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Rainfall is often indirectly related to the availability of resources, which in turn regulates the abundance of rodents over time. However, the direct influence of rainfall on daily activity is poorly understood, despite the fact that it likely has a great effect on small animals. Furthermore, the influence of the moon on the movement of rodents has been the subject of debate but limited to studies conducted in open areas. Based on a study using pitfall traps in a subtropical region of southern Brazil, this study aimed to investigate the effects of rainfall and the phases of the moon on the daily movements of five species of sigmodontine rodents in a Neotropical forest. Activity patterns were assessed over 130 days, and the daily rainfall and moon phase were verified. Rainfall exhibited a significant positive effect on all studied species. This reflects an increase in the movement of rodents on rainy days, which should be primarily associated with the immediate harmful effects of rain, such as a wet coat and the destruction of shelters. The five species responded differently to moon phase, with a lack of effect for three of them and a positive effect of a full moon on the activity patterns of the other two species. This increase in activity rhythm due to a full moon may indicate a benefit of clear nights for foraging, in contrast to the most common outcome, which associates the brightness of the moon with increased predation risk.
Little is known about the spatial ecology and ranging behaviour of vultures in Europe. In this paper we used GPS satellite telemetry to assess home-ranges of eight non-breeding Eurasian Griffon Vultures in Spain, trying to answer the main questions on when (i.e. the time of the day), how far (i.e. hourly and daily distances) and where vultures range (i.e. home-range size). Results indicated that vultures ranged extensively mainly in areas where traditional stock-raising practices and pasturing were still common, also including some vulture restaurants, which were visited occasionally. Eurasian Griffon Vultures concentrated their hourly and daily movements in the middle of the day, when the availability of thermal updrafts was higher, favouring foraging activities. The overall foraging range, calculated as Minimum Convex Polygon (MCP) (7419 km2), or as 95% and 50% kernel contours (4078 km2 and 489 km2, respectively), was higher than those reported in previous studies. The precise knowledge of the ranging behaviour and spatial parameters is particularly important for the conservation of scavenger species inhabiting human-dominated areas where human activities may jeopardize vulture populations in the long term.
Studies on the daily activity of A. lusitanicus were conducted under field and laboratory conditions. Two main phases - the activity phase and the phase of resting- have been distinguished in the daily cycle of the slug. The observed activity was of different types, such as crawling, feeding and the state of semiactivity. lt has been found that slug activity is determined by various atmospheric factors, mainly by light intensity, rainfalls and presence of dew. Slug activity is strongly influenced by their physiological 24 hr. life rhythm. Full activity was exhibited by all individuals after sunset and after the appearance of dew. They return to their shelters about three hours after sunrise. Feeding of A. lusitanicus, including periods of resting, lasts throughout the whole night, since their emergence from shelters until early morning hours. Most of the slugs start intensive feeding 2-3 hours after sunset.
A method was proposed for studying population density, microhabitat preference, daily activity and seasonal activity in small rodents. In this method, artificial tunnels (PVC pipes) imitating a natural system of burrows were applied. Their use by rodents was recorded by means of the electronic counters provided with a photoelectric cell. The study was conducted in an alder swamp 110 years old, located in the Kampinos National Park (52°25’N, 20°53’E) during 2003–2005. In this area, the bank vole Clethrionomys glareolus (Schreber, 1780) accounted for 90–99% of the captured rodents. The use of the tunnels by rodents (the number of passages) did not depend on their length within a range of 1–8 m applied in the experiment (P = 0.22). The tunnels were used by day and night, at the highest rate in the evening and at night. The use of tunnels increased when a bait was exposed in the vicinity (P = 0.001). It was positively correlated with population density (estimated with the CMR technique), and varied from season to season (in spring, summer, and autumn). The formula: density = 0.1717 + 0.0304 × mean number of passages per day, enabled the estimation of population density based on the number of passages through the tunnels. It has been found that a single tunnel was typically used by 5 individuals (mean 4.6 individuals, SD = 1.8). The location of tunnels had a significant effect on their use. Tunnels connecting fallen logs or bases of alders (hummocks) were more frequented than those leading to shrubby areas (P <0.000) or to microhabitats covered with herbaceous vegetation (P <0.001). This method enabled a multisided analysis of the behaviour of rodents at a minimum interference in the life of animals. Thanks to the application of electronic counters of passages, it was possible to obtain easily a large number of data. It is proposed to mark rodents with electronic transponders in the future studies to identify the individuals using artificial tunnels. This method could replace the methods used so far in the studies of small rodents, requiring trapping (CMR) or radio-telemetry.
This paper presents preliminary results of observations of circadian activities of one of the tested slug species – Arion lusitanicus. The study was conducted in laboratory conditions at two different temperatures 10 and 16ºC. The results showed that slugs were much more active at night than during the day. Most of the time during the day they spent in shelter, but little time devoted to nutrition. Arion lusitanicus slugs activity was significantly lower at 10 than at 16°C.
Factors affecting the population density and daily pattern of activity of the European ground squirrel Spermophilus citellus (Linnaeus, 1766) were studied in two habitats of the Kiskunsag National Park, Hungary. One habitat was dominated by sandy and the other by salty grassland. Population densities were estimated by counting ground squirrel burrow entrances in sample areas with different microhabitat characteristics. Three categories (elevated, level and depressed) were used to describe the spatial distribution of burrows according to microtopography. Daily activity was evaluated by counting the ground squirrels visible on the surface and registering their alarm calls. The highest proportion of ground squirrel holes was found on elevations in the two habitats. Ground squirrels showed a similar daily activity pattern in different areas and in the same season in consecutive years. The daily activity consisted in a morning peak, a midday pause and a less regular afternoon activity period. Human activity had no direct effect on the daily activity pattern. Emission of alarm calls peaked in June, when litters emerge from the maternal burrows.
The research was performed on sweet corn, Candle variety, in Terliczka near Rzeszow, in 2006–2009. In the period from the third decade of July to mid August, when the number of Diabrotica virgifera beetles was the highest, their daily activity on plants was observed at 6.00 a.m.; 9.00 a.m.; 12.00; 3.00 p.m. and 6.00 p.m. On the basis of performed research it was found that the activity of beetles D. virgifera is the highest at 9:00 a.m. and 6:00 p.m. Thus, observations of the beetles chemical control, as well as observations related to that pest’s presence in crops, should be performed at that time.
Research was performed on the activity of Heteroptera and Coleoptera in four water bodies in Olsztyn (Poland). In general, the majority of Coleoptera showed nocturnal activity. The majority of beetles were predatory. In the case of Heteroptera, there was only a small difference between diurnal and nocturnal activity.
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