic and political factors. Fortunately, none of the issues were considered chaotic. Nevertheless, strategic communication, education and engagement with the populace and policy makers were considered vital for addressing emerging issues.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Política , Sudáfrica
7.
Folia Primatol (Basel) ; 90(3): 190-198, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30889599

RESUMEN

We report the first in-depth evidence of targeted mushroom foraging in an Asian colobine. Using direct observations (2010-2018) and camera traps (2008-2018) in the Sebangau Forest, Central Kalimantan, Indonesian Borneo, we show how adult female red langurs (Presbytis rubicunda) are regularly descending to the ground to consume mushrooms. We recorded 82 counts (0.36% of all focal observations, n = 25,502) of the focal adult langur on the ground from direct observations of habituated groups, and 80 independent images/videos of red langurs on the ground were obtained from the camera traps representing 1.12% of total images (n = 7,145). Mushroom consumption took place in 4 families, representing 0.04% of total focal behaviour observations and 24.3% of total time feeding on the ground. From the camera trap photos, red langurs are spending 20% of time on the ground feeding. We speculate that mushrooms could be a supplementary food for adult female langurs as there is an increase in consumption in April and November.


Asunto(s)
Agaricales , Colobinae/fisiología , Conducta Alimentaria , Animales , Borneo , Cercopithecidae/fisiología , Femenino , Indonesia , Masculino
8.
Behav Processes ; 159: 9-22, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30552995

RESUMEN

Understanding the effects of anthropogenic disturbance on species' behaviour is crucial for conservation planning, considering the extent of habitat loss. We investigated the influence of anthropogenic disturbances including agriculture, urbanisation, protected areas, and the presence of novel predators, on the temporal and spatial behaviour of sympatric forest antelope (Tragelaphus scriptus, Philantomba monticola, Sylvicapra grimmia, and Cephalophus natalensis) in an anthropogenic matrix containing forest fragments in the Indian Ocean Coastal Belt of South Africa. We integrated land-use types with camera-trap data and compared activity patterns using circular statistics and occupancy modelling. Antelope species overlapped in temporal and spatial distribution and exhibited diurnal activity for 50% of the time. All species exhibited nocturnal activity for ∼25-33% of all observations, except for C. natalensis. Nocturnal activity varied between species and land-use types. The predators Canis familiaris, C. mesomelas and Caracal caracal negatively influenced occupancy of P. monticola, S. grimmia and C. natalensis. Humans negatively influenced temporal activity of P. monticola, and spatial distribution of T. scriptus and S. grimmia. C. familiaris had an overall negative influence on S. grimmia. We found spatial, and to a lesser extent temporal, segregation between species. However, plasticity in activity patterns existed, which varied in response to anthropogenic effects and novel predators.


Asunto(s)
Antílopes , Ritmo Circadiano , Bosques , Actividades Humanas , Locomoción , Conducta Predatoria , Animales , Ecosistema , Ambiente , Humanos , Sudáfrica , Análisis Espacio-Temporal , Especificidad de la Especie
9.
Folia Primatol (Basel) ; 85(5): 265-76, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25377754

RESUMEN

We provide the first parasite assessment of wild red langurs (Presbytis rubicunda). Seven helminth taxa and 4 protozoa were recovered from faecal samples. We report the details of the death of an adult female red langur with potential association of an elevated parasite infection. There is a paucity of published literature on red langurs and nothing is known of the factors affecting interspecific parasite transmission and disease spread between other primate species. Parasites may be substantial determinants of host health and may present a significant influence on the survival and reproduction of individuals and the subsequent fecundity of populations. Further research into the connection of parasite burden with individual deaths and potential population declines is recommended for monitoring population health.


Asunto(s)
Cercopithecidae , Helmintiasis Animal/epidemiología , Enfermedades de los Monos/epidemiología , Infecciones Protozoarias en Animales/epidemiología , Amébidos/aislamiento & purificación , Animales , Balantidium/aislamiento & purificación , Borneo/epidemiología , Heces/parasitología , Femenino , Helmintiasis Animal/mortalidad , Helmintiasis Animal/parasitología , Indonesia/epidemiología , Masculino , Enfermedades de los Monos/mortalidad , Enfermedades de los Monos/parasitología , Nematodos/aislamiento & purificación , Prevalencia , Infecciones Protozoarias en Animales/mortalidad , Infecciones Protozoarias en Animales/parasitología , Trematodos/aislamiento & purificación
10.
Am J Primatol ; 75(8): 848-59, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23553789

RESUMEN

Southeast Asia's lowland dipterocarp forests experience supra-annual "mast" fruiting and flowering events, in which the majority of trees reproduce simultaneously at irregular intervals, with extensive intervening periods of very low primate food availability. This scarcity of food results in a negative energy balance and a reliance on "fallback foods" in some primate species. By contrast, ombrogenous tropical peat-swamp forests are non-masting, and show lower variability of food availability. We sought to test the influence of fruit availability on primate diet and preference in peat-swamp habitats and assess whether it differs from masting forests. We collected behavioral-dependent feeding data on three adult females in a group of red langurs (Presbytis rubicunda: Colobinae) between January and December 2011 in Sabangau tropical peat-swamp forest, Central Kalimantan, Indonesia, as colobine monkeys are adaptated for folivory, and are therefore generally considered less reliant on temporally variable fruits than monogastric primates. We documented the highest level of granivory recorded to date in colobine monkeys: mean annual diet comprised 76.4% seeds and 7.3% other fruit parts; 7.7% young and 2.5% mature leaves; 2.8% flowers; 2.6% piths, and <1% on other minor food items. Fruit availability was fairly constant throughout the year and fruit parts were consumed at consistently higher levels than expected based on availability, confirming that fruit is preferred. Leaves and flowers were consumed consistently less than expected and thus are not preferred. There were no significant correlations between preferred food availability and consumption of potential fallback foods, suggesting that reliance on fallback foods did not occur in Sabangau during the study period. Furthermore, consumption of fruit was not significantly correlated with its availability. Our findings suggest that the relatively constant availability of fruit in this habitat affords P. rubicunda regular access to a nutritionally superior food, and that reliance on fallback foods is therefore not required.


Asunto(s)
Cercopithecidae/fisiología , Ecosistema , Conducta Alimentaria/fisiología , Árboles , Animales , Borneo , Dieta , Femenino , Preferencias Alimentarias , Masculino
11.
Am J Primatol ; 75(8): 837-47, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23526631

RESUMEN

Because of the large-scale destruction of Borneo's rainforests on mineral soils, tropical peat-swamp forests (TPSFs) are increasingly essential for conserving remnant biodiversity, particularly in the lowlands where the majority of habitat conversion has occurred. Consequently, effective strategies for biodiversity conservation are required, which rely on accurate population density and distribution estimates as a baseline. We sought to establish the first population density estimates of the endemic red langur (Presbytis rubicunda) in Sabangau TPSF, the largest remaining contiguous lowland forest-block on Borneo. Using Distance sampling principles, we conducted line transect surveys in two of Sabangau's three principle habitat sub-classes and calculated group density at 2.52 groups km⁻² (95% CI 1.56-4.08) in the mixed-swamp forest sub-class. Based on an average recorded group size of 6.95 individuals, population density was 17.51 ind km⁻², the second highest density recorded in this species. The accessible area of the tall-interior forest, however, was too disturbed to yield density estimates representative of the entire sub-class, and P. rubicunda was absent from the low-pole forest, likely as a result of the low availability of the species' preferred foods. This absence in 30% of Sabangau's total area indicates the importance of in situ population surveys at the habitat-specific level for accurately informing conservation strategies. We highlight the conservation value of TPSFs for P. rubicunda given the high population density and large areas remaining, and recommend 1) quantifying the response of P. rubicunda to the logging and burning of its habitats; 2) surveying degraded TPSFs for viable populations, and 3) effectively delineating TPSF sub-class boundaries from remote imagery to facilitate population estimates across the wider peat landscape, given the stark contrast in densities found across the habitat sub-classes of Sabangau.


Asunto(s)
Cercopithecidae/fisiología , Ecosistema , Árboles , Clima Tropical , Animales , Femenino , Indonesia , Masculino , Densidad de Población , Estaciones del Año
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