ORIGINAL RESEARCH
		
		 
	
	
	
		Water on the Fen Mire as a Problem
in the Protection of Globally Threatened
Species: Long-Term Changes
in Aquatic Warbler Numbers
	
	
		Grzegorz Grzywaczewski1, Andrzej Bochniak2, Jarosław Wiącek3,
Paweł Łapiński4, Federico Morelli5,6
		
			
			Pol. J. Environ. Stud. 2017;26(2):613-618