J. Eco. Heal. Env. 6, No. 1, 47-55 (2018) 47 Journal of Ecology of Health & Environment An International Journal http://dx.doi.org/10.18576/jehe/060106 Population Dynamics of Terrestrial Spiders (Arachnida) at Qena Governorate, Upper Egypt Ahmad. H. Obuid-Allah1, Amal. A. Mahmoud2 and Elamier. H. M. Hussien2* 1 Department of Zoology, Faculty of Science, Asyut University, 71515 Asyut, Egypt. 2 Department of Zoology, Faculty of Science, South Valley University, 83523 Qena, Egypt. Received: 1 Oct. 2017, Revised: 10 Dec. 2017, Accepted: 21 Dec. 2017. Published online: 1 Jan. 2018. Abstract: In the present study, monthly and seasonal fluctuations of densities of terrestrial spiders were recorded in six different sites at Qena Governorate during the period of one year (February, 2012 - January, 2013). The study revealed the occurrence of 1247 specimens belonging to 14 families and including 23 species of order Araneae. Family Salticidae recorded the highest number during the whole period of study (278 specimens) while family Agelenidae recorded the lowest number in the same period of study (4 specimens). It was observed that the maximal number was collected from Thanatus albini (199 specimens), while Halodromus barbarae was the least species in number since only 2 specimens were collected. The densities of the recorded spiders varied seasonally and the general seasonal peak was recorded during autumn (363 specimens), while the lowest density was observed during winter (215 specimens). Regarding the sex ratio of the collected spiders from all sites, it was clear that there were 213 adult male specimens, whereas the adult females were represented by 440 specimens. Ecological factors which may influence the distribution of the recorded spiders were also recorded; Air temperature (oC), relative humidity (%), evaporation (mm) and wind velocity (Knots). Keywords: Spiders, Population dynamics, Qena governorate, Upper Egypt. 1 Introduction spiders [7,8]. The importance of spider predation in regulating specific Spiders are members of the phylum Arthropoda, the large prey populations is controversial [9, 2]. However, there are group of animals with jointed legs and a hard outer some studies that suggest a significant control of specific skeleton. They belong, more specifically to class prey populations by an assemblage of spiders [10, 11]. In Arachnida, which includes animals with four pairs of legs, the form of a multi-specific assemblage, spiders live in no antennae or wings, and only two body regions; a different habitats and present different body dimensions cephalothorax which contains (the brain, poison glands and and predatory behaviors, all of which increase the stomach) carapace, sternum, eyes, chelicerae, mouthparts, probability of encountering potential prey. Many legs and palps) and the abdomen (spinnerets, genitalia, researchers have provided descriptions of spider species lungs and respiratory tracheae) [1]. abundance or composition in a variety of agro ecosystems Spiders are the most abundant insectivorous predators of [12]. Other researchers provided quantitative observations terrestrial ecosystems [2,3,4]. Spiders are among the on the abundance of spiders [13] or recorded spider highest ranked predators in food chains, and their predation events [11]. phenology and community structures are closely affected Concerning diversity; spiders have been reported to occur by disturbance and vegetation structures compared with in peak numbers of more than 1,000 individuals per m2 species inhabiting undisturbed temperate areas. Species in [14]. At the same time, they are one of the most diverse habitats subjected to a high level of disturbance tend to arthropod orders and exhibit a great variety of foraging have more than one generation per year [5,6]. Habitats strategies [15,16]. The spiders’ diet is made up primarily of exhibiting a higher level of spatial heterogeneity are insects from various taxa, and also of other spiders [17]. associated with high abundance and species richness of Eggs, larvae, and adults of many different insect pests are *Corresponding author e-mail: [email protected] © 2018 NSP Natural Sciences Publishing Cor. 48 A. Obuid-Allah et al.: Population Dynamics of Terrestrial Spiders … eaten by spiders [18,19,20]. Because of their high sweep net and pitfall trap. Specimens of collected spiders abundance and insectivorous feeding habits, spiders are were put in a 10 centimeters diameter Petri-dish filled with suspected of playing an important role in the balance of 70% ethyl alcohol. Examination was carried out with the nature [18,21,22,20,3,23,24]. aid of binocular stereomicroscope. Specimens were labeled for: date, habitat, locality, trapping method by a pencil on a On reviewing literature that focused on the Egyptian spider slip of paper attached to specimen inside the preserved fauna, it could be concluded that it stills incompletely tube. The collected specimens were identified to the species known due to scarcity of studies on this group especially in level whenever possible and others on genus or family Upper Egypt. So, the present work was focused on Qena level. Identification of the specimens was done by the help Governorate (26.170 N, 32.70 E) to study population of the following keys, description, catalogues and literature; dynamics of spiders in different habitats of this region as [25,26,27,28,15, 29,30,31,32,33,34,35,36,37] and finally, well as effects of some physical factors on the abundance of species identification was confirmed by Mr. H. K. El- the collected taxa. Hennawy the expert in spider’s identification in Egypt. The recorded data of the weather parameters included 2 Material and Methods temperature (oC), relative humidity (%), evaporation (mm) and wind velocity (Knots), which labeled as (Tmin, Tmax, In the present study, samples were collected every 2 R.H.min, R.H.max, Evab. And W.V.), were obtained from weeks during a period of one year (from February, 2012 South Valley University-meteorological research station till January, 2013) from different six sites. These sites (SVU-meteorological research station). Analysis of were chosen to cover all parts of Qena governorate and Variance on SPSS software package (SYSTAT statistical illustrated in the map (Fig.1). Three sampling methods program, version 17) was used to test the present data. were used in the present study as follows; hand pick-up, Table 1. The monthly mean of weather factors for the study area during the period of investigation. Mean Mean Months T.(Min) T.(Max) R.H.(Min) R.H.(Max) Evap. W.V. Temp. R.H. February- 2012 10.1 24.8 13.9 19.4 55.7 43.0 7.6 65.6 March-2012 11.8 27.1 19.6 15.8 51.4 30.8 9.5 53.3 April-2012 18.8 35.3 27.0 6.7 31.2 19.0 15.0 45.4 May-2012 23.4 38.8 31.1 7.6 29.2 18.4 17.8 56.1 June-2012 26.0 41.3 33.7 7.1 30.6 18.8 18.9 66.8 July-2012 27.0 41.0 34.0 11.5 35.4 23.5 19.6 93.0 August-2012 25.7 40.0 32.9 10.7 37.4 24.1 20.4 88.7 September-2012 23.2 37.6 30.4 15.5 47.2 31.4 17.1 102.3 October-2012 21.4 35.8 28.6 14.5 42.8 28.7 14.3 81.2 November-2012 16.3 29.6 22.9 23.5 57.4 40.5 10.4 86.3 December-2012 9.8 23.4 16.6 28.5 74.0 51.2 6.7 72.1 January - 2013 5.8 20.7 13.2 28.3 69.7 49.0 5.7 57.2 Mean – 2012 / 2013 18.28 32.95 25.32 15.76 46.83 31.52 13.6 72.33 T (Min) = Minimum of temperature °C, T (Max) = Maximum of temperature °C, R.H (Min) = Minimum of relative humidity (%), R.H (Max) = Maximum of relative humidity (%), Evap. = Evaporation (mm), W.V. = Wind Velocity (Knots). © 2018 NSP Natural Sciences Publishing Cor. J. Eco. Heal. Env. 6, No. 1, 47-55 (2018) / http://www.naturalspublishing.com/Journals.asp 49 Table 2. The identified families and species from all sites during the period of investigation. No. Family Species No. Family Species Agelenidae Benoitia lepida 1 [38] [39] Oxyopidae 13 Peucetia sp. Argiope trifasciata [52] 2 [41] Cyrtophora citricola Halodromus barbarae 3 Araneidae 14 [40] [41] [53] Philodromidae [52] Thanatus albini 4 Larinia sp. 15 [45] Eutichuridae Cheiracanthium siwi Pholcidae Artema atlanta 5 16 [42] [43] [54] [55] Trachyzelotes lyonneti 6 17 Heliophanillus sp. Gnaphosidae [45] [44] Zimiris doriai Plexippus paykulli 7 18 Salticidae [46] [56] [45] Linyphiidae Erigone dentipalpis Thyene imperialis 8 19 [47] [48] [57] Sparassidae Eusparassus walckenaeri 9 Pardosa sp. 20 Lycosidae [58] [45] [49] Wadicosa fidelis Paidiscura dromedaria 10 [50] 21 Theridiidae [59] Oecobiidae Oecobius putus [49] 11 22 Theridion sp. [51] [39] Oxyopidae Thomisidae Thomisus spinifer 12 Oxyopes sp. 23 [52] [49] [60] Table 3. Total number (N) and percentage (%) of sex ratio for all species collected from all sites during the period of investigation. Sex ratio Male Female Total Sites N. % N. % N. % Site I 33 34.0 64 66.0 97 14.9 20 24.4 62 75.6 82 12.6 Site II Site III 23 27.1 62 72.9 85 13.0 Site IV 43 36.4 75 63.6 118 18.1 Site V 49 40.2 73 59.8 122 18.7 Site VI 45 30.2 104 69.8 149 22.8 Total 213 32.6 440 67.4 653 100.0 Table 4. Total number (N) and percentage (%) of sex ratio for all species collected from all seasons during the period of investigation.