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Wildlife managers in northwestern Colorado have had difficulty accurately estimating numbers of subadult male elk (Cervus elaphus) by sampling winter population densities and sex ratios. We investigated emigration and survival of telemetered 2-year-old male elk in a trophy hunting area in a northwestern Colorado Game Management Unit (GMU) to evaluate management strategies. We hypothesized that skewed numbers of males resulted from high subadult mortality or dispersal of subadult males. We used telemetered elk and Kaplan-Meier staggered entry methods to estimate emigration probability of 0.56 and 0.33 in 1995 and 1996, respectively. Maximum distances moved by emigrants from their capture point averaged 87 km (median...
Bryophytes disperse by small unicellular spores between 7 ?m und usually less than 100 ?m. A large percentage of species is sterile and propagates vegetatively either by special brood bodies or fragments of whole plants. It is shown that there is no difference in the effectiveness between generative and vegetative propagation. Size and weight of the diaspores suggest that both must easily be dispersed and the species must therefore have wide ranges. This does, however, not result in ubiquitous occurrence. This is only true for part of the species. Many, even sterile species show wide transcontinental ranges. On the other hand, there are many examples of limited to very limited distribution in spite of a rich production...