Supporting Recovery of the Recreational Fishing Industry in Bushfire Damaged Areas: Year 1 Results
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Supporting recovery of the recreational fishing industry in bushfire damaged areas: Year 1 results Fiona Gavine, Nick Taylor, Taylor Hunt, Adrian Kos, John Douglas, Kylie Hall, Daniel Steel February 2010 Fisheries Victoria Research Report Series No. 43 If you would like to receive this ISSN 1448‐7373 information/publication in an ISBN 978‐1‐74217‐816‐5 accessible format (such as large print or audio) please call the Authorised by the Victorian Government, Customer Service Centre on: 1 Spring Street, Melbourne 136 186, TTY: 1800 122 969, Published by the Department of Primary or email Industries. [email protected] Copies are available from the website: www.dpi.vic.gov.au/fishing © The State of Victoria, Department of Primary General disclaimer Industries, 2010. This publication may be of assistance to you but This publication is copyright. No part may be the State of Victoria and its employees do not reproduced by any process except in accordance guarantee that the publication is without flaw of with the provisions of the Copyright Act 1968. any kind or is wholly appropriate for your particular purposes and therefore disclaims all Preferred way to cite this publication: liability for any error, loss or other consequence Gavine F, Taylor N, Hunt T, Kos A, Douglas J, which may arise from you relying on any Hall K, & Steel, D (2010). Supporting the information in this publication. recovery of the recreational fishing industry in bushfire damaged areas: Year 1 results. Fisheries Victoria Research Report Series No. 43. Supporting the recovery of the recreational fishing industry in bushfire damaged are ii Foreword Victoria has a fire‐prone landscape, with three major bushfires occurring in 2003, 2006–07 and 2009. In 2003 and 2006–07, vast tracts of upland bushland in north‐east and alpine areas of Victoria were burnt (2.5 million hectares in total). These areas host Victoria’s most important recreational trout fisheries. This report presents the results for the first year of a project (up to June 2008) to investigate the impact of the 2006–07 bushfires on recreational fisheries and associated regional economic and social aspects, which was commissioned under the Victorian Government’s “Bushfire Recovery Initiative” in July 2007. Supporting the recovery of the recreational fishing industry in bushfire damaged areas iii Supporting the recovery of the recreational fishing industry in bushfire damaged areas iv Executive Summary This project investigated the impact of bushfires An important consideration in determining the on recreational fisheries in the north‐east, alpine impact of bushfires on aquatic ecosystems is the and Gippsland area of Victoria. It was funded climatic conditions pre and post‐fire. In the case by the Victorian Government’s “Bushfire of the 2006–07 Victorian bushfire, extreme events Recovery Initiative”. The specific objectives of were recorded before (long‐term drought), this project in Year 1 included: during and after (floods) the fire event. • To monitor important recreational fisheries in Data analysis found that there appeared to be no the bushfire damaged areas to assess the systematic differences in either abundance or extent and magnitude of impacts on fish occurrence of important recreational species as a populations (Phase I: Broadscale assessment) result of fire intensity. Significant effects were, • To conduct more detailed monitoring at however, found for the effects of floods that selected locations to assess the recovery of occurred in June 2007 on recreational species. impacted fish populations over time (Phase II: Detailed monitoring took place on five rivers in Detailed monitoring) the bushfire affected area and at one control site. • To determine factors that drive the behaviour Four of the six sites had historical data with of recreational fishers who have in the past, or which the 2008 data could be compared. The may in the future, fish in the bushfire area. other two rivers were included to provide Two major bushfires affected the north‐east and information on the status of fish populations in alpine areas of Victoria in 2003 and in 2006–07 these rivers, but detailed analysis of the data was with large areas of land burnt during both not possible. events. The most important recreational fishery As found in the broadscale assessment, rivers in in this region is salmonids (brown and rainbow catchments north of the GDR (King Parrot Creek, trout) which thrive in the cool upland waters and the Howqua, Thowgla and Buckland Rivers) although anglers also target other species (e.g. generally had greater numbers of fish and a crayfish, blackfish, eels and redfin). greater diversity of species than those south of The broadscale assessment undertaken for this the GDR (Crooked and Wellington Rivers). Very study provides a qualitative overview of the few fish of any kind were found in the status of fish populations in six catchments and Wellington River within the Thomson catchment. at seventy‐five sites in the area affected by the It is thought that this could be due to the long‐ 2006–07 bushfire. The results show that the lasting impacts of the severe flood that hit that diversity and abundance of both recreational and catchment in 2007. other fish species varied between and within A key finding of the detailed monitoring surveys catchments. in 2008 was the disruption of brown trout Generally speaking, catchments south of the recruitment in bushfire affected river systems in Great Dividing Range (GDR) (Thomson, Mitchell the year immediately post‐fire. This was and Tambo) appeared to have been more affected particularly evident in the Howqua River (2008, than catchments north of the GDR (Ovens, Upper post 2007 fire) and the Thowgla River (2004 post Goulburn and Kiewa). No fish at all were found 2003 fire) . Brown trout recruitment failure at 7 out of 75 sites (9% of sites), 6 of which were appears to be more pronounced where rainbow south of the GDR. No recreational species were trout are also present in the system. found at 24 of the 75 sites surveyed (32%), 22 of For the purposes of this study “recovered” (or which were south of the GDR. In the Tambo un‐impacted) populations were defined at the catchment, trout were found none of the sites outset as: surveyed (100%); in the Thomson and Mitchell catchments, trout were found at only 33% and 64% of sites, respectively. This contrasts with catchments north of the GDR where trout were found at far more sites: Ovens (72%), Upper Goulburn (93%) and Kiewa (100%). Supporting the recovery of the recreational fishing industry in bushfire damaged areas v • Fish population abundances recorded in 2008 • Howqua River. Recovery time 1‐2 yrs. surveys were comparable with those found in Brown trout populations can be re‐colonised previous surveys that were not influenced by from Lake Eildon or other refugia. bushfire or other major disturbances • Crooked River. Recovery time 2‐5 years. • A number of length classes were present Recovery will depend on climatic conditions • Evidence of successful recruitment in 2007. becoming more favourable for trout (end of drought). There are fish in the upper Within this definition, rivers that could be catchment that could re‐colonise downstream classified as “un‐impacted” were the King Parrot reaches. Creek (Control) and the Thowgla River (burnt in • Buckland River. Recovery time 2‐5 years. 2003). Rivers that show signs of continuing Recovery will depend on climatic conditions impact in the 2008 survey were the Howqua and becoming more favourable for trout (end of Crooked Rivers, particularly with respect to drought) and the presence of fish to recolonise brown trout populations. Although there were in the Ovens River and Upper Buckland. no historical data available, the Wellington and Buckland Rivers would also fall within this • Wellington River. Recovery time >10 years. “impacted” classification due to lack of fish, lack Catchment subject to severe flooding and of multiple length classes and/or lack of evidence erosion. of recruitment. A key concern now is how long recovery may take in these systems. Where bushfire alone was the major disturbance in a catchment (e.g. the Upper Goulburn) trout populations appeared to cope well with “good” and “average” populations recorded at most sites during the broadscale assessment. Although the detailed surveys picked up more subtle impacts on brown trout recruitment in the year after bushfires, it is expected that the recovery of fish populations in catchments only affected by the bushfire will be rapid (within 1‐2 years) as seen in the Thowgla River after the 2003 fire. Catchments that also had river systems affected by severe drought and some flooding (e.g Ovens, Tambo and Mitchell) had a high proportion of sites with no trout or “poor” populations. These catchments generally provide marginal habitat for trout and recovery will depend on climatic conditions becoming more favourable for trout (i.e. cooler and wetter). In the Thomson catchment where severe flooding caused massive erosion and landscape‐changing impacts, the timelines to recovery are likely to be far longer. An analysis of how the large scale mass‐transport of material has affected trout habitat in the river system will be required before estimates of recovery times can be made. In summary, the potential for recovery of impacted fish populations in this study was estimated as follows: Supporting the recovery of the recreational fishing industry in bushfire damaged areas vi Table of Contents Foreword...............................................................................................................