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Providing evidence to improve practice

Action: Remove/control non-native invertebrates Terrestrial Mammal Conservation

Key messages

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  • One study evaluated the effects on mammals of removing or controlling non-native invertebrates. This study was in the USA.



  • Abundance (1 study): A replicated, controlled, before-and-after study the USA found that after the control of red imported fire ants, capture rates of northern pygmy mice increased.


Supporting evidence from individual studies


A replicated, controlled, before-and-after study in 1989–1990 in coastal grassland and shrubland in Texas, USA (Killion et al. 1995) found that after the control of red imported fire ants Solenopsis invicta, capture rates of northern pygmy mice Baiomys taylori increased. Northern pygmy mouse capture rates increased more where red fire ants were controlled (from 6–9/plot during first three months (over winter) of ant control to 19–25/plot nine months later) than in uncontrolled areas (8–9/plot during first three months of ant control to 11–15/plot nine months later). Captures were similar between plots in the summer before treatments began (19–27 mice/plot). In June 1989, two 110 × 130-m plots were established at the Welder Wildlife Foundation refuge. Each plot was divided into a treatment area and an untreated area. In treatment areas, an aerosol insecticide (active ingredient 0.7% pyrethrin) was injected directly into ant mounds while a bait insecticide (active ingredient 0.88% amidinohydrazone) was deployed monthly, from November 1989 to October 1990. Between June 1989 and October 1990, mice were sampled for four days/month using 108 baited Sherman live traps/plot. Animals were marked at first capture, and only included in analysis when caught for a second time.

Referenced papers

Please cite as:

Littlewood, N.A., Rocha, R., Smith, R.K., Martin, P.A., Lockhart, S.L., Schoonover, R.F., Wilman, E., Bladon, A.J., Sainsbury, K.A., Pimm S. and Sutherland, W.J. (2020) Terrestrial Mammal Conservation: Global Evidence for the Effects of Interventions for terrestrial mammals excluding bats and primates. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.