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In many ant species, nuptial flight tends to be short in time and assumed to be synchronous across a large area. Here, we
report that, in the upper Jordan Valley, northern Israel, massive nuptial flights of Carpenter ants (Camponotus sp.) occur frequently throughout the summer, and their alates form up to 90% of the diet of the greater mouse-tailed bat
(Rhinopoma microphyllum) during this period. This fat and protein-rich diet enables female bats to lactate during summer, and the large amount of
fat that both sexes accumulate may serve as an energy source for their following winter hibernation and posthibernation mating
in early spring (March–April). We suggest that the annual movement of these bats to the Mediterranean region of Israel may
have evolved in order to enable them to exploit the extremely nutritious forms of ant alates when the bats’ energetic demands
are highest. 相似文献
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MTBE (Methyl tert-Butyl Ether) is a fuel additive that replaced lead as an antiknock compound in internal combustion motors. Few years after its introduction, detectable levels of MTBE were found in various water bodies. MTBE has a very low taste and odor threshold and is a potential carcinogen. Another group of fuel derived toxic compounds that has been detected in water bodies is BTEX (Benzene, Toluene, Ethylbenzene and Xylene). Boating activity and allochthonous contributions from watersheds are the major sources of fuel derived pollutants in lakes. Their concentrations in lakes thus vary as a function of boating activity intensity, lake surface area and depth, weather and wind regime, land-use in the watershed, etc. The Sea of Galilee (Lake Kinneret) is the only recreational lake in Israel and an important freshwater source. In the current study, a sampling campaign was conducted in order to quantify MTBE and BTEX concentrations in Lake Kinneret, its marinas and its main contributing streams. In addition, a boating-use survey was performed in order to estimate MTBE and BTEX contribution of recreational boating. The sampling campaign revealed that, as expected, MTBE concentrations were higher than BTEX, and that near shore (i.e., marina) concentrations were higher than in-lake concentrations. Despite the clear contribution from boating, high MTBE concentrations were found following a major inflow event in winter, indicating the importance of the allochthonous contribution. The contribution from boating during summer, as measured indirectly by in-lake concentrations, is likely underestimated due to enhanced MTBE volatilization due to strong winds and high temperatures. May–September was found to be the main recreational boating season, with continued boating year round. On average, a single boat is active 23 d/y, with 84% of the watercrafts being active only during weekends and holidays. The survey further indicated that boats stay in the lake for 4.5 h on average, which conforms to the unique winds regime that limits afternoon activity due to high winds, and have an average fuel consumption of 14 L/h. The annual load of MTBE and BTEX from recreational boating in Lake Kinneret was estimated at 4430 and 6220 kg/y respectively. 相似文献
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The aim of this study was to compare two hot spots of lead (Pb) exposure in Israeli and Jordanian occupational settings. The study also sought to assess whether any differences in regulations and legislation regarding occupational health could be identified as a source of exposure disparities. Blood and hair specimens were collected from workers in a battery factory in Jordan and a secondary Pb smelter in Israel and compared. About 33% of the currently exposed group showed blood lead (BPb) levels above the internationally recommended concentration of 40 µg dL?1. Although the differences of BPb levels between Israel and Jordan were not statistically significant, average levels were lower in Jordan. Beyond the difference in the factory types, disparity in exposure levels might be explained due to a combination of proclivities of factory management, public policies, existing medical surveillance and insurance, as well as cultural differences. Results reveal that despite existing regulations and the growing attention that is dedicated to Pb and metal occupational exposures, there are still hot spots for Pb exposure in Israel and Jordan. The contrasting experience found in the current study raises the possibility that information and technology exchange between the two countries Israel and Jordan, may be beneficial for improving occupational health policy in these two neighboring countries. 相似文献
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