Habitat Suitability Assessment Of Red-crowned Crane In Zhalong Nature Reserve Based On MAXENT Modeling

Wetland is an ecosystem with a high degree of biodiversity, and is one of the most important human living environments. Zhalong wetland, located in northern China, has an important place in the conservation of global biodiversity, especially of the Red-crowned Crane(Grus japonensis) which was listed as a globally endangered species by the IUCN Red List of threatened species(IUCN, 2012). However, in recent decades, human and natural factors have had serious threat the Zhalong wetland on the original landscape pattern, hydrology and vegetation. Habitat loss and deterioration of wetland quality are the main reasons of the reduction of waterfowls, and they are strong influences the health and integrity of waterfowls. Therefore, the study of Red-crowned crane habitat suitability provides scientific basis for protecting rare waterfowl habitat and preserving biodiversity, thereby being considered important in implementing sustainable development of the ecological environment. In this study, the feeding habitat suitability of Red-crowned crane in Zhalong Natural Reserve was performed using the Maximum Entropy(MAXENT) model. This model was implemented using an integration of remotely sensed data(e.g. Landsat TM, EVISAT(HH/HV) images), measured Red-crowned crane points, as well as environmental characteristics(e.g. land cover types, habitat composition, water depth, vegetation cover, distance to residential area, distance to roads, distance to cultivated lands.). The developed MAXENT model with 3S technology provided reference and guidance for potential habitat distribution prediction and habitat suitability assessment of rare and endangered species with limited distribution data. With the rapid development of computer technology and 3S technology, together with the MAXENT model, innovative development in studying bird ecology could be expected. The main results obtained as follows:1. Results showed that the MAXENT model prediction accuracy is higher, the potential of species distribution prediction, environmental factor weighting analysis, and the impact of environmental factors on habitat suitability of quantitative description show the superior performance.2. Through applying the Jackknife variable contribution test, it revealed that among the selected habitat features used for the MAXENT model development, habitat composition was the most importance variable to the habitat suitability assessment of Red-crowned cranes, followed by water depth, land cover type, distance to residential area, distance to roads, and distance to cultivated land.3. Results suggested that the Red-crowned cranes appeared to select areas the reed swamp is indispensable, low-depth of water about 0-50 cm, preferring suit-cover approximately 47.5%-74.5% and far from human activities abound 1 500 m.4. Results of MAXENT model indicated that the geographical area of unsuitable region is approximately 140 420.46 hm2, that of marginally suitable region is approximately 32 843.87 hm2, that of moderately suitable region is approximately 22 544.76 hm2, and that of the most suitable region is about 15 048.27 hm2. The area of suitable feeding habitat(moderately suitable region and most suitable region) of Red-crowned crane was 37 593.03 hm2, accounting for 17.83% of the total protected areas, mainly distributed in the core zone of the reserve.