Journal of Orthoptera Research (2017) 26, 7-10

David H. Branson (2017)
Grasshopper species composition shifts following a severe rangeland grasshopper outbreak
Journal of Orthoptera Research 26 (1), 7-10
Abstract: Little is known about how grasshopper species abundances shift during and following severe outbreaks, as sampling efforts usually end when outbreaks subside. Grasshopper densities, species composition and vegetation have infrequently been sampled during and after a severe outbreak in the western U.S., which is needed to better understand the cause of outbreaks and population declines. In this study, grasshopper densities, species composition and vegetation were monitored at a northern mixed rangeland site from 1999 to 2003 where densities reached 130 per m² during a severe outbreak. Phoetaliotes nebrascensis (Acrididae: Melanoplinae) comprised 79% of the outbreak in 2000, but declined to 3% by 2003. The dramatic shifts in proportional and actual abundance of P. nebrascensis over a 5 year period illustrate that species dominance can change rapidly, even for a highly dominant outbreak species. The difficulty of fully understanding factors causing shifts in grasshopper populations is illustrated by population declines in all species observed in 2002 and 2003. The data can help predict the intensity and decline of outbreaks and points to the critical importance of long term simultaneous monitoring of grasshopper densities, species composition and vegetation for outbreak prediction.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: English)
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Database assignments for author(s): David H. Branson

Research topic(s) for pests/diseases/weeds:
population dynamics/ epidemiology

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Melanoplus sanguinipes	Grasses/turf/rangeland	U.S.A. (NW)
	Ageneotettix deorum	Grasses/turf/rangeland	U.S.A. (NW)
	Phoetaliotes nebrascensis	Grasses/turf/rangeland	U.S.A. (NW)