Carp virus causes multi-decadal population collapse among ‘Rats of the River’ in iconic Mississippi

Tuesday 16 May 2017

The National Carp Control Plan Coordinator, Matt Barwick said a new scientific paper out of the United States offers clues as to how the highly invasive and environmentally destructive reign of the ‘rats of the river’ could be stopped.

Recent research shows the very same carp virus being considered for use to control carp in Australia is the chief suspect in causing the multi-decadal population collapse among Common carp in the Upper Mississippi River System in the United States. 

Mr Barwick said the research paper titled; ‘Widespread and enduring demographic collapse of invasive common carp (Cyprinus carpio) in the Upper Mississippi River System’ made for exciting bed time reading.

“This study shows carp numbers dramatically declined along one of the largest and most iconic river basins in North America since the 1990’s after nearly a century of carp infestation, and have remained suppressed since then”.
“Importantly, these researchers looked at a range of possible causes for the population crash in carp, and concluded that the Carp virus currently being considered for use in Australia was the most likely cause”.

“It was particularly interesting to see that the richness and abundance of native species including Bluegill – a fish species native to North America that angler like to catch – exploded as carp numbers dwindled” (see figure below from the study).

Figure 1 Catch rates of Carp (red) and Bluegill (blue) in the Upper Illinois River (Source: Gibson-Reinemer et al. 2016)

“This is significant. Everywhere we go people are keen to learn more about the likely impacts of the virus on carp numbers if released. Many also ask whether it will be effective in promoting recovery of our iconic native species, some of whom have all but perished the during the carp’s reign. These results are a real-world demonstration that when a greedy resource-hog like carp are controlled in a big river system, native species thrive”

Mr Barwick said it is important that we continue to learn from research on carp impacts, and the impact of the carp virus. 

“We will continue sharing updates on relevant research from Australia and overseas on the National Carp Control Plan’s website www.carp.gov.au to keep the Australian community informed on progress with this important national initiative”

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