title: Use of three monitoring approaches to manage a major Chrysosporum ovalisporum bloom in the Murray River, Australia, 2016.
abstract: An unusual bloom of Chrysosporum ovalisporum (basionym Aphanizomenon ovalisporum) occurred for the first time in the Murray River and distributary rivers in New South Wales, Australia, from mid-February to early June 2016. At its greatest extent, it contaminated a combined river length of ca. 2360 km. Chrysosporum ovalisporum usually comprised >99% of the total bloom biovolume at most locations sampled, which at times exceeded 40 mm3l-1. The origins of the bloom were most likely reservoirs on the upper Murray River, with cyanobacterial-infested water released from them contaminating the river systems downstream. An integrated approach using three analytical methods: (1) identification and enumeration by microscopy, (2) multiplex quantitative polymerase chain reaction (qPCR), and (3) toxin analysis, was used to obtain data for the assessment of risk to water users and management of the bloom. qPCR indicated some cyrA and stxA genes responsible for cylindrospermopsin and saxitoxin biosynthesis respectively were present, but mostly below the level of quantification. No mcyE genes for microcystin biosynthesis were detected. Toxin analysis also revealed that cylindrospermopsin, saxitoxin and microcystin were all below detection. Lack of measurable toxicity in a species usually considered a cylindrospermopsin producer elsewhere meant the possibility of relaxing management guidelines; however, high (Red) alerts needed to be maintained due to risk to water users from other biohazards potentially produced by the cyanobacteria such as contact irritants. A three-tiered monitoring strategy is suggested for monitoring cyanobacterial blooms to provide enhanced data for bloom management.
authors.affiliation: DPI Water, Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Private Bag 4008, Narellan, NSW, 2568, Australia.
authors.forename: Adam
authors.initials: A
authors.lastname: Crawford
authors.affiliation: DPI Water, Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Private Bag 4008, Narellan, NSW, 2568, Australia.
authors.forename: Jon
authors.initials: J
authors.lastname: Holliday
authors.affiliation: DPI Water, Department of Primary Industries, PO Box 829, Albury, NSW, 2640, Australia.|Water NSW, Albury, NSW, Australia.
authors.forename: Chester
authors.initials: C
authors.lastname: Merrick
authors.affiliation: DPI Water, Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Private Bag 4008, Narellan, NSW, 2568, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Brayan
authors.affiliation: Diagnostic Technology, 7 Narabang Way, Belrose, NSW, 2085, Australia.|School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: van Asten
authors.affiliation: DPI Water, Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Private Bag 4008, Narellan, NSW, 2568, Australia. bowlinglimnology@gmail.com.|Centre for Ecosystem Science, University of New South Wales, Sydney, NSW, 2052, Australia. bowlinglimnology@gmail.com.|, 3 Shrike Place, Ingleburn, NSW, 2565, Australia. bowlinglimnology@gmail.com.
authors.forename: Lee
authors.identifier: http://orcid.org/0000-0002-0360-0410
authors.initials: L
authors.lastname: Bowling
mesh_terms: D015169:Colony Count, Microbial; D003247:Conservation of Natural Resources; D000458:Cyanobacteria / Q000235:genetics / Q000302:isolation & purification*; D004784:Environmental Monitoring / Q000379:methods*; D005068:Eutrophication; D060885:Multiplex Polymerase Chain Reaction; D009517:New South Wales; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045483:Rivers / Q000382:microbiology*; D014739:Victoria
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: Bloom management; Cyanobacteria; Microscopy; Toxin analysis; qPCR