Behavioural Studies of Enallagma vansomereni (Odonata: Zygoptera, Coenagrionidae) in Qena Governorate (

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INTRODUCTION
Several studies have explored the behavior, movement, and dispersal patterns of Odonata (zygopteran dragonflies).Obtaining a comprehensive understanding of individual behavior and movements often requires extensive tracking over multiple days.Adult Odonata, in particular, are well-suited for ecological and dispersal studies due to their relatively large size, abundance, diurnal activity, ease of capture, and habitat preference for open areas where they are easily observable (Moore, 1957).Mark-recapture techniques have proven invaluable in these studies, allowing for the identification and subsequent observation or recapture of individuals.Corbet, Longfield, and Moore (1960) reviewed various mark-recapture methods, highlighting cellulose paint as a commonly used and effective tool.Odonata, including damselflies (Zygoptera), have been identified as excellent model organisms for mark-recapture studies (Mollet et al., 2015).In many damselfly species, mobility is limited (Ueda, 1976;Garrison, 1978;Parr & Parr, 1979;Utzeri et al., 1984;Banks & Thompson, 1985;Eberhard, 1986).By marking wild individuals, researchers can estimate population densities and key demographic parameters such as survival rates, longevity, and emigration rates.
Odonates have served as valuable model organisms for developing mark-recapture methods due to the ease of obtaining large datasets.One such method for analyzing markrecapture data was tailored to assess survival rates among age classes in Enallagma vansomereni.Furthermore, Van Noordwijk (1978) conducted an extensive study on an odonate community, devising a regression-based approach for analyzing mark-recapture data.More recently, Rassim Khelifa et al. (2021) explored the integration of high-speed videos in mark-recapture studies of insects.
Den Boer (1990) defined dispersal as the undirected movement away from the original habitat, contrasting it with migration, and emphasized its significant impact on population dynamics (Dieckmann et al., 1999).Corbet (1980) underscored dispersal as a crucial demographic process in population ecology.Among odonates, temporary emigration for maturation is common in females and teneral individuals (Templeton & Rothman, 1981).McPeek (1989) investigated the varying dispersal tendencies among Enallagma damselflies (Odonata) across different habitats in southwestern Michigan, USA, focusing on the mechanisms involved.Despite its importance, the study of damselfly dispersal has been limited by its infrequent documentation, which has hindered investigations into whether certain individuals are more predisposed to dispersal than others (Anholt, 1990).
Most empirical studies on behavior and dispersal of odonate have primarily examined movements within patches (Garrison & Hafernik, 1981;Conrad & Herman, 1990;Jenkins, 2001) or movements between adjacent water bodies (Van Noordwijk, 1978;Koenig & Albano, 1987;Thompson, 1991;Stettmer, 1996).Schutte et al. (1997) conducted observations and captures of Calopteryx splendens over 64 days between May 16th and August 30th, 1993.Individuals were captured upon initial observation and marked with points on their wings using fast-drying lacquer.However, expansions in distribution due to factors such as deforestation, agricultural and mining development, and global warming have been observed in odonates (Sternberg et al., 1999).This suggests that certain species are capable of moving across unsuitable habitats.
Odonata, particularly damselflies, are ideal candidates for detailed dispersal studies due to several factors.Firstly, they are large, conspicuous, and easily handled and observed.Secondly, most dispersal events are relatively straightforward to monitor, as the majority of movements occur between populations inhabiting water bodies less than 1 km apart (Moore, 1953;Stettmer, 1996;Conrad et al., 1999). Kelvin Conard et al. (2002) investigated the characteristics of distraction Ischnura elegans and Coenagrion puella (Odonata), including age, sex, size, morphological traits, and ectoparasitism.Male mobility, particularly for those observed infrequently, proved challenging to estimate.Some males exhibited strong site fidelity, while others were sighted at different locations during each observation.Males and several females were gently captured using nets and marked with unique combinations of white and/or red paint spots on the outer edges of their wings.Marked individuals were released back into their capture site after approximately one minute.Mohamed (2024) studied the survival, behavior and mark-recapture of Ischnura elegans in Dakahliya Governorate (Egypt).

Study Sites:
The study directly investigates both within-patch and between-patch dispersal of Enallagma vansomereni, utilizing data obtained from mark-release-recapture techniques across six populations located in Nag'e Hamady city, Taramsa village, and Mazlaan in Qena Governorate, Egypt.Understanding movements between these stations is particularly relevant for this rare species, as it inhabits six fragmented habitats in Egypt.The research aims to assess the variability in dispersal tendencies within the damselfly Enallagma vansomereni (Odonata: Zygoptera) populations and explore potential reasons for this variability.
To achieve such research, six stations were chosen in Nag'e Hamady city (4 stations), Taramsa village and Mazlaan in Qena Governorate (Egypt).To survey these above-mentioned insects we used the sweeping net.The field study was conducted from March to the end of August 2022.
Enallagma vansomereni individuals were collected at six stations in Qena Governorate, each station (200 meters) being divided into 20 sections of 10 meters, to determine.The author next examined if significant dispersal occurred between stations by following the Enallagma vansomereni composition through the flight season.Dispersal between stations with Enallagma vansomereni would be expressed as a change in adult species compositions at one or all of the stations through time.
Although fieldwork was carried out between 21 st March and 29 th August, covering most of the flight season of Enallagma vansomereni.The individuals of each station are distinguished by a different color from the individuals of other stations.Unmarked individuals were each given a number of points on the wings, this means that on the first visit, we made one point on the wing with an indelible pen and on the second time we made two points and so on, and the individual was released at the place of capture.After marking, the damselflies resumed their normal behaviour rapidly.When individuals were recaptured, their sex, the date of marking, the section in which they were recaptured and the number of points were noted.
To employ capture-recapture methods with a mobile animal population, it's essential to mark captured animals individually upon their initial capture, without marking them again subsequently.These individual marks must enable the identification of capture and recapture times for all individuals observed during the sampling period.Capture-recapture data were collected to investigate population structure changes throughout the flying season and to compare the survival rates of newly marked animals with those that had been marked previously but were still alive (Robinson et al., 1983).

Daily Movement:
Enallagma vansomereni was observed and captured on one day at six stations: They were captured with a net and marked with consecutive numbers of points on the wings by many colors and then immediately released in the same sector in which they had been captured.During each recapture, the recording involved counting the number of points and noting the wing color.

Size of Population:
The mark-recapture technique is employed to estimate the size of a population when it's not feasible to count every individual.The fundamental concept involves capturing a small sample of individuals, marking them harmlessly, and releasing them back into the population.Later on, another sample is captured, and the number of marked individuals in this second sample is recorded.In smaller populations, the likelihood of recapturing marked individuals is higher compared to larger populations.This relationship can be mathematically expressed using the following equation.The formula used for estimating the number of individuals in a population using markrecapture techniques is: N = (M.C) / R N is the estimated number of individuals in the population.M is the number of individuals initially captured and marked.C is the total number of individuals captured during the second sampling session (both marked and unmarked).R is the number of individuals recaptured during the second sampling session, specifically those that were marked during the first capture.

Size of Population:
Table 4 displays the count of Enallagma vansomereni captured, marked, and subsequently recaptured a week later after they had dispersed into the population.The size of the population in the six stations was 97, 128, 120, 75, 62 and 52.

DISCUSSION
Most of the marked individuals migrated distances of less than one hundred meters, aligning with findings by Schutte et al. (1997), Zohreh et al. (2023), and Mohamed, I. (2024). However, St. Quentin (1964) reported much smaller distances, suggesting that these distances may reflect individual home ranges rather than dispersal activities.McPeek (1989) observed minimal movement between lakes in four Enallagma species.Michiels et al. (1991) noted that only about 20% of adults were likely to have emerged locally, indicating that the majority had immigrated over distances exceeding 1.75 km.Rainfall can impact survival, although substantial downpours are typically necessary (Cordoba-Aguilar, 1993).
Mark-recapture experiments are often conducted over months or years, resulting in relatively few encounter occasions.In contrast, daily monitoring in adult insect markrecapture studies yields numerous encounter occasions.Insect studies involve larger numbers of individuals with lower recapture rates due to their small size and high mobility, resulting in sparse data.Consequently, large insect populations may not be suitable for combined analyses of recoveries and resightings, which are effective for unbiased estimations of survival and emigration in vertebrates (Frederiksen & Bregnballe, 2000).
The mobility of Enallagma vansomereni observed in this study surpassed previous findings in several aspects.Hunger & Röske (2001) reported that 96% of individuals in a population in southwestern Germany remained within 25 meters of their marking site.In contrast, in this study, a lower proportion (20-47%) of individuals remained within such close proximity, with the majority (46-80%) moving within their natal station.Maximum movements within stations and between stations were notably greater, reaching distances of 610 meters and 1060 meters, respectively, compared to 170 meters and 300 meters observed by Hunger & Röske (2001).Enallagma vansomereni exhibited movements of up to 360 meters between stations in the present study, consistent with findings by Hold (1997), Hopkins & Day (1997), Jenkins (1998), and Mohamed (2024).Jenkins ( 2001) noted a low rate of movements (1/1223 individuals) between adjacent streams (75-150 meters apart) in the New Forest.In southwestern Germany, the maximum distance between sampled patches was approximately 600 meters (Hunger & Röske, 2001), whereas in Dakahliya, Egypt, it was approximately 230 meters (Mohamed, I. 2024).Conrad et al. (1999) noted that 15% of recaptured individuals had dispersed to another pond.Den Boer (1990) suggested that weaker fliers might actually be better dispersers than stronger fliers, hypothesizing that they are less able to resist wind-driven movements if dispersal occurs passively.
It is noteworthy that adult Enallagma vansomereni were capable of moving significant distances within a single day, with observations of movements up to 360 meters.In contrast, larger zygopterans such as Calopteryx splendens and C. Virgo can cover distances of around 1 km within one or two days (Stettmer, 1996).
According to Zohreh et al. (2023), the survival rate of female I. elegans was notably lower than that of males.Mohamed (2024) reported a survival rate of 85.0% per day for I. elegans, with differences observed between males (81.0%) and females (50.4%).In our study, the daily probability of survival in Enallagma vansomereni was estimated at 83%, with variations noted between males (79%) and females (49%).

Declarations:
Ethical Approval: Ethical Approval is not applicable.Authors Contributions: I hereby verify that the author mentioned on the title page have made substantial contributions to the conception and design of the study, have thoroughly reviewed the manuscript, confirm the accuracy and authenticity of the data and its interpretation, and consent to its submission.Competing Interests: The authors declare that they have no competing interests.