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1.
Ecol Evol ; 12(7): e9115, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35866020

RESUMO

Biomarkers of oxidative stress (OS) are useful in addressing a wide range of research questions, but thus far, they have had limited application to wild mammal populations due to a reliance on blood or tissue sampling. A shift toward non-invasive measurement of OS would allow field ecologists and conservationists to apply this method more readily. However, the impact of methodological confounds on urinary OS measurement under field conditions has never been explicitly investigated. We combined a cross-sectional analysis with a field experiment to assess the impact of four potential methodological confounds on OS measurements: (1) time of sampling, (2) environmental contamination from foliage; (3) delay between sample collection and flash-freezing in liquid nitrogen; and (4) sample storage of up to 15 months below -80°C. We measured DNA oxidative damage (8-hydroxy-2'-deoxyguanosine, 8-OHdG), lipid peroxidation (malondialdehyde, MDA), total antioxidant capacity (TAC), and uric acid (UA) in 167 urine samples collected from wild Zanzibar red colobus (Piliocolobus kirkii). We found that MDA was higher in samples collected in the morning than in the afternoon but there were no diurnal patterns in any of the other markers. Contamination of samples from foliage and length of time frozen at -80°C for up to 15 months did not affect OS marker concentrations. Freezing delay did not affect OS levels cross-sectionally, but OS values from individual samples showed only moderate-to-good consistency and substantial rank-order reversals when exposed to different freezing delays. We recommend that diurnal patterns of OS markers and the impact of storage time before and after freezing on OS marker concentrations be considered when designing sampling protocols. However, given the high stability we observed for four OS markers subject to a variety of putative methodological confounds, we suggest that urinary OS markers provide a valuable addition to the toolkit of field ecologists and conservationists within reasonable methodological constraints.

2.
J Biogeogr ; 49(5): 979-992, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35506011

RESUMO

Aim: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). Location: Global. Taxon: All extant mammal species. Methods: Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). Results: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use. Main conclusion: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

3.
Am J Primatol ; 83(12): e23338, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34662462

RESUMO

Species distributions are influenced by processes occurring at multiple spatial scales. It is therefore insufficient to model species distribution at a single geographic scale, as this does not provide the necessary understanding of determining factors. Instead, multiple approaches are needed, each differing in spatial extent, grain, and research objective. Here, we present the first attempt to model continent-wide great ape density distribution. We used site-level estimates of African great ape abundance to (1) identify socioeconomic and environmental factors that drive densities at the continental scale, and (2) predict range-wide great ape density. We collated great ape abundance estimates from 156 sites and defined 134 pseudo-absence sites to represent additional absence locations. The latter were based on locations of unsuitable environmental conditions for great apes, and on existing literature. We compiled seven socioeconomic and environmental covariate layers and fitted a generalized linear model to investigate their influence on great ape abundance. We used an Akaike-weighted average of full and subset models to predict the range-wide density distribution of African great apes for the year 2015. Great ape densities were lowest where there were high Human Footprint and Gross Domestic Product values; the highest predicted densities were in Central Africa, and the lowest in West Africa. Only 10.7% of the total predicted population was found in the International Union for Conservation of Nature Category I and II protected areas. For 16 out of 20 countries, our estimated abundances were largely in line with those from previous studies. For four countries, Central African Republic, Democratic Republic of the Congo, Liberia, and South Sudan, the estimated populations were excessively high. We propose further improvements to the model to overcome survey and predictor data limitations, which would enable a temporally dynamic approach for monitoring great apes across their range based on key indicators.


Assuntos
Hominidae , África Central , África Ocidental , Animais , República Centro-Africana , Coleta de Dados , Gorilla gorilla , Pan troglodytes
4.
Mar Pollut Bull ; 125(1-2): 360-366, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28958441

RESUMO

Destructive fishing using explosives occurs in a number of countries worldwide, negatively impacting coral reefs and fisheries on which millions of people rely. Documenting, quantifying and combating the problem has proved problematic. In March-April 2015 231h of acoustic data were collected over 2692km of systematically laid transects along the entire coast of Tanzania. A total of 318 blasts were confirmed using a combination of manual and supervised semi-autonomous detection. Blasts were detected along the entire coastline, but almost 62% were within 80km of Dar es Salaam, where blast frequency reached almost 10blasts/h. This study is one of the first to use acoustic monitoring to provide a spatial assessment of the intensity of blast fishing. This can be a useful tool that can provide reliable data to define hotspots where the activity is concentrated and determine where enforcement should be focused for maximum impact.


Assuntos
Aquicultura/métodos , Conservação dos Recursos Naturais , Explosões , Peixes , Acústica , Animais , Recifes de Corais , Substâncias Explosivas , Tanzânia
5.
Conserv Biol ; 30(4): 716-23, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26681228

RESUMO

Tanzania, arguably mainland Africa's most important nation for conservation, is losing habitat and natural resources rapidly. Moving away from a charcoal energy base and developing sustainable finance mechanisms for natural forests are critical to slowing persistent deforestation. Addressing governance and capacity deficits, including law enforcement, technical skills, and funding, across parts of the wildlife sector are key to effective wildlife protection. These changes could occur in tandem with bringing new models of natural resource management into play that include capacity building, corporate payment for ecosystem services, empowering nongovernmental organizations in law enforcement, greater private-sector involvement, and novel community conservation strategies. The future of Tanzania's wildlife looks uncertain-as epitomized by the current elephant crisis-unless the country confronts issues of governance, embraces innovation, and fosters greater collaboration with the international community.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Florestas , Animais , Ecossistema , Tanzânia
6.
PLoS One ; 9(12): e114154, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25469888

RESUMO

Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , África , Agricultura , Animais , Animais Selvagens , Ecossistema , Incêndios , Clima Tropical
7.
J Hum Evol ; 60(6): 731-45, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21458844

RESUMO

Since its discovery and description, the systematic position of the kipunji (Rungwecebus kipunji) has been a matter of debate. Although it was first placed in the mangabey genus Lophocebus, subsequent molecular studies indicated that the kipunji is most closely related to baboons (Papio). However, the kipunji does not appear to possess cranial features typical of Papio, thus necessitating the erection of a new genus, Rungwecebus. The recovery of an M2-stage subadult male kipunji voucher specimen, in addition to the original M1-stage subadult male voucher specimen, has since allowed further study. Here, we describe the craniodental morphology of the newly acquired kipunji specimen and present a phylogenetic analysis of Rungwecebus craniodental morphology using quantitative and qualitative characters. We examined the skulls of 76 M1- and M2-stage subadult males representing all extant papionin genera, taking note of character states that are static throughout ontogeny. To control for ontogenetic changes, only those characters expressing unchanged character states between subadult and adult specimens were coded for Rungwecebus and entered into a larger, recently published 151-character matrix of adult male morphology. To account for allometry, the narrow allometric coding method and the general allometric coding method were applied. The resulting most parsimonious trees suggest that Rungwecebus is phylogenetically closest to Lophocebus, a result consistent with initial morphological descriptions. However, due to the large amount of missing data for Rungwecebus, there are low bootstrap support values associated with any relationships within the larger Theropithecus/Papio/Lophocebus/Rungwecebus grouping. Taken in combination with previous molecular, phenetic, and ecological studies, the results of this study suggest that Rungwecebus is best regarded as a distinct genus closely related to Papio, Lophocebus, and Theropithecus. Adult morphological specimens are necessary to fully understand the adult kipunji morphotype, and its phylogenetic position will only be more precisely resolved with additional morphological and molecular data.


Assuntos
Cercopithecinae/anatomia & histologia , Filogenia , Crânio/anatomia & histologia , Dente/anatomia & histologia , Animais , Cefalometria , Cercopithecinae/classificação , Cercopithecinae/crescimento & desenvolvimento , Masculino , Odontometria , Crânio/crescimento & desenvolvimento , Dente/crescimento & desenvolvimento
8.
Primates ; 51(3): 213-20, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20204672

RESUMO

The diet and feeding behaviour of the kipunji (Rungwecebus kipunji) was studied over 45 months, the first dietary analysis for this species. During 9498 h of direct observation of 34 kipunji groups, a list of 122 identified foodplants was recorded. The list represents 60 families, including 64 trees, 30 herbs, 9 climbers, 7 shrubs, 6 lianas, 3 grasses and 3 ferns. Kipunji were observed eating bark, young and mature leaves, ripe and unripe fruits, flowers, pith, seed pods, rhizomes, tubers, shoots and stalks. Invertebrates, fungi, moss, lichen, and soil were also eaten. Macaranga capensis var. capensis, an early successional tree, was the most commonly consumed species, with leaves, leaf stalks, pith, flowers and bark all eaten. We demonstrate that the kipunji is an omnivorous dietary generalist, favouring mature and immature leaves, ripe and unripe fruits and bark in similar proportions, with an almost comparable fondness for leaf stalks and flowers. Kipunji appear to be adaptable foragers able to modify their diet seasonally, being more folivorous in the dry season and more frugivorous in the wet. Whereas more ripe fruit is eaten in the wet season, the proportion of unripe fruit remains similar across the year. The proportion of mature leaves and pith increases throughout the dry season at the expense of ripe fruits and bark, and this may compensate nutritionally for the lack of available dry-season ripe fruits. Relatively more pith is eaten in the dry season, more stalks at the end of the dry and beginning of the wet seasons, and bark consumption increases as the rainfall rises.


Assuntos
Cercopithecinae/fisiologia , Dieta , Comportamento Alimentar/fisiologia , Animais , Ecossistema , Invertebrados , Plantas , Tanzânia
9.
Biol Lett ; 6(2): 233-7, 2010 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-19906681

RESUMO

In the four years since its original description, the taxonomy of the kipunji (Rungwecebus kipunji), a geographically restricted and critically endangered African monkey, has been the subject of much debate, and recent research suggesting that the first voucher specimen of Rungwecebus has baboon mitochondrial DNA has intensified the controversy. We show that Rungwecebus from a second region of Tanzania has a distinct mitochondrial haplotype that is basal to a clade containing all Papio species and the original Rungwecebus voucher, supporting the placement of Rungwecebus as the sister taxon of Papio and its status as a separate genus. We suggest that the Rungwecebus population in the Southern Highlands has experienced geographically localized mitochondrial DNA introgression from Papio, while the Ndundulu population retains the true Rungwecebus mitochondrial genome.


Assuntos
Cercopithecinae/genética , DNA Mitocondrial/genética , Demografia , Fluxo Gênico/genética , Genética Populacional , Hibridização Genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Cercopithecinae/classificação , Biologia Computacional , Haplótipos/genética , Modelos Genéticos , Dados de Sequência Molecular , Papio/genética , Análise de Sequência de DNA , Tanzânia
11.
Science ; 312(5778): 1378-81, 2006 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-16690815

RESUMO

A new species of African monkey, Lophocebus kipunji, was described in 2005 based on observations from two sites in Tanzania. We have since obtained a specimen killed by a farmer on Mount Rungwe, the type locality. Detailed molecular phylogenetic analyses of this specimen demonstrate that the genus Lophocebus is diphyletic. We provide a description of a new genus of African monkey and of the only preserved specimen of this primate. We also present information on the animal's ecology and conservation.


Assuntos
Cercopithecinae/classificação , Animais , Cercopithecinae/anatomia & histologia , Conservação dos Recursos Naturais , Ecologia , Masculino , Tanzânia
12.
Science ; 308(5725): 1161-4, 2005 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-15905399

RESUMO

A distinct species of mangabey was independently found at two sites 370 kilometers apart in southern Tanzania (Mount Rungwe and Livingstone in the Southern Highlands and Ndundulu in the Udzungwa Mountains). This new species is described here and given the name "highland mangabey" Lophocebus kipunji sp. nov. We place this monkey in Lophocebus, because it possesses noncontrasting black eyelids and is arboreal. L. kipunji is distinguished from other mangabeys by the color of its pelage; long, upright crest; off-white tail and ventrum; and loud call. This find has implications for primate evolution, African biogeography, and forest conservation.


Assuntos
Cercocebus/classificação , Altitude , Animais , Biodiversidade , Tamanho Corporal , Cercocebus/anatomia & histologia , Conservação dos Recursos Naturais , Meio Ambiente , Geografia , Masculino , Densidade Demográfica , Tanzânia , Temperatura , Terminologia como Assunto , Árvores , Vocalização Animal
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