Habitat Selection Of The Red-Crowned Cranes In Breeding Period During The Initial Stages Of Wetland Recovery In Zhalong Nature Reserve Based On "3S" Technology

In Zhalong Nature Reserve, a research on habitat selection, nest-site selection regression model and nest-site habitat assessment of Red-crowned Cranes (Grus japonensis) during the different stages of the breeding period was conducted from March to August in 2002 to 2005 by the survey methods of fixed-spot observation, GPS positioning, plot sampling measurement, factor measurement, scan sampling method, focus sampling method and the date proceeding methods of significant test method, variance analysis method, factor analysis, linear regression analysis, distribution distance index and combining Arcview GIS version 3.1 software, Erdas imagine 8.5 software, Landsat 5 TM. The results are as follows:(1) During pre-breeding period, Red-crowned Cranes prefer to select single type of habitat for feeding, and focus mostly on water field especially reed marsh {Phragmites australis mire) (88.89%). Food factor plays a crucial role during the course of feeding habitat-selection, second factor is concealment factor, next is water factor and identification factor. Wild and semi-domestic Red-crowned Cranes both feed at reed marsh habitat with long distance to high frequency human activity area (1.93km) and burned sites (1.61km), and that the two colony have the obvious niche separation in feeding micro-habitat. Wild Red-crowned Cranes prefer to select high altitude (141. 5m), the residual reed cluster with lower quality, long distance to lower frequency human activity area (0.56km), and semi-domestic Red-crowned Cranes is just reverse.(2) During breeding period, Red-crowned Cranes mostly prefer to select reed marsh for nesting (86.94%). It takes on specific and non-randomicity about habitat selection of Red-crowned Cranes. The essential factor including vegetation type, lakeside, distance to high frequency human activity area and distance to lower frequency human activity plays a crucial role during the course of nest-site selection, second factor is fostering factor, next is nest-material factor and incubating factor. Wild and semi-domestic Red-crowned Cranes prefer to select the same habitat type for nesting, but it exits distinct niche separation on nest-site micro-habitat selection. Wild Red-crowned Cranes prefer to select habitat with long distance to high frequency human activity area (2.25km) and lower frequency human activity area (0.79km), and semi-domestic Red-crowned Cranes is just reverse.The regression model of nest-site selection on Red-crowned Cranes was simulated, namely y =0.570x₁+0.324x2+0.268x3+0.282x4+0.229x5-0.201x₆-0.454x₇+ 0.554x₈+ 0.0193x₉. The results about spatial patterns of nests and territory on Red-crowned cranes shows that I₂₀₀₂=2.1401>2, spatial patterns of nests about Red-crowned cranes during the breeding period in 2002 in Zhalong Nature Reserve belong to clumped dispersion; I₂₀₀₃=2.0478>2, in 2003 also clumped dispersion; I₂₀₀₄-1.8379<2, in 2004 uniform dispersion. If the territory shape of all breeding Red-crowned cranes is round and its territory area is equal, then territory area on Red-crowned Cranes in Zhalong Nature Reserve during the incubating period is 0.863 ± 0.389km .The results of nest-site habitat assessment on Red-crowned Cranes is HSl2002=0.4927, HSI2oo3=O.4888, HSI2004=0.5593, HSI2oo5=O.6O89. The results indicate that since successive years irrigating in 2002, it exists a transformation trend from clumped dispersion to uniform dispersion about nests spatial patterns of Red-crowned Cranes during the incubating period in Zhalong Nature Reserve, and territory area on Red-crowned Cranes in Zhalong Nature Reserve during the incubating period is diminishing, and the wetland habitat quality of Zhalong wetland takes on the trend of meliorating.The decision results of Landsat 5 TM show that in 2004, Zhalong Nature Reserve has 39646.3 ha of suitable nesting habitat, 12354.4 ha of potential nesting habitat. If regarded 126 ha as the territory area of Red-crowned Cranes, then the suitable habitat has able to hold 191 pairs breeding Red-crowned Cranes, and then the potential habitat has able to hold 46 pairs breeding Red-crowned Cranes.During the breeding period, it exist specific and non-randomicity about feeding habitat selection of Red-crowned Cranes. The guarding factor (including whether or presence surplus reed cluster, distance to high frequency human activity area and distance to nest-site) and energy factor (including vegetation type, water depth, whether or presence lakeside and distance to lower frequency human activity area) plays a crucial role during the course of feeding habitat selection. Red-crowned Cranes prefers to select. Red-crowned Cranes prefer to select field with definite distance to nest-site (0.68km), away from high frequency human activity area (2.10km), close with lower frequency human activity area (0.40km), no presence of surplus reed cluster in the range of 100m, the presence of lakeside, water depth (17.8cm) for feeding.(3) During the pre-fostering period, Red-crowned Cranes prefer to select less reed marsh area with better shelter around nest-site for fostering; During the post-fostering period, Red-crowned Cranes prefer to select open Carex marsh with better shelter reed marsh and definite water depth for fostering.