Low structural complexity of nonnative grassland habitat exposes prey to higher predation.

摘要: The structural complexity of vegetation can have profound effects on the hunting efficiency predators, thereby affecting their intake rate prey. While studies shown that play an important role in managing unwanted impacts it is less clear how invasive affects vulnerability terrestrial Short nonnative pasture species bred for agricultural production, example, are highly and pervade grassland ecosystems worldwide. They generally low compared with taller native they often displace. We conducted controlled experiments to test whether pastures expose fauna greater predation risk. Survival invertebrates (tethered locusts) subject by mammalian insectivores (European hedgehogs) (0.10 per 24 h; 95% CI, 0.08-0.13) was than one-half structurally complex perennial tussock (bunch) grass (0.24; binomial 0.18-0.31). A significant positive relationship apparent between (grass dry stem density) surrounding each locust survival. In a second experiment, survival locusts placed solely increased decreasing density tussock, presumably reflecting fewer resource-rich patches which predators could focus. These results demonstrate invasion simple exposes prey risk predation. This concerning from global nature conservation perspective given conversion nearly world's temperate grasslands agriculture includes range invasive, simple, nonnative, plant species. Minimizing maintaining restoring habitat structure may be useful option reducing