The fate of Scincus mitranus in the face of climate change: A Qatar case study

Abstract

Over the past 22 years, annual mean temperatures have increased by 1°C in Qatar and even greater increases are projected in the future. Since lizards depend on thermoregulation to survive, how do such rises in air temperature affect the Eastern sandfish Scincus mitranus in Qatar? S. mitranus exclusively inhabit Barchan dunes, which are restricted to the South-Eastern region of the country and are currently disappearing due to the North-Westerly Al Shamal winds driving them into the sea. Loss of this ecosystem, coupled with climate change pose serious risk to the survival of S. mitranus. Our study was carried out in two tiers. In the first we set out to estimate dune-dependent population densities, while in the second tier of the study we observed sandfish activity in relation to soil temperature. Sandfish (106) were captured and tagged from 5 terrestrial Barchan dunes in Qatar over a period of 10 months. The captured sandfish ranged from 6 to 29 cm in length and, weighed between 2 and 47 g. Sandfish population estimates were generated for 3 large dunes (Slip face area 1.7 × 104 −  2.5 × 104 m2) and ranged from 30–92 individuals while survival probability ranged from 0.39–0.76 per dune, respectively. Population size (R2 = 0.645) and survival probability (R2 = 0.953) were positively correlated with insect abundance within each dune. Sandfish were observed on the surface of sand dunes at soil temperatures of 35 to 55°C. However sandfish were absent at the mean soil temperature of 44.7°C and present at the mean soil temperature of 43.5°C, a small difference of 1.2°C between the 2 means. Heating of the sandfish significantly affected their ability to carry out activities such as foraging, traveling and interacting. This is the first attempt at creating population baselines and understanding the ecology of S. mitranus in the Barchan dunes of Qatar. Our results may be used to inform environmental management policies in order to preserve this fragile ecosystem.