Monitoring river health in the wet–dry tropics: strategic considerations, community participation and indicators

Authors: Simon Townsend, Chris Humphrey, Satish Choy, Rebecca Dobbs, Michele Burford, Richard Hunt, Tim Jardine, Mark Kennard, Jeff Shellberg, Emma Woodward © Griffith University 2012 ISBN: 978-1-921576-67-6 Printed by Griffith University

Copyright This publication is copyright. Apart from any fair dealing for the purpose of private study, research, criticism or review as permitted under the Copyright Act 1968, no part may be reproduced, by any process, without written permission from the publisher. Enquiries should be made to: Charles Darwin University c/– Tropical Rivers and Coastal Knowledge (TRaCK) Casuarina Campus, Building Red 1 Level 3, Darwin NT 0909 Australia TRaCK brings together leading tropical river researchers and managers from Charles Darwin University, Griffith University, the University of Western Australia, the Commonwealth Scientific and Industrial Research Organisation, James Cook University, the Australian National University, Geoscience Australia, the Environmental Research Institute of the Supervising Scientist, the Australian Institute of Marine Science, the North Australia Indigenous Land and Sea Management Alliance, and the governments of Queensland, the Northern Territory and Western Australia. TRaCK received major funding for its research through the Australian Government’s Commonwealth Environment Research Facilities initiative; the Australian Government’s Raising National Water Standards Program; Land and Water Australia; the Fisheries Research and Development Corporation; and the Queensland Government’s Smart State Innovation Fund.

Disclaimer TRaCK has published the information contained in this publication to assist public knowledge and discussion, and to help improve the sustainable management of Australia’s tropical rivers and coasts. Where technical information has been prepared or contributed by authors external to TRaCK, readers should contact the author(s) and conduct their own enquiries before using that information. No person should act on the contents of this publication as to matters of fact, opinion or other content without first obtaining specific independent, professional advice that confirms the information contained within this publication. Although all reasonable efforts have been made to ensure that the information in this publication is correct, matters covered by the publication are subject to change. Griffith University does not assume and hereby disclaims any expressed or implied liability whatsoever to any party for any loss or damage caused by errors or omissions, whether these errors or omissions result from negligence, accident or any other cause.

Acknowledgement This project was funded by the Australian Government through the National Water Commission’s Raising National Water Standards Program.

To find out more about TRaCK, contact us via one of the following methods: Web: www.track.org.au/ Email: [email protected] Phone: 08 8946 7444 Cover photos (clockwise, starting top left): Department of Land Resource Management (top left and bottom photo), D Warfe, P Featherston Authors: Simon Townsend, Northern Territory Department of Land Resource Management, Chris Humphrey, Environmental Research Institute of the Supervising Scientist, Commonwealth Department of Sustainability, Environment, Water, Population and Communities Satish Choy , Queensland Department of Science, Information, Technology, Innovation and the Arts Richard Hunt, consultant (formerly Queensland Department of Environment and Resource Management) Rebecca Dobbs, Centre of Excellence in Natural Resource Management, The University of Western Australia Michele Burford, Tim Jardine, Mark Kennard & Jeff Shellberg, Australian Rivers Institute, Griffith University Emma Woodward, CSIRO Ecosystem Sciences Contents Acronyms and abbreviations ii

Foreword iii

Executive summary iv

1 Strategic considerations for river health monitoring 1 1.1 Introduction 2 1.2 The wet–dry tropical environment: climate, river systems and people 3 1.3 Challenges for river health monitoring in the wet–dry tropics 5 1.4 Monitoring objective 7 1.5 Monitoring principles 6 1.6 Pressure–stressor–response framework for monitoring 7 1.7 The Framework for the Assessment of River and Wetland Health (FARWH) 7 1.8 A two-tiered approach to monitoring 9 1.9 Temporal variability 11 Seasonal variability 11 Interannual variability 12

2 Indicators 14 2.1 River metabolism 15 2.2 Phytoplankton and benthic algae 16 2.3 Water quality 17 2.4 Freshwater fish 17 2.5 Macroinvertebrates 18 2.6 Ecogenomics 20 2.7 Time-lapse photography 20

3 Community monitoring 23 3.1 A Kimberley case study 24 3.2 Trial Indigenous participatory monitoring program 26

References 29

Monitoring river health in the wet–dry tropics i Acronyms and abbreviations ANZECC Australian and New Zealand Environment Conservation Council ARMCANZ Agriculture and Resource Management Council of Australia and New Zealand AusRivAS Australian River Assessment System BACI Before–After Control/Impact ER Ecosystem Respiration FARWH Framework for the Assessment of River and Wetland Health GIS Geographic Information System GPP Gross Primary Production MODIS Moderate-resolution Imaging Spectro-radiometer NAILSMA North Australia Indigenous Land and Sea Management Alliance P/R Gross primary production to ecosystem respiration ratio PSR Pressure–Stressor–Response (framework) RNA Ribo-Nucleic Acid SEAP Stream and Estuaries Assessment Program SIGNAL Stream Invertebrate Grade Number Average Level TRaCK Tropical Rivers and Coastal Knowledge TRARC Tropical Rapid Assessment of Riparian Condition TRIAP Tropical Rivers Inventory and Assessment Project WEP Waterways Education Program WOC Working on Country [Program]

ii Monitoring river health in the wet–dry tropics Foreword At a national level, research into On 16 August 2011, a workshop Following the August workshop, monitoring river health was initiated was held in Brisbane to identify another workshop was held on in the early 1990s by the Australian the implications of TRaCK research 1 September 2011 at Mary River Government with the National River for river health monitoring in the Park (Northern Territory), as part Health Initiative program, which wet–dry tropics. The workshop was of a NAILSMA I-Tracker forum. The produced most notably the Australian attended mainly by researchers and workshop was attended by about River Assessment System (AusRivAS) government agency TRaCK partners. 60 people, mostly Indigenous land macroinvertebrate models (eg Smith The attendees were Michele Burford, managers and representatives of et al. 1999). This nationwide data Mark Kennard, Simone Langhans, these groups. TRaCK researchers who base contributed to the 2001 audit Francis Pantus and Tim Jardine from led the monitoring component of of river health (Norris et al. 2001), Griffith University; Simon Townsend the workshop were Michael Douglas which however only included a small with affiliations to Charles Darwin from Charles Darwin University and portion of the wet–dry tropics. The University and the Northern Territory Emma Woodward from the CSIRO. audit was followed by more specific Department of Land Resource tropical river research between Management; Rebecca Dobbs from 2006 and 2008 with the Tropical the University of Western Australia; Rivers Inventory and Assessment Chris Humphrey and Simon Nally Project (TRIAP), which developed from the Australian Government an integrated information base for Department of Sustainability, the assessment of river status (see Environment, Water, Population Finlayson and Lukacs 2008). and Communities; Satish Choy, The Tropical Rivers and Coastal Niall Connolly and Pru Fleming Knowledge (TRaCK) consortium from the Queensland Government; undertook research between Mike Braimbridge from the 2005 and 2010 that spanned a Western Australian Department range of topics relating to cultural, of Water; and Rod Kennett and environmental and economic aspects Erica McCreedy from the North of tropical rivers. TRaCK’s primary Australian Indigenous Land and Sea objective was to provide knowledge Management Alliance (NAILSMA). to governments, communities and The workshop was organised by industry for the sustainable use of Kathy Carter (Griffith University) rivers in the wet–dry tropics. The and Amy Kimber (Charles Darwin program was followed by a year University). consisting of six ‘synthesis and adoption’ topics, which included monitoring river health. This report is based on the findings of two workshops and contributions of TRaCK partners.

Monitoring river health in the wet–dry tropics iii The key objective for long-term Monitoring by community groups Executive summary monitoring espoused in this report is and landholders can contribute River health is in generally good the early detection of anthropogenic to and complement surveillance- condition in the Australian wet–dry effects that may potentially degrade type river health monitoring. It tropics compared to the more river health. This concurs with the can contribute to monitoring by developed parts of Australia. The approach of the Australian and New providing data (eg water quality), health of rivers is nevertheless Zealand Environment Conservation and complement surveillance modified by anthropogenic activities Council and the Agriculture and monitoring by focusing effort on due to diffuse catchment pressures; Resource Management Council of local management issues beyond notably grazing, feral animals and Australia and New Zealand (ANZECC- the resources of catchment-wide fire, and more localised pressures ARMCANZ 2000). This approach is surveillance monitoring. Case from mining and agriculture. especially significant in the wet-dry studies of river health monitoring Residents of the wet–dry tropics tropics to provide warning of river by Indigenous communities have high expectations that the health degradation and thereby highlight the advantages of cross- rivers will remain healthy, and view avoid the social and economic costs cultural exchange of information any degradation, even if minor on a of restoration. In many parts of and the importance of building national scale, as being significant Australia monitoring is directed to on established social networks. An and the possible start of long-term assessing river health responses to assessment of the capacity and degradation. restoration activities. Early detection willingness for community-led Monitoring river health in the however requires adequate resources, monitoring is important. Trials of wet–dry tropics faces significant which are severely limited in the indicators tested by community challenges. The vast area, small north, and a sound knowledge of the groups found photo-point monitoring population base and limited all- desired reference condition so that to be the most successful method. weather road infrastructure impose natural inter-annual variability can While community-based monitoring resource and logistical challenges. be distinguished from anthropogenic is driven by the community, there is The high seasonality of rainfall also impacts. To address the resource an important role for scientists in imposes constraints on monitoring. constraint, a two-tiered approach assisting groups to select appropriate In the wet season most rivers are to monitoring is proposed. This indicators and methods for inaccessible. In the dry season many approach acknowledges that not measuring and monitoring change. rivers cease flowing while others everything, everywhere, can be Monitoring river health is an reduce to a series of disconnected monitored. The first tier would report essential element of the adaptive pools or waterholes. Some rivers and on the pressures at a catchment- management cycle, and can streams are groundwater-fed and wide scale and make use of GIS and provide early warning of river flow year-round. other spatial data, while the second health degradation. The logistical, tier would be undertaken at a much River health monitoring can be resource and capacity constraints smaller scale, or case study level, to considered a societal activity, of monitoring, and the unique detect early degradation. Second-tier founded on principles of environment, necessitate the results could be extrapolated to the collaboration, communication, development of a monitoring system larger catchment if a relationship scientific credibility, transparency, tailored to the wet–dry tropics. between pressure and river health is community participation, education, established. and—importantly—relevance to management. The Framework for The wet–dry season transition the Assessment of River and Wetland period is proposed as the best Health provides a comprehensive time to sample macroinvertebrate outline for surveillance-type river communities, a widely-used indicator health monitoring, underpinned by for monitoring and assessing river the pressure–stressor–(ecological) health. This is the period of highest response framework that seeks to species diversity, and is also when link anthropogenic pressures to river wastewater discharges may have health. their highest impact. Monitoring river health using water quality, whole- of-river metabolism, phytoplankton, macroinvertebrates, ecogenomics and fish as indicators is discussed in this report, along with the use of time- lapse photography to monitor animal visitation to waterholes, aquatic plant cover, and erosion.

iv Monitoring river health in the wet–dry tropics Strategic considerations for river health monitoring This report focuses on the In the northwest part of Western 1.1 Introduction surveillance monitoring of river Australia, annual monitoring of Monitoring is one component health, where health refers to the fish, macroinvertebrates, vegetation in the adaptive management river’s ecological integrity (see Norris and water quality is done in the cycle (Figure 1). The evaluation of and Thoms 1999). To be effective, Ord Region to support the Ord monitoring improves understanding surveillance monitoring needs to be River allocation plan. The Western for better planning and policy undertaken over long periods, with Australian Department of Water development, which leads to a decadal perspective to address currently maintains and operates 26 management actions. Underpinning long term climate patterns including hydrometric gauging stations and river health management are climate change, as well as potential 32 rainfall gauges across the Ord objectives to maintain or restore lags in anthropogenic impacts on and Fitzroy river catchments. These the environmental values or river health. stations provide data on water level, beneficial uses of a river system. We discuss strategic considerations flow and irregular water quality Most monitoring is driven by state to river health monitoring, based measurements. A small number and national government policy and largely on the research of Risby et of Indigenous ranger groups are legislation, and undertaken by mainly al. (2009) and Dixon et al. (2011), currently initiating monitoring state agencies. However, industry, community participation and programs to assess the implications natural resource and catchment potential indicators. Community- of management actions for river management boards, as well as the based river health monitoring, health. Elsewhere in the Kimberley, local government, community groups, including that undertaken by specific monitoring of aquatic landholders and Indigenous groups Indigenous ranger groups, can health using indicators such as also conduct monitoring. complement surveillance monitoring macroinvertebrates and fish are only Monitoring can fall into three by government agencies. We describe of short term duration and largely ad broad categories: surveillance, a participatory river monitoring hoc. However, a number of long-term compliance and performance program trialled by four Indigenous studies have been undertaken on key monitoring. Surveillance monitoring groups. species (eg Fitzsimmons et al. 2009). refers to broad scale monitoring Very few catchments in the wet–dry Compliance monitoring can that aims to assess river health at tropics undergo surveillance potentially contribute to surveillance a large scale, typically catchment monitoring of river health. In the monitoring. In the Northern based. Compliance monitoring is Northern Territory, river water quality Territory, compliance monitoring is undertaken as a legal requirement, and macroinvertebrate communities mainly undertaken by the mining typically associated with a licence; for are monitored in the Darwin Harbour industry, with at least five issued example, to extract water for human catchment (eg Fortune et al. 2009), licences that require river health and agricultural uses or discharge and in Alligator Rivers Region streams monitoring. In Western Australia, wastewater to a river. Performance (eg Supervising Scientist 2011). In compliance monitoring is done for monitoring provides information the Daly catchment, monitoring has water abstraction and wastewater about a specific management action, been sporadic, comprising several discharge by the mining and such as riparian restoration along a one-off, short-term surveys (Schult & agricultural sectors, notably the nominated stream reach. Townsend 2012). Argyle Diamond Mine and the Ord River Irrigation Area. In northern Queensland, surface water and groundwater quantity and quality are assessed regularly and reported periodically (eg DERM 2011a, McNeil & Raymond 2011). Other indicators, such as macroinvertebrates, were previously monitored (eg Conrick et al. 2001, DNRW 2006) but more comprehensive monitoring based on the pressure–stressor–response framework and risk assessment is currently used (DERM 2011b,c). In addition, environmental flow assessments based on ecological assets that have critical links to flow are carried out in water planning areas (eg DERM 2011d). Compliance monitoring is also undertaken by the mining industry. Figure 1 The adaptive management cycle showing monitoring and evaluation. Source: Queensland Department of Science, Information, Technology, Innovation and the Arts.

2 Monitoring river health in the wet–dry tropics The wet–dry tropical region’s 1.2 The wet–dry tropical environment: population is low (approximately climate, river systems and people 240 000 people), with an average density of about 0.1 persons/km2. The wet–dry tropics region of Australia is vast. It represents 15% of the total This is low compared to the more land mass, or 1.2 million square kilometres, and for the purposes of the Tropical developed parts of Australia Rivers and Coastal Knowledge (TRaCK) program comprised catchments that (eg Victoria has 23 people/km2). drain into the Coral Sea, Gulf of Carpentaria and the Timor Sea (Figure 2). Most of the population resides in TRaCK research focused on the Fitzroy, Ord, Daly, Flinders and Mitchell River Darwin and its hinterland (120 000 catchments, and Darwin Harbour. The Queensland Government also undertook people), Mt Isa (22 000 people), research in the Burdekin catchment, which drains into the eastern seaboard, Broome (16 000 people), Katherine and lies outside the TRaCK research area but has a wet-dry tropical climate. (10 000 people) and Kununurra (7500 people). The remainder of the population live in small communities, many of them Indigenous. There are large areas of the wet–dry tropics that are regarded as ‘very remote’ 0’0’’S 0’0’’S 0 0 according to the Accessibility/ 10 Timor Sea 10 Remoteness Index of Australia DARWIN (DoHA 2001). Despite this Coral ARNHEM CAPE remoteness, the region supports Gulf of Sea Daly LAND YORK Carpentaria PENINSULA substantial industry (eg mining, grazing, fishing, tourism) and Mitchell THE KIMBERLEY heritage values (eg Indigenous art, BROOME Ord CAIRNS dinosaur fossils). Fitzroy The landscape of the wet–dry tropics 0’0’’S 0’0’’S 0 0 is highly weathered, of low relief, and 20 NORTHERN Flinders 20 WESTERN TERRITORY dominated by savanna grassland AUSTRALIA N and woodlands. Low-intensity cattle Kilometers QUEENSLAND grazing is the main land use, while 0 130 260 520 780 1,040 Indigenous and conservation uses are the next most common uses. Figure 2 The wet-dry tropics. The TRaCK research area comprised catchments with rivers that flow into the Gulf of Carpentaria and the Timor Sea. Rivers that flow into the Coral Sea were not part More intensive land uses, such as of the TRaCK research area. agriculture and mining, represent less than 2% of the land area (Woinarski et al. 2007). Intensive Rainfall within the wet-dry tropics is highly seasonal, with annual rainfall agriculture is currently concentrated higher along the coastline (1200-1500 mm) than inland areas (300–400 mm). in parts of the Ord and Daly river Most rain falls during the wet season months of December to March. catchments, and will extend to the The two transition periods (October–November and April–May) are Keep River catchment through the characterised by convective storms, while rainfall is negligible during the Ord River Irrigation Scheme Stage 2 dry season (June–September). development. Intensive agriculture This highly seasonal pattern of rainfall produces predictable seasonal patterns tends to be on a small scale in the of river flow (Kennard et al. 2010). High flows and floods occur during the Gulf of Carpentaria catchments; wet season, though water levels and the extent of flooding varies between for example, sugar cane crops in years. Dry season flow depends on the extent of groundwater supply, and may the upper Mitchell River catchment. extend through the dry season or cease shortly after the last storms of the Fire is a significant landscape-scale wet–dry transition period. During the dry season, many rivers reduce to a series management issue, with fires more of disconnected pools. This highly seasonal flow regime underpins the river’s frequent and more intense than the ecology (Douglas et al. 2005, Warfe et al. 2011). Most rivers are unregulated, traditional Indigenous management although notable exceptions are impoundments on the Ord, Leichhardt and of the land (Russell-Smith et al. 2003). Darwin rivers. Groundwater supplies water for irrigation, stock and potable domestic purposes, with the potential to significantly reduce dry season flow.

Monitoring river health in the wet–dry tropics 3 Pusey et al. (2011) has recently reviewed threats to river health in the wet–dry tropics (Figure 3), which were: • grazing • cropping and agriculture • altered flow regimes • altered fire regimes • tourism and recreational activities • physical infrastructure (eg barriers • feral animals • industrial, mining and urban to fish movement) • weeds impacts • climate change.

Despite these threats, river health in the wet–dry tropics is generally good compared to the rivers in southern Australia (Pusey et al. 2011). However, there is degradation due to diffuse impacts (eg feral animals, grazing, irrigation) and point sources (eg wastewater discharge from mines).

Cattle track network under the riparian canopy Riparian weed Passiflora foetida smothering saplings

Cattle access to the stream edge Past cattle bank and stream access

Stream edge trampled by cattle Stream edge trampled by pigs

Figure 3 Cattle, feral animal and weed disturbance to the riparian zone and stream channel Photos: I Dixon

4 Monitoring river health in the wet–dry tropics 1.3 Challenges for river health monitoring 1.4 Monitoring in the wet–dry tropics objective The vast land area, scant road network and climatic extremes of the wet–dry Clearly stated objectives and tropics, combined with the small population, pose logistical challenges to hypotheses are the basis of river monitoring. Long distances need to be travelled to undertake fieldwork, which health monitoring programs by imposes a time and financial cost. The road network is not extensive, with only providing an articulated purpose. major roads generally sealed. This restricts vehicular access to watercourses, In the wet–dry tropics, long term especially low order streams. In the wet season, unsealed roads can become monitoring for the early detection impassable, and sealed roads can be periodically flooded. In the dry season, of river health degradation, as when vehicular access becomes possible, many rivers and streams cease advocated in national guidelines flowing and become dry riverbeds or a series of disconnected pools that for river health assessments dry out. (ANZECC–ARMCANZ 2000), is River health monitoring has tended to occur during the dry season when recommended. This primary objective vehicular access is possible, and been biased towards large, high-order rivers seeks to detect degradation before such as the Daly, Mitchell, Fitzroy and Ord rivers. A perennial flow regime it becomes ecologically significant, dominates the high order rivers of the Daly catchment, but represents a small thereby avoiding undesirable proportion of the total drainage network (Figure 4). Small, lower order streams social impacts, and costly river and have not been monitored in proportion to their contribution to the total catchment restoration. Importantly, length of the drainage system. residents of the wet–dry tropics have high expectations that There is some evidence that perennial small streams are more vulnerable to their rivers will remain healthy cattle and feral animal impacts than larger rivers (Dixon et al. 2011); hence, and view any degradation, even their omission in monitoring programs may produce misleading assessments. if minor on a national scale, as Vehicle access to such streams, even in the dry season, can be difficult and being significant and the possible time consuming, especially in the absence of bush tracks. Moreover, to select start of long-term degradation. flowing sample sites an understanding of stream flow regimes (perennial or Additionally, for Indigenous people, seasonal flow) is required but often lacking and not necessarily accurately the environmental values of a healthy represented on topographic maps. river are inseparable from cultural values and underpin a wide range of cultural activities. A secondary objective that is closely 3000 aligned with the main objective is to monitor for the incremental 2500 degradation of river health. This objective provides a spatial and temporal context to the primary 2000 objective. River health degradation on a catchment scale typically 1500 results from the cumulative impact of multiple pressures (fire, grazing, feral animals, point sources and 1000 weeds) operating at a range of Stream length (km) Stream spatial and temporal scales. Single 500 anthropogenic disturbances are rare with the possible exception of pollution from acid mine drainage. 0 The adoption of an early detection 3 4 5 6 7 objective, however, has design and Stream order resource implications. To detect small degradations in river health with Intermittent flow Perennial flow reasonable confidence, replication is required to overcome natural spatial Figure 4 Daly catchment perennial and intermittent flow stream lengths. Stream order and length and temporal variability. Using more were obtained from a National Land and Water Resource GIS (Dixon et al. 2011), which omitted 1st and 2nd order streams. The perennial flow category was based on GIS classification, Tickell (2008) and data replicate sites or sampling occasions supplied by the Department of Land Resource Management. increases the likelihood of detecting true river health degradation, although with diminishing returns at ‘high’ sample size.

Monitoring river health in the wet–dry tropics 5 In statistical terms, replication • Communication. All stakeholders • Community participation and increases the power to detect an and the community have an education. The community is effect, which minimises type I and II interest in river health, and want often keen to participate in, error rates.1 Increasing replication, to know the health of rivers in and contribute to, monitoring however, requires more resources. their catchment. Communication programs. Community-derived The early detection of river health needs to be tailored for a range of data do not need to feed directly degradation also requires the audiences, from technical reports into the scientific design of a selection of indicators responsive to to plain English summaries, such as program, and may address local possibly low levels of anthropogenic report cards. river health issues not addressed pressure. Indicator choice should • Scientific credibility. Monitoring by a scientifically designed be based on a sound conceptual must be conducted in a program. Community monitoring, understanding of the relationship scientifically rigorous manner. nevertheless, should be reported between pressures and the It should be underpinned by a and be part of the collaboration. environment, and ideally supported sound understanding of river Community participation offers by experimental evidence that ecology based on a program of opportunities for river health provides an insight into the threshold research that includes the impact monitoring in the remote parts of and rate of indicator response to a of anthropogenic pressures. A the wet–dry tropics that would be pressure. credible monitoring program too costly to otherwise undertake. 1 Participation can be valuable in A type I error incorrectly classifies a site as impaired. A comprises articulated objectives type II error incorrectly classifies a site as unimpaired. and hypotheses, the selection of itself by facilitating education, responsive indicators, adequate thereby informing the public and design, and data analysis and land managers about river health 1.5 Monitoring interpretation. Peer review should management issues, and building capacity and social networks. principles be sought at all times. • Transparency. To facilitate • Relevanto t management. River River health monitoring should be credibility with all stakeholders health monitoring is a component more than the collection of site- and the community, and promote a of the adaptive management specific data to meet the legal and collective approach to river health cycle and needs to be relevant policy obligations of governments assessment, monitoring should to management. The pressure– and other organisations. Rather, be transparent. Information about stressor–response (PSR) framework, monitoring can be viewed as a river health monitoring—including, discussed below, seeks to link the societal activity, where governments for example raw data—should anthropogenic pressures—the typically play leadership and be made publicly available. primary focus of management facilitation roles. This more Transparency provides a basis to actions—to river health. comprehensive view is underwritten build trust between monitoring • Resource efficient. The resources by the following desirable qualities of organisations, stakeholders and the for river health, especially in the a monitoring program, referred to as wider community. wet–dry tropics, are significantly principles: limited, and should be allocated • Collaboration. Monitoring is to provide the most valuable undertaken by governments, information for the cost incurred. industry, landowners and communities, and should aim to be a collective activity and, whenever possible, make use of all monitoring data to contribute to river health assessment. Collaboration requires human resources, and includes data management.

6 Monitoring river health in the wet–dry tropics 1.6 Pressure–stressor–response 1.7 The Framework framework for monitoring for the Assessment The pressure–stressor–response (PSR) framework provides a conceptually of River and comprehensive and potentially diagnostic approach to surveillance monitoring (Figure 5). The framework seeks to link the following: Wetland Health • anthropogenic pressures on the environment (also referred to as threats) (FARWH) • the biophysical stressors that collectively drive river ecology The FARWH was trialled in the • ecological attributes. wet–dry tropics by TRaCK and the Queensland Government (Dixon et The framework is based on a conceptual understanding of the effect pressures al. 2011, the Queensland Government have on riverine ecological health. 2011e), and was supported by the Figure 5 provides a simplistic example of the PSR framework. In the first National Water Commission (NWC example, clearing native vegetation constitutes a pressure—it increases 2011). the catchment’s vulnerability to erosion. During the wet season, run-off can The FARWH provides a transport sediment to the river, increasing the concentrations of suspended comprehensive approach to river sediment and reducing the amount of light available for photosynthesis health monitoring, and concurs with by algae in the water column and plants on the riverbed, hence reducing the PSR framework. It comprises the amount of plant biomass. The second example links groundwater six themes (Figure 6): (1) catchment extraction for irrigation to reduced dry season flows, and the habitat area disturbance, (2) hydrology, (3) water for invertebrates and fish. Rarely, however, is there a simple link between a quality, (4) physical form, (5) fringing pressure, stressor and ecological response, except perhaps in the case of toxic zone, and (6) aquatic biota. pollutants. Instead, there is typically more than one pressure, which affects multiple stressors to potentially produce a range of ecological responses. Each theme is scored between 0 and 1, where 0 indicates an extremely

impacted or degraded condition, and 1 is a reference condition. Each theme can comprise several subindices that Example 1 Example 2 combine to a score between 0 and 1, which are then integrated across themes to provide a single river Land Irrigated Pressures health score for a catchment. Sample clearing agriculture sites are ideally selected to represent the drainage system over a range of stream orders, and the natural Suspended Dry (eg geological) and anthropogenic Stressors sediment season (eg land use) influences. The value concentration flows of the FARWH lies in its conceptual basis and the detailed information that underlies the scores, which can be lost through the numerical Amount of algae Total numbers aggregation and integration process. Ecological of aquatic and aquatic The FARWH does not prescribe responses plants insects and fish in rapids indicators for each theme or sub- theme. This provides flexibility for catchment or region specific Figure 5 Two simple examples that show the link between pressure, stressor and ecological response. pressures, stressors and ecological Source: Northern Territory Department of Land Resource Management. response indicators to be selected. The PSR framework underpins the Framework for the Assessment of River For example, the area burnt by fires and Wetland Health (FARWH), discussed next, and is embedded within the was included in the wet–dry tropical Queensland integrated monitoring framework (DERM 2010, 2011c). FARWH catchment disturbance index, but is not included in other frameworks.

Monitoring river health in the wet–dry tropics 7 FARWH (0-1)

Catchment Hydrological Water Physical Fringing Aquatic disturbance disturbance quality form zone biota (0-1) (0-1) (0-1) (0-1) (0-1) (0-1)

1) Land use 1) High flow 1) EC 1) Bank stability 1) Riparian 1) Macro- 2) Fire 2) Low flow 2) pH 2) Connectivity vegetation invertebrates i) Catchment 3) Proportion of 3) DO i) Spatial 2) Aquatic weeds ii) River zero flow 4) Turpidity integrity 3) Fish corridor 4) Variation 5)P FR ii) Nativeness i) Native 5) Season 6)P T iii) Integrity ii) Exotic period 7) Nitrate iv) Age structure 8)N T v) Details

DO = dissolved oxygen; EC = electrical conductivity; FRP = filterable reactive phosphorus; TN = total nitrogen; TP = total phosphorus

Figure 6 Framework for the Assessment of River and Wetland Health (FARWH).

The most significant findings from • Most fringing (riparian) zone • When working over large and the wet–dry tropical trials of the vegetation in the Western remote areas, both spatial and FARWH are listed below (see DERM Australian, Northern Territory and temporal logistic and resourcing 2011e, Dixon et al. 2011): Queensland wet–dry tropics has issues resulted in an insufficient • The Flow Stress Ranking, not been cleared. The condition of number of test and reference developed for the Victorian river this zone can, however, be degraded sample sites to obtain adequate health program, can be applied by weeds, fire and grazing, which statistical power (eg Burdekin River (Figure 7) with minor adaption to are not detected by remote sensing catchment). This led to a lack of accommodate wet and dry seasons. methods. confidence in certain indicators, • Macroinverebrate Australian River particularly those under the ‘water • Gr ab or spot water samples are likely quality’ theme. to miss short-term pollution events. Assessment System (AusRivAS) and For example, plumes of highly turbid fish observed/expected scores were • High levels of natural temporal 2 water were only detected with weakly related (r ~10–15%) to the variability in geographic areas, such continuous logged monitoring when intensity of cattle impacts in the as the Burdekin River catchment, cattle regularly disturbed a stream Daly and Fitzroy rivers. provide a constraint to meaningful in the afternoon; grab samples in • Diel-dissolved oxygen and condition assessments based the morning missed these events. temperature measurements on the snapshot approach. To Continuous monitoring is preferable to monitor river metabolism address statistical issues when to grab samples, and is also best for (photosynthesis and respiration) reporting at different spatial the diel-dependent (variable over in streams sometimes produced scales or using different sample the day) variables (dissolved oxygen, ‘unusual’ dissolved oxygen curves sizes, it is suggested that different temperature and pH). with a night-time maximum that power/confidence levels are used were attributed to the influence of for analysis (appropriate to the • The Tropical Rapid Assessment of spatial scale or sample size). Risk Riparian Condition (TRARC) required large, probably thermally stratified pools upstream, and precluded assessment could be used to reference site data to be applied to the establish the power/confidence FARWH fringing zone theme. TRARC the calculation of whole-of-river metabolism. The computation of level that reflects the priorities sub-indices were not correlated to within and between catchments. independent measures of cattle and metabolism in small streams with feral animal impacts, although this relatively large pools is problematic. • Remote sensing and GIS can may reflect the localised nature of • Reference condition for the wet–dry improve assessments over these impacts compared to the 200 tropics has not been extensively large areas. m riparian reach surveyed. A subset monitored, nor has it been well of TRARC sub-indices, using raw data defined. This limited the application rather than categories, may improve of the FARWH. the sensitivity of riparian condition assessments.

8 Monitoring river health in the wet–dry tropics 3000

2500

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0 Sept Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug

Natural Current

Figure 7 Monthly average flows for the Ord River, downstream of the Argyle Dam and the Dunham River confluence, 1974–2005. These data were used to calculate the Flow Stress Ranking for the Framework for the Assessment of River and Wetland Health ‘hydrological disturbance’ theme. Source: Dixon et al. (2011).

To obtain a catchment river health 1.8 A two-tiered approach to monitoring assessment, second-tier findings A major recommendation of the wet–dry tropical FARWH trial was a two- or scores can be extrapolated to tiered approach to monitoring (Dixon et al. 2011; Figure 8). The first tier the broader catchment based on monitors pressure on a catchment-wide scale. The second tier monitors knowledge of the relationships stressors and ecological response on a smaller scale to evaluate river health between the pressure, stressor of high management and conservation priority, including reference sites. This and ecological response themes. approach is similar to Queensland’s Stream and Estuaries Assessment Program This extrapolation would be based (SEAP), which uses a risk assessment to identify broad scale pressures, and on relationships between tier 1 then monitors stressors and ecological responses of the priority pressures pressures and tier 2 themes, and may (DERM 2011b). be quantitative or even qualitative. The latter qualitative approach was applied to the Daly River catchment (Dixon et al. 2011), which was classified into developed and undeveloped regions defined by the extent of sub- catchment native vegetation cleared. Quantitative approaches have not been researched in the wet-dry tropics. The recommendation for a two-tiered Catchment-wide Pressure Monitoring approach is an acknowledgment of (eg GIS and other spatial datasets) the mismatch between catchment Tier 1 Tier Fire regime Vegetation cleared Water extraction size and the resources available for river health monitoring, and the Small-scale Pressure/Stressor/Response Monitoring need for the efficient expenditure of (data collection for locally relevant indicators) monitoring budgets. It acknowledges Region 1: Region 2: Region 3: that not everything can be monitored everywhere. Tier 2 Tier Mine discharge licences Agricultural land use Stocking rates Tier 1 is envisaged to use mainly GIS Water quality Water quality Water quality or spatially explicit catchment-wide Macroinverterbrates Macroinverterbrates Streamside vegetation datasets. The tropical FARWH applied Fishes Fishes Turtles land-use and satellite-derived fire data (Figure 9), but could include the Figure 8 Two-tiered approach to river health monitoring (GIS). area of native vegetation cleared as a Source: Northern Territory Department of Land Resource Management surrogate for catchment development.

Monitoring river health in the wet–dry tropics 9 Tier 1 could also include the hydrology theme when hydrographic data are available. However, we caution against the use of Tier 1 monitoring for the fringing zone theme based on the proportion and area of cleared vegetation because most of the zone’s vegetation has not been cleared and would be better assessed on below canopy criteria, though this has practical constraints. Petty Tier 2 comprises small-scale, case

study–type monitoring to assess the Aaron

impact of a pressure on the ecological

condition of a river or stream. This tier Photos: could include an experimental design such as the before–after control- impact (BACI) or sites representing a

gradient of anthropogenic pressure. Legend An example of a well designed, 2008 Fire scar detailed study to elucidate the response of river health indicators to catchment pressures is provided by Arthington et al. (2007) for the wet tropics. The resources for monitoring could be assigned according to an explicit assessment of the risk of river health degradation, based on tier 1 data and an understanding of the relationships between pressure and river health. Point-source impacts on river N health are often monitored through 0 25 50 100 Kms government-licensed discharges and could contribute to tier 2 monitoring. Reference sites need to be monitored as part of tier 2 monitoring. Legend

Where resources and skills are 2006 Burnt river corridor severely limited, the most efficient and informative monitoring may comprise only tier 1 monitoring at a sub-catchment scale, and rely on the knowledge that reduced pressure will reduce degradation of river health. For example, resources may be better allocated to monitoring pig populations (pressure indicator) and their response to eradication measures, rather than monitoring a single stressor (eg pig physical disturbance along river reaches) or N the aquatic biota. 0 25 50 100 Kms The wet-dry tropical FARWH recommendation for a two-tiered Figure 9 Fires are now more frequent and intense in the wet–dry tropics (top). Catchment (middle) and river corridor (500 m widths; bottom) fire scars identified by the moderate-resolution imaging approach to monitoring concur in spectroradiometer (MODIS) for the Fitzroy River catchment (2008). Source: Dixon et al. (2011). principle with the recommendations for the national FARWH implementation (NWC 2011), although the latter includes the fringing zone and hydrological stressors as tier 1 components.

10 Monitoring river health in the wet–dry tropics period are reflected in the decreasing between-site dissimilarity (Figure 10). 1.9 Temporal High similarity in community structure (or low paired-site dissimilarity) is variability also evident at initial pool creation associated with early wet-season pool formation as a result of low diversity (Figure 11b) and common substrate- Temporal variability is important derived microcrustacean fauna. and needs to be considered when designing monitoring programs for The relevance of changing similarity in indicator assemblages over the annual river health in the wet–dry tropics. hydrograph for monitoring is that stream health assessments are based on Natural changes in ecosystems the comparison of community structures at the time of sampling at test associated with high seasonal and sites with those from a reference condition (reference sites are sampled interannual variability in climate simultaneously and/or are compared to baseline data). If annual monitoring and river flow can confound the is not standardised to the same or similar hydrological conditions, natural interpretation of monitoring results shifts in community structure among sites may be incorrectly attributed to if these changes are not well human-related disturbance, which may seriously confound monitoring results. understood. If standardisation of annual sampling times is not possible or if monitoring requires regular sampling during different seasons, then a full understanding Seasonal variability of ecological/community dynamics that govern inter-site community Researchers have investigated similarity for all relevant stream assemblages, not just macroinvertebrates, is the responses of stream essential. Flow or flow-related variables that are closely related to community macroinvertebrate communities dissimilarities may then be modelled to account for natural temporal during different phases of the variability using statistical covariance methods. This would then enable hydrograph in wet-dry tropical, the use of variants of classical hypothesis testing for impact detection and seasonally flowing streams, notably assessment (eg statistical tests of data gathered using BACI designs). within Kakadu National Park (Garcia et al. 2011; Humphrey & Douglas, unpublished data). An aspect of seasonal changes in community Stream structure was demonstrated by hydrograph calculating dissimilarity indices for the communities resident at two different sites in the same stream. These dissimilarity values are plotted bed Dry stream Discharge (cumecs) Discharge over the hydrograph conceptually in Figure 10. Periods in the hydrograph Marcoinvertebrate where paired site (upstream– community response downstream) dissimilarity are low indicate that the communities are relatively similar to one another in the types of taxa and relative abundances of taxa. Periods of ‘high’ dissimilarity, shown Paired site dissimilarity Paired in Figure 10, indicate either (a) Pre-flow, Wet season Recessional Post-flow, moderate and consistent flow or pool flow flow pool formation spate-related disturbance for periods formation and drying of flow connectivity (wet season); or Period of hydrograph (b) stochastic colonisation and other processes (eg different fish predation) Figure 10 Behaviour of paired-site (upstream–downstream) Bray–Curtis dissimilarity measures for occurring independently in pre-flow different phases of the hydrograph in northern seasonally flowing streams that cease to flow during the and late dry season pools. During latter part of the dry season. Source: Humphrey & Douglas (unpublished data). recessional flow as major flows The observations of increasing abundance and diversity of macroinvertebrates recede, disturbance effects dissipate in a section of stream of permanent flow, as shown in Figure 11(c), are relevant and habitat between adjacent sites to riffle habitat. These stream sections are effectively scoured during the tends to become similar. In response, wet season then become increasingly colonised by taxa with a preference diversity and abundances (number of for flow as the dry season progresses (Dostine & Humphrey 2011). In similar taxa per sample) increase (Figure 11), streams, Leigh (2011) examined seasonal (early and late dry season) patterns of and community structure becomes macroinvertebrate community structure in edge and sand habitats. For edge increasingly similar between paired habitat, converse patterns were observed to those from riffle habitat. Thus, as sites. These changes towards recessional flow declines to become undetectable in the late dry season and increasing similarity in community even cease, macroinvertebrate communities in both habitats tend to become structure over the recessional flow less diverse at the family level, with fewer taxa that prefer flow.

Monitoring river health in the wet–dry tropics 11 Interannual variability Garcia et al. (2011) have described 2500 50 interannual variation in the composition of invertebrate communities. This description was a 2000 40 summary of Humphrey et al. (2000), who examined and analysed long- 1500 30 term datasets from across Australia,

including three from streams in the 1000 20 Richness wet–dry tropics, to determine the Abundance degree of interannual variability 500 10 evident in stream macroinvertebrate communities. Indices were derived to (a) quantify persistence or constancy— 0 0 that is, the tendency for community O N D J F M A M J J A composition (presence/absence) or 2500 50 structure (relative abundance) to remain relatively unchanged between 2000 40 years. Using community structure data, persistence in Australian 1500 30 streams was generally found to be low. For wet-dry tropical Australia,

1000 20 Richness

Dostine and Humphrey (2011) showed Abundance how a gradual reduction in the base (dry season) flow of a perennially 500 10 flowing section of a stream, during (b) several consecutive years of below- 0 0 average rainfall, could lead to a O N D J F M A M J J A sudden switch from high abundances of flow-dependent taxa to the near 2500 50 extinction of several of these taxa. This switch persisted well after the years of low flow and when rainfall 2000 40 and flow had returned to average or above average conditions. 1500 30

1000 20 Richness Abundance

500 10 (c) 0 0 O N D J F M A M J J A

Abundance Richness

Figure 11 Seasonal patterns of stream macroinvertebrate richness and abundance for (a) a seasonally flowing stream with the hyporheic zone contact; (b) a seasonally flowing stream without hyporheic zone contact; and (c) a permanently flowing stream. Source: Garcia et al. (2011; Figure 5.2).

12 Monitoring river health in the wet–dry tropics Using community compositional • Although no significant correlations The Humphrey et al. (2000) research (presence/absence) data, several were observed between persistence was commissioned under the observations were made (Humphrey and latitude, there was a tendency National River Health Program to et al. 2000): for macroinvertebrate communities assess the implications of temporal • As interannual flow variation of permanent streams in temperate variability on the development of (as measured by the coefficient Australia to be more persistent AusRivAS predictive (bioassessment) of variation for annual flow) than those in permanent streams models. In particular, an important decreases, persistence in in tropical regions. The shorter life assumption of predictive modelling macroinvertebrate community cycles of tropical invertebrates (due is that macroinvertebrate community composition increases. Since to warmer water temperatures composition is reasonably constant interannual variation in flow for and because short cycles are over time. Despite the temporal most streams in the wet–dry selected for in regions with high variability found in the composition tropics is among the lowest seasonal extremes in discharge) of macroinvertebrate communities observed in Australia, this indicates were thought to contribute in streams of the wet–dry tropics, the that compositional persistence of to the reduced persistence of level of variability was considered macroinvertebrate communities in communities in permanent low enough for successful model this region is relatively high. streams of the Australian tropics. development. • Persistence was higher in streams • Cyclonic disturbance, and extreme (or portions of streams) of flood and drought were the main permanent flow than in streams factors causing low persistence of of seasonal flow that dry out for macroinvertebrate communities in a portion of the year. Stochastic Australian streams. Although none processes associated with of the wet–dry tropical streams macroinvertebrate recolonisation represented in the analysis by of seasonally flowing streams Humphrey et al. (2000) had been were presumed to explain the subjected to these (extreme) events greater interannual variability in for the record of data analysis, community composition observed cyclonic disturbance and floods in these streams. are features of the hydrological record of many of these streams and interannual shifts in macroinvertebrate composition can be expected to occur as a consequence.

Monitoring river health in the wet–dry tropics 13 Indicators The following section draws upon research conducted by TRaCK, as well as conclusions from several years of research and monitoring by TRaCK partners. It is not intended to be a review of all possible indicators for rivers and streams in the wet-dry tropics. benthic algae, is most likely to be The effect of discharge on river 2.1 River metabolism limited by nutrients (Ganf and Rea metabolism was investigated using 2007, Townsend et al. 2008, Robson time series analysis in the regulated Richard Hunt, consultant, et al. 2010). Thus, photosynthesis Barron River, which experiences and Simon Townsend, is responsive to primary producer high variation of depth and velocity Charles Darwin University biomass, and indirectly responsive during the dry season as a result to nutrient concentrations and of water released from a large in- River metabolism refers collectively trophic state. Nutrient pollution stream impoundment. Variation of to gross primary production and by nitrogen and phosphorus of GPP was predominantly explained ecosystem respiration in rivers (Odum the Daly River would be expected by discharge (~60%) while turbidity 1956), and underpins the trophic to increase primary producer and radiation were also explanatory structure and biomass of aquatic biomass and produce higher rates factors (~20% combined). ER was ecosystems. River metabolism of photosynthesis. Respiration in regulated by a combination of has been identified as one of five the Daly River is closely coupled to temperature and flow (adjusted fundamental ecosystem processes photosynthesis, and is potentially r2 = 0.57) and the river, which was (Giller et al. 2004). When calculated responsive to other anthropogenic consistently heterotrophic, shifted from diurnal measurements of impacts and nutrient pollution (see towards lower primary production to dissolved oxygen concentrations Young et al. 2008). ecosystem respiration (PP/ER) ratio and temperature, gross primary In the Mitchell River, water resource during periods of higher discharge production (GPP) and respiration (Hunt and Menke, unpublished data). refer to the total amount of carbon development is restricted to small fixed by photosynthesis and the areas in the upper catchment. A Nutrients can have a strong oxidation of organic carbon by natural flow regime persists through regulatory effect on the accumulation molecular oxygen, respectively. most of the river system. During the of primary producer biomass, River metabolism responds to a dry season high light availability, particularly when other controlling wide range of stressors that include clear water and stable perennial base factors such as light are not limiting. nutrient, chemical, and sediment flows can potentially support high River metabolism in a constructed pollution; flow alteration; the levels of aquatic primary production. wetland (Hunt, unpublished data) condition of the riparian vegetation; During wet season flows and floods, which received high nitrogen and channelization; and aquatic plant inputs of terrestrially derived organic phosphorus inputs from agricultural management (Young et al. 2008). matter can later drive high rates of runoff and aquaculture effluent Metabolism can be measured respiration in the river channel during was strongly autotrophic (PP/ using benthic chambers or the the dry season. Despite the low ER = 1.6) and contrasted with the open-channel method (Bott 1996). nutrient availability, gross primary normally heterotrophic status in Benthic-chamber measurements production was predominantly the river systems. Within the inlet are habitat or substratum specific, regulated by light and increased channel to the wetland, where the whereas the open-channel method lower in the catchment. The river water surface area and residency integrates metabolism over a river was heterotrophic and ecosystem times for suspended algae were reach and takes into account larger respiration (ER) was regulated by greatly reduced, respiration was very scale and spatially variable processes. temperature but was markedly high and the system was strongly Open-channel river metabolism was higher at the strongly heterotrophic heterotrophic (PP/ER = 0.25). investigated in the middle reaches downstream reach, suggesting that The advantage of open channel river of the Daly River over the dry season a greater quantity and quality of metabolism measurements, over (Webster et al. 2005, Robson et al. organic material accumulated lower the direct measurement of primary 2010, Townsend et al. 2011), and in the catchment (Hunt et al. 2012). producer biomass, is its considerably contrasting tropical freshwater greater efficiency of field, sample systems in Far North Queensland analytical and calculation effort. (Hunt et al. 2012). A comprehensive survey of plant Rates of photosynthesis and biomass for a 5 km reach could take respiration in the Daly River and three four to five days, and needs to be high-order tributaries were similar followed by sample preparation and between sites, and approximately laboratory analysis. In contrast, river doubled over the dry season. metabolism is determined from In the clear waters of the Daly River, dissolved oxygen and temperature primary producer biomass, notably data logged by a water quality probe deployed for several days, and also provides information about respiration processes.

Monitoring river health in the wet–dry tropics 15 Limitations and constraints to river Benthic algae also respond to metabolism monitoring, however, 2.2 Phytoplankton nutrient pollution, however, this include the need for a water quality and benthic algae depends on the current speed. In the probe that can log data, and use of Daly River, a field experiment showed an appropriate algorithm that best Simon Townsend, that the response of benthic algal estimates the oxygen reaeration Charles Darwin University biomass on pavers increased linearly coefficient. Also, the method is only with current speed (Townsend et al.). applicable to homogenous reaches Phytoplankton (microscopic algae) When nutrients were added, more of rivers and streams, without suspended in a river generally algae grew (relative to a control) in significant groundwater inflow originate from the riverbed or grow the faster currents than slower ones. over the study reach. Where a reach within the water column (pelagic), This implies the response of benthic includes large pools, relative to although a small number of algal algae to nutrient pollution will not runs, the method cannot be readily species are capable of growth in be uniform. Alterations to current applied because the diurnal oxygen both environments. The biomass of speed through river regulation and curve is not solely a function of pelagic phytoplankton in fast-flowing flow modification will also have photosynthesis and respiration, but rivers is commonly constrained implications for current-mediated confounded by pool hydrodynamics, by the continual advective losses nutrient uptake by benthic algae and which can result in diurnal curves downstream. Otherwise, light and by inference algal biomass (Townsend with a night-time dissolved oxygen nutrients limit phytoplankton and Padovan 2009). The spatial and concentration maxima (Dixon et al. biomass, sometimes interacting with temporal variability of benthic algae 2011). river bathymetry and flow. may be high (eg Townsend and The application of river metabolism in Padovan 2005) and require too many The composition and growth of resources to be a resource-efficient unimpacted systems can be used as a phytoplankton has been investigated baseline measure of the fundamental indicator, unless these factors can in the Daly River (Townsend et al. be standardised and undertaken processes that support river 2012). Most phytoplankton were ecosystems and provide a comparison on a small scale. Monitoring river pelagic, with a single species metabolism is an alternative. to systems affected by disturbance. dominant. Loads of chlorophyll a Photosynthesis and respiration are biomass, and sometimes the responsive to stressors and indirectly dominant alga, increased to catchment pressures. The rapid downstream, suggesting net biomass response of river metabolism to growth. Overall, the biomass of stressors, which can be measured pelagic phytoplankton species was at a daily time scale, provides a most likely to be limited by nutrients, powerful indicator of river function rather than advection, except possibly changes over short time frames and along specific reaches. longer periods. By quantifying the response of metabolism to variation Consequently, phytoplankton of light, nutrients, temperature and concentrations in the Daly River are discharge, time series models can likely to be responsive to nutrient be used to estimate how different pollution. When using phytoplankton environmental stressors affect to monitor an ecological response to these regulatory factors, and to nutrient pollution, chlorophyll a predict their impact on ecosystem concentrations are a simple functioning. indicator of phytoplankton biomass, but should be accompanied by the enumeration and biomass computation of phytoplankton species to assess the domination of pelagic species over riverbed species.

16 Monitoring river health in the wet–dry tropics The traditional method for this 2.3 Water quality assessment is to measure nutrient 2.4 Freshwater fish concentrations in the water, and use Michele Burford, Australian Rivers Mark Kennard, Australian Rivers both the concentrations and ratio Institute, Griffith University Institute, Griffith University of nutrients to assess whether the waterbody is likely to be limited by Evaporation drives the water quality nitrogen or phosphorus, or both. Fish are widely advocated as useful of waterholes However, it is difficult to assess indicators of ecosystem health (eg Many rivers in the wet–dry tropics when nutrient concentrations are Fausch et al. 1990, Harris 1995, Karr cease flowing during the extended limiting to growth, as other factors and Chu 1999), because: dry season to become a series of can limit growth such as the rate that • they are almost ubiquitous disconnected waterholes. This nutrients are being cycled, the growth components of aquatic ecosystems includes the Flinders River system rate and physiological state of the • they are relatively long-lived and in the southern Gulf of Carpentaria phytoplankton, and the contribution mobile, and therefore reflect (Queensland). These waterholes of other limiting factors such as conditions over broad spatial and persist throughout the dry season, light. Therefore, a complementary temporal scales providing refuges for plants and method of assessment is to conduct animals. Studies of the Flinders phytoplankton bioassays. This • local assemblages generally include River system have shown that water involves adding nitrogen, phosphorus, a range of fish species representing quality in these waterholes changes and nitrogen + phosphorus to water a variety of trophic levels and over the dry season, with parameters samples, incubating them for a set therefore integrate effects from such as nutrients and chlorophyll a period with sufficient light, then lower trophic levels increasing in concentration due measuring growth, photosynthesis or • fish are at the top of the aquatic to evaporative concentration biomass accumulation. By comparing food web (with the exclusion of (Faggotter et al. 2010). Water quality these treatments with a control, crocodiles) and are consumed by is dependent on the initial dry season with no nutrient added, it is possible humans, making them important quality, rate of evaporation and to assess whether phytoplankton for assessing contamination waterhole average depth. Turbidity respond to nutrient addition, and • environmental and life history due to clays and other colloidal to which nutrients. Knowledge of requirements are comparatively material which remain suspended the limiting nutrient(s) will help well understood can also increase over the dry direct management to reduce season due to waterhole evaporative nutrient enrichment, as nitrogen and • they are relatively easy to collect, concentration, as shown by Townsend phosphorus differ in their behaviour identify and subsequently release (2002). The effect of evaporative in the environment. unharmed. concentration on water quality is The documented responses of fish inversely related to the average depth Bioassays conducted in the to a diverse range of anthropogenic of a water hole, and needs to be waterholes of the Flinders River disturbances suggest that fish may taken into account when interpreting system in the southern Gulf of be sensitive indicators of the net water quality monitoring data. Carpentaria, and the middle reaches of the Daly River have shown that effect of human impacts on aquatic Nutrient bioassays phytoplankton were limited by ecosystems. Fish also provide an Four key factors typically both nitrogen and phosphorus easily interpretable endpoint of affect phytoplankton growth: (Faggotter et al. 2010, Robson et al. environmental degradation and can hydrodynamics, light, grazers and 2010). This suggests that managing be used as a justification for remedial nutrients. The macronutrients phytoplankton bloom issues requires action, given their ecological, social nitrogen and phosphorus are controlling inputs of both these and economic importance. essential for phytoplankton nutrients. Fish can be used as indicators of growth, but in excess can result ecosystem health by assessing in blooms and reduce ecosystem toxicant bioaccumulation, fish health. Therefore, understanding condition and incidence of fish the role of nutrients in promoting kills, trends in recreational or phytoplankton growth is a critical commercial fish catches; or by using component to understanding the summary indicators describing fish effect of anthropogenic and climatic assemblage structure and function, impacts. and comparison with least disturbed (reference) conditions. There are, however, a number of challenges with the use of fish as indicators, including:

Monitoring river health in the wet–dry tropics 17 • the difficulty in separating natural A systematic evaluation of these versus disturbance-induced key requirements has recently 2.5 Macroinvertebrates variation (which requires an been undertaken for the Daly River Chris Humphrey, Environmental accurate definition of the expected catchment (see Dixon et al. 2010) Research Institute of the or reference condition) using data collected from past TRaCK Supervising Scientist, Australian research (Chan et al. 2011, Stewart- • responses to anthropogenic Government Department of Koster et al. 2011) and new data from disturbance are not well Sustainability, Environment, Water, a large number of sites subject to established or validated Population and Communities varying intensities of disturbance • the possibility of poor diagnostic due primarily to cattle grazing, feral potential, because fish are likely to animal activity and the associated Stream macroinvertebrates remain reflect the result of an integrated local riparian, in-stream habitat and the most logical and popular choice effect of a range of disturbance water quality degradation. for monitoring of stream health sources (except for extreme or in Australia, including the wet–dry obvious disturbances, such as The study revealed that fish tropics, because of their inherent toxicants or barriers to migration), assemblages sampled by virtues and adoption under National due to relatively high mobility and electrofishing with at least 10 five- River Health Initiatives as the flagship longevity. minute electrofishing ‘shots’ provided indicator group for this purpose accurate and precise estimates of (see ANZECC-ARMCANZ 2000). As The central goal of bioassessment is local fish assemblage attributes with a consequence, national protocols to decide whether a site exposed to a high degree of statistical power to have been developed (ie the AusRivAS anthropogenic stress is impaired while discriminate between sites. predictive modelling approach minimising type I errors (incorrectly to stream health assessments), classifying a site as impaired) and A set of candidate ecosystem health underpinned by substantial research type II errors (incorrectly classifying a indicators was selected based and the development of a significant site as unimpaired). The development on fish assemblage composition, skill base across Australia. By of a fish-based monitoring species’ relative abundances and comparison, the limited expertise program should satisfy several key ecological trait composition (fish in Australia in phytoplankton, and requirements before it can be applied species morphology, habitat use, especially zooplankton, biology has for ecosystem health assessment in a reproduction, movement and trophic placed severe constraints on the given river or region (Kennard 2005). requirements). Evaluation of natural general utility of these groups for These requirements include (but are variation in these fish assemblage routine stream health assessments. not limited to): attributes in response to natural environmental gradients (using Macroinvertebrates are used in • the ability to collect raw biological predictive models developed and monitoring programs for biodiversity data in a standardised fashion validated using a set of minimally assessments (see ANZECC-ARMCANZ and with sufficient accuracy disturbed reference sites) revealed 2000), with the measured responses and precision such that it truly that the reference condition could being regarded as surrogates represents the locality in question be reliably defined for only fish of ecosystem-level change. and is directly comparable with assemblage composition. The Macroinvertebrates may be used to other locations results of the study also indicated assess broad-scale land use changes • assessment of the natural ranges that disturbed streams and rivers or disturbances associated with in spatial and temporal variation in the Daly River catchment were point-source disturbances. of the biological attributes in likely to display some differences in The first attempt at a synthesis of question, and the drivers of this native fish assemblage composition information on macroinvertebrate variation from that expected by comparison with similar areas not subject to communities from wetlands and • the ability to accurately define the disturbance (using the predictive waterways within Australia’s wet–dry reference condition for biological model). Deviations in fish assemblage tropics was undertaken by Humphrey attributes expected in the absence composition from expected natural et al. (2008) as a component of of anthropogenic stress based on conditions can therefore potentially the Tropical Rivers Inventory and relationships between natural be used as summary indicators of Assessment Project (TRIAP; Finlayson environmental drivers and biotic degraded ecosystem health and be and Lukacs 2008). For this, the team patterns, such that human used for identifying areas that may examined two aspects: disturbance-induced changes can require management intervention. • broad-scale river health be quantified using biological However, their utility in diagnosing assessments: an analysis of indicators sources of disturbance or the AusRivAS family-level data from • the sensitivity and demonstrated mechanisms by which they influence wet–dry tropical Australia (Western ability of the chosen indicators fish is debatable and requires further Australia, Northern Territory and to reflect or respond to human examination. Queensland datasets) disturbance.

18 Monitoring river health in the wet–dry tropics • macroinvertebrate inventory Some association between including low dissolved oxygen records for assessments at specific macroinvertebrate communities and regimes, and aerial breathing forms sites and/or for conservation and water quality (namely, conductivity) are well represented. The stream biodiversity importance. was also evident in Kimberley faunas present in upland sites with For the first component, AusRivAS streams, but these relationships rocky substrates include many bioassessment data were assessed in were rather weak and are consistent flow-dependent taxa, and a number two ways for TRIAP: with past analyses (Kay et al. of these forms have proven to be 1999), suggesting a lack of major sensitive to water quality and flow • evaluating the potential to derive geographic and climatic barriers variations (eg the mayfly family, wet–dry tropical AusRivAS models, that would otherwise promote such Leptophlebiidae). with possible improved precision zoogeographical separation. and resolution, with the artifices It is a common observation that, by of jurisdictional boundaries For the second study component recessional flow periods in the early removed as current models had listed above, the task of extracting dry season (and in the absence of been developed for each state and and compiling macroinvertebrate acid mine drainage and persistent territory, or regions therein species-level data from northern salinity issues), fauna have recovered Australian streams was impractical. from wet season disturbance • seeking links between Instead, extensive consultation events (natural or anthropogenic), macroinvertebrate data and was used to compile metadata most likely reflecting the short life corresponding environmental descriptions of the macroinvertebrate cycles of most northern species, data, including hydrology, habitat, species-level data available for the high vagility of many species, geomorphic classification and sourcing and compiling, should this and the generally intact landscapes water quality datasets of the need to be identified, prioritised and of the north such that potential respective stream sites. adequately resourced. A number of recolonisation sources are relatively In relation to the potential to derive government agency staff and other plentiful and never too far away. unified wet–dry tropical AusRivAS specialists contributed to this task. Stream health assessments using models, the analysis of Humphrey These metadata descriptions are macroinvertebrate community data et al. (2008) was not particularly contained in Humphrey et al. (2008). in tropical Australia may be better encouraging. The combined Western Compilation of these metadata informed through an improved Australia, Northern Territory and highlighted the need for further work understanding of distributions, Queensland datasets showed a on inventory and taxonomy, but also life histories and habitat profiles separation in multivariate ordination database management to allow for of resident species. Research, data space that was consistent with cross-regional comparisons. compilations and reviews could prove differences in sample processing Other synthesis and review studies invaluable in the following areas: methods adopted by the different for macroinvertebrates of wet–dry • an improved understanding of the state and territory agencies. tropical streams of northern Thus, any identified separation of functional feeding group categories Australia were conducted by for northern species macroinvertebrate communities Finlayson et al. (2006) and Garcia based upon environmental variables et al. (2011). Seasonal and inter- • habitat profiles of resident species could be confounded by artefacts annual variability of wet–dry tropical (distributions, environmental introduced in sample processing stream macroinvertebrates are also requirements - see Suter et al. 2006) methodology. described in Section 1.9 of this report. • the potential to use species traits of Relationships were sought between Some general comments about the life history, dispersion, reproduction macroinvertebrate data and role and utility of macroinvertebrate and general physiology to provide corresponding environmental data communities for monitoring and greater resolution in stream for Western Australia, Northern assessing the health of seasonal and health assessments (compared Territory and Queensland AusRivAS temporary waterbodies in the wet– with conventional taxonomic datasets. Distinct zoogeographic dry tropics remain. The experience of approaches) separation of macroinvertebrate researchers and government agency • the potential for development communities was evident within staff suggests that there is a general of biotic indices for northern northern Western Australia and resilience of macroinvertebrate streams (eg northern SIGNAL - see within Queensland to distinguish communities in these systems. Chessman et al. 1997) gulf-flowing streams from inland- The life cycles of species in stream • the synthesis and management of flowing streams. At a smaller scale, systems that dry out are adapted to databases for species distributions within the Daly River catchment, seasonal drying and the species are (eg Australian Biological Resources a distinct biological pattern was typically cosmopolitan, vagile and/ Study Fauna Online, Australian revealed and found to be associated or include seasonal dormancy in National Insect Collection mainly with stream water chemistry their life histories. Those that persist Database, Australian Natural and local hydrological conditions. in pools by the late dry season are Heritage Assessment Tool). quite tolerant of poor water quality,

Monitoring river health in the wet–dry tropics 19 the number of cow pats counted 2.6 Ecogenomics 2.7 Time-lapse on transects (Figure 13). The photos showed that, as the dry season Chris Humphrey, Environmental photography progressed and water became less Research Institute of the available on the landscape, the Supervising Scientist, Australian Tim Jardine and Jeff Shellberg, frequency of visitation to these Government Department of Australian Rivers Institute, permanent waterholes by cattle Sustainability, Environment, Water, Griffith University increased. Shallow waterholes with Population and Communities The remoteness of the northern high cattle activity had high nutrient concentrations and turbidity at the The field of genomics is a new Australian landscape and the strong hydrologic seasonality restrict year- end of the dry season, while deeper area of biological assessment. It waterholes visited less often by cattle offers potentially cost-effective round access to many important river and wetland sites. Time-lapse had lower nutrient concentrations identification of all organisms, and less turbid water. including microorganisms and photography offers the potential to meiofauna, within biological overcome some of these limitations Photos from time-lapse cameras also assemblages through techniques by providing information at hourly or provided the necessary resolution that target a single or multiple daily intervals throughout seasons to estimate the cover of aquatic gene(s) of interest that are present when access is difficult or impossible. plants and observe many of the in all organisms of interest in the Two examples of the utility of time- dominant species present, including sample (ecogenomics). The field of lapse cameras are provided below: weeds (eg water hyacinth). Per cent functional genomics uses analyses one is for identifying animal pressure cover estimated from the photos of an organism’s ribonucleic acid on waterholes and subsequent by a viewer with no knowledge of (RNA) to identify changes in gene ecological response (Figure 12), and the sites (an overseas colleague) expression, thereby providing the other is for measuring gully was highly correlated with transect information on the mode of action of erosion retreat rates and hydrological measurements, and independent contaminants or other environmental processes (Figure 13). measurements using the photos by stressors on individual organisms Example 1: Waterhole animal use two of the project team members (contaminant-specific biomarkers of and ecological response were also highly correlated. From this, exposure and effects). Ecogenomics Animal pressures on waterholes the seasonal changes in aquatic plant will potentially overcome the (feral pigs, cattle) and the ecological cover could be estimated throughout major limitations of assemblage response (aquatic plant cover) to wet periods when the sites were group assessments, including seasonal changes and pressures inaccessible. They showed that cover phytoplankton, zooplankton and were identified using time-lapse typically declines towards the end other microorganisms referred cameras (Moultrie Gamespy, EBSCO of the dry season, followed by rapid to above (ie taxonomic specialist Industries Inc, Alabaster, 2848 x 2136 regrowth after the first flood event shortages). While this area of pixels, ~6 MP) that were mounted on of the wet season. This highlights biological assessment has not trees at nine permanent floodplain the need to consider seasonal been studied as part of TRaCK, it waterholes in the lower Mitchell dynamics in the assessment of river is incorporated in the National River, Queensland. At three of the or waterhole condition. Environmental Research Program, sites, both time-lapse and motion- For animal assessments, the and future investigative studies will detect cameras were installed to major limitation of the time-lapse be conducted in the Alligator Rivers compare the relative merits of the cameras was that they considerably Region on this topic. two types. Along with a series of underestimated pig activity. High- other measurements not described intensity, nocturnal pig intrusions here, transects into the riparian to waterholes that were short in zone and the waterhole were used duration were often captured by to assess cattle activity and aquatic motion-detect cameras, but these plant cover and compared with animals were rarely captured by information obtained from the time-lapse cameras. This can be cameras. addressed by reducing the frequency Time-lapse cameras were superior of image collection from hourly to to motion-detect cameras because daily (depending on the goals of they provided standardised measures the monitoring). However, extra of pressure on waterholes (cattle battery capacity is required to collect presence). The total number of cattle hourly images over many months. photographed at a site was strongly correlated with a secondary measure of cattle activity:

20 Monitoring river health in the wet–dry tropics Jardine

T

Photos:

Figure 12 Time-lapse photographs of (top) cattle and pig visitation, and (bottom) a dry season waterhole, later covered by aquatic plants in the wet season.

Another limitation of time-lapse cameras in general is the difficulty of maintaining the cameras in the harsh conditions encountered in northern 100 Australia (rainfall, humidity, heat and ultraviolet light exposure). This can be partially overcome by sealing 80 joints on the outer surface of the camera and adding protective covers, 60 as discussed below. Time-lapse cameras offer the 40 potential to assess the positive and negative impacts of cattle on waterholes (Jansen and Robertson 20

2001, Marty 2005), as well as seasonal on transects counted pats Cow changes in plant cover and weeds, 0 and to do so at times of the year 10 100 1000 10000 when access to sites is otherwise impossible (see Figure 12). Cattle captured by camera

Figure 13 Correlation (r=0.89, p=0.007) between cattle photographed and cow pats counted on transects.

Monitoring river health in the wet–dry tropics 21 Example 2: Gully erosion retreat rates Observed water sources for erosion watertight seal. Future deployments and hydrological processes came from the combination of direct could use improved weatherproof Gully erosion retreat rates were rainfall, diffuse infiltration-excess housings, however this will increase measured using time-lapse cameras water dripping over the scarp face, costs relative to the price of the (Moultrie Gamespy, EBSCO Industries infiltration-excess runoff plunging cameras. Inc., Alabaster, AL, 2848 x 2136 pixels, off the scarp face, and backwater into The oblique time-lapse photography ~6 MP) that were mounted on stable and full inundation of the scarp face proved to be valuable for qualifying trees at three alluvial gully sites along from river floodwater. The 24-hour basic hydrogeomorphic processes in the Mitchell River Fluvial Megafan, rainfall total was the best predictor remote locations, and for quantifying Queensland (Shellberg et al. 2012). of daily scarp area change for all sites daily scarp retreat and relative Oblique daily photographs were (r2 > 0.60) and likely represents a planform area change in conjunction internally rectified to each other in a proxy measure for a whole suite of with annual GPS measurements. GIS using ground control points. The measured and unmeasured variables More intricate camera setups gully scarp edge was digitised daily influencing gully scarp retreat. The could be used in the future, such after intervals of observable change. incursion of river backwater and as vertical views (ie for towers or Due to the oblique angle, only a overbank flooding into alluvial gullies trees) or horizontal views of the relative change in gully area at the episodically overwhelmed typical gully face using multiple cameras. scarp edge could be measured, which rainfall-runoff processes and caused While oblique photographs from was calculated as the percentage major scarp retreat at frequently non-photogrammetric cameras are of daily change divided by the total inundated sites. not ideal due to potential sources of change over the period of record. To Several initial electrical corrosion quantitative error, they are extremely estimate actual planform change, the problems were encountered with cost effective and more practical than percentage of daily change divided the time-lapse cameras due to harsh obtaining low-altitude, large-scale by the total change was multiplied moisture conditions during the four- aerial photographs at the daily scale against the horizontal area change month wet season deployments. to measure scarp retreat. Overall, measured during annual GPS However, these problems were fixed time-lapse photography is a valuable surveys using a differential global by using silicone along every joint tool for managers and scientists for positioning system (GPS) (Trimble of the camera housing to ensure a short and long-term monitoring of with Omnistar HP; see Brooks et hydrogeomorphic and ecological al. 2009). These erosion index data processes. were then compared against daily rainfall metrics, river/gully water surface stages, and photographic observations of hydrological processes. Shellberg

J Daily time-lapse photography

demonstrated that annual scarp Photo: retreat was the cumulative sum of both subtle and major incremental failures of discrete soil blocks or smaller flakes (Figure 14), and was driven by multiple water sources and erosion mechanisms.

Figure 14 Incremental change in gully location from daily photographs at site KWGC2 between 2007 and 2010, Mitchell River Fluvial Megafan.

22 Monitoring river health in the wet–dry tropics Community monitoring The Department of Water Providing capacity building for 3.1 A Kimberley (Kununurra) and the University of waterway management from a case study Western Australia (TRaCK) jointly community, government agency and initiated the program, partnering research organisation perspective Rebecca Dobbs, Centre of with communities and Indigenous is an important step towards Excellence in Natural Resource rangers employed through the better management outcomes for Management, University of Working on Country (WOC) Program waterways in the Kimberley. The Western Australia to manage the cultural and WEP has led to the establishment environmental values of their land of a number of ongoing monitoring Natural resource management can and sea estates (eg weed control, fire programs, including those focused benefit from collaboration with local management, feral animal control). on issues of fish parasites and long- communities in research, monitoring, The Kimberly WEP focuses on term monitoring in Lake Gregory by identification of values and the strengthening local community Paruku Rangers (Dobbs et al. 2011a), development of management knowledge and participation in and monitoring of feral pig impacts procedures, priorities and strategies. natural resource management, by Wunngurr Rangers in the Willigan In particular, monitoring is an with an emphasis on providing area (Dobbs et al. 2011b). important process for evaluating remediation actions and monitoring Lessons from the Kimberley WEP the effectiveness of management techniques for rivers and wetlands. can be applied to other programs actions and a key component in any Delivery involves hands-on field and highlight how an education adaptive management framework. sampling of a range of indicators, program can assist with community In the Kimberley region of northern including macroinvertebrates monitoring through its ground- Western Australia, remoteness (‘bugs’), fish, water quality and up approach. Important features combined with limited resources and vegetation, providing an interactive contributing to the program’s success community capacity has the potential demonstration of western science include: to restrict onground management techniques and their application for • an appreciation for the value of and monitoring of rivers and their river monitoring (Figures 15 and 16). information exchange between catchments. This collaboration allows rangers western science and Indigenous To address these issues, a to combine up-to-date research knowledge waterways education program with their onground knowledge to • building on existing programs, (WEP) was developed and has identify issues of concern in their relationships and initiatives, which been implemented over the past management area. After initial reduces development costs and three years (Dobbs & Cossart training, the WEP offers further increases the time spent onground, 2010). The Kimberley WEP relies on training for targeted onground while also ensuring that with partnerships between government, monitoring and remediation, changes in funding opportunities, research and community groups supporting rangers to monitor the program maintains longevity involved in regional natural resource and ultimately manage their local management, with adequate regional waterways. capacity and community involvement considered a fundamental management requirement. Dobbs

R

Photos:

Figure 15 Monitoring by Kimberley Wuungurr Rangers (fish) and Paruku Rangers (water quality).

24 Monitoring river health in the wet–dry tropics • flexibility to allow participants A number of limitations and Secondary benefits highlight that to achieve different objectives, challenges from community the focus of community monitoring including language, mentorship monitoring in the tropics have been programs should not always be on and accreditation for TAFE courses overcome, although there are also providing scientific data to feed (also ensuring increased uptake issues yet to be addressed. To address into western science. The Kimberley and longevity of the program) data management issues, monitoring program has facilitated the • the provision of embedded programs have been adapted into development of new partnerships scientists and managers Cybertracker sequences for use on with a large number of stakeholders (facilitating community access to hand-held computers. TRaCK is also (including government and non- research and management – an currently working closely with the government agencies, land councils, important strategy in a large, North Australia Indigenous Land and language centres, Indigenous remote region). Sea Management Alliance (NAILSMA) Protected Areas and schools). to combine monitoring techniques By integrating a cross-agency The Kimberley WEP has adapted with new technology and build into program of water planning, research and trialled various monitoring the NAILSMA I-Tracker program, and management, the program techniques, tailoring them which will help standardise ranger provides an important vehicle for specifically to community and monitoring techniques used across participants to interact and be Indigenous ranger use in the tropics Dobbs

R

Photos:

Figure 16 Monitoring by Paruku Rangers using hand-held computers and Cybertracker software.

(Dobbs and Cossart 2010). These northern Australia. More work is involved in activities undertaken by methods include a modified version needed to develop and trial suitable researchers. Government agencies of the Tropical Rapid Appraisal of indicators that rangers can collect, involved in the WEP subsequently Riparian Condition (TRARC), which interpret and sample while also being employed ranger groups during is currently being trialled for its use sensitive to disturbances. TRaCK trials of the Framework for in assessing riparian vegetation and Despite these challenges, Assessment of River and Wetland weed impacts. Trials have also shown the WEP has helped communities Health (FARWH). that quantitative estimates are to increase their capacity to manage difficult to obtain with consistency, waterways and to strengthen and semi-quantitative methods their ownership of environmental (eg photo points and line-intercept issues, while also building methods) have been effective in researchers’ capacity to incorporate identifying feral animal, weed and Indigenous knowledge into projects. erosion impacts. These results support other TRaCK research trialling community monitoring techniques (Featherston et al. 2011a,b; Finn et al. 2011a,b).

Monitoring river health in the wet–dry tropics 25 3.2 Trial Indigenous participatory monitoring program

Emma Woodward, Tropical Ecosystems Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO)

Monitoring programs Researchers Marcus Finn and Pippa Featherston (CSIRO) from the TRaCK project ‘Indigenous socio-economic

values and river flows’ collaborated Featherston

P with Indigenous communities in

the Fitzroy (WA) and Daly River (NT) Photo: catchments to develop and trial a 12-month participatory monitoring Figure 17 Gooniyandi monitoring participants testing water quality. program for flow regime changes and wild resource use. A range of water quality Permanent photo points proved Four Aboriginal land management measurements were taken at a to be a quick, consistent and easy- groups participated in the trial number of sites. The use of water to-replicate way of collecting monitoring: the Wagiman- quality as an indicator reflected the information on water levels, aquatic Guwardagun Rangers and Malak groups’ perception that it was a and riparian vegetation changes Malak Rangers from the Daly River legitimate indicator of aquatic health (including weed growth), disturbance (NT), and the Gooniyandi Rangers from a western science perspective. by cattle and feral animals, and in and a family group from Parkul A manual water quality kit was some cases, the characteristics of Springs/Bidijul from the Fitzroy used, but limited training in the kit’s cultural sites. Although the results River (WA). The trials commenced use meant that it was difficult for of the permanent photo points were with each group identifying key groups to use without assistance not quantitative measurements, the sites for monitoring based on (Figure 17). More consistent results photos gave the Indigenous research perceived threats to values at these could be obtained by using a more participants the opportunity to view sites, suitable indicators to monitor automated water quality testing unit temporal changes at a single point in outcomes for water management that did not require in-field mixing of time. Obvious impacts that could be plans, and monitoring techniques chemical reagents. assessed included feral pig damage that each group wished to trial. Recording and measuring of fishing to billabongs (Figure 19). Permanent The monitoring methods were catches was tested by two of the four photo points were by far the most also selected for their ease of monitoring groups. This technique, accepted technique of recording implementation. The methods tested while popular, proved problematic information, and the easiest to included: due to the limited time available. implement. • establishment of permanent photo Fishing, and the subsequent Most of the groups did not have points and canopy cover photos measuring of catch, tended to be easy access to computers or the done on an opportunistic basis. relevant training required for data • measurement of water quality The use of transects for assessing storage, analysis, report writing and • catch rates and recording of fishing weeds and disturbance by cattle publication. This meant that future trips and feral animals (Figure 18) was participatory monitoring programs • using transects to assess landscape successful in some communities but should consider an individual group’s changes. not in others. The physical ability of a requirements for supervision, group determined the success of this support, and championing by an method. The technique was tested organisation with access to necessary and quickly discarded by one group, skills and equipment. whose rangers were quite senior and physically challenged by walking across rough terrain.

26 Monitoring river health in the wet–dry tropics Figure 18 (left) Ranger using a tape measure to assess the incidence of animal damage along a billabong edge.

Figure 19 (below) Extensive feral pig damage along the edge of a billabong (Daly River). Featherston

P

Photo: P Featherston

Photo: Photo: Malak Malak Land Management Rangers

A monitoring program that TRaCK Indigenous workshop • What are the top five water health involves Indigenous ranger groups Lessons learned through the TRaCK threats (in your management – whether these groups are funded participatory monitoring program area)? Highlight the top one or two or informal – should prioritise an were shared with Indigenous land threats. assessment of the groups’ capacity management groups at the NAILSMA • What part of the river system at the beginning of the monitoring I-Tracker Forum held at Mary River is your top threat affecting program. A successful monitoring Park (NT) in September 2011. A (eg billabong, main channel, program will need to ensure that specific session, the ‘TRaCK Water floodplain)? monitoring support and training is Forum’, was held to discuss water clearly identified and funded as part monitoring with participants and After these initial questions, of the program, particularly where to seek feedback about the groups’ individual groups were then asked the group identifies limitations in own concerns for water health and the following questions: their ability to engage in and carry management (Figure 20). • What are you monitoring now? out activities. The following questions were asked: What is in your management plan? • What you would like to monitor? Kimber

A

Photos:

Figure 20 Identification of common issues at the September 2011 workshop.

Monitoring river health in the wet–dry tropics 27 The common threats across the • The difficulties associated with • Issues relating to the validity of region were identified as being feral accessing advice on, and the compliance monitoring—there is a animals (several species), weeds provision of appropriate monitoring perception that it could be a waste (several species), sediment and equipment, and the ability to get of time. erosion (from different sources, it to remote areas. More technical • The lack of baseline information. including mining and from road support would address this. For example, how many megalitres development) and mining (which is • The difficulty of accessing Country flow out? How much sediment seen as an increasing threat). to monitor. should be in the river? Across all groups, many river • The lack of a framework of ‘issues’ • Opportunities for Indigenous and wetland habitats were across the north. For example, in employment have improved, but represented as being under threat. Cape York, the issues that require Indigenous people should not just Examples of threats and habitats monitoring should perhaps be be seen as a labour force; they need threatened for two of the regions identified first, before a dedicated to be partners in the research and are shown in Table 1. person(s) is appointed to provide in designing and understanding All Indigenous land and sea the training requirements. the monitoring programs. management groups that • The cost of sending samples away Further information about the trials participated in the workshop are ($3000–$4000 for more expensive can be obtained from Featherston et already undertaking some form of tests). Also, consultants are needed al. (2011a,b), Finn et al. (2011a,b) and monitoring on Country, but many, if to interpret results. Jackson et al. (2011). not all groups, are keen to strengthen this component of their management • The lack of a ‘one-stop shop’ plan. The group identified some and assistance with designing a impediments to undertaking current monitoring program. and future monitoring, and made the • The inability to detect change following commentary: because a lack of capacity may be setting up a false sense of security. • Inadequate Caring for our Country funding—every year, projects miss out.

Group/region Top threats ‘River’ habitats threatened by the top threats Cape York (Central East Coast River Pigs and cattle; tourism; mining; Wetlands, floodplains, estuaries, System) legislation; climate change; erosion catchments West Cape York (Napranum, Mining and groundwater quality; pigs Mining effects: waterholes Mapoon, Lockhart) and weeds (control measures and (construction); river mouth blocked environmental health); agricultural by sediments; seagrass and industry (sediment, chemical mangroves on estuaries and coast, pollution, run off); climate change; river channel (water take) water usage); groundwater quality Weeds: floodplains; creek channel (domestic use) and sea (pesticide and sediment control); estuarine and coastal systems Groundwater: domestic use, extra or added pressure on existing water systems through increased mining

Table 1 Threats identified by the September 2011 workshop participants.

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Monitoring river health in the wet–dry tropics 31 To find out more about TRaCK, visit www.track.org.au email [email protected] phone 08 8946 7444

TRaCK partners Australian Government Department GeoScience Australia of Sustainability, Environment, Water, Government of Western Australia Population and Communities Griffith University Australian Institute of Marine Science James Cook University Australian National University National Water Commission Charles Darwin University North Australia Indigenous Land CSIRO and Sea Management Alliance Environmental Research Institute Northern Territory Government of the Supervising Scientist Queensland Government Fisheries Research and Development Corporation University of Western Australia