Ecology of Desert Rodents of the U.S.S.R. (Jerboas and Gerbils)

Abstract

The rodents are an integral component of the desert biogeocenose. Soviet zoologists have been conducting considerable research work on the rodent fauna of the USSR for the last several decades. In this communication, we have made an attempt to collate the available informatio non the ecology of two groups of rodents of the Russian deserts, viz. the Jerboas and the Gerbils. Under every rodent species, as far as possible, we have included its distributional range, habitat preference ,activity pattern, association and interaction with other rodent species, food, various aspects of reproduction, hibernation and predators. The species which are included in this Chapter are: Cardiocranius paradoxus, Salpingotus crassicauda, Allactaga euphratica, elater, sibirica, major, severtzovi, bobrinskii, Alactagulus pygmaeus, Pygeretmus platyurus, Dipus sagitta, Scirtapoda telum, Jaculus turcmenicus, Eremodipus lichtensteini, Paradipus ctenodactylus, Meriones persicus, vinogradovi, tamariscinus, blackleri, unguiculatus, meridianus, libycus, crassus zarudnyi, Rhombomys opimus. The arid zone of the USSR In the Soviet Union, desert and semidesert regions make up almost 12 per cent of the country's total area. The proportion rises to between 50 and 60 percen in the Central Asian REpublics of Uzbekistan, Kazakhstan and Turkmenistan. The territory includes: 1. the dry steppes, semi deserts and deserts of the Armenian and Azerbaidjanian uplands; 2. the semi-deserts of Azerbaidjan and the North-Caspian plains; 3. the Volga-Ural sands; 4. the semi-deserts of the North-West Caspian region; 5. the hplateaus of usturt, Mangishlack and desert of Betpackdala; 6. the deserts of Kazakhstan and Middle asia; 7. the upland steppes and semi-deserts of Tian-shan and Pamir; and 8. the upland steppes and semi-deserts of South TransBaikal. The arid territory of the USSR belongs to the category of Moderate Zone deserts. The gregion has a strong continental climate with very low temperature regime: 25-30C (up to 50) in tsummer, and from -37 to -45 C in winter. Annual precipitations are limited to 70-250mm per year. Summers are very hot and the rate of evaporation is very high. Annual and even daily fluctuations of the atmospheric humidity and of air and soil temperatures are very high. The deserts of the USSR differ from those of Central Asia and the Mediterranian region in respect of the seasons of precipitation. Rain and snow fall in the deserts of the USSR during the cold period of the year, chiefly in spring and autumn. The seasonal distribution of precipitation is more even in the northern deserts. Usually the evaporation of moisture exceeds precipitation by 7 to 8 times. The intensity of solar radiation on the slopes of the Middle Asian deserts is of the order of 140 Kcal/cm2/year and it is quite sufficient for the growth and development of desert plants.