Analysis of the activity rhythms of the great gerbil (Rhombomys opimus) and its predators and their correlations based on infrared camera technology

Abstract

Rodents have long plagued forestry production in China, particularly in desert areas in northwestern China, where prevention and monitoring techniques are lacking. Predators are important in regulating rodent populations, and determining how to maximise the role of predators in the comprehensive management of rodent pests is one of the most important issues in rodent control. To accurately understand the activities and vegetation damage patterns of the great gerbil (Rhombomys opimus) in a desert forest area, as well as the activities of its predators, we set up infrared cameras in the Sal Hu Song desert forest region of Altay city, Xinjiang Uygur Autonomous Region, China, in December 2016 and conducted one year of field monitoring of R. opimus and its predators. A total of 2407 independent and valid photographs of R. opimus and its predators were collected. By calculating the relative abundance index, we analysed the activity rhythms of R. opimus and its predators and calculated the correlations of their activity rhythms. The relative abundance of R. opimus was 237.75 in Sal Hu Song, and the predators were mainly the long-legged buzzard (Buteo rufinus) at 94.50, marbled polecat (Vormela peregusna) at 45.74, and red fox (Vulpes vulpes) at 44.26. R. opimus is a typical diurnal animal, with activity peaks occurring between 10:00 and 12:00 and between 17:00 and 19:00, and its activities were mainly movement and foraging. Over the year, R. opimus had two peak activity periods, March and September–October. The peak activity periods of V. peregusna were March and September, while the peak activity period of V. vulpes was February–March. The peak activity period of B. rufinus was June. Among these three predators, the activity rhythms of V. peregusna had the highest correlation with those of R. opimus. This study will contribute to monitoring and managing pest animals in these desert areas.