Economics of a nest-box program for the conservation of an endangered species: a reappraisal

2001 ◽  
Vol 31 (11) ◽  
pp. 1992-2003 ◽  
Author(s):  
Daniel A Spring ◽  
Michael Bevers ◽  
John OS Kennedy ◽  
Dan Harley

An optimization model is developed to identify timing and placement strategies for the installation of nest boxes and the harvesting of timber to meet joint timber–wildlife objectives. Optimal management regimes are determined on the basis of their impacts on the local abundance of a threatened species and net present value (NPV) and are identified for a range of NPV levels to identify production possibility frontiers for abundance and NPV. We apply the model to a case study focusing on an area of commercially productive mountain ash (Eucalyptus regnans F. Muell.) forest in the Central Highlands region of Victoria, Australia. The species to be conserved is Leadbeater's possum (Gymnobelideus leadbeateri McCoy), which is locally limited by a scarcity of nesting hollows. The modeling is exploratory but indicates that nest boxes may offer a promising population recovery tool if consideration is taken of their placement and areal extent through time.

2002 ◽  
Vol 32 (12) ◽  
pp. 2244-2247 ◽  
Author(s):  
D B Lindenmayer ◽  
C MacGregor ◽  
P Gibbons

Spring et al. (D.A. Spring, M. Bevers, J.O.S. Kennedy, and D. Harley. 2001. Can. J. For. Res. 31: 1992–2003) recently published a paper on the economics of a nest-box program for the endangered arboreal marsupial, Leadbeater's possum (Gymnobelideus leadbeateri) in southeastern Australian forests. While their paper is a useful one, there are some important limitations of nest-box programs that need to be highlighted. In the case of Leadbeater's possum, we have undertaken extensive nest-box studies in Victoria mountain ash (Eucalyptus regnans F. Muell.) forests, where the vast majority of populations of the species now occur. Although large numbers of nest boxes have been deployed, very few have actually been occupied, which is a major problem since the effectiveness of any nest-box program will depend on patterns of use by the target species. Given very low levels of nest-box occupancy, harvesting regimes such as those that lead to on-site tree retention are needed to better conserve hollow-dependent species like Leadbeater's possum. Moreover, the need for nest boxes in the first place indicates that logging practices are presently not ecologically sustainable, and modified forestry practices need to be adopted.


2021 ◽  
Author(s):  
Adekunle Tirimisiyu Adeniyi ◽  
Miracle Imwonsa Osatemple ◽  
Abdulwahab Giwa

Abstract There are a good numbers of brown hydrocarbon reservoirs, with a substantial amount of bypassed oil. These reservoirs are said to be brown, because a huge chunk of its recoverable oil have been produced. Since a significant number of prominent oil fields are matured and the number of new discoveries is declining, it is imperative to assess performances of waterflooding in such reservoirs; taking an undersaturated reservoir as a case study. It should be recalled that Waterflooding is widely accepted and used as a means of secondary oil recovery method, sometimes after depletion of primary energy sources. The effects of permeability distribution on flood performances is of concerns in this study. The presence of high permeability streaks could lead to an early water breakthrough at the producers, thus reducing the sweep efficiency in the field. A solution approach adopted in this study was reserve water injection. A reverse approach because, a producing well is converted to water injector while water injector well is converted to oil producing well. This optimization method was applied to a waterflood process carried out on a reservoir field developed by a two - spot recovery design in the Niger Delta area of Nigeria that is being used as a case study. Simulation runs were carried out with a commercial reservoir oil simulator. The result showed an increase in oil production with a significant reduction in water-cut. The Net Present Value, NPV, of the project was re-evaluated with present oil production. The results of the waterflood optimization revealed that an increase in the net present value of up to 20% and an increase in cumulative production of up to 27% from the base case was achieved. The cost of produced water treatment for re-injection and rated higher water pump had little impact on the overall project economy. Therefore, it can conclude that changes in well status in wells status in an heterogenous hydrocarbon reservoir will increase oil production.


2000 ◽  
Vol 30 (11) ◽  
pp. 1817-1823 ◽  
Author(s):  
Karin Öhman

Harvest activities tend often to create landscapes where the old forest is fragmented into isolated patches that provide marginal conditions for species that inhabit forest interiors. This paper presents a long-range planning model designed to maximize the net present value and to create continuous patches of old forest. In this model, the spatial structure of old forest is controlled by core area and edge habitats. Core area is defined as the area of old forest that is free of edge effects from surrounding habitats. The core area requirement is set to a fixed value for each of a number of time periods, whereas the area of edge habitats, which should be as small as possible, is weighted against the net present value. The model is applied in a case study to an actual landscape consisting of 755 stands of forest in northern Sweden and solved using simulated annealing. The results show that distinct continuous patches of old forest are created when both a core area requirement and consideration of the amount of edge habitats are included in the problem formulation. The cost of creating continuous areas of old forest was found to be significant.


2014 ◽  
Vol 54 (9) ◽  
pp. 1248 ◽  
Author(s):  
C. K. M. Ho ◽  
T. Jackson ◽  
M. T. Harrison ◽  
R. J. Eckard

Ewes with the fecundity Booroola (FecB) gene produce more lambs per ewe on average than ewes without the gene and offers a potential way to decrease greenhouse gas emissions (net and per unit animal product) without reducing lamb production if the lambs can be reared to market weights. Using a case study farm in south-west Victoria, a biophysical modelling study has previously showed that increased ewe fecundity from 1 to 1.5 lambs per ewe increased production by 27% and reduced net farm emissions by 21% for the same long-term stocking rate. In this study, a whole-farm economic analysis was used to investigate the relative merit of the same case study farm, with high-fecundity ewes, compared with a baseline system that represented a typical prime lamb enterprise in the region. An additional system comprising ewes with high fecundity at a lower stocking rate than the case study farm was also examined. The analysis was undertaken to establish which farm systems represented the most economically efficient use of all the resources that are employed over a run of years, and involved estimating the net present value of annual profits earned by the farm in each scenario, taking into account the total value of capital used. The potential revenue from the sale of carbon credits through the Carbon Farming Initiative was also investigated. After accounting for the additional costs involved, increasing ewe fecundity resulted in an increase in annual whole-farm profit compared with the baseline system, but risk, considered as the variability in farm profit, also increased. Decreasing stocking rate for the high-fecundity system reduced annual operating profit and net present value at a 5% discount rate, but had less risk compared with the higher stocking rate system. While both systems that incorporated high-fecundity ewes reduced greenhouse gas emissions, revenue from the sale of carbon credits was small compared with revenue from the sale of lambs, wool and culled ewes. Despite this, and assuming the required increases in fertility and weaning rates could be achieved consistently on-farm, ewes with high fecundity may offer producers the opportunity to increase production and profit as well as decrease greenhouse gas emissions.


2017 ◽  
Vol 35 (12) ◽  
pp. 1220-1225 ◽  
Author(s):  
Tao Zhang ◽  
Fang Liang ◽  
Wanhe Hu ◽  
Xiaomeng Yang ◽  
Hongzhong Xiang ◽  
...  

Significant quantities of bamboo waste are generated in Zhejiang province, China. Many small businesses in this area convert this waste to biochar for use as a cooking fuel (in residential barbecues). This case study was conducted to evaluate the potential economic benefits of building and operating an industrial-sized plant in this province, yielding 500 tonnes per year. The researchers developed a conceptual design for a hypothetical biochar plant and then calculated net present value (NPV), investment payback period (PBP), internal rate of return (IRR), and sensitivity analysis. Results show that the static investment PBP would be 2.58 years, the IRR would be 38.8%, and the NPV would be US$ 486,700. The IRR would be higher than the forestry industry benchmark (11%), indicating that a production line of bamboo-biochar with the stated yield not only could generate higher profits, but also could achieve a better return on investment. Thus, this study indicates that there are good market prospects for the bamboo-biochar industry in this region. The influence of sales prices on the IRR was more than that of operational costs, indicating that a large-scale plant should be designed to produce a high-quality bamboo-biochar. Supply chain issues such as transportation distances between locations where bamboo wastes are generated and the biochar plant should be considered in advance when siting new bamboo-biochar plants. The results from this research provide guidance to those considering development of bamboo-biochar plants in other parts of China.


Author(s):  
Sylwia Wciślik ◽  
Dagmara Kotrys-Działak

The paper addresses an analysis of the efficiency and profitability of the operation of a photovoltaic installation located in the geometric centre of Europe (near Białystok, Poland), where the intensity of solar irradiation is not too high compared to other European countries. It is calculated that in that place average solar irradiation being lower even by approx. 26 kWh than that for the whole Europe, which results in a 26% drop in the economic potential of the utilisation of solar energy for its conversion. A case study and an economic analysis show that without minimum funding amounting to 50% of the investment costs paid for the modernisation of a central heating system assisted by PV cells, the time of return of pecuniary expenditures exceeds 7 years. Apart from the Simple Pay-Back Time SPBT, discount indicators determined in the paper also include the net present value NPV and the internal rate of return IRR. Moreover, a direct ecological effect has been determined for such an investment.


Author(s):  
Rabiatul Adawiah Gasnawati ◽  
Abdi Abdi ◽  
Awaluddin Hamzah

The purpose of this study was to determine the sensitivity of ornamental plant business in Kendari City as a case study on dahlia ornamental plant business. This research was conducted in Kendari City which was determined purposively on the dahlia ornamental plant business. The research was conducted from July to November 2019. The analysis used in this study is an analysis of efficiency and income consisting of net present value (NPV) income benefit ratio (NBCR), internal rate of return (IRR), payback period (PBP). The results of the sensitivity analysis of ornamental plant businesses with increased production costs by 5% and selling prices decreased by 5%, the value of the NPV, NBCR, IRR and payback period shows a good value so that the ornamental plant business is feasible to be cultivated because it can return all investment costs used


Author(s):  
Andi Haris Muhammad ◽  
Daeng Paroka ◽  
Sabaruddin Rahman ◽  
` Syarifuddin

<p><em>The ability of a vessel to obtain catches is known as fishing vessel productivity. This greatly influences the feasibility level of the fishing operation. The objctive of the study is to evaluate the operational feasiblity level of 30 GT fishing vessel that operates in Sulawesi waters (case study INKA MINA 957). The use of  Net Present Value (NPV) and Internal Rate of Return (IRR) methods showed that the catch should be of more than minimum 116 ton per year or the NPV value at  Rp. 124.797.638,- with 10% interest rate assumption within 10 years. Furthermore, based on the internal rate of return (IRR) the interest obtained was approximately 12.2% which was higher than the market interest rate assumptions at about 2.2%</em><em>.</em> <em></em></p><p><strong><em>Keywords:</em></strong><strong><em> </em></strong><em>fishing vessel, operational feasibility, NPV and IRR</em></p><p align="center"><strong>ABSTRAK</strong></p><p class="Abstrakisi">Produktivitas kapal perikanan adalah kemampuan kapal untuk memperoleh hasil tangkapan ikan. Produktivitas ini sangat mempengaruhi tingkat kelayakan operasional. Penelitian ini bertujuan untuk mengukur tingkat kelayakan operasional kapal perikanan 30 GT yang beroperasi di perairan Sulawesi (studi kasus KM INKA MINA 957). Metode <em>Net Present Value (NPV)</em> dan <em>Internal Rate of Return (IRR)</em> telah digunakan untuk mengukur tingkat kelayakan operasional. Hasil analisis menunjukkan bahwa kapal perikanan layak dioperasikan dengan prediksi hasil tangkapan minimal sebesar 116 ton pertahun atau nilai <em>NPV</em> sebesar Rp.124.797.638,- dengan asumsi suku bunga 10% selama 10 tahun. Selanjutnya berdasarkan Metode <em>IRR</em> diperoleh suku bunga 12,2%, hasil ini lebih besar 2,2% sebagaimana asumsi suku bunga dipasaran.</p><p><em><strong>Kata kunci:</strong> kapal perikanan, kelayakan operasional, <em>NPV</em> dan <em>IRR</em><br /></em></p>


2003 ◽  
Vol 30 (3) ◽  
pp. 259 ◽  
Author(s):  
D. B. Lindenmayer ◽  
C. I. MacGregor ◽  
R. B. Cunningham ◽  
R. D. Incoll ◽  
M. Crane ◽  
...  

The results are reported of a nest-box study conducted in two locations in the mountain ash (Eucalyptus regnans) forests of the Central Highlands of Victoria (south-eastern Australia) to compare usage of different nest-box designs located at different heights in trees. A total of 96 nest boxes was established using a rigorous experimental design – two regions (Powelltown and Toolangi State Forests), two forest age classes (20-year post-logging regrowth and 60-year fire- and salvage-logging regrowth), two nest-box designs (large boxes with large entrance holes and small boxes with small entrance holes), and two heights at which nest boxes were attached to trees (3 m and 8 m above the ground). The study entailed setting out four nest boxes at each of 24 sites to meet the design criteria. Evidence of occupancy by vertebrates was recorded in a total of 19 of 96 boxes on 11 of 24 sites site during regular inspections over more than three years. Thirteen boxes were used by Leadbeater's possum (Gymnobelideus leadbeateri), six by the mountain brushtail possum (Trichosurus cunninghami) and seven by the common ringtail possum (Pseudocheirus peregrinus). The common ringtail possum and mountain brushtail possum were seen only in high–large boxes but Leadbeater's possum used all but the low–large boxes. There was evidence of spatial dependence in usage patterns, with all four boxes at a given site showing signs of eventually being occupied. Only two nest boxes located in mountain ash forest regenerating after the 1939 wildfires were occupied. Relatively limited use of nest boxes supports concerns about the use of a nest box over large scales and long timeframes as an effective recovery tool for species threatened by the loss and subsequent shortage in the numbers of naturally occurring hollows.


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