Research on the response mechanisms of the Siberian crane population to
hydrological temporal and spatial variations in transit stopover sites
Abstract
The Siberian crane (Grus leucogeranus), a critically endangered species,
is used as an indicator species for ecosystem stability because of its
sensitivity to the environment. The distribution of Siberian cranes has
shown dramatic fluctuations on an order of magnitude at the main
stopover site (Jilin Momoge National Nature Reserve) since the present
century, which poses a great challenge to the conservation of endangered
species. Research on the threshold values of key factors of the Siberian
crane in stopover habitats and the relationship between the Siberian
crane and hydrological temporal and spatial fluctuations can promote
endangered species conservation. The response of population changes and
distribution patterns of Siberian cranes to hydrological temporal and
spatial patterns of wetlands was analyzed from 1984 to 2020. The results
showed that population changes and distribution patterns of Siberian
cranes were highly correlated with hydrological temporal and spatial
patterns in the study area, and their variation trend was the same.
However, there were obvious stage migration changes in the core activity
area of the Siberian crane (1984-2000, 2001-2010 and 2010-2020). The
habitat characteristics of fragmentation, dispersion and complex shape
of water bodies changed from steady to dramatic fluctuations and then
leveled off in the core activity area of Siberian cranes during the 37
years of migration transit. This was closely related to the early
agricultural reclamation and the later ecological water replenishment
project in the study area. In addition, the trend of the water pattern
index of the spatial distribution of Siberian crane active habitat was
also closely related to their habitat selection preference. When the
perimeter area fractal dimension of water (1.27-1.30), landscape
division index (0.73-0.95) and aggregation index (80.97-91.36) are
within a certain stable threshold, the stopover habitat of the Siberian
crane is suitable.