Diary anglers monitoring Kiewa River
The Victorian angler diary program has been operating in the Kiewa River since 2008/09 and is currently funded by the Recreational Fishing Grants Program. Volunteer anglers have been contributing detailed information about their fishing trips including their time spent fishing, fishing location, species targeted and caught, fish lengths, number of rodsand baits and hook type/sizes used.
Information collected by these volunteer anglers improves our understanding of fish stocks in the Kiewa River in particular for brown and rainbow trout by providing information on:
- Abundance of fish. Catch rates (fish caught per angler hour) of key species can be used as a measure of fish abundance. Catch rates can indicate whether there has been an increase or decrease in the population over time
- Health of the fishery. The length and ages of fish caught by anglers indicates the health of the fishery and can be used to forecast catch trends 2 to 3 years in advance
- Profile of the fishery. Angler diarists give an insight into the species targeted and caught in the Kiewa River as well as Information on which fish are kept and released.
- Local knowledge. Anglers provide their opinions on the status of key fish stocks and comment on trends in fish abundance over the past 5 years.
Volunteer anglers contribute to the angler diary program as either a 'research' angler or a 'general' angler. General anglers record information from their normal fishing trips. Research anglers target key species and if necessary alter their fishing techniques to catch the largest possible sizerange of the targeted species.
Abundance of fish
Angler diarists recorded 188 trips for trout in the Kiewa River during 2010/11.
The catch rates (fish per angler hour) of brown trout have increased since 2008/09 while the catch rates of rainbow trout have remained similar over the past three years. On average, diary anglers caught a brown trout every hour and a rainbow trout every 3 hours while fishing in the Kiewa River.
Health of the fishery
Data collected by angler diarists in the Kiewa River over the past three years suggest that the trout population, while variable from year to year, is resilient and in a healthy condition.
Angler diarists measured 454 brown trout and 174 rainbow trout in the Kiewa River during 2010/11. Anglers caught a wider size range of brown trout and a higher proportion of larger fish (> 40 cm TL) compared with rainbow trout.
Brown trout ranged in length from 15 to 58 cm Total Length (TL); 20% were 40 cm TL or greater. Rainbow trout ranged in length from 15 to 45 cm TL; 2% were 40 cm TL or greater. A longer time-series of data is needed to better understandthe stock status of these species.
- Thirteen angler diarists were asked how last years fishing compared with the previous 3–4 years. Most anglers thought:
- The abundance of small trout had increased or was similar in the past year compared to the previous 3–4 years
- The abundance of large trout had increased in the past year compared to the previous 3–4 years.
- The average size of trout in the Kiewa River had increased over the past 5 years
- Trout stocks in the Kiewa River are in good condition.
Angler perceptions of the trout population in the Kiewa River in the past 12 months compared to the previous 3–4 years.
Some reasons why angler diarists thought the abundance and size of trout had increased and that stocks were in good condition were as follows:
- 'Over the past 10 years there has been an abundance of small trout; numbers have been similar over the past 5 years'
- 'Best year in awhile; caught 3 big rainbows recently'
- 'A lot of trout in the past 2–3 years. The pondage is stocked every year so some get out over the spillway. Also lots of food around because of the wet summer and water levels have been higher so the river has been harder for anglers to access'
- 'The number of trout have increased due to the health of the river'
- 'Fish in great condition. The last wet summer and winter is resulting in great fish'
- 'The trout are getting bigger, or maybe I'm getting smarter'
- 'The river changed after the floods but the pools are reestablishing'
- 'Trout stocks are good and improving. Kiewa is fishing the best for 10 years.'
Further information on the Angler Diary Program
If you would like to get involved contact the Fisheries Research Branch on (03) 5258 0111