Influences of weather and time of day on trap catches of bush fly,Musca vetustissima Walker (Diptera: Muscidae)

1986 ◽  
Vol 76 (3) ◽  
pp. 359-366 ◽  
Author(s):  
W. G. Vogt

AbstractField populations of Musca vetustissima Walker were sampled in a region of New South Wales at 2-h intervals on 35 occasions between spring 1984 and autumn 1985 using wind-oriented fly traps. Ambient temperature, solar radiation, relative humidity and wind speed explained 84·3% of the within-day deviance of total catches (both sexes combined). Temperature and solar radiation jointly explained 82·6% of this deviance (71·1 and 11·5%, respectively), indicating that the other variables, although significant, did not greatly affect trap catches. As air temperature increased, log catch rates increased non-linearly up to a maximum at 27·5°C and declined thereafter. Log catch rates increased linearly as solar radiation increased and declined linearly as relative humidity and wind speed increased. Changes in log catch rates with time of day were explained almost entirely by the four weather variables, i.e. when weather effects were removed, time of day effects were no longer significant. These weather variables also accounted for 79·9% of the between-day variation in logarithms of trap catches. Relative responses of males and females to traps differed significantly with respect to relative humidity, wind speed and time of day. Male catches tended to increase relative to female catches between 1200 h and 1800 h and also declined more slowly with increases in relative humidity and wind speed. Separate models are presented for standardization of male and female catch rates; the estimates differ from those obtained from observed sex ratios and total catch rates, but the differences are small compared to the observed day-to-day variation in catch rates.

1983 ◽  
Vol 73 (4) ◽  
pp. 609-617 ◽  
Author(s):  
W. G. Vogt ◽  
T. L. Woodburn ◽  
R Morton ◽  
B. A. Ellem

AbstractField populations of Lucilia cuprina (Wied.) in New South Wales were sampled for periods of 3 h on numerous occasions between 1975 and 1982 using West Australian blowfly traps. Ambient temperature, wind speed, relative humidity and solar radiation explained 77·4% of the within-day deviance of the catches. Temperature alone accounted for 74·9% of this deviance, indicating that the other variables, although significant, did not greatly affect trap catches. As air temperatures increased, log catch rates increased linearly up to 26°C and then remained constant up to 35°C. Wind speeds above 25 m/s caused a linear decline in log catch rates. Log catch rates increased linearly as solar radiation increased and decreased linearly as relative humidity increased. Changes in catch rates with time of day were explained almost entirely by the four weather variables, i.e. there was no evidence that intrinsic behavioural changes with time of day affected catch rates. The combined effects of the four weather variables accounted for 47·1 % of the between-day variation in trap catches. Trap catches that have been standardised, i.e. adjusted to a ‘ standard’ set of weather conditions, provide relative measures of population size which differ from absolute measures by a constant (unknown) scaling factor.


1985 ◽  
Vol 75 (2) ◽  
pp. 315-320 ◽  
Author(s):  
W. G. Vogt ◽  
T. L. Woodburn ◽  
R. Morton ◽  
B. A. Ellem

AbstractDifferences in responses of males and females of Lucilia cuprina (Wiedemann) to carrion-baited traps were examined in Australia in relation to time of day, temperature, wind speed, relative humidity and solar radiation. The differences were small compared with responses obtained for the combined sexes (total catch), but the results were inconsistent over the four seasons of trapping. The seasons with most data (1975–1976 and 1981–1982) gave reasonably consistent results. Seasonal differences, although significant, were small enough to neglect for the purpose of standardizing trap catches. Time-of-day effects were also unimportant, except that males tended to be less active than females during the early morning (dawn-0900 h) and more active than females during the late afternoon (1500 h-dusk). Separate models are presented for standardization of male and female catch rates; the estimates differ from those obtained from total catches, but the differences are small compared to the observed day-to-day variation in catch rates.


2020 ◽  
Author(s):  
Kousik Das ◽  
Nilanjana Das Chatterjee

AbstractThe present study presents a view on exploring the relationship pattern between COVID 19 daily cases with weather parameters and air pollutants in mainland India. We consider mean temperature, relative humidity, solar radiation, rainfall, wind speed, PM2.5, PM10, SO2, NO2 and CO as independent variable and daily COVID 19 cases as dependent variable for 18 states during 18th march to 30th April, 2020.After dividing the dataset for 0 to 10 day, 10 to 25 days and 0 to 44 days, the current study applied Akaike s Information Criteria (AIC) and Generalized Additive Model (GAM) to examine the kind of relationship between independent variables with COVID 19 cases. Initially GAM model result shows variables like temperature and solar radiation has positive relation (p<0.05) in 0 to 10 days study with daily cases. In 25 days dataset it significantly shows that temperature has positive relation above 23 degree centigrade, SO2 has a negative relationship and relative humidity has negative (between 30% to 45% and > 60%) and a positive relationship (45% to 60%) with COVID 19 cases (p=0.05). 44 days dataset has six parameters includes temperature as positive, relative humidity as negative (between 0 to 45%) and then positive (after >45%), NO2 as Positive (0 to 35 microgram/m3) followed by negative trend (after > 40 microgram/m3), SO2 and rainfall as negative relation. After sensitive analysis, it is found that weather variables like relative humidity, solar radiation and rainfall are more sensitive than temperature and wind speed. Whereas pollutants like NO2, PM2.5, PM10 and CO are more sensitive variables than SO2 in this study. In summary this study finds temperature, relative humidity, solar radiation, wind speed, SO2, PM2.5, and CO may be important factors associated with COVID 19 pandemic.Graphical AbstractHighlights➢There was a significant relationship between daily positive COVID-19 case with weather and pollution factors➢We found PM2.5 and CO positively associated with transmission of positive cases where as NO2 and SO2 have a negative relation after sensitive analysis.➢We have found temperature and wind speed have positive relation whereas, relative humidity and solar radiation have negative relation after sensitive analysis.➢Weather variables like relative humidity and solar radiation and rainfall are more sensitive than temperature and wind speed. Pollutants like NO2, PM2.5, PM10 and CO are more sensitive variables than SO2 in this study.


1999 ◽  
Vol 26 (5) ◽  
pp. 675 ◽  
Author(s):  
P. B. Whitaker ◽  
R. Shine

Encounters between humans and dangerously venomous snakes put both participants at serious risk, so the determinants of such encounters warrant attention. Pseudonaja textilis is a large fast-moving elapid snake responsible for most snakebite fatalities in Australia. As part of a broad ecological study of this species in agricultural land near Leeton, New South Wales, we set out to identify factors influencing the probability that a human walking in farmland would come into close proximity to a brownsnake. Over a three-year period, we walked regular transects to quantify the number and rate of snake encounters, and the proportion of snakes above ground that could be seen. The rate of encounters depended upon a series of factors, including season, time of day, habitat type, weather conditions (wind and air temperature) and shade (light v. dark) of the observers’ clothing. Interactions between factors were also important: for example, the effect of air temperature on encounter probability differed with season and snake gender, and the effect of the observers’ shade of clothing differed with cloud cover. Remarkably, even a highly-experienced observer actually saw <25% of the telemetrically monitored snakes that were known to be active (i.e. above ground) nearby. This result reflects the snakes’ ability to evade people and to escape detection, even in the flat and sparsely vegetated study area. The proportion of snakes that were visible was influenced by the same kinds of factors as described above. Most of the factors biasing encounter rates are readily interpretable from information on other facets of the species’ ecology, and knowledge of these factors may facilitate safer coexistence between snakes and people.


1993 ◽  
Vol 20 (6) ◽  
pp. 785 ◽  
Author(s):  
DM Watson ◽  
TJ Dawson

The effects of temporal (time of day and season) factors and size, sex, female reproductive state and group size on the diel time-use of free-ranging red kangaroos (Macropus rufus) was examined. Particular emphasis was given to the effects on their foraging behaviour, with foraging divided into cropping, chewing and searching components. The study was conducted in semi-arid western New South Wales from July 1991 to March 1992, a time of deepening drought conditions in New South Wales. Group size had very little influence on the time-use of M. rufus. It was negatively but only weakly correlated with the proportion of foraging time spent chewing (chewing intensity). No significant differences in time-use were found between size classes of adult males (large and medium-sized males), females with or without pouch young, or females with different-sized pouch young (no visible young, small pouch young or large pouch young). Differences occurred between adult males, adult females and subadult kangaroos. These differences were mainly associated with their chewing and searching behaviour and were related to body size; as body size increased the proportion of time spent chewing and the intensity of chewing increased while the proportion of time searching and the proportion of foraging time spent searching (searching intensity) decreased. Neither the proportion of time spent cropping or foraging nor the proportion of foraging time spent cropping (cropping intensity) or the proportion of active time spent foraging (foraging intensity) differed between any size/sex/reproductive class. Temporal effects had a considerable influence on time-use. M. rufus were most active at night and in the few hours after sunrise and sunset. Seasonal changes in time-use were largely a result of changes in daytime behaviour. M. rufus foraged less and rested more during the day in winter than in spring or summer. There was no increase in the intensity or proportion of time spent foraging or cropping at night to compensate for the reduction in diurnal foraging. It is hypothesised that temporal variations in time-use were related to variations in weather and vegetation conditions.


1992 ◽  
Vol 40 (3) ◽  
pp. 279 ◽  
Author(s):  
IR Wallis ◽  
B Green

Water flux and field metabolic rate (FMR) were measured by the doubly labelled water (DLW) method in free-living male and female rufous rat-kangaroos Aepyprymnus rufescens near Drake in northern New South Wales. The mean FMR of 499 kJ kg-1 day-1 was similar in winter and summer even though the difference in mean minimum temperatures between the two seasons was 20-degrees-C. Furthermore, we did not find any differences in FMR between males and females even though several females carried large pouch young or had young-at-foot. A poor understanding of the diet and the behavioural ecology of A. rufescens makes ft difficult to explain the similarities between sexes and seasons.


1984 ◽  
Vol 26 (2) ◽  
pp. 194-208 ◽  
Author(s):  
P. C. Gregg ◽  
G. C. Webb ◽  
M. A. Adena

The B chromosomes of Chortoicetes terminifera possess an accumulation mechanism. B chromosomes were transmitted at a rate of 0.766 in one B(♂) × zero B(♀) crosses and 0.477 in zero B(♂) one × B(♀) crosses. In crosses where the female had a B chromosome, there were significant differences in transmission rates between pods, but these were not related to differences in G-banding patterns of the B chromosomes involved. In crosses where either the male or female parent had two B chromosomes the B chromosomes did not segregate perfectly, nor did they segregate in a random fashion. The closest resemblance to the behaviour of normal bivalents occurred when the two B chromosomes were of the same, rather than different, G-banding variants, and when they were present in the male rather than the female parent. B chromosomes occurred at eight localities scattered throughout New South Wales. No locality was found where they were not present. The average frequency of B chromosomes was 14.0% for one-B individuals and 0.8% for two-B individuals. There were no significant differences in B-chromosome frequency between males and females. Of the eight localities, only one had a B-chromosome frequency significantly different from any other locality. This relatively uniformity of B-chromosome distribution is interpreted as a consequence of the migratory nature of C. terminifera. A model was constructed to simulate the dynamics of B chromosomes in locust populations. Three main dynamic patterns were recognized, and these were related to differences in the fitness of one-B and two-B individuals. It was concluded that the B chromosome of C. terminifera is probably parasitic, although the simulation model revealed some difficulties which suggest that caution should be applied to the description of any B chromosome as purely parasitic.Key words: B chromosomes, locust, meiotic drive, G-banding, fitness. Chortoicetes terminifera (Walker).


Zootaxa ◽  
2006 ◽  
Vol 1304 (1) ◽  
pp. 1 ◽  
Author(s):  
VOLKER W. FRAMENAU

The wolf spider genus Anomalosa Roewer, 1960 is revised with Anomalosa kochi (Simon, 1898) as type species. Anomalosa includes a further Australian species, A. oz sp. nov. Representatives of Anomalosa are small, elongated lycosids with a longitudinal light median band on the dorsal shield of the prosoma and on the opisthosoma, the latter being particularly distinct in males. They are closely related to Venonia Thorell, 1894. Similar to Venonia, males have a bipartite prolateral tegular lobe on the pedipalp, but it is much larger than in Venonia and, in contrast to Venonia, larger than the membranous tegular apophysis. Anomalosa kochi has only been found in Queensland, whereas the distribution of A. oz sp. nov. includes New South Wales, South Australia and Victoria. This allopatric distribution coincides with the McPherson Range as a biogeographical border. Although most males and females of Anomalosa have been caught in pitfall traps or running freely in moderately moist habitats, such as near creeks and dams, there is evidence that representatives of this genus build sheet-webs similar to Venonia. This behaviour is supported by morphological evidence as species of Anomalosa have elongated posterior spinnerets. The original description of A. harishi (Dyal, 1935) from Panjab, India, does not match the diagnosis of Anomalosa. Consequently, I reject the inclusion of A. harishi in Anomalosa and re-transfer it to its original genus Anomalomma Simon, 1890, Anomalomma harishi Dyal, 1935, pending a systematic revision of this genus.


1978 ◽  
Vol 29 (2) ◽  
pp. 359
Author(s):  
R Barlow ◽  
EB Dettmann ◽  
LG Williams

Weaning weight (ww) and conformation score (cs) records from Angus calves in five New South Wales herds were analysed by least-squares procedures to assess the nature and magnitude of variation. Herd, year, age of dam and sex were considered as main effects. Covariates included in the models were weaning age (WA) for ww and average daily gain (ADG), and both WA and ww for cs. Male calves (steers and bulls) were 16.6 kg heavier at weaning than female calves. Dams that were 5-8 years of age weaned calves that were 30.1 kg, 15.4 kg and 6.7 kg heavier than 2-, 3- and 4-year-old dams respectively. When ww was not included as a covariate in the model, age of dam effects on cs reflected those on ww, and there was little difference in cs between males and females. When adjusted for differences in ww, males had poorer cs than females, and calves from 3-year-old dams, and from dams over 8 years old, had poorer cs than those from dams of all other ages. Partial regressions of ww and ADG on WA, and of cs on ww, varied considerably between herd/year/sex subgroups.


1981 ◽  
Vol 71 (2) ◽  
pp. 207-225 ◽  
Author(s):  
R. Morton ◽  
L. D. Tuart ◽  
K. G. Wardhaugh

AbstractHourly and nightly catches of Heliothis armiger (Hb.) and H. punctiger Wllgr. at a site adjacent to 2000 ha of commercial cotton in the Namoi Valley of New South Wales, were analysed in relation to various environmental factors and showed that wind speed, temperature, night-length and (H. armiger only) moonlight exerted a significant influence on trap-catch. For H. punctiger and H. armiger respectively, these factors accounted for 80 and 60% of the deviance in hourly catches but only 70 and 40% of the variation in nightly catches. Wind speeds of more than 1·7 m/s suppressed the catch of both species but had a greater effect on H. punctiger than H. armiger. Whereas with both species, the optimum temperature for trapping was about 27°C, temperature had a greater influence on the catch of H. punctiger than of H. armiger. Bright moonlight was estimated to reduce the catch of H. armiger by 49%, but no significant effect was detected for H. punctiger. The analysis revealed a number of occasions for both species in which the hourly distribution of catch and/or the change in catch between successive nights was aberrant. With H. armiger, these inconsistencies appeared to be associated with changes in population due to adult emergence, whereas for H. punctiger the most likely cause seemed to be changes due to movement. The combined effects of wind speed, temperature, night-length and moonlight were used to adjust the nightly catches of each species according to the environmental conditions prevailing on a ‘ standard’ night. This was defined as a typical summer's night with temperatures decreasing from 28·8°C at dusk to 20·6°C at dawn and ideal catching conditions, i.e. no moon and wind speed never exceeding 1·7 m/s. As such, the adjusted catches could be taken as indices of moth abundance. These showed that H. armiger had three discrete periods of abundance, characterised by the presence of large numbers of young moths and spaced at intervals suggesting successive generations. A similar pattern was lacking in H. punctiger, which was abundant only during the first half of the season. Except during periods of emergence (H.armiger), or once when spraying occured during daylight, the aerial application of insecticides to the cotton adjecent to the light-trap resulted in marked reductions in the populations of both species.


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