The effect of climate change on the distribution of Caspian red deer (Cervus elaphus maral) in Central Alborz Protected Area

Climate change along with human development created additional pressure on ecosystems, so in many cases it has caused a decrease in biodiversity. Global climate change continues as a global crisis. Climate change does not affect all habitats and species equally. Rather, large species are more affected by climate change and habitat change and are more vulnerable than other species. Also, studies show that the countries of the Middle East have been severely affected by the effects of climate change. Large herbivores, especially red deer (Cervus elaphus), are not only affected by habitat changes resulting from climate change, but also the increase in temperature has reduced the survival rate of calves and impaired reproduction. The Caspian red deer in Iran has lost a lot of its population under the influence of habitat destruction and illegal hunting, and today the remaining population tolerate additional pressure from climate change. Central Alborz Protected Area is considered as a main breeding habitat of Caspian red deer, which is affected by human development and climate change today.

In this study, in order to investigate the impact of climate change on the red deer population, temperature and precipitation data of two meteorological stations, Nowshahr in the lower elevations, and Baladeh in the southern elevations, were used. Also, presence and non-presence points of the species were collected random transects direct observation, as well as pictures of camera traps.

Using 19 climate parameters to evaluate habitat suitability in the future, it revealed that continuation of the climate change process in four optimistic to pessimistic scenarios using five MaxEnt, RF, ANN, GLM, MARS algorithms, the suitability of low altitude areas in the sectors of north and east will be reduced, and will be increased towards to highlands in southwest. The results showed that the parameters of average annual temperature, average daily temperature, average temperature of the dry season, average temperature of the hottest season, annual rainfall, rainfall in the wettest season, and rainfall in the hottest season have an effective role in determination of the habitat suitability of the species. The results of the climate data showed that the altitude plays an effective role in reducing the effects of climate change, so that the climate change in the downstream areas has a significant intensity compared to the high areas. According to the change of habitat suitability resulting from the continuation of the climate change, Kojoor forest zone shows the relative stability of desirability for the studied species in the present and future, but the Kheyrud forest road with a total length of more than 50 km is located in the depth of this area, where the traffic of vehicles of herders, ecotourists and especially illegal hunters have facilitated access to this habitat, which is the most main threat to survival of red deer in this habitat.

With the continuation of climate change and its effects on the habitat in the future, it is expected that female deers will be observed in unsafe parts of the habitat. Therefore, for conservation of the Caspian red deer population in the central Alborz Protected Area, robust management measures are needed based on created habitat changes in the future.