Carp are a major problem in Murray Darling catchment. Knowing more about Carp in our catchment is really important! They are one of our worst aquatic pests and can breed up very quickly. Mapping Carp hotspots and where they breed is important for understanding their behaviour and identifying opportunities for control. Carp are often thought to require large and warm wetlands to breed, but we have very few of those types of wetlands, and we still have lots of Carp!
Carp Loves 20°c takes its name from Carp's tendancy to display breeding behaviour when water temperature reaches around 20°c. The water is warming and Waterwatch would like you to keep an eye out for behaviour such as that seen in the You tube video below and log your sightings on the FeralFishScan website. Such infomation will help us to build a picture of where Carp are breeding in the upper Murrumbidgee and to look at more effective measures to control them.
Do you know which fish species you've seen? There are 5 major feral fish species that live in the Upper Murrumbidgee catchment. They are common carp, redfin perch, eastern gambusia, oriental weatherloach, and goldfish. There are also some native species that can be easily mistaken for feral fish. To find out how to identify feral fish, click here.
At the beginning of October Carp have already been breeding seen at the downstream end of Sullivan's Creek
This photo was taken at Sullivan's Creek. Carp have been regularly gathering in circles near the surface of the water. No one is really sure why they do this but it believed to be a social exercise rather than a feeding/breeding activity.
This footage taken by Dr Danswell Starrs shows Carp spawning at McKellar Wetlands in Belconnen during October 2015.
Carp are easy to spot when they're spawning as they splash around in shallow water dispersing their eggs throughout the water plants.
Carp eggs taken on the same day at McKellar Wetlands. Eggs are 3mm in diameter and take approximately a week to hatch.
A single, large female can produce up to 1.5 million eggs in a single spawning event!!
Since European settlement, the deliberate or accidental introduction of non-native fish into Australian freshwater ecosystems has resulted in the establishment of many populations of pest fish species. These species are broadly considered as 'pests' because they threaten native fish species, river health and aquatic ecosystems by:
FeralFishScan is a new community website dedicated to collecting evidence of feral fish from our freshwater rivers.
Species such as European carp, Redfin perch, Goldfish, Gambusia and Oriental weatherloach are found in many rivers, but exactly where they occur is poorly known. These species are directly impacting on our native fish and aquatic fauna in many ways, including the spread of disease/parasites and predation on the young and eggs of native species.
Some pest fish can also affect the health of our rivers, lakes and creeks by compounding the effects of degradation from other sources, which in turn can affect the ability for native fish and aquatic fauna to thrive and breed.
Although we know roughly how these species are impacting our rivers, lakes and creek systems, we don’t have detailed catchment-wide data on where these pest fish are found or their numbers. We need your help to address this knowledge gap to better manage the effects of pest fish throughout our wonderful catchment.