Document Details

Title Variation in Densities of the Salt Marsh Katydid Orchelimum fidicinium over Space and Time
Archive All Files / Documents / Publications / Journal Articles

Densities of Orthoptera typically vary greatly over space and time. The most important salt marsh orthopteran on the East Coast of the US is Orchelimum fidicinium, an omnivore that feeds on cordgrass (Spartina alterniflora) and arthropods. We examined spatial (34 sites) and temporal (4 sites, 17 years) variation in O. fidicinium density in coastal Georgia. Sites with considerable adjacent upland habitat had higher densities of O. fidicinium than sites with little adjacent upland. Grasshoppers fed S. alterniflora from both types of sites did not differ in growth rates, ruling out food quality as an explanation. We speculate instead that O. fidicinium require terrestrial habitat for reproduction or escape from predators during extreme high tides. At four sites where O. fidicinium was common, densities varied greatly among years. Regressionmodels indicated that current year plant biomass (three sites) or previous year plant biomass (one site) was the best predictor of O. fidicinium density. Relationships between O. fidicinium and current year plant biomass were typically negative (more grasshoppers in years with lower plant biomass). A possible explanation for this pattern is that plant nutrientsmay be diluted in years with high plant biomass.We found little evidence that density of animal prey (Prokelisia spp.) or abiotic factors affected O. fidicinium densities. Our study illustrates the value of examining population densities across multiple sites and years, because results from any one site or year would likely have mischaracterized the spatial and temporal distribution of this common salt marsh consumer.

Contributors Tianjiao Adams, Huy Vu and Steven C. Pennings

Adams, T., Vu, H. and Pennings, S.C. 2022. Variation in Densities of the Salt Marsh Katydid Orchelimum fidicinium over Space and Time. Estuaries and Coasts. 45:260-271. (DOI:

Key Words grasshopper, insect, Orchelimum, population dynamics, SINERR Publication, Student Publication, UGAMI Publication
File Date 2022
Web Link Web link
view/download Web link

This material is based upon work supported by the National Science Foundation under grants OCE-9982133, OCE-0620959, OCE-1237140 and OCE-1832178. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.