Bardi Jawi Rangers turtle tagging expedition

By KLC
The Bardi Jawi Rangers have been tagging turtles with satellite transmitters to discover more about their genetics, life cycle, travel and feeding patterns.

During the four-day research expedition, data was collected from more than 30 green turtles within the One Arm Point area on the Dampier Peninsula.

CSIRO scientist Mat Vanderklift prepares to attach a satellite tag to Iwany the green turtle while children from the Bardi Jawi community watch.

Bardi Jawi Indigenous Protected Area coordinator Daniel Oades said the satellite project had been a collaborative effort involving researchers and scientists from CSIRO and DPaW and the Bardi Jawi Rangers.

He said flipper and satellite tags were used as a way to capture various data about the marine species.

Local schoolchildren release a green turtle after it has been weighed and measured by scientists and rangers

“The satellite tags use a saltwater switch, so that when the turtle comes to the surface for air it sends signal fixes to a satellite to record location,’’ Daniel said.

“Another satellite tag focuses on transmitting depth and dive profile data. This is important because we don’t understand what turtles are doing for the majority or their life cycle, where they are going and where they are feeding.

“Bardi Jawi is not a high density nesting area for turtles but more of a foraging ground, so tagging turtles here will provide us with information about what turtles are coming past, what they are using Bardi Jawi country for, where they are coming from, whether it’s from Indonesia or the north-west shelf genetic stock of Australia.’’

The rangers collected the turtles and brought them to the ranger vessel Almban where they were measured and weighed and had their general health recorded. Skin and blood samples were collected for genetic testing and all the turtles were fitted with flipper tags.

“The rangers used their traditional knowledge to find the best place to locate and capture the turtles. Through being involved in satellite tagging, we get to improve on our marine science and research skills and test out our ranger vessel as a working platform,’’ Daniel said.

“We had the Bardi Jawi Oorany (Women) Rangers and about a dozen school children join in. Many of the young kids hadn’t done this sort of thing before, so it was also a good opportunity to teach our young people and show them the different ways of looking after country.’’

You can track the tagged green turtles via their satellite signal web page by clicking on the map:

 

 

The $30 million Kimberley Marine Research Program is funded through major investment supported by $12 million from the Western Australian government co-invested by the WAMSI partners and supported by the Traditional Owners of the Kimberley. 

Category:

Kimberley Marine Research Program

‘Big Data’ part of big plan for WA’s marine future

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AS PART of Big Data Week (April 20-26), ScienceNetwork WA invited the Pawsey Supercomputing Centre to share some of its insights on big data through a five-part series. Today, read about how the Western Australian Marine Science Institute (WAMSI) is meeting big data needs across all forms of marine research in WA.

WAMSI is making big data a key point in its Blueprint for Marine Science 2050, an initiative that will benefit researchers, governments, industry and the environment.

With around 20,000km of coastline, almost a third of Australia’s total, marine science is crucial for WA—and big data plays a key role for marine science according to WAMSI Data Manager Luke Edwards.

“Marine science is a broad church of disciplines—there are oceanographers, researchers looking into human environmental impacts, marine biologists and so on, and these are all producing large quantities of their own particular data sets.

“As well as this, there’s a great variety of data formats and that’s what can really make things difficult.”

The Blueprint, launched by Premier Colin Barnett in April, includes contributions from over 170 stakeholders from research, government and industry.

It aims to “…prioritise the key knowledge and capability gaps…” in WA marine science, and big data is playing a key role in this.

Big data is focused on more than simply big data in terms of size—it is also about making better use of the data collected, greatly benefiting marine science in WA.

“Where big data really links into the Blueprint is in underlying standards,” Mr Edwards says.

“You’ve got government agencies creating data, along with industry, academia and others but traditionally this data hasn’t really been shared.

“Part of the Blueprint is about creating common standards across WA, so then you can start making better use of that data.”

A large part of big data in WA marine science is focused on making data more available and open, which can greatly increase the use of that data.

“You don’t really just want to use the data you’ve collected once and then not be able to use it again—it’s about being able to reuse it,” Mr Edwards says.

By ensuring future WA marine science data is open and consistent, the Blueprint means that data collected can be used constructively by a range of bodies including researchers, industry, government and conservation groups.

“The Blueprint is crucial in terms of forward planning,” Mr Edwards says.

“WA has a huge coastline, which makes us a natural ‘hub’ for this type of push in marine science, which holds benefits for both WA and Australia.

“WAMSI in particular has been really proactive in terms of coordinating research, so this makes it a natural vehicle to coordinate marine science across WA.”

 

Aerial surveys generate first human activity maps for the Kimberley coast

Professor Lynnath Beckley from Murdoch University has led a team who spent two years using low altitude aerial surveys to monitor along the Kimberley coast and adjacent waters.

“People always talk about the remoteness and the emptiness of the Kimberley but this is the first time anyone has actually quantified human presence along the whole coast,” said Professor Lynnath Beckley.

“We were interested in finding out where people were spending time along the coast, and also what they were doing.”

The survey area ran along Eighty Mile Beach, Roebuck Bay, the Dampier Peninsula, King Sound, Buccaneer Archipelago and Camden Sound.

“This sort of information is vital for environmental managers and the Department of Parks and Wildlife to appropriately plan for biodiversity conservation and tourism, particularly as human activities in the area grow,” Professor Beckley said.

“The coast from Port Hedland to Wyndham has Traditional Owners, towns and communities, commercial endeavours, tourism and recreation activities and several marine parks.

“There are about 40,000 residents in the study area with more than 16,000 people living on the Dampier Peninsula.”

Results of the surveys showed that human use of the region is very seasonal and concentrated in particular areas of the coast with good road access.

As expected, the number of people along the shore and number of boats operating in coastal waters were much higher during the dry season from May to October. Nevertheless, local residents were observed to get out and about during the wet season to participate in various recreational activities.

“On Eighty Mile Beach people were mainly concentrated around the caravan park with anglers and their associated four-wheel drive vehicles clumped into about 30 kilometres of coastline,” she said.

“Camping during the dry season was largely confined to the larger caravan parks at Eighty Mile Beach and Port Smith, but also seen at Barn Hill Station and Cape Keraudren.

“This study has provided a spatially explicit benchmark of human recreational activities at the inception of the newly created Eighty Mile Beach Marine Park,” Professor Beckley said.

The research team also monitored boating in the central Kimberley region, through both aerial surveys and a collation of data about voyages of cruise vessels.

“Cruise vessels operate mainly from April to September between Broome and Wyndham with most of the vessels offering boutique expeditions with less than 20 passengers.

Montgomery Reef was the most popular destination in their itineraries with 275 visits by cruise vessels in 2013.

“Along with Montgomery Reef, the most popular sights for cruise vessels included Horizontal Falls, Raft Point, Prince Regent River and Talbot Bay. Passengers often go ashore in small boats to swim, fish and undertake scenic walks to view waterfalls, rock art and historical sites,” Professor Beckley said.

Read More:

Researchers take a snapshot of how we use the Kimberley coast

Listen to Professor Beckley’s presentation at the WAMSI Research Conference here: Lynnath Beckley, Murdoch University – Patterns of human use

 

The $30 million Kimberley Marine Research Program is funded through major investment supported by $12 million from the Western Australian government co-invested by the WAMSI partners and supported by the Traditional Owners of the Kimberley. 

Category:

Kimberley Marine Research Program

Oxygen and temperature levels examined in Kimberley reef

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MARINE scientists are using results from a recent reef study at Tallon Island, north of Broome, to develop predictive models for use on other reef systems in the Kimberley.

Speaking at the 2015 WAMSI Research Conference, University of Western Australia Associate Professor Ryan Lowe said the interactions occurring in these ‘tidally-forced’ reefs still remain unknown in relation to the widespread literature of wave-dominated reefs worldwide.

“There’s little known about the function and productivity of these reef systems so the goal is to really understand the nutrient dynamics in these types of environments,” he said.

A/Prof Lowe’s field program focused on detailed process-studies of the Tallon Island platform reef to understand the role of extreme environmental variability.

“We wanted to understand how the extreme environmental variability influences the benthic productivity of reef communities,” he says.

Using an array of synchronised current meters, tide gauges and thermistors (measurement and control instrument) A/Prof Lowe and his team researched primary production under extreme physical force by focusing on coral, algae and seagrass.

The results from the intensive field study, conducted three times during the dry and wet seasons, were used to measure the temperature variability across the intertidal reef.

Seagrass feels hot under the collar

A/Prof Lowe said extreme temperature variables were affecting the reef, with spatial patterns causing seagrass warming of up to almost 35 and 40 degrees Celsius.

“One of the striking things is the substantial tidal variations on these reefs,” he said.

“It is good in that it keeps these reefs from drying out during the day but it reduces the exchange of water in the ocean so it allows these extremes in temperatures and biogeochemicals to occur.”

At low tide the scientists were able to track the water mass through drifters and measure the changes in oxygen, nutrients and chlorophyll.

“From this information we can calculate influxes. From oxygen we can estimate rates in production and respiration and from the nutrients and chlorophyll we can estimate the uptake and release,” A/Prof Lowe said.

The scientists noticed extreme variations in oxygen, with primary producers such as seagrasses and algae producing a high amount during the daytime but with a noticeable decrease during the evening.

“However, we are getting twice as much post primary production in the seagrass zone as we are in the algal zone,” he says.

 

Listen to Ryan Lowe’s presentations at the WAMSI Research Conference 2015:

Ryan Lowe, UWA – Primary production

Ryan Lowe, UWA – Redefining sediment transport models over sensitive benthic habitats

 

The $30 million Kimberley Marine Research Program is funded through major investment supported by $12 million from the Western Australian government co-invested by the WAMSI partners and supported by the Traditional Owners of the Kimberley. 

The WAMSI Dredging Science Node is made possible through $9.5 million invested by Woodside, Chevron and BHP as environmental offsets. A further $9.5 million has been co-invested by the WAMSI Joint Venture partners, adding significantly more value to this initial industry investment. The node is also supported through critical data provided by Chevron, Woodside and Rio Tinto Iron Ore.

Category:

Kimberley Marine Research Program

Coast and Ocean: A community biodiversity exhibition

In March this year the Geraldton community joined UWA Oceans Institute Artist-in-residence Angela Rossen in a biodiversity project to discover and document the living things of the Geraldton beaches. 

Together they observed then drew, painted and photographed all the plants and animals of the coastal and marine environments.

Geraldton Primary School Biodiversity Painting

Members of the Birdlife Midwest Geraldton Group, Friends of Bluff Point and Geraldton and the Regional Herbarium Group contributed their special knowledge at the field and studio events.

The artworks that were created are now being presented to the public as a stunning exhibition at the WA Museum Geraldton open from 9th to the 22nd May.

 

Angela Rossen talks to St Mary’s students about  coastal biodiversity. Photo:J.Allen

 

“The people of Geraldton have really entered into the project with many participating in the field events and workshops,” Ms Rossen said. This exhibition is both artistically strong with beautiful renderings of the local biota as well as educational – it is a biology lesson in pictures.”   

“These artworks will take you on a tour from the top of the coastal dunes out to the fringing reefs showing all living things that make the beaches so special,” Angela Rossen said.  “You will find everything from plankton and tiny invertebrates, crustaceans, coral, seagrasses, seaweed, fish, sharks, rays, shore birds, reptiles, dune plants and much more.”

The project was supported by Community Arts Network WA, Department for Culture and the Arts and the project partners: Council of Greater Geraldton, The Northern Agricultural Catchment Council and the Western Australian Museum Geraldton.

Coastal Fauna workshop Photo: J. Kennedy

EVENT:  Coast and Ocean: A community biodiversity exhibition

WHERE: Western Australian Museum, Geraldton. Batavia Coast Marina

WHEN: 9-22 May, 2015

In The News: Coastline Winter Edition 2015

 

Attached files: 

PDF iconExhibition Flyer No1_web.pdf PDF iconExhibition Flyer No2_web.pdf

Marine science in top five State research priorities

Marine science has been recognised in the State Government’s priorities for the advancement and application of science that can help broaden the economy and create a new generation of jobs.

A Science Statement for Western Australia – Growing Western Australia, launched by the Premier and Minister for Science, Hon Colin Barnett MLA, outlines the State’s priorities and opportunities for scientific research.

“The Science Statement reinforces the importance of marine science to enhance environmental protection and improve the productivity of Western Australia’s marine industries,” Western Australian Marine Science Institution (WAMSI) CEO Patrick Seares said.

The five science priorities in the Science Statement were identified based on areas where Western Australia already has a comparative advantage and an appropriate base of research and industrial capability.

WAMSI, which is delivering two of the largest integrated marine research programs in Australia: the Kimberley Marine Research program and the Dredging Science Node, is identified as key in strengthening partnerships for effective collaboration.

“I’m very pleased that marine science has been acknowledged as essential to Western Australia and that WAMSI’s important part in the research landscape of Western Australia has been so well acknowledged,” Mr Seares said. “Our partners from the research sector, Government and industry should take credit for building a collaboration that is unique across Australia and delivering world class research that is responsible for the support of the marine sciences in this document.”

“The next stage of the Government’s science agenda will be to determine long term strategies in each of these priority areas,” he said.  “As we have recently completed The Blueprint for Marine Science 2050, marine science is ahead of the game and we look forward to working with the Government in shaping future priorities.”

WAMSI is a collaboration of 15 partner organisations that include State, Commonwealth, industry and academic organisations working together to deliver large-scale marine research

 

 

WAMSI Research Conference 2015

This article was originally published on an archived WAMSI website. Some media or links may appear missing or broken. You can use the search function to look for these, or contact info@wamsi.org.au for a specific request.

The partners of the Western Australian Marine Science Institution are delivering two of the largest marine research programs in Australia, alongside a raft of other important research.

At the 2015 Research Conference (30th March – 1st April 2015) WAMSI partners and affilates came together to discuss the progress and latest findings from over 50 projects.

Location: State Library of Western Australia, Perth.

Ministerial media statement

Click here to view the conference schedule.

Conference Proceedings (Abstracts)

Format

  • Day 1 (AM) Opening addresses, a summary of progress and future directions by the WAMSI partnership
  • Day 1 (AM) Presentations on other key WA marine research programs
  • Day 1 (PM) and Day 2 (AM)  Dredging Science Node – The end of stage 1: synthesis of contemporary knowledge on dredging impacts and presentations on each of the projects
  • Day 2 (PM) and Day 3 (AM/PM) Kimberley Marine Research Program – Mid-program summary review and findings and presentation on each project
  • Day 3 (PM) 12.15 – 1pm Special Event: Launch of the Blueprint for Marine Science 2050 by Hon. Colin Barnett MLA, Premier of Western Australia and Minister for Science; Chair of the Independent Blueprint Steering Committee E/Prof Alistar Robertson and WAMSI Chair Naomi Brown.

Audio of presentations

Launch of the Blueprint for Marine Science 2050 (1 April 2015)

Day 1 (March 30, 2015)

Session: Opening and keynote presentations

  1. Patrick Seares, WAMSI CEO – WAMSI – summary of progress and future directions  (presentation slides)
  2. Paul Vogel, EPA Chairman – Keynote presentation – Building a Science Knowledge base for Environmental Impact Assessment   (presentation slides)
  3. Hon Donna Faragher MLC, Parliamentary Secretary to the Premier, Minister for State Development, Science – Opening the 2015 WAMSI Research Conference
  4. Peter Klinken, Chief Scientist o Western Australia – Keynote presentation – Science priorities for Western Australia

Session 2

  1. Shaun Gregory, Woodside Energy, Senior Vice Pres. Science and Technology – Keynote Presentation – an industry perspective on strategic marine science.  (presentation slides)
  2. Patrick Seares, WAMSI CEO – Initiatives to improve collaboration on information, wildlife and estuaries.
  3. Margaret Byrne, Department of Parks and Wildlife – The role of science in conservation management.   (presentation slides)
  4. Michael Marnane, Chevron – Management based on science: Applying learnings from Gorgon to the Chevron Wheatsone dredging program (presentation slides)
  5. Bruce Elliot, GBRMPA – A QLD perspective on outcomes focused research for both dredging and marine park management.    (presentation slides)

Session 3: Dredging Node – Introduction and themes 2 and 3 (generation and transport of dredge plumes)

  1. Ray Masini, OEPA – Dredging Science Node Overview   (presentation slides)
  2. Tim Green, BMT JFA Consultants – Invited speaker: Dredging 101    (presentation slides)
  3. Graham Symonds, CSIRO – Theme 2/3 overview, Generation and transport of dredge plumes.   (presentation slides)
  4. Des Mills, Marine Environmental Reviews – Generation and release of sediments by hydraulic dredging  (presentation slides)
  5. Ryan Lowe, UWA – Redefining sediment transport models over sensitive benthic habitats   (presentation slides)
  6. Peter Fearns, Curtin – The light environment in turbid waters  (presentation slides)
  7. Graham Symonds, CSIRO – Modelling dredging generated sediment plumes.  (presentation slides)

Session 4: Dredging Node – Themes 5 & 6 (seagrass and sponges)

  1. Ian Le Provost, Environmental Consultant Association – Invited Speaker: Consultant’s perpective on WAMSI Dredging Science Node  (presentation slides)
  2. Paul Lavery, ECU – Theme 5 overview: Defining thresholds of primary producer response to dredge pressures  (presentation slides)
  3. Kathryn McMahon, ECU – Genetic variability, seasonal dynamics and recovery mechanisms of tropical seagrasses – update on field programs in northwest Australia.  (presentation slides)
  4. John Statton, UWA – Deriving pressure-response relationships of tropical seagrasses to dredge pressures – a laboratory approach  (presentation slides)
  5. Nicole Webster, AIMS – Theme 6 overview, Defining thresholds of filter feeder response to dredge pressures  (presentation slides)  (video 1)  (video 2)
  6. Muhammad Abdul Wahab, AIMS – Observations from pre-dredgings surveys of filter feeders at Onslow  (presentation slides)
  7. Brian Strethlow, UWA/AIMS – Indentifying, characterising and quantifying the effects of dredging on sponges (Porifera)   (presentation slides)  (video)
  8. Mari-Carmen Pineda, AIMS – Deriving pressure-response relationships of sponges to dredge pressures – a laboratory approach.  (presentation slides)

Day 2 (March 31, 2015)

Dredging Node – Themes 4 & 7 (corals and coral reproduction windows)

  1. Luke Smith, Woodside – Invited Speaker: Industry perpective on WAMSI Dredging Science 
  2. Ross Jones, AIMS – Theme 4 Overview, Dredging and Corals  (presentation slides)
  3. Alan Duckworth, AIMS – Specific and interactive effects of total suspended solids, light attenuation and sediment deposition on adult corals  (presentation slides)
  4. Rebecca Fisher, AIMS – Turning data into management recommendations: Predicting coral mortality based on water quality during dredging   (presentation slides)
  5. James Whinney, JCU – Measuring sediment deposition during dredging programs: development of an in situ deposition sensor   (presentation slides)  (video)
  6. Clair Stark, JCU – Measuring sediment deposition during dredging programs: modelling approaches  (presentation slides)
  7. Andrew Negri, AIMS – Theme 7 Overview, Effects of dredging on coral reproduction   (presentation slides)
  8. James Gilmour, AIMS – Review of coral reproduction in WA and current state of knowledge  (presentation slides)  (video)
  9. Gerard Ricardo, AIMS – Laboratory experimentation on the effects of dredging on fertilisation, larval development and settlement of corals (presentation slides)    (video 1)  (video 2)

Session 2: Dredging Node themes 8 & 9 (environmental windows for finfish and other organisms)

  1. Wayne Young, Pilbara Ports Authority – Invited Speaker: Dredging in the Pilbara – Ports perspective   (presentation slides)
  2. Euan Harvey, Curtin – Theme 8 Overview, Effects of dredging related pressures on critical ecological processes for finfish  (presentation slides)
  3. Gary Kendrick, UWA – Theme 9 Overview, Effects of dredging related pressures on critical ecological processes for other organisms  (presentation slides)

Session 3: Kimberley Node – Understanding the history and the habitats of the Kimberley

  1. Stuart Field, DPaW – Kimberley Node Overview  (presentation slides)
  2. Barry Wilson – Invited Speaker: The Kimberley Environment  (presentation slides)
  3. Lindsay Collins, Curtin – Geomorphology  (presentation slides)
  4. Andrew Heyward, AIMS – Benthic Biodiversity  (presentation slides)
  5.   (video 1)  (Video 2)
  6. Luke Edwards, WAMSI – Data Management  (presentation slides)
  7. Mick O’Leary, Curtin – Use of LIDAR in the Kimberley  (presentation slides)

Session 4: Kimberley Node – Physical processes and primary productivity – Feeding the System

  1. Greg Ivey, UWA – Oceanography  (presentation slides)
  2. Matt Hipsey, UWA – Biochemistry  (presentation slides)
  3. Andy Revill, CSIRO – Land-sea Linkages  (presentation slides)
  4. Ryan Lowe, UWA – Primary production  (presentation slides)
  5. Gary Kendrick and Renae Hovey, UWA – Seagrass and mapping productivity   (presentation slides)

Day 3 (April 1, 2015)

Session 1: Kimberley Node – Managing marine resources and values

  1. Tom Hatton, Invited Speaker: Western Australia’s Kimberley marine parks and WAMSI 
  2. Daniel Oades, KLC – Invited Speaker: Partnering with Indigenous communities  (presentation slides)
  3. Lynnath Beckley, Murdoch – Patterns of human use  (presentation slides)
  4. Jennifer Strickland-Munro, Murdoch – Social values and aspirations (presentation slides)
  5. Albert Wiggan, Nyul Nyul Rangers – Indigenous knowledge  (presentation slides)
  6. Fabio Boschetti, CSIRO – Management strategy evaluation  (presentation slides)

Session2: Kimberley Node – Ecological processes and change in the Kimberley

  1. Mat Vanderklift, CSIRO – Key ecological processes  (presentation slides)
  2. Ming Feng, CSIRO – Climate Change  (presentation slides)
  3. Verena Schoepf, UWA – Calcification  (presentation slides)
  4. John Keesing, CSIRO – Sediment records  (presentation slides)
  5. Oliver Berry, CSIRO – Connectivity  (presentation slides)

Session 3: Kimberley Node – Marine fauna and developing long term monitoring and research

  1. Brett Molony, DoF – Invited Speaker: Fisheries research in the Kimberley  (presentation slides)
  2. Scott Whiting, DPaW – Marine Turtles  (presentation slides)
  3. Michele Thums, AIMS – Humback Whale   (presentation slides)
  4. Andy Halford, DPaW – Crocodiles  (presentation slides)
  5. Mat Vanderklift, CSIRO – Dugongs  (presentation slides)
  6. Lars Bejdar, Murdoch – Dolphins  (presentation slides)
  7. Danny Rogers, AWSG – Shorebirds  (presentation slides)
  8. Peter Fearns, Curtin – Remote Sensing   (presentation slides)
  9. Kim Friedman, DPaw – Invited Speaker: WAMMP – KMRP research informing long term monitoring  (presentation slides)
  10. Patrick Seares, WAMSI, Close of conference and closing remarks 

GoPros underwater research tools of the future

An international team, including researchers from the Centre for Marine Futures at The University of Western Australia’s Oceans Institute, recently completed a study which has found GoPros to be a cheaper and easy to use camera for underwater videography, compared to more traditional cameras.

GoPros are increasingly being used for underwater videography because of their low-cost, widespread availability and small size.  This convenience makes them ideal to use for marine videography, however uncertainty has remained about how accurately these cameras could measure marine species.

The research team compared the use of traditional handheld cameras to GoPros in a pool-based study.  The GoPro camera and a traditional handheld camera were used to capture measurements of marine species to test the accuracy of both cameras.

Several factors were tested included the distance to the camera, the angle and the speed.  Although the accuracy decreased with the increased angles and distance for both systems, the precision of the GoPros was improved for marine life at less than five metres with an optical angle of 25 degrees. 

Researchers also examined the capacity of both cameras to estimate fish length by measuring the same fish on a coral reef with two baited remote underwater video systems, one fitted with a GoPro and one with a traditional camera.  The measurements were largely similar, supporting the use of the GoPro small action camera when used in combination with measurement protocols.

Lead author, fish ecologist Dr Tom B. Letessier said the research indicated that while the GoPros were generally less accurate than other cameras, the difference was not significant. 

“This study supports the use of small action cameras such as the GoPro system, which are cheaper and easy to use, compared with traditional and more expensive handheld cameras,” said Dr Letessier.

“The cheaper and easy to use cameras allows for more data collection, which is particularly good when we study rare big predator fish that are of conservation concern.”  

The study was originally published in international journal Journal of Experiment Marine Biology and Ecology.

Story courtesy: UWA Oceans Institute 

The adventures of team sawfish

Blog by Team Sawfish

Sweltering heat, mosquitoes, angry crocodiles and swarms of flies characterise the typical late dry season (September-November) in northern Western Australia. And it’s here that Team Sawfish has found itself for the past 15 years , as we continue our research on sawfish. This past October, Dr Ruth Leeney of Protect Africa’s Sawfishes and Dr Barbara Wueringer of James Cook University decided to brave these conditions and joined our team during our month long expedition on the Fitzroy River.

The main objective of our trip was to investigate how unnatural instream barriers, such as dams, may impact on the movement and health of the largetooth sawfish (Pristis pristis), which inhabits freshwater rivers and lakes as juveniles.Dams and other barriers in rivers and estuaries can block the movements of fish and which may prevent them from accessing food, spawning grounds or other important resources.

The Camballin Barrage, a small weir on the Fitzroy River used for irrigation for cattle and crops.

This work is part an ongoing project that is gathering information from several rivers throughout Western Australia.

The Fitzroy River is an ideal site for this study. It’s one of the largest known nurseries of the largetooth sawfish and it has instream barriers of various sizes, including a small weir (a type of dam often used for irrigation) and several road crossings. 

During our October trip we sampled various pools within the river that were located between the river mouth and 380 km (236 miles) upstream from the river mouth. From these pools we captured seven different sawfish. This is fewer fish than we typically see, and was largely due to the lack of captures of young of the year (YOY; fish pupped within the year). The number of YOY that we captured earlier in the year was also relatively low, which suggests this may have been a poor year for YOY.

All captured sawfish were only 2-3+ years old but still had an average length of 205 cm (6.7 feet)! In addition, the majority of these fish were recaptures of those that we had previously tagged with individually numbered Rototags (i.e. cattle ear tags). Two of these sawfish were initially tagged 2 to 3 years ago! Long-term recaptures like these allow us to gather some important information on the distribution, movements and growth of this species.

Although we can collect some of this vital information through recapturing sawfish for the few months of the year that we’re in the field, we also rely on local and visiting fishers to report their encounters. (see instructions below on how to report an encounter with a sawfish).

The sawfish that we did capture were also tagged with small acoustic transmitters. These transmitters emit a unique acoustic signal that is picked up and recorded by receivers, which we have installed throughout the river. Data from these transmitters and receivers will help us to better understand sawfish movements and how dams and river levels affect them.

Although we tag the animals in the dry season, it is the data from the wet season we are most interested in. Only during the wet season are the barriers submerged by rising river levels, and we want to know at what river level sawfish move beyond these barriers.

Release of a tagged largetooth sawfish

As well as capturing the largetooth sawfish, we had hoped and expected to find the smaller dwarf sawfish (Pristis clavata), which we have been monitoring over the last few years. Although the largetooth sawfish is the only sawfish that lives in freshwater for long periods of time, the dwarf sawfish, which lives in marine and estuarine environments, is attracted to the estuarine pools of the Fitzroy River in the late dry season, when these pools become more salty (around 35 ppt; similar to the ocean). This increase in salt in the late dry season is due to a decrease in freshwater flow and the constant transport of ocean water into the pools by the large tides. Typically during this time we primarily find dwarf sawfish in the estuarine pools, as the majority of the largetooth sawfish appear to leave the area. This year however, we were surprised to find a couple largetooth sawfish but unfortunately did not find any dwarf sawfish.

After a month in the field our food supplies, energy levels and time ran out. As we left the sawfish and the river behind, our team agreed that in spite of a few minor setbacks our trip was a success. We were able to tag a few new sawfish and collected some important recapture data. This will help us to better understand and inevitably help to advance conservation efforts for these threatened sawfish.

Although, we had to finally part ways with our esteemed and much appreciated colleagues, we had enjoyed the time spent with them and the memories of fly bites, tasty porridge, not so tasty tree sap and most importantly, the sawfish.

Pictured is the October 2014 Team Sawfish field crew. Missing are Dr David Morgan and James Keleher.

Pictured is the October 2014 Team Sawfish field crew. Missing are Dr David Morgan and James Keleher.

To report a sawfish captured in Western Australia and for more information regarding Team Sawfish please visit http://www.freshwaterfishgroup.com/team-sawfish.php. If you encounter a tagged or untagged sawfish outside of Western Australia please visit the Sawfish Conservation Society at www.sawfishconservationsociety.org, or the International Sawfish Encounter Database at www.flmnh.ufl.edu/fish/sharks/sawfish/sawfishdatabase.html.

This research was funded by Chevron Australia and was made possible by the Western Australian Marine Science Institution.

 

 

 

Category: 

Sawfish Project

Northwest seagrass in a world of its own (in the lab)

In the second part of our report into measuring the effects of light reduction and sediment burial to determine the capacity for northwest seagrasses to withstand change, we move from the field to the lab for some surprising results.

The WAMSI Dredging Science Node project has brought together researchers from Edith Cowan University (ECU), The University of Western Australia (UWA) and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) to test tolerance levels that have

UWA’s seagrass growth facility (Crawley campus)

previously never been determined for seagrass species in the far northwest.

Dr John Statton manages the research’s experimental tank system at UWA’s seagrass growth facility (Crawley campus) where the effects of light stress and sediment burial are being measured under controlled conditions on three commonly co-occurring northwest Australian

tropical seagrass species (Halodule uninervis, Halophila ovalis and Cymodocea serrulata).

“We’ve been keeping plants under different light intensities for a number of weeks now. It was quite clear that within the first three weeks the plants at low light intensities (4 and 11% surface irradiance) had lower photosynthetic rates and growth rates than unshaded plants.

“Some of the responses were as expected but what was interesting is that it took a long time for all except one of the species, Halophila ovalis, to die,” Dr Statton said.

Halophila ovalis

Halophila ovalis has the smallest leaf and storage reserves of the three seagrasses under observation and is the only variety of the three that can also be found off the southwest coast.

In the second stage of the research, the plants were subjected to fine sediment (Rocla Quarries WA sponsored UWA with high-grade fine sediments) burial at a depth of between 4mm to 70mm but the effects of light were found to have a far greater impact.

“Only the deepest burial treatments resulted in in some adverse effects,” Dr Statton said. “The seagrasses adapted and grew vertically to new sediment heights then, much like suburban lawns, they put out runners spreading across the new sediment surface. So their initial response to being buried in sediment was to increase the length of their leaves then grow vertically.”

The next step to the lab work will be to install the combined sediment burial and light interaction experiment to look at answering the questions as to what synergies there are when the stresses are combined.

 

The first part of this story was published in the February WAMSI Bulletin:

WAMSI research finds northwest seagrass in a world of its own (Part 1 – in the field)

Related Links:

Tropical Seagrass examined for light pressures (article by Science Network WA)

 

The WAMSI Dredging Science Node is made possible through $9.5 million invested by Woodside, Chevron and BHP as environmental offsets. A further $9.5 million has been co-invested by the WAMSI Joint Venture partners, adding significantly more value to this initial industry investment. The node is also supported through critical data provided by Chevron, Woodside and Rio Tinto Iron Ore.

Category:

Dredging Science