Utilization of artificial alternative habitat by waterbirds in Shankou Mangrove National Nature Reserve,Guangxi,southern China
Waterbirds are an important component of the wetland ecosystems.Waterbirds can be used as biological indicators because they are highly sensitive to environmental changes.Shankou Mangrove National Nature Reserve of Guangxi,southern China is an important stopover site for migrant birds along the East Asian-Australasian Fly-way.Due to the loss of natural wetlands,more and more waterbirds are forced to choose artificial wetlands as their alternative habitats.From 2016 to 2021,we investigated the richness and abundance of birds in four main habitats,including aquaculture pond,salt pan,grassland and farmland,to explore the utilization of alternative habitats by waterbirds in the reserve.The results showed that:(1)A total of 13 dominant and common waterbird species were found in the four alternative habitats,with the species richness in aquaculture ponds being the highest,and lowest in farmland habitat.(2)The diversity index and the abundance of waterbirds were dominated in aquaculture pond and salt pan habitats.(3)The generalized linear model showed significant differences in habitat utilization among waterbirds of different taxa.In conclusion,alternative habitats,especially the aquaculture pond and salt pan,play an important role in maintaining the waterbird populations in the reserve.The artificial alternative habitats should receive sufficient attention and effective protection in the future.