scholarly journals The Orang-Utan in North Borneo

Oryx ◽  
1961 ◽  
Vol 6 (1) ◽  
pp. 39-42 ◽  
Author(s):  
Ken Stott ◽  
C. Jackson Selsor

In October, 1959, Karl W. Kenyon, Research Biologist of the U.S. Fish and Wildlife Service, and the writers, spent three weeks in North Borneo observing wild primates. During this brief period, we questioned both European and native residents of the Colony on the relative abundance of orang-utans (Pongo pygmaeus) in various sectors, and we carefully recorded such indications as we ourselves noted. Although our own encounters with wild orang-utans were limited, we saw numerous nests, many of recent construction. The results of our inquiries and observations were encouraging enough for us to conclude that the orang in North Borneo is, for the present, in no danger of extinction and that it survives in moderate numbers wherever suitable habitat exists. This in itself should offer sufficient inducement to afford every possible sort of protection to the North Bornean survivors of a species that, elsewhere within its comparatively limited range, is becoming scarce or has already disappeared altogether.

Author(s):  
Mark Boyce ◽  
Jean-Michel Gaillard

The gray wolf (Canis lupus) was extirpated from Yellowstone National Park by U.S. Government personnel during 1914-1926. Since then, occasional reports of wolves in Yellowstone National Park have been recorded (Weaver 1978), but no recent records exist of wolves breeding in the park. In recent years, public attitudes towards predators have changed such that predators are more commonly viewed as an integral component of natural ecosystems (see e.g., Mech 1970, Despain et al. 1986, Dunlap 1988). An increasing proportion of the American public desires that wolves be reestablished in Yellowstone National Park (McNaught 1987, Bath 1991). ln 1987, the U.S. Fish and Wildlife Service approved a Recovery Plan for the Northern Rocky Mountain wolf (U.S. Fish & Wildlife Service 1987). Before proceeding with wolf recovery, however, Congress appropriated funds in 1988 and 1989 and directed that studies be conducted by the U.S. Fish and Wildlife Service and the National Park Service to determine the effects of wolf recovery on ungulate populations. Boyce (1990) developed a predator-prey model for ungulate populations in Yellowstone National Park as a part of this Congressional charge to determine the probable outcome of wolf recovery. Our purpose is to expand upon the simulation model of Boyce (1990) to predict the probable consequences of wolf reintroduction in Yellowstone National Park to ungulate populations in Jackson Hole and along the North Fork of the Shoshone River. As in the previous model, this model allows the user to choose among several likely management scenarios. By manipulating alternatives, the user of the model can explore the consequences of management actions. In particular, it is essential to be able to anticipate if wolves will be culled if they leave the parks, if poaching can be controlled within the park, and if hunting for bison and elk will continue in the Yellowstone River valley north of Gardiner, Montana. Any such model must incorporate the natural variability in the environment, because the vagaries of climate can have enormous effects on ecological processes. Therefore, the model is a stochastic one, i.e., it contains random variation in climatic variables. Such stochastic model structure is important because it helps to educate the user that it is impossible to predict precisely the consequences of wolf recovery. It is not the purpose of this effort to offer recommendations for whether wolf recovery should take place, but rather to provide resource managers with an additional tool which will assist them in making that decision.


2019 ◽  
Vol 3 (3) ◽  
Author(s):  
Asa McKercher

Too Close for Comfort: Canada, the U.S. Civil Rights Movement, and the North American Colo(u)r Line


Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1135
Author(s):  
Carolyn Payus ◽  
Lim Ann Huey ◽  
Farrah Adnan ◽  
Andi Besse Rimba ◽  
Geetha Mohan ◽  
...  

For countries in Southeast Asia that mainly rely on surface water as their water resource, changes in weather patterns and hydrological systems due to climate change will cause severely decreased water resource availability. Warm weather triggers more water use and exacerbates the extraction of water resources, which will change the operation patterns of water usage and increase demand, resulting in water scarcity. The occurrence of prolonged drought upsets the balance between water supply and demand, significantly increasing the vulnerability of regions to damaging impacts. The objectives of this study are to identify trends and determine the impacts of extreme drought events on water levels for the major important water dams in the northern part of Borneo, and to assess the risk of water insecurity for the dams. In this context, remote sensing images are used to determine the degree of risk of water insecurity in the regions. Statistical methods are used in the analysis of daily water levels and rainfall data. The findings show that water levels in dams on the North and Northeast Coasts of Borneo are greatly affected by the extreme drought climate caused by the Northeast Monsoon, with mild to the high risk recorded in terms of water insecurity, with only two of the water dams being water-secure. This study shows how climate change has affected water availability throughout the regions.


2009 ◽  
Vol 19 (1) ◽  
pp. 63-76 ◽  
Author(s):  
BORIS A. TINOCO ◽  
PEDRO X. ASTUDILLO ◽  
STEVEN C. LATTA ◽  
CATHERINE H. GRAHAM

SummaryThe Violet-throated MetaltailMetallura baroniis a high altitude hummingbird endemic to south-central Ecuador currently considered globally ‘Endangered’. Here we present the first detailed assessment of its distribution, ecology and conservation. We first used a maximum entropy model (Maxent model) to create a predicted distribution for this species based on very limited species occurrence data. We used this model to guide field surveys for the species between April and October 2006. We found a positive relationship between model values and species presence, indicating that the model was a useful tool to predict species occurrence and guide exploration. In the sites where the metaltail was found we gathered data on its habitat requirements, food resources and behaviour. Our results indicate that Violet-throated Metaltail is restricted to the Western Cordillera of the Andes Mountains in Azuay and Cañar provinces of Ecuador, with an area of extent of less than 2,000 km2. Deep river canyons to the north and south, lack of suitable habitat, and potential interspecific competition in the east may limit the bird's distribution. The species occurred in three distinct habitats, includingPolylepiswoodland, the upper edge of the montane forest, and in shrubby paramo, but we found no difference in relative abundance among these habitats. The metaltail seems to tolerate moderate human intervention in its habitats as long as some native brushy cover is maintained. We found thatBrachyotumsp.,Berberissp., andBarnadesiasp. were important nectar resources. The ‘Endangered’ status of this species is supported due to its restricted distribution in fragmented habitats which are under increasing human pressures.


2015 ◽  
Vol 28 (14) ◽  
pp. 5813-5829 ◽  
Author(s):  
Joseph A. Santanello ◽  
Joshua Roundy ◽  
Paul A. Dirmeyer

Abstract The coupling of the land with the planetary boundary layer (PBL) on diurnal time scales is critical to regulating the strength of the connection between soil moisture and precipitation. To improve understanding of land–atmosphere (L–A) interactions, recent studies have focused on the development of diagnostics to quantify the strength and accuracy of the land–PBL coupling at the process level. In this paper, the authors apply a suite of local land–atmosphere coupling (LoCo) metrics to modern reanalysis (RA) products and observations during a 17-yr period over the U.S. southern Great Plains. Specifically, a range of diagnostics exploring the links between soil moisture, evaporation, PBL height, temperature, humidity, and precipitation is applied to the summertime monthly mean diurnal cycles of the North American Regional Reanalysis (NARR), Modern-Era Retrospective Analysis for Research and Applications (MERRA), and Climate Forecast System Reanalysis (CFSR). Results show that CFSR is the driest and MERRA the wettest of the three RAs in terms of overall surface–PBL coupling. When compared against observations, CFSR has a significant dry bias that impacts all components of the land–PBL system. CFSR and NARR are more similar in terms of PBL dynamics and response to dry and wet extremes, while MERRA is more constrained in terms of evaporation and PBL variability. Each RA has a unique land–PBL coupling that has implications for downstream impacts on the diurnal cycle of PBL evolution, clouds, convection, and precipitation as well as representation of extremes and drought. As a result, caution should be used when treating RAs as truth in terms of their water and energy cycle processes.


2021 ◽  
Author(s):  
Matthew Howse

<p><b>Social wasps are considered among the most successful and impactful invasive species in the world. One species, Polistes dominula has spread from its native Mediterranean range to every continent except Antarctica. This wasp reached New Zealand in the last decade where it has established in the north of the South Island, however, reports of its presence are increasing throughout the country. Due to its recent arrival in New Zealand, little is known about where this species is likely to establish or what impacts it may have on local insect communities. In this thesis, I conducted two studies to investigate these questions, providing valuable information that may inform future management of this invasive species. </b></p><p>In chapter 2, I used two bioclimatic modelling methods to predict areas of suitable habitat across four regions in the southern hemisphere. These models were informed by global temperature and precipitation data as well as global distribution occurrence data of P. dominula. These data were used to estimate conditions most highly correlated with the presence of this wasp. The models identified large areas across the target regions that were climatically suitable for the establishment of P. dominula. Many of these areas are not known to currently contain populations of this species, representing habitat potentially vulnerable to further invasion by P. dominula. Areas across South America, South Africa and Australia were predicted to be climatically suitable. In New Zealand, much of the North Island and eastern parts of the South Island were predicted to be suitable habitat for this wasp. These results suggest that P. dominula could potentially establish across more of the country and expand its invaded range. Information provided by these models may guide conservation and biosecurity management by highlighting key areas where prevention and mitigation should be prioritized. </p><p>In chapter 3, I used molecular diet analysis to investigate the range of prey being utilised by P. dominula in New Zealand. Using DNA barcoding, larval gut contents of P. dominula and another closely related species, Polistes chinensis, were analysed to identify what species were present in the diet of both wasps. Butterflies and moths (Lepidoptera) were found to be the most highly represented order in both species’ diets. True bugs (Hemiptera) and flies (Diptera) were also abundant. Both wasps were shown to consume a range of native and introduced species including a number of agricultural pests. P. dominula was found to utilise a wider range of prey than P. chinensis. This more diverse prey range, combined with known differences in nesting behaviour, suggest that P. dominula may represent a more significant threat to invertebrate diversity than the already well-established P. chinensis. These results may inform conservation and biosecurity managers on which species are most at risk where this new invasive wasp becomes established. </p><p>This thesis provides insights into the potential impacts of a new invasive species to New Zealand. Both chapters represent the first time that these methods have been used to study P. dominula. This work highlights the need for continued monitoring of wasp populations throughout New Zealand, especially in regions highlighted as vulnerable to P. dominula establishment. We also suggest the need to prioritise the conservation of ‘at-risk’ species in coastal and human-altered habitats. Increased public engagement through the citizen-science initiatives should be encouraged while more research into management and control methods is recommended.</p>


Author(s):  
Alyssa M. Neir ◽  
Michael E. Campana

To deal with boundary and transboundary water issues along their border, the United States and Mexico established the International Boundary and Water Commission (IBWC) in 1889. Initially dealing only with surface water flows, its flexibility permitted changes such that groundwater and water quality issues could be addressed. In 1994, the U.S., Mexico, and Canada adopted the North American Free Trade Agreement (NAFTA) primarily to facilitate trade, but which can govern water as an article of commerce. Both NAFTA and the IBWC have been instrumental in promoting peaceful solutions to water issues. The article examines three cases: (1) Mexico's protesting of a U.S. plan to line the All-American Canal on the Mexico-California; (2) the underdelivery of Mexican Rio Grande water to the U.S. state of Texas; and (3) the case of an aquifer entirely within Mexico whose supply is being stressed because of a shift in agricultural production prompted by NAFTA. The article concludes that both countries should: (1) develop a more formal system for groundwater issues and (2) exercise vigilance with respect to NAFTA's ability to treat water solely as an economic good.


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