Search published articles


Showing 4 results for Population

Ashraf Jazayeri, Fahimeh Saberi, Tayebeh Mohammadi,
Volume 3, Issue 1 (3-2021)
Abstract

The Marsh frog, Pelophylax ridibundus (Pallas) is distributed in Central Europe from northeastern France, north to the southern shorelines of the Baltic Sea (and extreme southern Finland), south to northeastern Spain, northern Italy and the Balkans including eastern Greece, east to approximately 81° E in Asiatic Russia, and south to western Iran and Afghanistan. The present study has been conducted on populations of P. ridibundus in the northern, eastern and southern regions of the Shadegan Wetland of Khuzestan Province, Iran with the aim of examining some aspects of its morphology and karyotype. Frog specimens were collected from different portions of the Shadegan Wetland during spring and autumn 2016 and transferred to the laboratory. According to the morphological results, three color patterns are identified among the samples in terms of the morphology, morphometry and sex - according to the sex independency test. T-test results between males and females indicate a significant difference in all traits and the results of a T2 Hotelling test show that there is sexual dimorphism between males and females. However, the results of multivariate analysis of variance (MANOVA) illustrate a separation between males of the northern region and the two other regions, and no differentiation between females in the eastern and southern regions of the wetland. The karyotype of the species in the wetland included 2n = 26, one pair of which had a sex chromosome.
 

Yatin Kalki, Chayant Gonsalves, Daniel B. Wylie, Karthik A. K. Sundaram, Tristan D. Schramer,
Volume 3, Issue 2 (6-2021)
Abstract

Systematic and thorough studies of snake populations across large areas are rare in the tropics. Bengaluru city in southern India has not had a thorough checklist of snakes in over a century, during which time land-use changes, taxonomic revisions, and fluctuating reptile populations have left the current status of snakes of this region unclear. We combine data from snake rescues, visual encounter surveys, and other reliable records to generate a contemporary checklist of 33 snake species (15 of which are novel) present within the Bengaluru Urban District with comments on their apparent habitat preferences. We also provide evidence and insight on six additional species that have not been recorded but potentially occur within the limits of the district. Compared with the earlier checklist, all but 4 species (Naja naja, Ptyas mucosa, Daboia russelii, and Fowlea piscator) have shown considerable decline within city limits. Additionally, all of India’s “Big Four” medically significant venomous snake species (Naja naja, Bungarus caeruleus, Daboia russelii, and Echis carinatus) are found within the district. Naja naja and Daboia russelii appear to be well-adjusted to urbanization with serious ramifications for human-wildlife conflict and healthcare in the future as the majority of Indian snakebite deaths can be attributed to these two species. The population trajectory of Daboia russelii is of particular interest as it was classified as “not common” in the previous checklist, but it is presently one of the most abundant snake species in the area. Our study provides a new baseline that can be used to monitor ophidian population trends going forward.

Naresh Subedi, Babu Ram Lamichhane, Yajna Nath Dahal, Ram Chandra Kandel, Madhuri Karki Thapa, Rajan Regmi, Binod Shrestha,
Volume 3, Issue 2 (6-2021)
Abstract

Conserving tigers (Panthera tigris) in highly fragmented landscapes is a daunting task. Terai Arc Landscape (TAL) at the base of the Himalayas aims to connect the remaining Tiger habitats in southern Nepal and northwestern India. Tiger population clusters in central (Chitwan-Parsa) and western (Bardia-Banke) Nepal are distinct with limited connectivity in recent past. We present the photographic evidence of Bengal tiger (P. tigris tigris) from forest patch between these population clusters for the first time. The photographs were obtained during camera trap survey across Chure region of Nepal in 2018. Two adult tigers–a female and a male—were photographed ~40 km apart. This record indicates the possibility that tiger habitat extends outside the protected areas in Nepal and natural linkages between Chitwan-Parsa and Bardia-Banke tiger population clusters through forest corridors along the Chure region. Conservation efforts should also focus on the forests outside protected areas especially the critical biological corridors to conserve tigers in TAL via a meta-population approach.

Maryam Rezaie, Fariba Ardeshir,
Volume 5, Issue 2 (6-2023)
Abstract

The two-spotted spider mite Tetranychus urticae Koch is one of the most important pests of agricultural crops worldwide, infesting a wide range of plants including some economically important crops. An investigation was carried out to study the life table parameters of five Iranian populations of T. urticae from Urima, Dashtnase, Faryman, Razkan and Tehran under laboratory conditions of 27 °C, 60% RH and 16 L: 8 D hours on Malus domestica Borkh leaves. There was a significant difference in the developmental time of T. urticae among tested populations. The total survival rate of T. urticae ranged from 76% to 81%. The adult longevities were significantly different. The adult longevities of the Faryman and Dashtnase populations were different from the Razkan population. Total fecundity of the Urima, Razkan and Tehran populations were higher than that observed for the other tested populations. The highest value of R0 was for the Urima and Dashtnase populations and the lowest was for the Faryman population. The r values of the Dashtnase (0.248 day-1) and Urima populations (0.200 day-1) were significantly higher in comparison to the Faryman population (0.124 day-1). The observed variation of the two-spotted spider mite collected from different localities showed that ecological factors such as geographical separation can influence the life table parameters of a phytophagous organism.


Page 1 from 1     

  | Journal of Animal Diversity

Designed & Developed by : Yektaweb