Reference no: EM133676438

Conservation Biology

Guidelines for the Population Viability Analysis (PVA) Assignment

Population viability assessments are important in conservation biology for two reasons. First, you may wish to determine whether a species or population requires management, such as translocations. Secondly, you may want to determine which conservation actions would have the biggest impact on population size, because, depending on population parameters [such as fecundity and mortality rates], some actions may have more impact than others. For example, for many long-lived, vertebrate species, it is much, much more impactful to prevent adult morality than to increase offspring survival. Sea turtles are an excellent example of this.

This assignment asks you to use the software VORTEX to evaluate the viability of a real endangered species facing extinction in Australia: Orange-bellied Parrots (Neophema chrysogaster). You are required to follow the guidelines in this document. In future, you may use this software to conduct similar analysis on other species as part of your employment.

Assignment Outline

Given their Critically Endangered IUCN conservation status, we are going to evaluate the viability of the Orange-bellied Parrot population, where "viability" is defined as Probability of Extinction (PE) over the next 100 years. We use PVA to determine management priorities for this species. Specially, the following topics should be discussed:
Estimate extinction risk for the current population (assuming N = 150) given its current life history parameters (reproductive rates, mortality rates, with their associated estimates of stochastic variability).

Define the relationship between initial population size (N) and population viability by repeating for a range of values for N (above and below). The set of values of N is up to you to decide - as long as you think the relationship is sufficiently defined and there are enough points for a graph.
Example question(s) to consider in your discussion:
What is the ideal initial population size to keep the population viable?
Would a captive breeding strategy be useful to increase population viability?

Evaluate the sensitivity of population viability estimates to changes in the mortality rates of juvenile and adult birds. You will need to change the mortality rates relative to the original values, e.g. increase/decrease juvenile mortality rate by 5%, 10%, 20% and 30% of the original value.
Example question(s) to consider in your discussion:
Would increasing/decreasing mortality rates have a significant impact on the population viability? If so, which life stage is more critical?
What are the conservation implications for such impact? How can we manage them?

Evaluate the sensitivity of population viability estimates to changes in the reproductive rates of female adult birds. Similarly, you will need to change the "percentage of female breeding" values relative to the original values.

Example question(s) to consider in your discussion:
Would increasing/decreasing reproductive rates of the female birds have a significant impact on the population viability?
What are the conservation implications for such impact? How can we manage them?

Evaluate the potential impact of inbreeding depression on the population viability. In order to do this, you will need to re-run steps 1 - 4 by selecting inbreeding depression in the parameters. Example question(s) to consider in your discussion:
What are the consequences of inbreeding?
Is there any way to minimise inbreeding depression?

Format of Assignmentand Submission Procedure
Write your report in the form of a scientific paper with a word limit between 2,000 - 3,000 words. This means the report cannot be a summary of Q&As. It has to be written in a coherent manner and presentable to a scientific journal, no point-form lists. You must include and refer to a reasonable number of relevant references. 5 is too few, 45 is too many.
Print format: 1.5 line spacing; Times New Roman or other legible font; 12 pt font size; include your name and student number on the top right corner of the first page.
The report should contain the following sections:
Title: should be concise and descriptive.

Abstract: should be a concise summary of each section (aims, methods, results and discussion) in your main paper. You need to keep your abstract fewer than 250 words.

Introduction: briefly outline the background of the work including a species profile and the use of PVA. More importantly, you need to state the aims/hypothesis of this work.

Methods: explain what you did, including the input data as a table and what parameters you have changed and how. Other people should be able to repeat what you did after reading your methods, so, please keep it concise but accurate.

Results: present the results using graphs or tables (the same data should be presented only in one format) and provide a commentary on the main trends in the data. Do not discuss your results in this section, but summarise them in writing. Do not put the same results in figures and tables. Do not include only figures and tables with no writing.

Discussion: interpret the results of your simulations. This is where you should address the questions in the Assignment Outline, although it does not have to be as questions and answers. Also in this section, you need to briefly address the possible shortcomings or flaws in the analysis. For example, are the assumptions that were made by the software valid? After completing the practical, do you think PVA has any value?

References: keep your reference style consistent (including in-text references - Harvard-style APA) and do not use websites or popular articles. Primary sources include journal articles, book chapters, refereed books, conference proceedings and government reports, etc.ASSESSMENT ITEM: PRACTICALS

TASK

Conducting population viability analyses is an important way to understand the influence of variability in different life stages on population outcomes. It is actually used by conservation biologists to make these determinations, and will be a saleable skill for you in the future.
You will conduct a population viability analysis for rare orange-bellied parrots, to determine if the population is viable, and what changes to demographic processes would influence viability. Your assignment is completely available on-line.

Introduction & definition of topics; statement of research questions

Description of what you did including changes of parameters & input data

Description of results; identifying trends, including graphs and/or tables; no discussion in results

Interpretation of results, implications for species management & further research; comments or the methods (advantages & disadvantages)
In-text citations are listed in reference section; consistent style

Quality of writing (sentence structure, paragraphs, grammar, etc); originality (ideas, approaches etc.)