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How Can We Predict and Determine the Ecological Carrying Capacity of a Predator Species in an Enclosed Wildlife Protected Area?

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How Can We Predict and Determine the Ecological Carrying Capacity of a Predator Species in an Enclosed Wildlife Protected Area? Forestry Research and Engineering: International Journal Review Article Open Access How can we predict and determine the ecological carrying capacity of a predator species in an enclosed wildlife protected area? Abstract Volume 4 Issue 1 - 2020 Knowledge and insights on the ecological carrying capacity of a predator species is crucial for the conservation and management of an enclosed wildlife protected area. The objective Solomon Ayele Tadesse of this review was to suggest and discuss the relevant factors and formulate quantitative College of Agriculture and Natural Resource Sciences, Ethiopia statistical model that helps accurately predict and determine the ecological carrying capacity of a predator species in an enclosed system. To accurately predict and determine Correspondence: Solomon Ayele Tadesse, Department of Natural Resources Management, College of Agriculture and the ecological carrying capacity of a predator species, theoretical and empirical quantitative Natural Resource Sciences, Debre Berhan University, Ethiopia, models should consider as many relevant factors as possible by which reliable and valid Tel +251-111-6815440/+251-946-703660, Fax +251-111- estimations can be made. Having considered several imperative factors, this review 6812065, Email suggested and formulated a quantitative statistical model that helps accurately predict and determine the ecological carrying capacity of a predator species in an enclosed system. It is Received: November 13, 2019 | Published: January 02, 2020 recommended that wildlife conservation researchers should consider the various essential factors in an integrated fashion while testing their hypotheses through experimental and/or observational scientific studies. More importantly, the application of multiple hypotheses testing will help improve the accuracy in making reliable and valid estimations on the ecological carrying capacity of a predator species in a complex natural system. Keywords: complex natural system, conservation and management, predators, prediction, theoretical and empirical quantitative models Introduction an enclosed wildlife protected area.8 An enclosed wildlife protected area is to mean that the wildlife reserve is self-sustaining and there Prey-predator interaction is among the major evolutionarily is no influx of wild animals to come from outside or losses to the and ecological forces which play imperative role to determine the outside. There are various theoretical and empirical quantitative distribution, abundance, habitat selection, behaviour, fitness, and models that help predict and determine the ecological carrying 1–5 population dynamics of different species in a biotic community. capacity of a predator species in an enclosed system.8–18 However, a Such kinds of interaction are crucial to understanding the ecological central challenge in wildlife ecology is to develop quantitative model and evolutionarily relationships, pathways, and co-evolution between that faithfully captures all important mechanistic details of natural prey and predator species in an ecological system. Moreover, it can systems that are required in making reliable and valid predictions on increase our insights to discern the attributes of ecosystems, including the ecological carrying capacity of a predator species in an enclosed structure, function, interactions-interdependence, heterogeneity, system. This is because the ecosystem where predator and prey complexity, spatial, and temporal dynamics. It is also relevant to species interact and co-exist is naturally very complex. develop an insight on how natural selection shapes the morphology, behaviour, anatomy, and physiology of prey versus predator species. Hence, predicting and determining the ecological carrying capacity On top of these, such kinds of knowledge are important to understand of a predator species in an enclosed system needs careful and objective how energy flows and matter cycles through the various trophic insights and judgments in making reliable and valid estimations.8,17 levels in an ecosystem.6,7 All these insights and knowledge in turn To accurately predict and determine the ecological carrying capacity help conserve and manage wildlife, including saving the endangered of a predator species, quantitative models should consider as many species from extinction, and also to sustainably utilize the biodiversity relevant factors as possible by which reliable and valid estimations can found in an area. be made. The objective of this review was to suggest and discuss the relevant factors and formulate quantitative statistical model that helps Ecological carrying capacity can be arbitrarily defined as the accurately predict and determine the ecological carrying capacity of optimum number of individuals (i.e. all sex-age classes) of a species a predator species in an enclosed wildlife reserve. Therefore, the goal that an environment can support over time through the provision of this paper is to highlight existing concerns about the ecological of essential habitat requirements, including space, energy, water, carrying capacity of a predator species in an enclosed system, nutrients, oxygen, food, cover, nesting site, and the like. Therefore, which may assist wildlife decision- and policy-makers, researchers, knowledge and insights on the ecological carrying capacity of a managers, and conservationists to optimally conserve and manage predator species is crucial for the conservation and management of predator species in an enclosed wildlife reserve. Submit Manuscript | http://medcraveonline.com Forest Res Eng Int J. 2020;4(1):1‒8. 1 ©2020 Tadesse. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Copyright: How can we predict and determine the ecological carrying capacity of a predator species in an enclosed 2 wildlife protected area? ©2020 Tadesse Testable hypotheses The prey behaviour A summary of the relevant factors that help formulate the plausible Predators directly affect their prey by killing and consuming them. hypotheses, their expected effects, and intensities to accurately Nonetheless, this is not the only way they can affect them. Non-lethal predict and determine the ecological carrying capacity of a predator effects, such as fear and apprehension generated from the possibility species in an enclosed wildlife protected area was presented in Table of being attacked, may be enough to change prey behaviour.4,20–25 1. Factor refers to the process input that a researcher manipulates to This suggests that non-lethal effects can affect the fitness of prey cause a change in the output. Effect implies how changing the setting individuals because the prey’s options are constrained and the of a factor changes the response. Intensity refers to the measurable behavioural response may be costly,21,22 and even physiologically amount of the strength of a factor on the ecological carrying capacity stressful when it is at its extreme case.25 For example, previous studies of a predator species in an enclosed wildlife protected area. Each on invertebrates,26–28 and amphibians,29 have shown that non-lethal of the relevant factors, their expected effects, and intensities on the effects may be larger than lethal effects in determining the habitat ecological carrying capacity of a predator species in an enclosed section, patch use, foraging behaviour, morphology, survival and system were thoroughly discussed as followed. reproductive rates, activity density, time budgets and distribution of animals over a range of trophic levels.22,25 Due to the potentially high The abundance and availability of preferred prey costs of avoiding predation and the tendency for large portions of species populations to respond to risk of predation, the risk effects of predators Prey-predator interaction serves as a basis in predicting and can have impacts on individuals of prey species that may even surpass 30 determining the prey-specific biomass intake of a predator species those of direct predation. This is because effects of predation risk 31 which can in turn be used to estimate the ecological carrying capacity of a can exist even when direct rate of predation is zero. Risk-sensitive predator species in an enclosed wildlife reserve.8 The prey preferences behaviour resulting from non-lethal causes may ultimately affect the of predators affect prey-predator interaction. Understanding the foraging behaviour, habitat use, change ecological processes, and processes behind such kinds of phenomena is essential in predicting potentially affect the structure of the biodiversity and the function of and determining the dynamics of biotic assemblage.17,18 Hence, a an ecosystem. predator species that preys on a readily surveyed prey species can To reduce the negative impacts of predation risk, individuals have its ecological carrying capacity predicted and determined based of prey species may develop different behavioural strategies. For 8 on the abundance and availability of its preferred prey species. For example, prey develop anti-predator behaviour, such as spending example, previous studies predicted that the abundance of a predator more time being vigilant and less time feeding, using apprehension species is positively correlated with the abundance and availability or restricting their feeding to certain times, feeding in larger groups,32 8,9,16–18 of preferred prey species. Accordingly, I hypothesize
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