Survival Rates for Northern Bobwhites on Two Areas with Different Levels of Harvest

We estimated survival rates for radio-marked northern bobwhites ( Colinus virginianus) in south-central Iowa from I 984 to I 988. Survival rates and survival functions were calculated for 2 areas that received different and varied amounts of hunting pressure. Survival from fall-spring averaged 17.1 % ± 6.9% on the Brown\u27s Slough study area (BSSA) and 20.1 % ± 5.7% on the Millerton study area (MSA). Although these estimates were not different (P = 0.898), the survival functions did differ between the 2 areas (x2 = 25.82, P\u3c0.001). Mortality due to hunting averaged 27.7% ± 8.2% on the BSSA during the fall-spring period and 12.3% ± 4.9% on the MSA. Predators accounted for 52% of fall-spring mortality on the BSSA and 79% of the mortality on the MSA. The BSSA had much lower rates of predation the 2 months following the hunting season. Survival rates during both the spring-fall period and annually did not differ between the 2 areas (P = 0.395 and P = 0.979). Hunting did not appear to be a limiting factor for quail numbers on these areas during the study

Survival Rates of Northern Bobwhite Chicks in South-Central Iowa

We estimated survival rates for radio-tagged northern bobwhite quail chicks (Colinus virginianus) in south-central Iowa from 1986 to 1988. Survival rates and survival functions were calculated for chicks from broods raised by females, broods raised by males and from broods that did not have an adult associated with them. Survival functions differed between broods with hens and those without adults. Predators accounted for almost all of the observed mortality

Breeding Strategies of the Northern Bobwhite in Marginal Habitat

We studied nesting behavior of radio-tagged northern bobwhite (Colinus virginianus) in south-central Iowa from 1984 to 1988. Female bobwhite incubated 78% of81 clutches where incubation was observed and males incubated 22%. On only 1 occasion were both a male and female observed to incubate the same clutch. Incubation was initiated on 73% of the nests by females before 1 July, while incubation was initiated on 56% of the clutches by males after 1 July. Males hatched 16% of all clutches, first nests by females accounted for 69%, renests for 4%, and second clutches by females that had already hatched 1 clutch for 11 %. Chicks from 3 of the first broods of females that hatched ~l brood survived for ~l week and were not accompanied by other adults. These breeding strategies appear to provide bobwhite populations multiple chances at recruitment in variable environments

Results of the August Roadside Survey for Upland Wildlife in Iowa: 1963-1988

Results of the August roadside survey collected from 1963 through 1988 were examined to determine if trends could be detected in the counts of ring-necked pheasants (Phasianus colchicus), northern bobwhite (Colinus virginianus), gray partridge (Perdix perdix), cottontail rabbits (Sylvilagus floridanus), and white-tailed jackrabbits (Lepus townsendii). The counts also were compared to harvest estimates co determine if correlations exist. Statistically significant linear trends were detected statewide for pheasants, gray partridge and jackrabbits during the 1963 co 1988 period. Trends were downward for all species except gray partridge. During the late 12 years (1977 through 1988), the only significant trend detected was for gray partridge, where counts increased. The survey results also were examined for trends on a regional basis where possible. Significant correlations were found between the mean counts and harvest for all species. For cottontails, however, chis relationship appears to have changed as the correlation of the counts with harvest since 1977 is near zero

Study of the pd→3HeK+K−pd\to ^3\textrm{He} K^+K^- and pd→3Heϕpd\to ^3\textrm{He} \phi reactions close to threshold

Two--kaon production in proton--deuteron collisions has been studied at three energies close to threshold using a calibrated magnetic spectrograph to measure the final $^3$He and a vertex detector to measure the $K^+K^-$ pair. Differential and total cross sections are presented for the production of $\phi$--mesons, decaying through $\phi\to K^+K^-$, as well as for prompt $K^+K^-$ production. The prompt production seems to follow phase space in both its differential distributions and in its energy dependence. The amplitude for the $pd\to ^3${He}$\phi$ reaction varies little for excess energies below 22 MeV and the value is consistent with that obtained from a threshold measurement. The angular distribution of the $K^+K^-$ decay pair shows that near threshold the $\phi$--mesons are dominantly produced with polarization $m=0$ along the initial proton direction. No conclusive evidence for $f_0(980)$ production is found in the data.Comment: 13 figure

Experimental study of the pd(d p) → 3 He ππ reactions close to threshold

New experimental data on the pd → 3 He π+π− reaction obtained with the COSY-MOMO detector below the three-pion threshold are presented. The reaction was also studied in inverse kinematics with a deuteron beam and the higher counting rates achieved were especially important at low excess energies. The comparison of these data with inclusive pd → 3 He X0 rates allowed estimates also to be made of π0π0 production. The results confirm our earlier findings that, close to threshold, there is no enhancement at low excitation energies in the π+π− system, where the data seem largely suppressed compared with phase space. Possible explanations for this behavior, such as strong p waves in the π+π− system or the influence of two-step processes, are explored

On a relation between particle size distribution and mixing layer height.

Ceilometers are applied to detect layering of the lower atmosphere continuously. This is necessary because not only wind speeds and directions but also atmospheric layering and especially the mixing layer height (MLH) influence exchange processes of ground level emissions. It will be discussed how the ceilometer monitoring information can be used to determine the MLH influence upon the particle size distribution (PSD) which is detected near the ground. The information about atmospheric layering is continuously monitored by uninterrupted remote sensing measurements with the Vaisala ceilometers LD40 and CL31 which are eye-safe commercial lidar systems. Special software for these ceilometers provides routine retrievals of lower atmosphere layering from vertical profiles of laser backscatter data. The meteorological data are collected by the air pollution monitoring station of the Bavarian State Agency of Environment (LfU) at the southern edge of Augsburg and at the airport at the northern edge of Augsburg by the German National Meteorological Service (DWD). PSD are measured at the aerosol measurement station in the centre of Augsburg by the Cooperative Health Research in the Region of Augsburg (KORA). The two intensive measurement periods during the winter 2006/2007 and 2007/2008 are studied. The weather situations are characterized, the meteorological influences upon air pollutant concentrations like wind speed and wind direction are studied and the correlations of ceilometer backscatter densities and MLH with PSD are determined