Seasonal Activity Peaks Research Articles

Seasonal activity of ixodid ticks in Podilskyi region

Ixodid ticks are the most important arthropod hematophagies in veterinary medicine. The spread of ticks and tick borne diseases is linked to human activities, including habitat change, deforestation, economic globalization, international animal movements, urbanization and climate change. The research was conducted from March 2018 to March 2019 in Khmelnytsky region. In total were collected 2086 D. reticulatus ticks and 658 I. ricinus ticks. During the studies, two peaks of seasonal activity of both species of ticks were observed according to the average number of specimens in the three study areas. Spring activity began in March, and the peak was observed in April. Males were found to be more active in March and the first half of April, while females dominated males from late May to late June. The second peak of activity in the study area began in mid-September. Since the beginning of September, the activity of ticks has increased almost eight times compared to August. The peak of autumn activity was observed in late October and early November. Active females dominated males from early October to late autumn. From mid-June to mid-September, single specimens of ticks were detected. During the winter, no ticks were found in the experimental plots. On average, in all experimental areas of Khmelnytsky region, ticks were active at a temperature of 10.8 to 27.8 °C (average temperature – 21.6 ± 6.57 °C) and humidity – 39.90–78.20 % (average humidity – 61.79 %). Statistical analysis performed for all study areas showed that air temperature significantly affected the activity of both species of ticks. However, correlations between the number of ticks collected and humidity throughout the study area and in different areas were not observed separately. The largest number of ticks was collected during the period when daylight lasted approximately 12–14 hours; in turn, the lowest number of ticks was detected on days with more than 15 hours of daylight. Statistical analysis confirmed the correlation between the length of daylight and the activity of ticks of both species.

Performance of Certain Mango Varieties to Infestation with The Plum Scale Insect, Parlatoria oleae (Colvee) (Hemiptera: Diaspididae) in Luxor Governorate, Egypt

Field experiments were conducted at a private mango orchard at Esna district, Luxor Governorate, Egypt during two successive years (2016/2017 and 2017/2018) to study the performance of some mango varieties to infestation with the plum scale insect, Parlatoria oleae (Colvee) (Hemiptera: Diaspididae). In this study, using different insect expressions, which articulated the population density of this pest. Two insect expressions were utilized, i.e., insect population and incidence of infestation. The obtained results showed that insect population of P. oleae occurred on all different mango varieties all the year round and has three peaks of seasonal activity per year, which was recorded in October, April, and July during the first year (2016/2017) and through in November, April, and July during the second year (2017/2018) in all tested mango varieties. Furthermore, the percentages of infestation incidence by pest showed have three peaks per year, were recorded in November, April, and July on all different mango varieties during both the two years. The obtained results indicated that the mango varieties varied significantly in their susceptibility to population density and the percentages of infestation incidence by P. oleae. Balady mango variety was the highest population density and was rated as highly susceptible (H.S.) to infestation by the total population density of P. oleae, followed by Ewaise and Goleck mango varieties were appeared as susceptible (S), then by Zebda variety was seemed asrelative resistant (RR). In contrast, Sediek variety had the lowest population density and was rated as moderate resistant (MR) of pest over the entire year. The results of this research here could be used as a tool for establishing IPM strategies against this pest.

Host preference of certain mango varieties to infestation with the mango shield scale, Milviscutulus mangiferae (Green) (Hemiptera: Coccidae) in Ismailia governorate, Egypt

A field study was carried out at a private mango orchard at Abu-Suwair district in Ismailia Governorate, Egypt during two successive years from (January 2018 to December 2019) to study the performance of some mango varieties to infestation with the mango shield scale, Milviscutulus mangiferae (Green) (Hemiptera: Coccidae). The obtained results showed that insect population of M. mangiferae occurred on all different mango varieties all the year round and has three peaks of seasonal activity per year, which was recorded in January, June/July and November over the year. The obtained results indicated that the mango varieties varied significantly in their susceptibility to population density of M. mangiferae. Ewaise mango variety was the highest population density and was rated as highly susceptible (H.S.) to infestation by the total population density of M. mangiferae, followed by Zebda and Fagri Kalan mango varieties were appeared as susceptible (S), while, Balady variety was observed to be relatively resistant (RR). But, Sakary variety had the lowest population density and was rated as relative resistant (RR) of pest over the entire year. These pieces of information can be useful for establishing IPM strategies against this pest.

Monitoring of the scale insect Icerya seychellarum (Westwood) infesting guava

The present study is on the spatial distribution and for estimating the optimum sample size for monitoring the populations of the scale insect Icerya seychellarum (Coccomorpha: Monophlebidae) on guava. The study was done in 2017–2018 and 2018–2019 in Luxor, Egypt. It was observed that the scale occurred year round and there were three to four peaks of seasonal activity: beginning of June, mid-September and mid-November in 2017 and the beginning of April, mid-June, mid-August and mid-October in 2018. Data on the indices of distribution and Taylor's and Iwao's regression analyses indicate significant aggregation behaviour. The regression models of Taylor's power law (b) and Iwao's patchiness (β) were both significantly >1, indicating that I. seychellarum had an aggregation distribution with a negative binomial distribution. The Iwao regression coefficients were used to determine the optimum sample size required to estimate populations at three fixed precision levels. The optimum size decreased with increased density in all levels of precision (5, 10 and 15%). These can be deployed to develop a sampling plan to estimate the population density accurately. Furthermore, the sampling protocol presented herein will be a tool for IPM decisions.

Environmental and individual effects on the behaviour and spawning movements of Lethrinus nebulosus on a coral reef

Spatial management of fish populations can potentially be optimised by incorporating responses to environmental variables, such as diel, tidal, lunar and seasonal factors, but individual variability in habitat use and behaviour may complicate such efforts. Acoustic tagging and tracking of 84 Lethrinus nebulosus in the Ningaloo Marine Park indicated that sizes of individual habitat utilisation kernels were similar across diel and tidal cycles, but varied greatly among individuals. Clearly differentiated diel and tidal habitat use patterns were evident in significant proportions of individuals, particularly in relation to tidal phase. For the majority of residents, home-range sizes were reasonably stable over periods of 2–4 years, but in some cases core areas did shift over time. At seasonal time scales, peaks of seasonal activity and home range area were recorded during spawning season (October–December). Long-distance return migrations to spawning locations were observed that were among the longest observed for any reef fish (over 130km). Suspected spawning-related movements were recorded almost exclusively in fish >500-mm fork length, and were semilunar, following quarter moons in October–December. Significant individual-level variability in movement and habitat use patterns, evident across multiple temporal scales, has important implications for the management of L. nebulosus populations.

A new Dendropsophus Fitzinger, 1843 (Anura: Hylidae) of the parviceps group from the lowlands of the Guiana Shield.

Many Amazonian frog species that are considered widely distributed may actually represent polyspecific complexes.. A minute tree frog from the Guiana Shield originally assigned to the allegedly widely distributed Dendropsophus brevifrons proved to be a yet undescribed species within the D. parviceps group. We herein describe this new species and present a phylogeny for the D. parviceps group. The new species is diagnosed from other Dendropsophus of the parviceps group by its small body size (19.6-21.7 mm in males, 22.1-24.5 mm in females), thighs dorsally dark grey with cream blotches without bright yellow patch, absence of dorsolateral and canthal stripe, and an advertisement call comprising trills (length 0.30-0.35 s) composed of notes emitted at a rate of 131-144 notes/s, generally followed by click series of 2-3 notes. Its tadpole is also singular by having fused lateral marginal papillae and absence of both labial teeth and submarginal papillae. Genetic distances (p-distance) are >5.3% on the 12S and >9.3% on the 16S from D. brevifrons, its closest relative. This species occurs from the Brazilian state of Amapá, across French Guiana and Suriname to central Guyana and is likely to also occur in adjacent Brazilian states and eastern Venezuela. This species is not rare but is difficult to collect because of its arboreal habits and seasonal activity peaks.

CLIMATE CHANGE IMPACT ON POPULATION DENSITY OF PARLATORIA DATE SCALE INSECT, PARLATORIA BLANCHARDII INFESTING DATE PALM TREES IN LUXOR GOVERNORATE, EGYPT

the present work was carried out to study the effect of climate change on the population density of the parlatoria date scale, P. blanchardii on date palm trees during the current (2009 to 2013) years and climate change conditions (2050 and 2100 years) at Esna district, Luxor Governorate. In order to compare the population density of pest under current data (average from 2009 to 2013 years) and future conditions, collected data was used to generate climate data under climatic changes conditions. The future climatic data values of (2050 and 2100 years) were used to predict the population density of P. blanchardii under climate change individually. Two climate change scenarios (A1 and B1) were used to assess the consequences of climate change on population density of pest on date palm trees under 2050 and 2100 years. The obtained results showed that monthly observations of total population of P. blanchardii had three to four peaks of seasonal activity per year. Also, the population density of insect increased in 2050s and 2100s as compared to base year data (average from 2009 to 2013 years). The percentages of explained variance (E.V.) indicate that the temperature was responsible for 70.7, 66.2 and 69.45% of the population changes of nymphs, adult numbers and total population of insect during the current year's data, respectively. The expected total population of insect will be higher at 2100s than expected through the 2050sunder the two scenarios (A1 and B1). Furthermore, scenario A1 (worst case) is higher in numbers of nymphs, adult females and a total population of P. blanchardii as compared with B1 scenario (best case). Also, scenario A1 at the 2100s will give the highest total population of insect and scenario B1 at 2050s gave the lowest one. The results showed that the increased temperatures during 2050s and 2100s will increase the seasonal activity of P. blanchardii in Luxor Governorate, Egypt. Generally, the population density of P. blanchardii increased depending on climate region and climate change Scenarios.

Seasonal occurrence of postharvest dried fruit insects and their parasitoids in a culled fig warehouse.

Parasitoids of dried-fruit insects were surveyed at a culled fig warehouse in Fresno, CA. Three parasitoids of pyralid larvae were found: Habrobracon hebetor (Say), Venturia canescens (Gravenhorst), and at least one species in the genus Goniozus Förster. Two parasitoids of pyralid pupae also were noted: Mesostenus gracilis (Cresson) and a new species of Psilochalcis Keifer. The latter is a new host association. Several beetle parasitoids were present, including Anisopteromalus calandrae (Howard), three species of Cephalonomia Westwood, Laelius centratus (Say), and Cerchysiella utilis Noyes. C. utilis, a parasitoid of driedfruit beetle, Carpophilus hemipterus (L.), is a new record for California. Most activity by parasitoids (detected by yellow flight traps) occurred directly above the fig mass. Pyralid parasitoids exhibited two peaks of seasonal activity; one in late summer through early fall, shortly after new figs were brought into the warehouse, and one in the spring. H. hebetor generally attacked older host larvae, whereas V. canescens equally attacked older and younger larvae, indicating that these two parasitoids may coexist by exploiting different portions of the host population. H. hebetor was active throughout the winter, suggesting that winter release of H. hebetor could be used to control diapausing pyralid populations in dried fruit and nut storage areas.

The ecology and behavior of the lone star tick (Acarina: Ixodidae). V. Abundance and seasonal distribution in different habitat types.

The abundance and seasonal activity of lone star ticks (Amblyomma americanum L.) were studied in different habitat types of a game refuge in Cherokee Co., Oklahoma during 1970 and 1971. Studies during 1970 were conducted in twenty-five 0.25-ha plots representing 16 habitat types; and 1971 studies were conducted in fifty-six 0.25-ha plots representing 17 habitat types. Drag-sweep samples were taken at biweekly intervals from early April to October 1970, and CO2-baited trap samples were taken at biweekly intervals from late March to early October 1971. Seasonal activity peaks of each stage of lone star ticks on CO2 traps and drag-sweep samples varied by as much as 2 months between the different habitats. The generalized adult activity peak occurred in late May and early June. Nymphs had 2 activity peaks in most habitats during 1971; one occurred during early June, and the 2nd occurred during August and September. Larval activity peaks occurred during July and early August in the meadow, prairie, glade, and opening-in-woods habitats, and during late August and early September in the wooded habitats, which included winged elm, persimmon, sassafras, American elm, hickory and black oak. High adult populations were found in winged elm, persimmon, sassafras, American elm, hickory, black oak, and southern red oak habitats. Low numbers of adults occurred in the hay meadow, native prairie, glades, maple, pine and white oak habitats. High nymphal populations were found in sassafras, winged elm, persimmon, opening-in-woods, hickory and American elm habitats. Low nymphal populations were found in glades, native prairies, hay meadows, pine and maple habitats. High larval populations occurred in the Johnsongrass, persimmon, sassafras, winged elm, opening-in-woods and post oak habitats. Low numbers were found in hay meadow, native prairie, maple, pine and white oak habitats.

On the occurrence of spread-F and the geomagnetic activity over Taipei, Taiwan

In this report, the authors have used the ionospheric data obtained at Taipei during the period of July 1957–June 1968 to investigate the solar cycle, seasonal and diurnal changes of the effects of the geomagnetic activity on the occurrence of spread-F activity. The cross correlation analysis is also used to determine the correlation coefficients with time shifts up to 10 days. The results show that the spread-F activity is negatively correlated with the geomagnetic activity throughout the years under investigations except for the year of 1961; there are two types of spread-F activity: one is the equinoctial type which is used to occur during the high solar activity and has its seasonal activity peaks in equinoctial months and diurnal peak in 2200 LST; the other is the summer type which is used to occur during the low solar activity and has its seasonal activity peak in summer, and diurnal peak in 0200 LST. It is suggested that the equinoctial type is closely associated with the appearance of the postsunset peak of ƒ 0F2 and is formed by the field aligned ionization irregularities caused by the fountain effect; and the summer type is formed by the ionization irregularities which are always existing in the topside ionosphere.

Activity Patterns of Bats over a Desert Spring

Bats were netted at a desert spring in southern Nevada for a total of 70 nights covering each month of the year. Two species, Pipistrellus hesperus and Myotis californicus, were active throughout the year with peaks of seasonal activity during the warmer months. Antrozous pallidus was netted in all seasons of the year. Air temperature was a major factor affecting seasonal and nightly activity with more bats being netted at higher temperatures. However, both M. californicus and P. hesperus were active at air temperatures between −8° and 31 °C. During the warmer months, when air temperatures remained above 15°C for the entire night, both species sustained activity throughout much of the night, but in winter months, they were active only shortly after dusk and activity ceased when air temperatures dropped. Evidence for foraging and insect activity during the winter is presented. The hypothesis of continued year-round activity of bats in warmer areas of the southwest is presented as an alternative to hibernation or migration.

Slugs in Gardens: Their Numbers, Activities and Distribution. Part 2

Section 8. Observations of slugs feeding in gardens indicate that very little of their food consists of plant material grown for human consumption or pleasure. In places where one crop only is grown, e.g. potato patches in the autumn, the damage would be higher owing to the absence of alternative food. Section 9. Mating of Agriolimax reticulatus and Arion subfuscus takes place out in the open on the surface of the ground after dark, the peaks being soon after the peaks of seasonal activity; the former species also mates to some extent throughout the year, whereas in the latter species mating is restricted to July-October. Arion hortensis and ater usually require some shelter, e.g. dead leaves, under which to mate, while it is presumed that the Milax species usually mate underground or under cover. Section 10. By weighing the slugs species by species en masse as collected and then calculating the weight per 100 individuals, regular changes in weight throughout the year have been found. This method has been found to be as satisfactory for assessing seasonal changes in weight as the half-hour method of collecting slugs is for measuring seasonal changes in activity numbers. The slugs are heaviest soon after the greatest numbers are found active and at the time when the peak of mating occurs. Section 11. The distribution of the species varies from garden to garden. Arion hortensis and Milax gracilis are most abundant in the gardens at the bottom of an old river bed slope and decrease steadily until their lowest numbers occur half-way up it. Milax sowerbyi has a ridge of abundance across the slope. Arion subfuscus is almost completely absent on the east side of the valley. Two particular gardens form the focal point of abundance of Limax maximus, and Arion ater is more abundant in gardens of recent origin in close proximity to coarse grass areas than in old well-established gardens. These distributions have persisted month by month throughout 2 years. Section 12. There is some evidence that each species has its own regular curve of nightly activity, providing of course weather conditions are suitable. In the summer activity appears to be more closely adjusted to the time of sunset than in the winter. Immature specimens of Arion hortensis preponderated in steadily decreasing numbers in twilight collections made from May to December. Section 13. All species are fully active at about 40 degrees F., but some activity continues until almost freezing point; below this there is no activity. Some species, e.g. Milax gracilis, resume activity after cold spells later than others, e.g. Agriolimax reticulatus, perhaps owing to their deeper penetration of the soil. Lack of surface moisture seems to be one of the factors limiting activity. Slug activity in rainless periods is reduced more at some periods of the year than at others. Rainless periods in the spring have less effect on limiting activity than summer droughts. This is probably due to the different water contents of the soil at these seasons. Activity is reduced while heavy rain is actually falling and also in heavy wind. The optimum conditions for slug activity may be summarized thus: a warm still night with plenty of surface moisture either in the shape of recent rain or dew.