Bluegill (Lepomis macrochirus) and pumpkinseed (L. gibbosus) sunfish are sympatric over most of the Great Lakes basin and various studies have been car- ried out on the habitat and resource partition- ing of the older age...
Lateral-body bar marking differences can be used for identifying young-of-year bluegills and pumpkinseeds. The young-of-year of both species were reared in the laboratory from eggs and examined weekly for lateral-body bar pigmentation development. Pumpkinseeds were found to develop spots between...
The reproductive behavior of rock bass in Lake Opinicon begins with an abrupt movement of mature males to inshore nesting areas. Inshore density increases several fold and males become territorial, defending a bottom area in which they construct a nest...
The ears of moths we tested in Canada and CSte d'Ivoire are most sensitive to sounds between 20 and 40 kHz, and much less sensitive to sound over 65 kHz. The insectivorous bats most commonly encountered in these (and other)...
Analysis of the fish faunas of Lake Opinicon and other small, cold temperate Ontario water bodies shows that the component species differ in body size, morphology, abundances, habitats, diurnal and seasonal habitat utilization patterns, diets, dietary changes with age, reproductive...
Results of a survey of the submerged aquatic macrophytes in 16 sites in southeastern Ontario varying widely in geology and nutrient status are presented. Where comparisons could be made, species were generally found within the same range of specific conductivities...
The effect of the insecticide methoxychlor (2,2-bis(p-methoxyphenyl)-1,1,1-trichloroethane) on photosynthetic carbon assimilation by natural phytoplankton populations was determined by incubation of plankton samples in situ at a 1.0-metre depth with [14C]bicarbonate for 4-h periods with or without...
Garbage dumps are at present unavoidable and have considerable impact on areas where they are located. Darlington (1969) reviewed some of the potential effects of dumps, including the inhibition of plant growth by altering soil composition and permeability, and by...
Aggression to model brown-headed cowbirds measured at nests of 34 potential host species shows a positive correlation with rate of parasitism. The data are used to test two hypotheses: (1) that aggression functions as an antiparasite defense reducing parasitism, and...
On clear days the temperature in a mat of floating Lemnaceae was 40 to 11° above that of the surface of the open water. The temperature of the environment 2 cm above or below the plant surface closely followed the...
Structure in the aerial-feeding bat faunas of southeastern Ontario, southern British Columbia, Cameroun, Guyana, and the Philippines is demonstrated on the basis of wing shape and relative ear size. The former is derived from the ratio of the length of...
In equilibrated metamorphic rocks containing coexisting garnet, cordierite, quartz and sillimanite, the exchange of iron and magnesium between cordierite and garnet offers a highly favourable geological thermometer and barometer, because this exchange reaction is insensitive to pressure. Thermodynamic analysis shows...
The deciduous teeth of Myotis lucifugus and the sequence of their replacement by the permanent teeth are described. Juveniles possessing erupted adult dentitions were capable of flight and, for the first time, had insect remains in their digestive tracts.
The movements of P. leucopus in small island populations were studied by means of nightly smoked-paper tracking supple- mented by occasional livetrapping. The mice left enough track records on nights when trapped to show that they often do not enter...
