Analyzing the relative habitat use by Siberian cranes on migratory stopover sites: A traditional wetland species switching to croplands for food resources

Abstract

Aims: Siberian crane (Grus leucogeranus) is a migratory, endangered species that uses the Songnen Plain as a main stopover area. Traditionally a wetland species, today most populations of Siberian cranes feed and rest during migratory stopovers in fields of corn (Zea mays). By examining the causes of this change in stopover habitat use, we can provide better protection for and potentially recovery of this declining species. Methods: We recorded the numbers of Siberian cranes and both food resource and habitat usage on stopover sites on the Songnen Plain from September 2020 to November 2021 in the study area. These data were collected and analyzed using Google Earth, ArcGIS 10.7. Results: Of the total number of Siberian cranes we observed, 72.7% were feeding on farmland, which was 2.66 times more than that of wetland habitats. Farmland has become the main feeding habitat for Siberian cranes. The total energy provided by farmland was 1.24-2.79 times as much as that provided by wetlands based on different harvesting methods, and the energy intake of Siberian cranes in farmland was about 1.56 times that of wetland. The daily feeding budget of Siberian cranes in farmland was 53.5% of their total time, which was 1.67 times more than that in wetlands. The feeding

Response of Siberian Cranes (Grus leucogeranus) to Hydrological Changes and the Availability of Foraging Habitat at Various Water Levels in Poyang Lake

“…Over the recent years, the recorded number of Siberian cranes has steadily increased, reaching 2900 by 2020 [57]. This upward trend suggests that artificial habitats offer certain advantages as a supplementary food source, providing relatively rich food resources and posing fewer feeding challenges [58]. Despite the rebound in Vallisneria abundance within natural habitats, the presence of these advantages consistently prompts certain Siberian cranes to choose artificial habitats.…”

“…Depending on water levels, Siberian cranes can adaptively adjust their proportion of use between natural and artificial habitats to enhance their overall suitability [59]. In summary, the dominant factors influencing foraging habitat selection by Siberian cranes were the abundance of food and the availability of foraging habitat [58].…”

Carrying capacity of black‐necked cranes in Dashanbao National Nature Reserve, China

“…Current studies on crane feeding on invertebrates have focused on describing species (Reinecke and Krapu 1986, Bergeson et al 2001, Barzen et al 2018a, abundance (Avilés et al 2002, Liu et al 2019, and nutrition (Nelson et al 1996) and have not analyzed their intake rates. There are more studies related to cranes feeding on aquatic plant tubers (Burnham et al 2017, Gao et al 2022, but there are a lack of studies on the intake rate of potatoes. Our study on the intake rate of black-necked cranes on invertebrates and potatoes can provide some reference for the study of crane feeding on diverse food.…”