Individual foraging components of harvester ants: movement patterns and seed patch fidelity

SummaryWe investigated individual foraging components of the western harvester ant,Pogonomyrmex occidentalis, in the native seed background of a shrub-steppe environment. Our study identified factors affecting foraging movements and seed selection by individual ants. Some assumptions and predictions of central-place foraging theory and a correlated random walk were evaluated for individual foragers. Results showed that ant size was only weakly correlated with the seed sizes harvested; seed size was a more important constraint than a predictor of seed selection. Individual ants spent more time in localized search behavior than traveling between search areas and nests.P. occidentalis foragers encountered seeds randomly with respect to time, and handled a mean of 1.7 seeds/trip. A correlation of increased search effort with greater travel distances was consistent with central-place foraging theory but, contrary to it, search and travel effort were not associated with energetic reward.Individual ants exhibited fidelity in both search site and native seed species. Spatial analyses of foraging movements showed a highly oriented travel path while running, and an area-restricted path while searching. Searching ants moved in a manner consistent with a correlated random walk. The deterministic component of patch fidelity and the stochastic component of search may override energetic foraging decisions in individualP. occidentalis ants.

[1]  Edward O. Wilson,et al.  Recruitment Trails in the Harvester Ant Pogonomyrmex Badius , 1970 .

[2]  John A. Nelder,et al.  Statistics In Biology. , 1971 .

[3]  L. Rogers.  Foraging Activity of the Western Harvester Ant in the Shortgrass Plains Ecosystem , 1974 .

[4]  R. Bernstein,et al.  FORAGING STRATEGIES OF ANTS IN RESPONSE TO VARIABLE FOOD DENSITY , 1975 .

[5]  E. Wilson,et al.  Caste and ecology in the social insects. , 1979, Monographs in population biology.

[6]  J. D. Vita.  Mechanisms of Interference and Foraging Among Colonies of the Harvester ant Pogonomyrmex Californicus in the Mojave Desert , 1979 .

[7]  E. Batschelet.  Circular statistics in biology , 1981 .

[8]  J. Herbers,et al.  Reliability theory and foraging by ants , 1981 .

[9]  B. J. Macauley,et al.  Food collection within an ant community in semi-arid Australia, with special reference to seed harvesters , 1981 .

[10]  S. Rissing.  Foraging Velocity of Seed-Harvester Ants, Veromessor pergandei (Hymenoptera: Formicidae) , 1982 .

[11]  S. Porter,et al.  Foraging Behavior of Pogonomyrmex owyheei in Southeast Idaho , 1982 .

[12]  FORAGING BEHAVIOR OF THE HARVESTER ANT MESSOR ACICULATUS IN RELATION TO THE AMOUNT AND DISTRIBUTION OF FOOD , 1982 .

[13]  R. Wehner,et al.  Foraging strategies in individually searching ants, Cataglyphis bicolor (Hymenoptera: Formicidae) , 1983 .

[14]  R. D. Harkness,et al.  Central place foraging by an ant (Cataglyphis bicolor Fab.): a model of searching , 1985, Animal Behaviour.

[15]  J. Deneubourg,et al.  From individual to collective behavior in social insects , 1987 .

[16]  O. Reichman,et al.  Distribution of Seeds in Sonoran Desert Soils: Implications for Heteromyid Rodent Foraging. , 1987, Ecology.

[17]  R. Wehner.  Spatial organization of foraging behavior in individually searching desert ants, Cataglyphis (Sahara Desert) and Ocymyrmex (Namib Desert) , 1987 .

[18]  Joaquin L Reyes Lopez.  Optimal Foraging in Seed-Harvester Ants: Computer-Aided Simulation. , 1987, Ecology.

[19]  C. McCulloch,et al.  Analyzing Discrete Movement Data as a Correlated Random Walk , 1989 .

[20]  Michael L. Cain,et al.  THE ANALYSIS OF ANGULAR DATA IN ECOLOGICAL FIELD STUDIES , 1989 .

[21]  J. Traniello.  Foraging Strategies of Ants , 1989 .

[22]  James A. MacMahon,et al.  Foraging Patterns of Pogonomyrmex occidentalis (Hymenoptera: Formicidae) in a Shrub–Steppe Ecosystem: The Roles of Temperature, Trunk Trails, and Seed Resources , 1991 .

[23]  U. Maschwitz,et al.  Foraging strategies and recruitment behaviour in the European harvester ant Messor rufitarsis (F.) , 1985, Oecologia.

[24]  Diane W. Davidson.  Experimental tests of the optimal diet in two social insects , 2004, Behavioral Ecology and Sociobiology.

[25]  S. Rissing.  Foraging specializations of individual seed-harvester ants , 1981, Behavioral Ecology and Sociobiology.

[26]  P. Kareiva,et al.  Analyzing insect movement as a correlated random walk , 1983, Oecologia.

[27]  F. Taylor.  Foraging behavior of ants: Experiments with two species of myrmecine ants , 1977, Behavioral Ecology and Sociobiology.

[28]  J. Fewell.  Directional fidelity as a foraging constraint in the western harvester ant, Pogonomyrmex occidentalis , 2004, Oecologia.

[29]  B. Hölldobler.  Recruitment behavior, home range orientation and territoriality in harvester ants, Pogonomyrmex , 1976, Behavioral Ecology and Sociobiology.

[30]  S. Rissing,et al.  Worker size variability and foraging efficiency in Veromessor pergandei (Hymenoptera: Formicidae) , 1984, Behavioral Ecology and Sociobiology.

[31]  Robert R. Parmenter,et al.  Factors determining the abundance and distribution of rodents in a shrub-steppe ecosystem: the role of shrubs , 1983, Oecologia.

[32]  J. Macmahon,et al.  Native seed preferences of shrub-steppe rodents, birds and ants: the relationships of seed attributes and seed use , 1986, Oecologia.

[33]  J. Fewell.  Energetic and time costs of foraging in harvester ants, Pogonomyrmex occidentalis , 1988, Behavioral Ecology and Sociobiology.

[34]  R. Hobbs.  Harvester ant foraging and plant species distribution in annual grassland , 1985, Oecologia.

[35]  J. Deneubourg,et al.  The self-organizing exploratory pattern of the argentine ant , 1990, Journal of Insect Behavior.

[36]  D. Fresneau,et al.  Individual foraging and path fidelity in a ponerine ant , 1985, Insectes Sociaux.

[37]  D. Gordon.  Species-specific patterns in the social activities of harvester ant colonies (Pogonomyrmex) , 1984, Insectes Sociaux.