Reproduction during Two Annual Cycles in a Population of Peromyscus leucopus noveboracensis

1976 ◽  
Vol 57 (3) ◽  
pp. 593-595 ◽  
Author(s):  
D. L. Rintamaa ◽  
P. A. Mazur ◽  
S. H. Vessey
1994 ◽  
Vol 30 (10) ◽  
pp. 161-171 ◽  
Author(s):  
A. J. Theodorou

Nutrient pollution in Elefsis Bay arises mainly from the disposal of Athens untreated wastewater at the eastern entrance of the Bay. The absence of river discharge, lack of cultivated agricultural areas providing runoff and the Bay's limited circulation provide the conditions for the Bay's eutrophication by the discharge of untreated wastewater. In the spring of 1993 this discharge was replaced by a new deep outfall system. To monitor any future changes an assessment of the present ecological state of the Bay is required. Analysis of appropriate data showed that Elefsis Bay accumulates nutrients. In summer a strong thermal stratification causes anoxic conditions to occur in the lower layer. The ecosystem exhibits reduced species diversity and strong oscillations of plankton annual cycles. Flagellates (Cryptomonas sp.) dominate the phytoplankton, followed by dinoflagellates (Gyrodinium aureolum, Prorocentum dentatum) and only in the spring diatoms (Nitzschia) predominate. The zooplankton was dominated by copepods (Acartia clausi) and cladoceran (Podon polyphemoides). Macrobenthos consists of a small number of pollution-resistant species of Polychaeta (Capitela capitata), whilst in summer only one species of Molluscs (Corbula gibba) survives.


The Condor ◽  
2001 ◽  
Vol 103 (1) ◽  
pp. 180-183 ◽  
Author(s):  
Thomas J. Maier ◽  
Richard M. Degraaf

Abstract Small mammals, such as mice and voles, have been implicated as major egg predators of Neotropical migrant passerines by field studies using soft plasticine eggs or the very small eggs of Zebra Finch (Taeniopygia guttata). Nevertheless, the effort required to depredate these commonly used egg surrogates may be less than that required to depredate the larger, thicker-shelled eggs of most passerine species. To compare the depredation of these surrogates to that of the eggs of a mid-sized passerine by a ubiquitous small predator, we exposed dissimilar pairs of plasticine, Zebra Finch, and House Sparrow (Passer domesticus) eggs to captive white-footed mice (Peromyscus leucopus). Plasticine eggs were marked by mice more than either kind of real egg, and Zebra Finch eggs were breached more often than House Sparrow eggs. We conclude that the use of either plasticine or Zebra Finch eggs may lead to overestimation of the ability or proclivity of small mammals to actually depredate the eggs of most passerines.


1998 ◽  
Vol 7 (3‐4) ◽  
pp. 258-264 ◽  
Author(s):  
HUIWANG GAO ◽  
SHIZUO FENG ◽  
YUPING GUAN

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