1. Community Ecology BCB331 Mark J Gibbons, Room Z108, BCB Department, UWC Tel: 021 959 2475. Email: mgibbons@uwc.ac.za Image acknowledgements – http://www.google.com

2. Some Definitions Environmental Condition Physical environmental variable or factor, that varies in space and time, and to which organisms respond Examples include: Temperature, salinity, moisture, elevation, depth, nitrogen concentration of water, beach grain size etc etc etc Environmental Gradient e.g. Temperature Performance or Abundance Species A Species B Species C Species D Species E Species F Species G Species H Species I Species J

3. Resource Something that is required or used by an organism, the quantities of which can be reduced by the organism Examples include: Dissolved oxygen, sunlight, water, carbon dioxide, mineral nutrients, organisms as food

4. Population A group of individuals of the same species that coexist in space and/or time

5. Population size / density Rate Birth Death K Born Population size / density Numbers Dying Difference = NET Recruitment S-Shaped Growth Curves Characteristic of intra-specific competition N - Shaped K

6. Community? A group of interacting populations of different species that coexist in time/space

7. Outcomes of interactions between two species Inter-specific Interactions -+Predation --Competition 0+Commensalism 0-Amensalism Species BSpecies A ++Mutualism

8. A community as viewed from a predator-prey perspective A group of interacting populations of different species that coexist in time/space

9. A number of other trophic based units also used Community subsets Guild Communities can have very many interacting populations of different species and to study all of them requires a suite of expert taxonomists at the very least. Community ecologists tend to get around this issue by studying subsets of the community

10. Taxocene

11. Morpho-species

12. Ecosystem vs Community

13. How big is a community?ANY SCALE Broad patterns in terrestrial vegetation can be recognized at the global scale - BIOMES At this scale, climate is the overwhelming factor that limits vegetation

16. How small is a community?

17. Regional Species Pool Evolutionary Processes Physiological Constraints Historic Events Habitat Selection – Habitat Species Pool Dispersal Ability – Geographic Species Pool Local Community Inter-specific Interactions Rules – a species will only be present if: a)It can disperse there b)Conditions and resources allow it to survive c)Predators and competitors etc don’t preclude it Determinants of Community Composition and Structure

18. Course Aims and Structure Objectives: To train students in the basic theories of community ecology To provide students with the necessary field skills to enable them to undertake surveys and identify biological communities To provide students with the necessary skills to enable them to determine those environmental factors contributing to community structure Required Background: Any course on community ecology requires a certain level of background theory and skills - if it is to be successful. For this course, they include a working knowledge of: Measures of central tendency and dispersion MSExcel It is also assumed that students are able to build simple single-species models of population growth and that they have a knowledge of intra-specific competition. As many of you may lack this background, it will be necessary to spend a short period of time completing this work.

19. Approach: The course is a balance between theory, laboratory and field: any person that goes on to work (e.g.) in nature conservation needs to know why data on communities need to be collected, they need to know how to collect the data and then how to analyse the data. They may also need to make informed decisions (often of a management nature) based on the data. As a consequence, any course on community needs to include elements of theory, fieldwork and laboratory simulation, and here the theory and laboratory simulation go very much hand in hand. NB: It is not possible to cover everything in the theory AND develop your field, analytical and report-writing skills. As a consequence, some areas of theory are ignored entirely or are glossed over very superficially. ALL LECTURES AND SUPPLEMENTARY MATERIAL WILL BE PROVIDED ON THE INTERNET AFTER THEY HAVE BEEN PRESENTED

20. Defining a community Summarizing characteristics Examining links Introduction: Definitions Inter-specific Interactions I: Competition Inter-specific Interactions II: Predation Community changes in space and time: Succession Disturbance Effect of Competition in structuring communities Effect of Predation in structuring communities Contents Field & Analytical Theory & Modeling Theory, Modeling and Field

21. Timetable There will be three lectures per week and two practical classes. ALL classes will take place in Z29: it may be necessary to schedule additional classes on Saturday mornings: such classes to start at 08h00. IT IS EXPECTED THAT YOU WILL ATTEND ALL CLASSES ON TIME

22. Assessments and Deadlines Evaluation will take the form of continuous assessment. This continuous assessment is broken up as follows: Class test (33%) + Practical work (67%) = Course Mark Class Tests The Class test will be held on Monday 11 August 2008 at 14h00: Z29. Students will be tested on ALL material covered up to and including that of Friday 8 August 2008. If a re-test is necessary (i.e. more than 35% of the class failed the first test), this will be held on Saturday 16 August 2008 at 08h00 in Z29. ONLY those students that failed the first test will be eligible to sit the re-test, and the better of the two marks will be taken into consideration. Students will be tested on ALL material covered up to and including that of Friday 15 August 2008. Course Mark (60%) + Exam (40%) = Final Mark Prac Exam (30%) + Theory Exam (70%) = Exam Mark

23. Practical Work This includes essays, group-work, worksheets, tests and tutorials. In this course, the practical component will comprise three evaluations. These are listed below as well as their contributions towards the Final mark. PLEASE BE ADVISED THAT FACULTY RULES REGARDING PLAGIARISM AND THE SUBMISSION OF LATE ASSIGNMENTS WILL BE UPHELD Poster – 35% towards Practical Mark, 14.07% to Final Mark Preliminary Deadline – Thursday 7 August 2008 Final Deadline – Wednesday 20 August 2008 Essay – 20% towards Practical Mark, 10.05% to Final Mark Submission Deadline – Monday 25 August 2008 Report - 45% towards Practical Mark, 18.09% to Final Mark Preliminary Deadline – Thursday 31 July 2008 Final Deadline – Monday 8 September 2008

24. Create a poster (size A0) in MS PowerPoint to illustrate one of the following topics: In groups of TWO POSTER 1.Competitive Release 2. Character Displacement 3. Competitive Exclusion 4. Resource Partitioning 5. The effect of resource pre-emption on competition 6. The effect of gaps on competition 7. Apparent Competition 8. Mutualism 9. Commensalism 10. Amensalism 11. Defensive responses of plants to grazing 12. Herbivory, defoliation and plant growth 13. Herbivory and plant fecundity 14. Optimal foraging and diet width 15. Optimal foraging and patch use 16. Pseudo-interference 17. Effect of refuges on predator-prey dynamics 18. Type I, II and III functional responses 19.Primary succession on sand dunes 20.Primary succession on lava flows 21.Secondary succession in abandoned or ploughed fields 22.Secondary succession in forest gaps 23.Succession and Markov-Chain Models 24.Concept of successional climax 25.Competition-colonisation tradeoffs in succession 26.Facilitation in succession 27.Interactions with enemies in succession 28.Resource-ratio hypothesis in succession 29.Vital attributes in succession 30.The role of animals in succession 31.Intermediate disturbance hypothesis in terrestrial communities 32.Intermediate disturbance hypothesis in marine communities 33.The effect of fire on plant communities 34.Parasitism 35.Founder-controlled communities 36.The niche 37.The effect of keystone predators in marine ecosystems 38.The effect of keystone predators in terrestrial ecosystems 39.Community changes linked to seasonality 40.Community changes linked to decomposition

25. TITLE CONCEPT NOTE & DEFINITION Article Details METHODS RESULTS & DISCUSSION Legend * Acknowledgements

26. The audience is undergraduate students – Teaching Tool The poster should be based on a published, peer-reviewed scientific paper that CLEARLY illustrates the concept behind the topic The poster MUST be professional in appearance Rubric based on: Number of words Legends to figures or tables Picture credits Font size Line spacing Scientific notation Spelling Grammar Overall layout Colour and background Cluttered or not Structure & flow of text Tense

27. ESSAY 1)The role of fire in structuring fynbos communities 2) The role of mega-herbivores in structuring savannah communities Essays MUST be no longer than 1 500 words, and MUST be no shorter than 1 200 words: the number of words excludes all references and should be indicated at the end of the report. Essays MUST be typed: font size 12; Times New Roman; sentences with 1.5 line spacing. Essays MUST make reference to at least three journal articles, and CAN refer to a maximum of three text book articles and a maximum of one internet article. Copies of ALL the cited journal articles, appropriate sections of text books and internet sources should be attached to the submitted essay, and the relevant sections (i.e. those pieces of information referred to in the report) MUST be highlighted. Failure to attach supporting documentation will result in the essay being returned to the student, with concomitant penalties for late submission being then enforced. All citations must follow approved procedures – failure to so comply will result in the essay being returned to the student, with concomitant penalties for late submission being then enforced. A rubric will be provided against which essays will be assessed

28. REPORT Rocky shore communities along the NW coast of False Bay, South Africa Prepare a 2 500 word paper on the above topic for submission to the African Journal of Marine Science. The instructions for authors and an exemplar manuscript have been provided to assist you prepare your paper. READ them thoroughly! Reports MUST make reference to at least three journal articles, and CAN refer to a maximum of three text book articles and a maximum of one internet article. Copies of ALL the cited journal articles, appropriate sections of text books and internet sources should be attached to the submitted essay, and the relevant sections (i.e. those pieces of information referred to in the report) MUST be highlighted. Failure to attach supporting documentation will result in the report being returned to the student, with concomitant penalties for late submission being then enforced.

29. The data set that you will use for this exercise was collected from the shore at Dalebrook. ALL the data, in a raw state, can be accessed from the www site. You must prepare the data for analysis yourselves but in so doing, beware of possible species misidentifications. ONE other issues are worth mentioning. How will you deal with replicates from each station samples along the shore? Your report should include (at the very least), a description of changes in animal and plant abundance or cover and diversity across the shore as well as a description of changes in communities across the shore. Credit will be given to those students, whose reports investigate some of the links between community members in a quantitative way.

30. Suitable references could include: Branch, GM and Branch, M (1983) The living shores of southern Africa. Struik Lewis, JR (1964) The ecology of rocky shores. English Universities Press Little, C and Kitching, JA (1998) The biology of rocky shores. Oxford McQuaid, CD and Branch, GM (1984). Influence of sea temperature, substratum and wave exposure on rocky intertidal communities: an analysis of faunal and floral biomass. Marine Ecology Progress Series, 19: 145-151 McQuaid, CD and Branch, GM (1985). Trophic structure of rocky intertidal communities: response to wave action and implications for energy flow. Marine Ecology Progress Series, 22: 153-161 Stephenson, TA and Stephenson, A (1972) Life between tidemarks on rocky shores. Freeman.

31. Pass or Fail? A student is deemed to have passed the course if her/his Final mark (i.e. Coursework + Exam) is ≥50% AND the Exam mark is ≥40% AND the Practical mark is ≥50% Should a student obtain a Final mark of ≥50% AND have a Practical mark of ≥50% BUT have an Exam mark <40%, then that student will get an opportunity to write a Supplementary Exam* Should a student obtain a Final mark of 45-49%, AND the Practical mark is ≥50%, then that student will have an opportunity to write a Supplementary Exam* Should a student obtain a Coursework mark (i.e. Class tests + Practical) of ≥50% AND have a Practical mark of ≥50% AND have an Exam mark of ≥30% then that student will get an opportunity to write a Supplementary Exam* A student who does not meet the above grades fails and is not eligible to sit the Supplementary Exam. A student who fails to get a mark of 50% in the Practical work automatically fails, regardless of the Coursework or Exam mark – such a student not being eligible to sit the final exam. Similarly, a student that fails to obtain a course-work mark of less than 40% is not eligible to sit the final exam. * - Supplementary exams will be held at the end of the examination period. This exam will test the student on ALL the work undertaken in the module.

32. Readings Although there are no prescribed books for this course, the following texts are recommended (especially those in bold- typeface): all are currently placed on short-loan at the UWC library. Begon, M., Harper, J.L. and Townsend, C.R. (1990). Ecology: Individuals, Populations and Communities. Blackwell Scientific Publications, 945pp. Begon, M. and Mortimer, M. (1986). Population Ecology: A Unified Study of Animals and Plants. Blackwell Scientific Publications, 220pp. Krebs, C.J. (1999). Ecological Methodology. Benjamin Cummings, 620pp. Morin. P.J. (1999). Community Ecology. Blackwell Science, 424pp Zar, J.H. (1984) Biostatistical Analysis. Prentice-Hall

33. N t+1 / N t = R = R / {1 + [N t.(R-1)/K]} For a population of organisms showing discrete breeding and a fundamental reproductive rate (R) of 1.145 (per year), determine when the population will reach its carrying capacity of 643 215 individuals if the initial population size in 2007 is 12 individuals. Working in groups of two N t+1 = N t R / {1 + [N t.(R-1)/K]}

34. Assuming that you can ALL project populations growing under the influence of intra-specific competition into the future…….. Length (mm) of cephalothorax of Euphausia superba collected during February 2008 from the Weddell Sea, Antarctica. Calculate the mean cephalothorax length of E. superba in the Weddell Sea during February 2008 and determine the standard deviation, variance, standard error and 95% Confidence limits around your estimate. ALL CALCULATIONS TO BE CONDUCTED “LONG-HAND” 20 MINUTES AND COUNTING!

35. Variance (δ 2 or s 2 ) = Σ (x – x) 2 N-1 Mean (μ or x ) = Σx N Standard Deviation (δ or s) = √δ 2 OR √s 2 95% CI = ??? Standard Error (s x ) = s √N WHY? What is the difference?

38. Identifying or Delineating Communities 1 – physically defined communities Assemblages of species found in a particular place or habitat ARTIFICIAL?

39. 2 – taxonomically defined communities Identified by presence of one or more conspicuous species that dominate biomass and/or numbers, or which contribute importantly to the physical attributes of the community Topographic distributions of the characteristic dominant tree species of the Great Smokey Mountains, Tennessee, on an idealized west-facing mountain and valley BG, beech gap; CF, cove forest; F, Fraser fir forest; GB, grassy bald; H, hemlock forest; HB, heath bald; OCF, chestnut oak-chestnut forest; OCH, chestnut oak- chestnut heath; OH, oak-hickory; P, pine forest & heath; ROC, red-oak-chestnut forest; S, spruce forest; SF, spruce-fir forest; WOC, white oak-chestnut forest. Great Smoky Mountains Tennessee SUBJECTIVE?

40. 3 – statistically defined communities Sets of species whose abundances are significantly correlated, positively or negatively, over space and/or time. Look at numerical and specific composition of samples Determine similarities between samples Look for a pattern in the similarities between samples And so identify communities OBJECTIVELY

41. 4 – interactively defined communities Subsets of species in a particular place or habitat, whose interactions influence their abundance. Only some, and perhaps none, of the species in a physically defined community may constitute an interactively defined community. Hairston (1981: Ecology, 62: 65-72) noted that of the seven species of plethodontid salamander in his study (North Carolina, USA), only the two most common influenced each others abundances: the balance, while ecologically similar, remained unaffected by each others abundance.

42. THE END Image acknowledgements – http://www.google.com