New York Natural Heritage Program
Nine-spotted Lady Beetle
Coccinella novemnotata Herbst, 1793
Insects

Threats [-]
Agricultural land has been declining in New York since the 1880s resulting is less suitable habitat for many lady beetle species. Between 1940 and 1997, there was a 57% decline in farmed land in New York (Harmon et al. 2007). It appears that competition with other aphid-eating insects, such as the non-native Coccinella septempunctata (seven-spotted lady beetle), may be leading to smaller nine-spotted lady beetles. This may result in higher mortality and lower fecundity (Losey et al. 2012, Cornell University 2013). Losey et al. (2012) found that simply limiting the number of aphids has a significant effect on the C. novemnotata size. C. novemnotata appears to be sensitive to pesticide use (Stephens and Losey 2003).

Conservation Strategies and Management Practices [-]
Preservation of farmland would maintain or increase suitable open habitat. Pesticide use should be avoided when possible. If pesticide use cannot be avoided: use chemicals that target only the pest, treat only infested areas, and select chemicals that do not persist.

Research Needs [-]
Additional research is needed to determine the effects of competition with other coccinellids. Further studies on lab rearing and reintroduction are needed.