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1.
Am J Primatol ; 86(1): e23569, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37899689

ABSTRACT

Deforestation and habitat fragmentation is the primary threat to primate populations. The primates that live within degraded and anthropogenically disturbed habitats typical of fragmented landscapes have to cope with lower availability of resources in comparison to primates in continuous, undisturbed forests. While some species are sensitive to forest fragmentation, some evidence exists to suggest that primates can alter their behavior and adapt to such changes, which enables their survival in suboptimal habitat. In this study, we assessed how forest fragmentation and its associated edge-effects impact the feeding ecology and activity levels of a nocturnal primate community in the Sahamalaza-Iles Radama National Park, North West Madagascar. From March 06, 2019 to May 17, 2022, we collected data on tree and invertebrate phenology at our study site, and feeding ecology and activity for 159 lemur individuals from four species. Fruit and flower availability varied significantly between continuous and fragmented forest, and between forest core and edge areas, with continuous forest exhibiting higher continuous fruit and flower availability. Lemur feeding ecology varied significantly too, as the feeding niches of all four species were significantly different between continuous and fragmented forest and between core and edge areas. However, lemur activity levels were mostly consistent among all forest areas. The results of this study suggest that nocturnal lemurs are able to adapt their dietary ecology in response to the available food sources within their habitat. Due to this flexible ecology and dietary plasticity, the lemurs do not need to significantly alter their behavior in different environments to fulfill their dietary needs. While nocturnal lemurs demonstrate adaptability and flexibility to degraded habitat, it is unclear how far this plasticity will stretch considering that Madagascar's forests are still being cleared at an alarming rate. Urgent conservation action is therefore needed to ensure the future of lemur habitat.


Subject(s)
Lemur , Lemuridae , Strepsirhini , Animals , Lemur/physiology , Madagascar , Ecology , Lemuridae/physiology , Ecosystem , Forests
2.
Curr Zool ; 69(6): 694-702, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37876641

ABSTRACT

Male dominance hierarchies have been studied in many animals but rarely in bats (Chiroptera). The dominance rank of social animals may dictate access to resources and mates; therefore, it has important implications for an individual's fitness and is crucial for successful captive management. Between January and December 2018, at both Bristol Zoo Gardens (Bristol, UK) and Jersey Zoo (Jersey, British Isles), we observed 19 male Livingstone's fruit bats Pteropus livingstonii using focal follows for 345 h overall, noting the outcome of all agonistic interactions. We recorded instigators of interactions, along with winners and losers, and analyzed these data using the R-package "EloRating" to create Elo-rating temporal plots of dominance ranks. We used generalized linear mixed models and multiple linear regression to analyze interaction data and test hypotheses regarding predictors of dominance rank, frequency of agonistic interaction, and choice of interaction partner. Age was positively correlated with dominance rank up to around year 9, when an asymptote was attained. Highly ranked bats instigated the most agonistic interactions, and largely directed these interactions at bats with much lower rankings than themselves. Hierarchies were extremely stable throughout the data collection period at both sites. We conclude that Livingstone's fruit bats have a stable linear dominance hierarchy, with high-ranking, typically older males instigating the most interactions with lowest ranking males to secure dominance rank. This study adds to the limited discourse on Pteropus social behaviors, indicating that some bat species may have social systems similar in complexity to some nonhuman primates.

3.
Int J Primatol ; 43(1): 15-39, 2022.
Article in English | MEDLINE | ID: mdl-34744218

ABSTRACT

Over the past decades, primate populations have been declining. Four years ago, >60% of species were listed as threatened. As the rate of loss accelerates and new IUCN assessments are being published, we used IUCN Red List assessments and peer-reviewed literature published within the last 5 yr to evaluate the status of primates globally, by region and by taxonomic group. We also examined the main factors affecting a species' conservation status to determine if we could predict the status of understudied species. We found that 65% of species are in the top three IUCN Red List categories (Vulnerable, Endangered, Critically Endangered). Globally, the main threats to primates are Biological Resource Use, including Hunting & Logging, and Agriculture. The impact of these threats varied by region and taxon. Our model showed that Malagasy and Asian primates, and those affected by Agriculture, Human Disturbance, and Climate Change were more likely to be considered at risk of extinction. The model's predictive probability, however, was low. Our literature analysis showed that some threats, especially climate change and disease, affected more species than indicated by the IUCN Red List. As we move into the next decade, we must continue tackling hunting and agricultural expansion but also be vigilant about emerging threats. We must also aim to regularly test the effectiveness of mitigation strategies, evaluating their long-term adoption and their impact on primates; as well as to increase communication between researchers and applied conservationists to ensure IUCN assessments include current and emerging threats. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10764-021-00242-2.

4.
Am J Primatol ; 82(2): e23083, 2020 02.
Article in English | MEDLINE | ID: mdl-31912545

ABSTRACT

The Sanje mangabey (Cercocebus sanjei) is endemic to the Udzungwa Mountains, Tanzania, and is classified as Endangered due to its putatively declining population size, habitat degradation and fragmentation. Previous population size estimates have ranged from 1,350 to 3,500 individuals, with the last direct survey being conducted 15 years before the present study. Previous estimates are now thought to have underestimated the population due to a limited knowledge of group and habitat size, nonsystematic approaches and the use of visual methods that are not suitable for surveying the Sanje mangabey with its semi-terrestrial and elusive behaviors. We used an acoustic survey method with observers recording the distinctive "whoop-gobble" vocalization produced by mangabeys and point transect distance sampling to model a detection function and estimate abundance. Twenty-eight surveys were conducted throughout the two forests where Sanje mangabeys are found: Mwanihana forest in the Udzungwa Mountains National Park (n = 13), and the Uzungwa Scarp Nature Reserve (n = 15). Group density was found to be significantly lower in the relatively unprotected Uzungwa Scarp forest (0.15 groups/km2 ; 95% CI: 0.08-0.27) compared to the well-protected Mwanihana forest (0.29 groups/km2 ; 95% CI: 0.19-0.43; p = .03). We estimate that there are 1,712 (95% CI: 1,141-2,567) individuals in Mwanihana and 1,455 (95% CI: 783-2,702) in the Uzungwa Scarp, resulting in a total population size of 3,167 (95% CI: 2,181-4,596) individuals. The difference in group density between sites is likely a result of the differing protection status and levels of enforcement between the forests, suggesting that protection of the Uzungwa Scarp should be increased to encourage recovery of the population, and reduce the threat of degradation and hunting. Our results contribute to the reassessment of the species' IUCN Red List status and informing management and conservation action planning.


Subject(s)
Cercocebus , Conservation of Natural Resources , Acoustics/instrumentation , Animals , Conservation of Natural Resources/methods , Ecology/methods , Population Density , Tanzania
5.
BMJ Open ; 9(2): e024429, 2019 02 27.
Article in English | MEDLINE | ID: mdl-30819706

ABSTRACT

OBJECTIVE: Cognitive impairment is a pervasive outcome of stroke, reported in over half of patients 6 months post-stroke and is associated with increased disability and a poorer quality of life. Despite the prevalence of post-stroke cognitive impairment, the efficacy of existing psychological interventions for the rehabilitation of cognitive impairment following stroke has yet to be established. The aim of this study is to identify psychological interventions from non-randomised studies that intended to improve post-stroke cognitive function and establish their efficacy. DESIGN: Systematic review and meta-analysis of non-randomised studies of psychological interventions addressing post-stroke cognitive impairment. DATA SOURCES: Electronic searches were performed in the Pubmed, EMBASE and PsycINFO databases, the search dating from inception to February 2017. ELIGIBILITY CRITERIA: All non-randomised controlled studies and quasi-randomised controlled trials examining psychological interventions to improve cognitive function following stroke were included, such as feasibility studies, pilot studies, experimental studies, and quasi-experimental studies. The primary outcome was cognitive function. The prespecified secondary outcomes were functional abilities in daily life and quality of life. METHODS: The current meta-analyses combined the findings of seven controlled studies, examining the efficacy of psychological interventions compared with treatment-as-usual controls or active controls, and 13 one-group pre-post studies. RESULTS: Results indicated an overall small effect on cognition across the controlled studies (Hedges' g=0.38, 95% CI=0.06 to 0.7) and a moderate effect on cognition across the one-group pre-post studies (Hedges' g=0.51, 95% CI=0.3 to 0.73). Specific cognitive domains, such as memory and attention also demonstrated a benefit of psychological interventions. CONCLUSIONS: This review provides support for the potential of psychological interventions to improve overall cognitive function post-stroke. Limitations of the study, in terms of risk of bias and quality of included studies, and future research directions are explored. PROSPERO REGISTRATION NUMBER: CRD42017069714.


Subject(s)
Cognitive Dysfunction/etiology , Stroke/complications , Cognitive Dysfunction/rehabilitation , Cognitive Dysfunction/therapy , Humans , Psychotherapy
6.
BMJ Open ; 8(1): e019001, 2018 01 10.
Article in English | MEDLINE | ID: mdl-29326188

ABSTRACT

INTRODUCTION: Stroke is one of the primary causes of death and disability worldwide, leaving a considerable proportion of survivors with persistent cognitive and functional deficits. Despite the prevalence of poststroke cognitive impairment, there is no established treatment aimed at improving cognitive function following a stroke. Therefore, the aims of this systematic review are to identify psychological interventions intended to improve poststroke cognitive function and establish their efficacy. METHODS AND ANALYSIS: A systematic review of non-randomised controlled studies that investigated the efficacy of psychological interventions aimed at improving cognitive function in stroke survivors will be conducted. Electronic searches will be performed in the PubMed, Embase and PsycINFO databases, the search dating from the beginning of the index to February 2017. Reference lists of all identified relevant articles will be reviewed to identify additional studies not previously identified by the electronic search. Potential grey literature will be reviewed using Google Scholar. Titles and abstracts will be assessed for eligibility by one reviewer, with a random sample of 50% independently double-screened by second reviewers. Any discrepancies will be resolved through discussion, with referral to a third reviewer where necessary. Risk of bias will be assessed with the Risk of Bias in Non-randomized Studies of Interventions tool. Meta-analyses will be performed if studies are sufficiently homogeneous. This review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The quality of the evidence regarding cognitive function will be assessed according to the Grading of Recommendations Assessment, Development and Evaluation. ETHICS AND DISSEMINATION: This systematic review will collect secondary data only and as such ethical approval is not required. Findings will be disseminated through presentations and peer-reviewed publication. This review will provide information on the effectiveness of psychological interventions for poststroke cognitive impairment, identifying which psychological interventions are effective for improving poststroke cognitive function. PROSPERO REGISTRATION NUMBER: CRD42017069714.


Subject(s)
Cognition , Cognitive Dysfunction/therapy , Stroke Rehabilitation/methods , Stroke/complications , Cognitive Dysfunction/etiology , Cognitive Dysfunction/rehabilitation , Humans , Research Design , Stroke/psychology , Survivors , Systematic Reviews as Topic
7.
Int J Primatol ; 38(6): 1072-1089, 2017.
Article in English | MEDLINE | ID: mdl-29263564

ABSTRACT

Primates require secure sleeping sites for periods of rest, but despite their importance, the characteristics of desired sleeping sites are poorly known. Here we investigated the sleeping ecology of a radio-collared population of the Sambirano mouse lemur, Microcebus sambiranensis, during the nonreproductive season in the Anabohazo forest, northwestern Madagascar. We also investigated their ranging behavior and examined the spatial distribution of sleeping sites within the home ranges of the collared individuals. We took measurements of the sleeping tree's physical characteristics and recorded the number of collared individuals using each sleeping site. We found that M. sambiranensis generally use foliage sleeping sites more frequently than tree holes and individuals slept more frequently in densely foliated trees than in sparsely foliated trees, often alone. We observed no significant differences in home range size or nightly travel distance between males and females; however, home ranges were smaller than those described for other mouse lemur species. Finally, we found that M. sambiranensis sleep peripherally and forage centrally within their home ranges, a behavior not previously described for mouse lemurs. Our results indicate profound differences in the social organization between M. sambiranensis and other mouse lemur species described in the literature, suggesting species-specificity in mouse lemur ecology. Understanding the sleeping ecology and ranging behavior of mouse lemurs is of great importance to their conservation, as these data facilitate the planning of long-term reforestation, habitat management, and population assessment.

8.
Cochrane Database Syst Rev ; 9: CD004479, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28881006

ABSTRACT

BACKGROUND: For management of pneumothorax that occurs without underlying lung disease, also referred to as primary spontaneous pneumothorax, simple aspiration is technically easier to perform than intercostal tube drainage. In this systematic review, we seek to compare the clinical efficacy and safety of simple aspiration versus intercostal tube drainage for management of primary spontaneous pneumothorax. This review was first published in 2007 and was updated in 2017. OBJECTIVES: To compare the clinical efficacy and safety of simple aspiration versus intercostal tube drainage for management of primary spontaneous pneumothorax. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 1) in the Cochrane Library; MEDLINE (1966 to January 2017); and Embase (1980 to January 2017). We searched the World Health Organization (WHO) International Clinical Trials Registry for ongoing trials (January 2017). We checked the reference lists of included trials and contacted trial authors. We imposed no language restrictions. SELECTION CRITERIA: We included randomized controlled trials (RCTs) of adults 18 years of age and older with primary spontaneous pneumothorax that compared simple aspiration versus intercostal tube drainage. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion, assessed trial quality, and extracted data. We combined studies using the random-effects model. MAIN RESULTS: Of 2332 publications obtained through the search strategy, seven studies met the inclusion criteria; one study was ongoing and six studies of 435 participants were eligible for inclusion in the updated review. Data show a significant difference in immediate success rates of procedures favouring tube drainage over simple aspiration for management of primary spontaneous pneumothorax (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.69 to 0.89; 435 participants, 6 studies; moderate-quality evidence). Duration of hospitalization however was significantly less for patients treated by simple aspiration (mean difference (MD) -1.66, 95% CI -2.28 to -1.04; 387 participants, 5 studies; moderate-quality evidence). A narrative synthesis of evidence revealed that simple aspiration led to fewer adverse events (245 participants, 3 studies; low-quality evidence), but data suggest no differences between groups in terms of one-year success rate (RR 1.07, 95% CI 0.96 to 1.18; 318 participants, 4 studies; moderate-quality evidence), hospitalization rate (RR 0.60, 95% CI 0.25 to 1.47; 245 participants, 3 studies; very low-quality evidence), and patient satisfaction (median between-group difference of 0.5 on a scale from 1 to 10; 48 participants, 1 study; low-quality evidence). No studies provided data on cost-effectiveness. AUTHORS' CONCLUSIONS: Available trials showed low to moderate-quality evidence that intercostal tube drainage produced higher rates of immediate success, while simple aspiration resulted in a shorter duration of hospitalization. Although adverse events were reported more commonly for patients treated with tube drainage, the low quality of the evidence warrants caution in interpreting these findings. Similarly, although this review observed no differences between groups when early failure rate, one-year success rate, or hospital admission rate was evaluated, this too needs to be put into the perspective of the quality of evidence, specifically, for evidence of very low and low quality for hospitalization rate and patient satisfaction, respectively. Future adequately powered research is needed to strengthen the evidence presented in this review.


Subject(s)
Chest Tubes , Pneumothorax/therapy , Suction , Drainage , Humans , Length of Stay , Patient Satisfaction , Randomized Controlled Trials as Topic
9.
Int J Primatol ; 38(4): 732-750, 2017.
Article in English | MEDLINE | ID: mdl-28845070

ABSTRACT

Primate vocalizations convey a variety of information to conspecifics. The acoustic traits of these vocalizations are an effective vocal fingerprint to discriminate between sibling species for taxonomic diagnosis. However, the vocal behavior of nocturnal primates has been poorly studied and there are few studies of their vocal repertoires. We compiled a vocal repertoire for the Endangered Sambirano mouse lemur, Microcebus sambiranensis, an unstudied nocturnal primate of northwestern Madagascar, and compared the acoustic properties of one of their call types to those of M. murinus and M. rufus. We recorded vocalizations from radio-collared individuals using handheld recorders over 3 months. We also conducted an acoustic survey to measure the vocal activity of M. sambiranensis in four forest habitat types at the study site. We identified and classified five vocalization types in M. sambiranensis. The vocal repertoires of the three Microcebus species contain very similar call types but have different acoustic properties, with one loud call type, the whistle, having significantly different acoustic properties between species. Our acoustic survey detected more calls of M. sambiranensis in secondary forest, riparian forest, and forest edge habitats, suggesting that individuals may prefer these habitat types over primary forest. Our results suggest interspecific differences in the vocal repertoire of mouse lemurs, and that these differences can be used to investigate habitat preference via acoustic surveys.

10.
Am J Primatol ; 75(12): 1196-208, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23897561

ABSTRACT

The ability to increase energy storage when food is abundant for later use during late gestation and early lactation is often considered the primary benefit of the capital breeding strategy (clustering conceptions during high food periods, HFP) that promotes reproductive success among females living in unpredictable environments. Capital breeding, however, may also enable preconceptive females to increase hormone production for ovulation, which has been linked to energetic condition in capital breeders, and/or allow females entering the subsequent HFP to increase their energetic condition in order to continue nursing unweaned infants. Here, we investigate whether capital breeding provides these additional benefits in 16 female Sanje mangabeys (Cercocebus sanjei) and determine the dietary strategies used to increase energetic condition (measured by urinary C-peptide: UCP) during the HFP. Fecal estradiol (fE2 ) and UCP were negatively correlated with number of cycles before conception (r = -0.591, r = -0.646, P < 0.01) and were highest in conceptive cycles. Both peri-conceptive (preconception and early gestation) and non-peri-conceptive (lactation) females increased energetic condition over the HFP (r = 0.612, r = 0.583, P < 0.001) by increasing dietary fat (r = 0.619, r = 0.703, P < 0.001) and, for non-peri-conceptive females, protein (r = 0.437, P < 0.001). Feeding intake rate (FIR) and time spent foraging and feeding did not change over the HFP; however, non-peri-conceptive females exhibited a faster FIR compared to peri-conceptive females (t = -2.324, P < 0.05), consuming almost twice as much food per unit time. The results of this study confirm that Sanje mangabeys benefit in multiple phases of the reproductive cycle by using capital breeding, which may explain how this strategy promotes female reproductive success.


Subject(s)
Cercocebus/physiology , Feeding Behavior , Fruit , Reproduction/physiology , Animals , Body Composition , Diet , Energy Metabolism , Female , Sexual Behavior, Animal
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