Status and conservation of the only population of the Vulnerable owl-faced monkey Cercopithecus hamlyni in Rwanda

AbstractThe elusive, Vulnerable owl-faced monkey Cercopithecus hamlyni is a rare and little studied species and one of the least known of the African Cercopithecidae. This study describes the distribution and relative abundance of the only known population in East Africa, in Nyungwe National Park, Rwanda. This species is restricted to a small (32 km2) area of bamboo and bamboo–forest mix in the southern sector of the Park, close to the international border with Burundi. We present the first empirical data of its abundance in the bamboo forests of Nyungwe. A total length of 185 km of transect were surveyed to estimate relative abundance of diurnal primates. Encounter rates with the owl-faced monkey were 0.081 groups km-1 (n = 15). Mean group size was 3.6 individuals. Eight independent photographs of C. hamlyni were obtained from five camera traps during 182 camera-days. Four other species of primates occur in the bamboo forest: eastern chimpanzee Pan troglodytes schweinfurthii, Angola colobus Colobus angolensis, L’Hoest’s monkey Cercopithecus l’hoesti and blue monkey Cercopithecus mitis. The main threats to the bamboo forest are from the illegal harvesting of bamboo, trapping and tree-cutting. These threats originate from both Rwanda and Burundi. There is an urgent need for conservation action to halt the destruction and degradation of the bamboo forest and to ensure the long-term survival of the owl-faced monkey in Rwanda.

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Leopard Density Estimation within an Enclosed Reserve, Namibia Using Spatially Explicit Capture-Recapture Models

Animals ◽

10.3390/ani9100724 ◽

2019 ◽

Vol 9 (10) ◽

pp. 724

Author(s):

Noack ◽

Heyns ◽

Rodenwoldt ◽

Edwards

Keyword(s):

Management Strategies ◽

Camera Traps ◽

Spatially Explicit ◽

Conservation Areas ◽

Term Survival ◽

New Class ◽

Capture Recapture ◽

Wildlife Populations ◽

Effective Conservation

The establishment of enclosed conservation areas are claimed to be the driving force for the long-term survival of wildlife populations. Whilst fencing provides an important tool in conservation, it simultaneously represents a controversial matter as it stops natural migration processes, which could ultimately lead to inbreeding, a decline in genetic diversity and local extinction if not managed correctly. Thus, wildlife residing in enclosed reserves requires effective conservation and management strategies, which are strongly reliant on robust population estimates. Here, we used camera traps combined with the relatively new class of spatially explicit capture-recaptured models (SECR) to produce the first reliable leopard population estimate for an enclosed reserve in Namibia. Leopard density was estimated at 14.51 leopards/100 km2, the highest recorded density in Namibia to date. A combination of high prey abundance, the absence of human persecution and a lack of top-down control are believed to be the main drivers of the recorded high leopard population. Our results add to the growing body of literature which suggests enclosed reserves have the potential to harbour high densities and highlight the importance of such reserves for the survival of threatened species in the future.

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Introduction

The Ecology, Exploitation and Conservation of River Turtles ◽

10.1093/oso/9780195102291.003.0004 ◽

2004 ◽

Author(s):

Don Moll ◽

Edward O. Moll

Keyword(s):

Homo Sapiens ◽

Current Crisis ◽

Conservation Action ◽

Term Survival ◽

Pet Trade ◽

Turtle Species ◽

Modern Species ◽

Precipitous Decline ◽

Sustainable Population

The turtle species that dwell in the world’s rivers, play important, but incompletely understood and largely unappreciated, roles in both the ecology of their respective ecosystems, and in the economy and sociology of the human cultures through which their rivers flow. Accordingly, the precipitous decline of many populations from former levels, and the complete extirpation of some species from large areas of their former ranges is cause for alarm by those concerned, not only with turtles, but with the health and welfare of rivers and humans as well. The causes of these declines are virtually all the result of human activities—including those which involve direct predation on the turtles themselves (and their eggs), removal for the pet trade, and those which result in unfavorable changes in their habitats. The fact that no known modern species has yet been driven to total extinction is testimony to the resiliency and fecundity of river turtle species. This is no cause for complacency—many are almost certainly teetering on the brink now and are facing ever-increasing odds against long-term survival. Some species could be even now beyond hope of recovery, their populations sustained for a time by a relatively few long-lived adults without sufficient collective reproductive “power” to thwart the normal and various mortality sources which plague all turtles, and which their sheer numbers had formerly been able to overcome. However, we are still so ignorant of the population dynamics of these species that we know not which, if any, are doomed. It seems preferable, therefore, as we strive to conserve river turtle stocks that we assume the working philosophy that none is in this category, and focus our efforts and resources toward research and conservation action most likely to return even the most endangered species to robust, sustainable population levels. The roots of the current crisis predate history, beginning with our hominid ancestors, and particularly hunter-gather Homo sapiens’ unparalleled capacity to learn and adapt in order to maximize the harvest of all available food resources.

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Ongoing decline of suitable habitat for the Critically Endangered Gurney's pitta Hydrornis gurneyi

Oryx ◽

10.1017/s0030605320001258 ◽

2021 ◽

pp. 1-7

Author(s):

Tommaso Savini ◽

Nay Myo Shwe ◽

Niti Sukumal

Keyword(s):

Industrial Development ◽

Large Scale ◽

Legal Protection ◽

Critically Endangered ◽

Suitable Habitat ◽

Conservation Action ◽

Term Survival ◽

Long Term Survival ◽

Lowland Forests

Abstract From 1999 onwards, level, lowland forests (altitude < 150 m, slopes < 10°) in the Tanintharyi Region of southern Myanmar have been cleared on a large scale and replaced by oil palm plantations. This has resulted in a drastic decline in suitable habitat for several species, including Gurney's pitta Hydrornis gurneyi (Passeriformes, Pittidae). The habitat for this species has decreased by > 80%, leading to its categorization as Critically Endangered on the IUCN Red List in 2019. As threats in the region have continued, we updated information on the status of the species’ habitat in January 2020, and examined forest loss in the three strongholds where the species still persists in the wild. Since the previous estimate in 2017, suitable habitat in these locations has decreased by 8% (from 656 to 603 km2), with > 10% of the remaining area now in fragments of < 1 km2, which are unsuitable for the mid- to long-term survival of the species. Forest degradation and edge effects from increased fragmentation have led to further loss of suitable habitat in these strongholds. Projections indicate that unless conservation action is taken, all suitable habitat will disappear by 2080. The main threat to the long-term survival of Gurney's pitta is the lack of legal protection of primary lowland forests, resulting in uncontrolled clearance for small- and large-scale agriculture and industrial development. We provide recommendations to reduce the rate of loss of the remaining suitable habitat for the species.

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Using occupancy-based camera-trap surveys to assess the Critically Endangered primate Macaca nigra across its range in North Sulawesi, Indonesia

Oryx ◽

10.1017/s0030605319000851 ◽

2020 ◽

Vol 54 (6) ◽

pp. 784-793

Author(s):

Caspian L. Johnson ◽

Harry Hilser ◽

Matthew Linkie ◽

Rivo Rahasia ◽

Francesco Rovero ◽

...

Keyword(s):

Protected Areas ◽

Fragment Size ◽

Camera Trap ◽

Camera Traps ◽

Critically Endangered ◽

Anthropogenic Factors ◽

Forest Fragment ◽

Conservation Action ◽

Term Survival ◽

Macaca Nigra

AbstractPrimates are one of the most threatened groups of mammals. Understanding their patterns of population occurrence and abundance, especially in response to threats, is critical for informing conservation action. The crested black macaque Macaca nigra is the only Critically Endangered species of Sulawesi's seven endemic macaques. Little is known about its distribution or its response to deforestation and hunting. We conducted a camera-trap survey across the entire species range using an occupancy-based analytical approach to (1) establish the first range-wide baseline of occurrence, (2) investigate how environmental and anthropogenic factors influence occurrence, (3) identify priority conservation subpopulations, and (4) test the efficacy of the sampling and analytical protocol for temporal monitoring of M. nigra using occupancy as the state variable. From 9,753 camera-trap days, M. nigra was detected on 473 days at 77 of the 111 camera locations. Species occupancy was 0.66 and highest inside protected areas and closed canopy forest. We identified eight distinct subpopulations, based on distribution and forest fragment size. To inform future monitoring, we used a power analysis to determine if our effort would allow us to detect inter-annual occupancy declines of 10%, and found that 90 camera locations surveyed for 3 months (8,100 camera days) across three consecutive seasons is the effort required to detect such change with 80% certainty. Our study underscores the importance of well-managed protected areas and intact forests for the long-term survival of the crested black macaque, and tests the effectiveness of camera traps to monitor primates at the landscape scale.

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Caspases and apoptosis

Essays in Biochemistry ◽

10.1042/bse0380009 ◽

2002 ◽

Vol 38 ◽

pp. 9-19 ◽

Cited By ~ 121

Author(s):

Guy S Salvesen

Keyword(s):

Cysteine Proteases ◽

Signalling Pathways ◽

Term Survival ◽

Mature Adult ◽

Intracellular Signalling Pathways ◽

Adult Cell ◽

Caspase Family ◽

Cell Fragments ◽

Pro Inflammatory Cytokines

The ability of metazoan cells to undergo programmed cell death is vital to both the precise development and long-term survival of the mature adult. Cell deaths that result from engagement of this programme end in apoptosis, the ordered dismantling of the cell that results in its 'silent' demise, in which packaged cell fragments are removed by phagocytosis. This co-ordinated demise is mediated by members of a family of cysteine proteases known as caspases, whose activation follows characteristic apoptotic stimuli, and whose substrates include many proteins, the limited cleavage of which causes the characteristic morphology of apoptosis. In vertebrates, a subset of caspases has evolved to participate in the activation of pro-inflammatory cytokines, and thus members of the caspase family participate in one of two very distinct intracellular signalling pathways.

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