Nestmate discrimination in social wasps (Polistes metricus,Hymenoptera: Vespidae)

Summary Laboratory-overwintered paper wasp (Polistes metricus) females preferentially associate on new nests with former nestmates (presumably their sisters) rather than with non-nestmates in the absence of cues associated with their natal nests or nest sites. Females isolated from conspecifics and nests for 74–99 days retain the ability to discriminate nestmates from nonnestmates.     

WATER AS A COMMODITY IN INTERNATIONAL TRADE1

International trade in water has been pioneered by coastal or island city-states, by areas subject to boundary revision after a water supply system had been established, by informal accommodations among good neighbors, and by co-riparians agreeing to negotiate on compensation as an element in water allocation. Specific examples are described. Formulations of criteria for an equitable agreement for possible transfers of Canadian water to the United States have been published by Laycock and by Kuiper. Many other Canadians have expressed serious concern over the long-range implications of water export and have frequently proposed restrictions which they believe that Canada should insist upon in any negotiations. Explicitly or implicitly in nearly all Canadian discussion of water export is the conviction that international transfer, should it be permitted at all, should occur at some mutually satisfactory point or points on the border with all questions or sources and routes within Canada being left to the agencies within Canada selected by the Canadians for the task.     

Trace analysis for aromatic hydrocarbons in natural waters

A method for trace analysis of volatile aromatic hydrocarbons in natural water is described. The method is based on sparging water samples with nitrogen, adsorption of hydrocarbons on activated charcoal, followed by desorption into carbon disulfide and gas chromatographic analysis. The sensitivity of the method reaches into the 0.1 to 0.2 μg/L concentration range for individual aromatic hydrocarbons. The accuracy and reliability of the method was validated. The method was used in three field studies: dispersion of aromatic hydrocarbons discharged from the Trans-Alaska Pipeline southern terminal throughout Port Valdez; survey of the Atigun River Watershed after oil spill on June 10, 1979; and chemical characterization of treated effluents from offshore oil extraction platforms in the Gulf of Mexico.