Keynotes
Presentations in 2009
Presentations in 2008
Presentations in 2007
Presentations in 2006
Presentations in 2009
New Indices for Ranking Sites for Conserving Biodiversity.
Honorary Professor Gee Chapman
Simposio Internacional de Ciencias de Mar
2009
Experiment Management of Urban Marine Environments.
Honorary Professor Gee Chapman
III Congresso Latino Americano de Ecologia
2009
Important Issues for Environmental Monitoring.
Honorary Professor Gee Chapman
Petrobras Pty, Brazil
2009
Cooperation and Collaboration in Marine Science.
Associate Professor Ross Coleman
Sydney Institute of Marine Sciences, Delegation of Vice-Chancellors from Chinese Super-8 Universities.
2009
A Mob of Molluscs: Using Limpet Behaviour to Understand Animal Aggregation.
Associate Professor Ross Coleman
Hong Kong University.
2009
Recent Advances in Understanding Grazing as a Major Process Influencing Biodiversity on Rocky Shores.
Emeritus Professor A.J. Underwood
11me Simposio Internacional de Ciencias de Mar
2009
Issues in Experimental Ecology
Emeritus Professor A.J. Underwood
III Congresso Latino Americano de Ecologia
2009
Review of Grazing and Biodiversity on Rock Shores
Emeritus Professor A.J. Underwood
3eme Brasilian National Congress on Ecology
2009
Interactions Between Ecological Science and Environmental Management
Professor Emeritus A.J. Underwood
Petrobras Pty, Brazil
2009
Presentations in 2008
The Ecology of Aggregations.
Associate Professor Ross Coleman
University of Sydney.
2008
Presentations in 2007
Urban saltmarshes: What are we achieving.
Professor Gee Chapman
Invited address, Mountains to the Dunes, Central Coast Regional Landcare Forum, Central Coast
May 18-20 2007
Saltmarshes are intertidal habitats on soft sediments which support a wide variety of plants. Although diverse and very variable from one coast to another, many of small, wiry, bushes, succulents or grasses. Saltmarshes throughout the world are threatened because of large amounts of loss of habitat from both landward and marine disturbances. Many of these are described and illustrated. Although in many parts of the world saltmarshes are nominally protected, they are still being lost which has led to renewed interest in the restoration or rehabilitation of degraded or lost marshes. Rehabilitation can cover a range of activities, from the simple removal of a disturbance through to the addition of structures or components of habitat to the creation of new habitat from scratch. Different aspects of saltmarsh restoration are described and illustrated including (i) large-scale managed realignment along the coastline of Britain, (ii) rehabilitation of degraded saltmarshes using seagrass wrack around Tuggerah Lakes, (iii) the creation of new saltmarsh habitats in inner Sydney. I then discuss the anthropogenic and ecological reasons why restoration projects are undertaken and evaluate how realistic these criteria are with respect to restoration of saltmarshes in urban settings. Finally, I discuss the huge gaps in our knowledge with respect the evaluation of restoration in general; and saltmarshes in particular and the needs for restoration projects to include funds for research and evaluation so that we can start learning from all the many projects undertaken.
Restoration of habitat in urbanised estuaries: practice and theory.
Professor Gee Chapman
Invited Seminar, University of Vigo, Spain
12th July 2007
Despite a world wide emphasis on increased protection of coastal habitats, many habitats and the species within them are continuing to be lost by changes to water quality and more importantly urbanization. Loss or degradation may be due to factors such as eutrophication, or more commonly the loss or reduction of intertidal habitats due to replacement by built structures. Of these, seawalls are the most pervasive, replacing > 80 % of natural habitat in many urbanized estuaries. This has led to increased focus on the need to attempt to actively rehabilitate or restore degraded habitat.
Restoration may be as simple as removing a disturbance, which is illustrated by changes on seawalls when wharves which continually shade them are removed. Alternatively, components of habitat can be added. This is illustrated by two research projects. The first added seagrass wrack to a denuded sandflat on the central coast, thereby increasing cover of saltmarsh plants. The second added indented crevices between sandstone blocks on a seawall at Kirribilli that was being repaired. This increase diversity of intertidal animals and plants on those walls. The extreme end of restoration is creation of new habitat, such as boulder-fields, pools in seawalls or urban saltmarshes. Many studies have shown we are successful at creating habitat, at least for some biota. Many of the major problems with ill-defined aims of restoration and the consequences of this for assessment of its success or failure are discussed.
Restoration may be done for anthropogenic (goods and services, aesthetic value, education, spiritual satisfaction) or ecological (conservation, replacement of lost habitat, enhancement of existing ecological functions), but these are seldom scientifically tested in urban restoration projects. It is necessary to view these aims with a touch of realism when describing small restoration projects within a highly urbanized and altered setting.
Re-engineering altered shorelines to increase intertidal biodiversity in urbanized estuaries.
Professor Gee Chapman
Invited Seminar, University of Santiago de Compostela, Spain
10th July 2007
Urbanization is known to have major environmental impacts but most research has focussed on changes to terrestrial habitats. Many of the larger coastal cities are, however, on the coast, particularly in estuaries and coastal urbanization is expanding faster than are inland towns and cities. Yet changes to coastal habitats is largely ignored when impacts of urbanization are considered. Altering shorelines can lead to intertidal habitats being fragmented and lost, particularly by their replacement by built structures. Of these, seawalls are the most pervasive, replacing > 80 % of natural habitat in many urbanized estuaries. Seawalls have varying slopes and complexities and are built of diverse material. At first glance, they appear to support diverse intertidal biota, but extensive research in Sydney Harbour has shown widespread changes to the intertidal assemblage. This is mainly due to the paucity of mobile animals (urchins, starfish, molluscs, etc.) that live on walls. Numbers do not tell the whole story because at least one species of limpet has very large populations on seawalls, but the animals do not grow large and have reduced reproductive output.
Focus of our research is now not simply to describe changes to assemblages of animals and plants that live on intertidal seawalls compared to natural habitats, but to focus on methods that walls may be built to enhance their value as habitat. Two new walls, at Quakers Hat and White Bay in Sydney Harbour, are evaluating the effects of increasing the slope and thus intertidal area of the wall by providing vertical and horizontal surfaces rather than a flat facade. The provision of indented crevices or flush surfaces between blocks of sandstone at Kirribilli showed indentations could increase diversity and abundances of many taxa at midshore levels. Recent research that provides larger pools in the facades of the walls also shows that these can increase local biodiversity many times, allowing many species that normally cannot live in these habitats to colonize and survive.
Long-term experimental ecology: integrating experimental analyses.
A. J. Underwood
Invited Seminar, Universidade de Compostela, Spain
July
Critical changes to intertidal shorelines in urbanized estuaries: novel ways of improving altered habitat to maintain biodiversity
M.G. Chapman
Invited Seminar, DPI Fisheries, Cronulla
9th August 2007
Until relatively recently, the effects of urbanization of marine habitats has focussed on contamination of water and sediments from disposal, spills and runoff. The loss, alteration and fragmentation of habitats by urban development, long the concern of terrestrial ecologists, have largely been ignored, except for those intertidal habitats dominated by large plants, such as wetlands, mangroves and saltmarsh. Intertidal habitats are limited in extent because they occupy that narrow fringe between the land and the sea subjected to tidal change. They are linear habitats, with strong upshore environmental gradients. Species in intertidal habitats occupy particular habitats, which is set by abiotic conditions and/or biotic interactions. Loss of or changes to intertidal habitats over large scales are therefore likely to affect many taxa, which do not have other habitats into which they can retreat.
Urban estuaries are greatly altered by development and with increasing urbanization; on the coast in particular, this is likely to increase. Of all marine habitats, the intertidal areas have been most affected, with replacement of many natural shores by built structures, including seawalls, groynes, marinas, etc. Although these structures differ markedly from natural shores, cursory examination suggests that they provide useful habitat for intertidal organisms, many of which reach large cover or densities on these structures. Detailed sampling shows that, in Sydney Harbour at least, intertidal seawalls do not provide suitable habitat for many taxa, which either do not live on artificial structures, live at abnormal densities or do not grow large, thus affecting reproductive output.
Comparison of the physical structure of built seawalls compared to rocky shores indicates some major features of habitat that are generally lacking on seawalls. Imaginative engineering may, however, be able to supply surrogates for these habitats. Some of the engineering changes to seawalls that are being trialled in Sydney Harbour will be described, with preliminary data on their effects on intertidal diversity.
Biodiversity on rocky shores: patterns and processes and climatic change
A. J. Underwood
Invited Seminar, Universidade de Vigo, Spain
July
Presentations in 2006
Wetland Education and Training (WET) Program Coastal saltmarshes: recent techniques in their protection, creation and rehabilitation
Chapman, M.G.
Meeting at the Sydney Olympic Park Authority, Sydney, Australia
March 2006
There are many logical issues with measuring success of restoration and rehabilitation and these are not confined to saltmarshes. The myriad of activities that restoration covers has lead to an extensive vocabulary of jargon, with different terms meaning different things from one project or one person to another. It is also based on numerous ecological themes known to be incorrect, such as the restoration of the balance of nature. This talk reviewed some of the current misunderstanding about what we should be able to achieve in any restoration programme as background to more realistic ways of measuring whether it has been successful or not. Then it discussed particular technical issues to do with replication, control and reference locations, spatial and temporal variability, the time scales of restoration and current analytical methods for measuring univariate or multivariate change.
Methods for analysing and interpreting small-scale variation
Chapman, M.G.
7th International Temperate Reef Symposium, University of California, Santa Barbara, California, U.S.A.
26 June to 1 July 2006
Most organisms vary in abundance in space at an hierarchy of spatial scales, although the range over which this occurs vary with size, life-histories, or rates of dispersal of the organisms themselves. Such patterns are well documented for some taxa in some habitats, but not for others. Variability in abundance is equally likely at an hierarchy of temporal scales, depending on local disturbances and balances between processes increasing or decreasing abundances. This has not been well demonstrated, with many reported studies of temporal change confounding spatial and temporal variability at different scales. Demonstrating the scales in time and space at which species show most variability is essential in understanding the processes that most influence distributions of species. It focuses attention on the scales at which hypotheses need to be tested and experiments done to distinguish among competing models. At larger spatial and temporal scales, it is important to distinguish between two sets of processes that cause variable patterns. First, there are processes that only operate at large scales, but the effects of which may vary from place to place or time to time. Second, there is the effect that large-scale variation in local conditions can change small-scale processes. Variation over large scales is undoubtedly influenced by both of these, but they are not always distinguished. Often, one is ignored, because of the preferences of the ecologists. Distinguishing between these requires experimentation to be done and interpreted at multiple scales. Methods of analysing data across multiple scales may use discontinuous or continuous sampling, each of which has advantages and disadvantages. The relative benefits/costs of different approaches will be determined partly by resources and partly by the question being investigated. The best approach will only be identified if there are very clear hypotheses about various processes that may be operating on an assemblage and the scales at which they are most likely to be important.
Long-term wrestling with experimental marine ecology: thoughts, opinions and hopes
Underwood, A.J.
7th International Temperate Reef Symposium, University of California, Santa Barbara, California, U.S.A.
26 June to 1 July 2006
There are, it turns out, relatively few advantages from being able to keep doing your Ph.D. over several decades. One is that you discover how unrealistic is a short-term (often considered reasonable length) study over 3 – 4 years. That this matters is increasingly becoming clear. What to do about it is increasingly opaque. A second is that you always have more data than most people (i.e. ecologists who are even more longevous are generally sparser). This is a comfort when the words “generally” or “usually” are bandied about. The best advantage is that you do learn how not to do things, so, in theory, can offer useful advice to newer ecologists. The disadvantages, in contrast, are numerous. They include the frustration of trying to fund long-term projects (which is as equally frustrating as are short-term projects, but more likely to be assessed as having already been done). They also include the phenomenon that someone starting out can apparently claim to be doing your long-term project as a piece of original research and defending this view on the grounds that they weren’t born when your project started. How to integrate long-term and more proximate projects will be discussed in the context of what I might have learned in 40 years of doing the same things. Finally, long-term projects do not always come into existence because of failure to publish them when they ended as short-term projects. They can be planned – but probably only realistically by younger ecologists!
Award presented "for lifelong service and contributions to Marine Sciences"
Impacts of human development on intertidal molluscs.
Professor A.J. Underwood
Molluscs 2006, University of Wollongong
December 2006
Increased disturbance, loss and change of habitat, harvesting, alterations of climate and numerous types of contamination are the apparently inevitable consequences of expansion of human populations. This is most apparent in coastal areas around the world because that is where most people live. In response to this conspiracy of environmental insults, measuring and understanding ecological changes and, ultimately, predicting these changes are critical scientific responses to the rash of humans infecting the planet.
To illustrate progress in such ecological research programmes, examples will be discussed of different types of study. Change of habitat by replacing natural intertidal areas by seawalls is widespread. The fauna on seawalls are, however, not as diverse as on nearby intertidal shores (even vertical ones). Worse, even though populations might be conserved by provision of artificial habitats, there will be problems because their reproduction is not maintained. Harvesting can have profound impacts, as will be illustrated by decreased diversity of invertebrates (including molluscs) in response to a fishery for urchins. The coming (and already started) debacle of global climate change may devastate intertidal molluscs because of increased sea-level and air-temperature. These will be illustrated using results from experimental studies. Larger-scale patterns in response to urbanization require proper quantitative sampling of diversity. Some of the problems of interpretation will be outlined. The potential use of gastropods to measure changed environments will be outlined.
Being a progress report, definitive answers will be sparse – but at least it is known where the research programmes are going and why and how they can be used to help underpin managerial decisions (where management is actually possible).
Ecological impacts of estuary management with respect to constructing seawalls at the entrance to Tuggerah Lake.
Professor M.G. Chapman
Central Coast Environmental Education Workshop, Forum 1: The Great Seawall Debate, Wyong Shire Council, Quay West Resort Magenta Shores, The Entrance, NSW
30th September, 2006
Tuggerah Lakes is one of many ICOLS in New South Wales; estuarine systems which alternately have open or closed access to the sea. Many of these are managed to keep the entrance open. A number of different examples of ICOLS was presented. These estuaries are typically very shallow, with poor tidal flushing and dominated by soft sediments, but are also heavily used for fishing, recreation and increasing urbanization. This combination of environmental conditions and human usage has led to varying environmental problems in ICOLS and conflict with stakeholders who perceive different use of these habitats.
The particular environmental issues discussed in this talk, with respect to current problems (perceived or real), management and the proposed permanent opening of the entrance using seawalls included (i) problems with macro-algae blooms and decomposition of vegetation along the shoreline, (ii) potential loss of valuable intertidal habitat, such as saltmarshes, (iii) spread of mangroves, (iv) potential changes to biological processes within seagrass and their flow-on to other components of the environment. Finally, the seawall as a habitat in its own right was described, with respect to species that might settle and live on the wall and species that might accumulate around the wall in the open water.