Thursday, March 11, 2010

Creek Crew - Redlands

Hilliards Creek Redlands

Hilliards Creek Redlands

The fish trap.

Fly-specked Hardyhead, native freshwater fish.

Today I joined the Creek Crew group at Redlands on their monthly outing to undertake water monitoring and as a bonus this month, catch and identify freshwater fish. We visited three sites along Hilliards Creek; water quality indicators such as pH, conductivity, turbidity, dissolved oxygen, temperature and salinity were recorded. Aquatic species, weather, rainfall and water flow conditions were also noted. With heavy rain and flooding in the last month it was interesting to see how the creek banks had held up and results of the water testing.
Each site varied, but overall the creeks looked healthy with lots of dragonfly and damselfly activity. Bull rush and lomandra vegetation has assisted in reducing erosion and stabilised creek banks during recent flooding, with plenty of debris marooned high indicating recent water levels.
For me the highlight of today's trip was the trapping of freshwater fish for identification before being released back to the creek. Three traps were set in different locations of the creek edge, some deep, others floating, each using prawn flavoured dry cat food as bait. After 30 minutes we checked the traps to see what the creek held in the way of freshwater fish. Wow, there were lots. Four varieties of native fish were identified - Empire Gudgeon, Fly-specked Hardyhead, Firetail Gudgeon and Crimson-spotted Rainbow fish, what fabulous names. One exotic variety, Swordtail, was also caught. The main way to identify between native and exotic freshwater fish is to look at the Dorsal fin ( top of the fishes body), native freshwater fish have two dorsal fins while exotic fish have one. I had a great time today, there is so much to learn, but now I have a little more of an idea about the wonderful diversity of life in creeks. Special thanks to bushcare officers Boyd and Kylie for sharing your knowledge so freely, what a great way to learn.

1 comment:

  1. Thank you for posting this interesting information. We are just coming out of a deep winter and getting ready to start our water monitoring activities here in Central Wisconsin. USA. (Okay, in amount another month or so.)We will measure similar "water quality indicators." We hope to get interesting input like this. Thank you again.