Population Biology Commons^™

Larval Performance And Kill Rate Of Convergent Ladybird Beetles, Hippodamia Convergens, On Black Bean Aphids, Aphis Fabae, And Pea Aphids, Acyrthosiphon Pisum, Travis M. Hinkelman, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Generalist predator guilds play a prominent role in structuring insect communities and can contribute to limiting population sizes of insect pest species. A consequence of dietary breadth, particularly in predatory insects, is the inclusion of low-quality, or even toxic, prey items in the predator’s diet. Consumption of low-quality prey items reduces growth, development, and survival of predator larvae, thereby reducing the population sizes of generalist predators. The objective of this paper was to examine the effect of a suspected low-quality aphid species, Aphis fabae (Scopoli) (Hemiptera: Aphididae), on the larval performance of an abundant North American predator, Hippodamia convergens (Guérin-Méneville) …

Fifteen Years Of Colony Dynamics In Pogonomyrmex Occidentalis, The Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Ecological communities respond to environ- mental changes as the individuals of the component species die and are replaced. Thus, pat- terns of population turnover form an important aspect of community processes. Much less is known about species of long-lived individuals than of short-lived ones (Likens, 1989).

Instantaneous observations of age structure can be used to infer long-term dynamics but not all species can be aged retrospectively. Inferring life- history dynamics from current populations requires assumptions that are hard to verify. Following marked colonies of long-lived species is slow but provides direct, non-inferential data on population dynamics, although those are specific …

Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Little is known about the life span of individual ant colonies (Keeler, 1981), even though the dynamics of some species, such as harvester ants, are crucial to the structure of plant and animal communities (e.g., Brown et al., 1979). This note reports the results of 10 years of observations on a population of harvester ants.

Fifty-six mounds of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae), western harvester ant, were permanently marked with aluminum tags in August 1977. The site, about 1 ha just south of the University of Nebraska's Cedar Point Biological Station, Keith Co., Nebraska, was within a pasture subject to …

Preliminary Report Of Colony Survivorship In The Western Harvetser Ant (Pogonomyrmex Occidentalis) In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Colonies of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae) may live an average of 22 to 43 years. The population dynamics of individual colonies of P. occidentalis adjacent to the Univ. Nebraska's Cedar Point Biol. Sta., Keith Co., Nebraska, is the subject of an ongoing investigation. The habitat is a moderately grazed shortgrass prairie dominated by Bouteloua hirsuta, B. gracilis, and Buchloe dactyloides, with Stipa comata, Aristida spp., and various forbs. The colonies studied are in a triangular area about 400 m long and 100 m across at the widest point. The area appears to be at carrying …