Population size and dispersal patterns for a Drimeotus (Coleoptera, Leiodidae, Leptodirini) cave population

Trypodendronlineatum (Olivier) and Gnathotrichussulcatus (LeConte) beetles (Coleoptera: Scolytidae) were marked with fluorescent powder and released in a sawmill area during a pheromone-based mass trapping program for ambrosia beetles. Trapping efficiency was estimated at 5.9% for T. lineatum and 5.5% for G. sulcatus. This technique had good potential for obtaining information on trapping efficiency, population size, and beetle dispersal patterns. Suggestions are given for improving the accuracy of the information obtained and for additional uses of mark-recapture in evaluating and optimizing mass trapping programs for ambrosia beetles.

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Insights into The Dispersal Patterns of Yellow-Footed Rock-wallabies, Petrogale xanthopus.

Australian Mammalogy ◽

10.1071/am97229 ◽

1996 ◽

Vol 19 (2) ◽

pp. 229

Author(s):

A. Sharp

Keyword(s):

Population Size ◽

Resource Availability ◽

Radio Telemetry ◽

Juvenile Male ◽

Dispersal Patterns ◽

Social Hierarchies ◽

Large Colony ◽

The Social ◽

Low Levels ◽

Low Rate

Inter-colony and within-colony dispersal was monitored in a large colony of P. xanthopus (central-western Queensland) for a period of 34 months, utilising radio-telemetry and regular surveys for tagged individuals. Trap shyness limited the collection of information on juvenile wallabies (n=15). Of the 120 wallabies monitored, only one juvenile male was found to undertake inter-colony dispersal (0.8%). Movement of wallabies between groups within the colony was relatively high (29%), with the majority of movement undertaken by males (21%). Evidence was found that suggests a relationship between the timing of inter-group dispersal and the availability of positions within the social hierarchies of adjacent groups. No relationships were found between the timing of inter-group dispersal and population size or levels of resource availability. In a meta-population context, the low levels of inter-colony dispersal detected in this study suggest that colonies in decline will receive little input of individuals from outside sources and that the establishment of new colonies may occur at a low rate.

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Reduction of spermatogonia and testosterone in rat testes flown on space lab-3

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142864 ◽

1986 ◽

Vol 44 ◽

pp. 248-249

Author(s):

Delbert E. Philpott ◽

W. Sapp ◽

C. Williams ◽

T. Fast ◽

J. Stevenson ◽

...

Keyword(s):

Social Interaction ◽

Social Status ◽

Population Size ◽

Physiological Response ◽

Social Rank ◽

Reproductive Function ◽

Testicular Development ◽

Organ Weights ◽

Reproductive Maturation ◽

Metabolic Activities

Space Lab 3 (SL-3) was flown on Shuttle Challenger providing an opportunity to measure the effect of spaceflight on rat testes. Cannon developed the idea that organisms react to unfavorable conditions with highly integrated metabolic activities. Selye summarized the manifestations of physiological response to nonspecific stress and he pointed out that atrophy of the gonads always occurred. Many papers have been published showing the effects of social interaction, crowding, peck order and confinement. Flickinger showed delayed testicular development in subordinate roosters influenced by group numbers, social rank and social status. Christian reported increasing population size in mice resulted in adrenal hypertrophy, inhibition of reproductive maturation and loss of reproductive function in adults. Sex organ weights also declined. Two male dogs were flown on Cosmos 110 for 22 days. Fedorova reported an increase of 30 to 70% atypical spermatozoa consisting of tail curling and/or the absence of a tail.

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