English Abstract
University: king Saud University College: College of Science Department : Zoology Department
Branch/ Track: Ecology of animal and pollution
Title: Amphibian Diversity in the Wetlands of Southwestern Saudi Arabia Name of Researcher: Abdulaziz R. M. Al-Qahtani
Degree: Doctor philosophy
Date of Discussion: 1-2- 1432 H (5-1-2011 G) Abstract:
Amphibian diversity has been studied in wetlands of Southwestern Saudi Arabia, yet no enough studies had been performed to provide basic information about the species life, especially the geographical distribution and dispersions. For the implementation of this study, a field study has been performed which considered as the main part of the work procedures used in this research. Additionally some other laboratory work has been conducted as a complementary portion of the work plan during the period from 2008 G to 2009 G. The main result of the study was recording of seven species of tailless amphibians (Anura), which belong to three families, firstly, Bufonidae family which include four species, Bufo tihamicus, Bufo dhufarensis, Bufo arabicus and Bufo viridis, secondly Hylidae family represented by only one species, a tree frog Hyla savignyi, and finally Ranidae family represented by two species, Rana ridibunda and Euphlyctis ehrenbergii.
During this study larval stages (tadpoles) of each amphibian species, were described where tadpoles of six species were collected and the tadpole of Bufo viridis, was hardly to be obtained. In this study tadpoles of two species have been described for the first time in the Arabian Peninsula,
these species include the tadpoles of Hyla savignyi and the tadpoles of Rana ridibunda. General description and diagrammatic representation were carried out to illustrate the general shape of the body and the mouth parts which can be used as tools in classification of species.
The seven species of amphibians are geographically distributed in the majority of the study area in Southwestern Saudi Arabia, where Bufo tihamicus was commonly existed along the coastline of the Red Sea from the southern region of Jazan until near Al-eeth at latitude 21° north, and the species was not extending to interior areas often since it has not been recorded to be present away from the coastal areas. The distribution of Bufo dhufarensis reaches to the most of Tehama areas, from the far south of Tehama to the north of Mecca. The current study recorded the distribution of the Bufo arabicus widely in most of the study area, which included the Tehama region, the southwest highlands and the inland areas.
The current study confirmed the spread of the Bufo viridis in the Saudia, even though the previous studies have shown the non-possibility of its existence in southwestern area of Saudia, Bufo viridis was recorded at three sites in Asir Heights, stationed in Soda area.
Hyla savignyi distributed along the Sarawat mountain chain from the south of Taif, to the south of Abha, Hyla savignyi has been recorded in several new locations in the southwest highlands. Rana ridibunda was recorded in eight sites of Asir region and at one site in the Baha area, the finding in Baha was considered as a new record, where it was not recorded before in north of Tanumah in all previous studies.
Euphlyctis ehrenbergii spread widely in the areas of Tehama from the far south of the study area to the north of the Al-leeth also, have been recorded in a few locations in the eastern study area in
inland districts. In addition to recording this species at a single site in the southwest highlands in Ayyash dam, on a height of 2050 meters above sea level.
The population size and abundance vary among amphibian species in southwest region of Saudi Arabia. The Bufo arabicus showed high availability in many locations, as well as distributed in different aquatic environments in all points of the study area. The Euphlyctis ehrenbergii was found to be in great abundance in the valleys flowing environment Tehama coastal areas, in addition to its record in a number of aquatic environments. Whereas Bufo tihamicus, Bufo dhufarensis and the Hyla savignyi were found to be in medium abundance in their natural habitats in terms of size of the population and the number of sites occupied by species. Rana ridibunda showed low abundance and limited distribution sites of Sarawat heights. While Bufo viridis was rarely found in environments, it was recorded only in three locations in the area of Soda.
The size of the population of Bufo arabicus and Euphlyctis ehrenbergii was found in high-density, when estimating density by Hanson estimator (Hanson, 1968). The estimation in the present study showed that there was about 172 Bufo arabicus per 1000 m², and about 188 Euphlyctis ehrenbergii per 1000 m².
Amphibians of southwest of the kingdom are exposed to many threats of natural and industrial types, which contributed to the loss of the environment of these species and many of its members, it was noted that the drought is the most dangerous natural threat affecting the survival of these species, due to their close association with aquatic environments, are declining in number and size, many of the aspects of the study areas were characterized by severe drought and the scarcity of rainfall, the water
dried up in several sites in northern Tehama such as Sitarah valley, Al- Kharrar , Al-leeth valley and Dugah valley, some mountain streams in the Sarawat highlands such as the valleys of Brahrah, Aziza and Tahlal, in addition to some dry valleys in the Interior areas. Among the most threatening factors on amphibians are industrial threats resulting from different human activities, perhaps the most important located pollution was pesticides which were sprayed in water sites from streams, springs, ponds and dams, to kill mosquitoes carrying diseases such as malaria fever, dengue fever, and Rift valley fever.
Some government agencies work on drying of wetlands, ponds, basins and aquifers in the areas of Tehama to prevent mosquito breeding and thus lead to the loss of humid environments for frogs and toads, are also subjected to threats to amphibians such as the withdrawal of natural water formed in the valleys and streams by the local population, for sale as drinking water, which contributed in reducing the level of the water reserve significantly, as it is to get rid of excess sewage from cities in the valleys, in addition to exposure to the risk of some species of vehicles on the roads ran when wells and mobilize water and near the farms. Also reached the hands of man to waste disposal and solid waste into the water areas such as streams, springs and dams, spread harm to engage in human activities near these aquatic environments, and water use for different purposes or the entry of vehicles into natural aquatic environments.
