Population trends, threats, and conservation recommendations for waterbirds in China

Abstract

Background: China is one of the countries with abundant waterbird diversity. Over the past decades, China's waterbirds have suffered increasing threats from direct and indirect human activities. It is important to clarify the population trends of and threats to waterbirds as well as to put forward conservation recommendations. Methods:We collected data of population trends of a total of 260 waterbird species in China from Wetlands International database. We calculated the number of species with increasing, declining, stable, and unknown trends. We collected threatened levels of waterbirds from the Red List of China' s Vertebrates (2016), which was compiled according to the IUCN criteria of threatened species. Based on literature review, we refined the major threats to the threatened waterbird species in China.Results: Of the total 260 waterbird species in China, 84 species (32.3%) exhibited declining, 35 species (13.5%) kept stable, and 16 species (6.2%) showed increasing trends. Population trends were unknown for 125 species (48.1%). There was no significant difference in population trends between the migratory (32.4% decline) and resident (31.8% decline) species or among waterbirds distributed exclusively along coasts (28.6% decline), inland (36.6% decline), and both coasts and inland (32.5% decline). A total of 38 species (15.1% of the total) were listed as threatened species and 27 species (10.8% of the total) Near Threatened species. Habitat loss was the major threat to waterbirds, with 32 of the total 38 (84.2%) threatened species being affected. In addition, 73.7% (28 species), 71.1% (27 species), and 57.9% (22 species) of the threatened species were affected by human disturbance, environmental pollution, and illegal hunting, respectively. Conclusions:We propose recommendations for waterbird conservation, including (1) strengthening conservation of nature wetlands and restoration of degraded wetlands, (2) enhancing public awareness on waterbird conservation, (3) improving the enforcement of Wildlife Protection Law and cracking down on illegal hunting, (4) carrying out longterm waterbird surveys to clarify population dynamics, (5) restoring populations of highly-threatened species through artificial intervention, and (6) promoting international and regional exchanges and cooperation to share information in waterbirds and their conservation.

Reducing human pressure on farmland could rescue China’s declining wintering geese

“…Given that habitat loss is identified as the top threat to Chinese wintering waterbirds [21], not being able to explore alternative farmland food resources in the core wintering region likely contributed to the considerable population reduction of Chinese wintering geese. Setting aside farmland refuges, especially at the heavily disturbed key wintering site, the Yangtze River Floodplain, is a promising conservation measure for China's wintering geese.…”

A potential distribution map of wintering Swan Goose (Anser cygnoides) in the middle and lower Yangtze River floodplain, China

“…Wetlands play an important role in ecological diversity, and waterbirds are key bio-indicators for wetland health assessments (Wang et al 2018). Many natural wetlands have been lost in China over the last 50 years with the rapid economic development that has taken place in the 20th century (An et al 2007).…”

“…Over the last several decades, policymakers and environmental managers have implemented numerous measures for waterbirds conservation in China, such as building up national nature reserves, designating key wetlands as Ramsar Sites (those designated as internationally important wetlands), conducting long-term waterbird surveys, and carrying out public education initiatives (The State Forestry Administration 2015; Zeng et al 2018). To a certain extent, these efforts have all been successful; however, waterbirds still face increasing pressure from many different directions (Yang et al 2011;Wang et al 2017Wang et al , 2018. Thus far, the conflict between waterbirds conservation and economic development has not only been a local issue but a national concern (Cao and Fox 2009).…”

Rectification of Abnormal Migration Recorded in Hand-reared Red-crowned Cranes (Grus japonensis)

“…Artificial interventions are encouraged in protecting endangered species with small population size (Wang et al 2018). Inexperienced migrants of some bird taxa (e.g., passerines and raptors) may rely on inherent navigation system to find correct way to wintering area for their first migration (Berthold 2004;Thorup et al 2007;Mellone et al 2016).…”