Nedzinskas, V. 1973. [A contribution to the ecology of the Lithuanian popula- 

 tion of Cygnus olor . ] Zool. Zh. 52: 1360-1366. [In Russian with English 

 summary. ] 



Nilsson, L. 1973. [The breeding population of the Mute Swan Cygnus olor in 

 the provinces of Scania and Blekinge, south Sweden in 1972.] Var Fagel- 

 varld 32: 115-119. [In Swedish with English summary.] 



Reichholf, J. 1973. Die Bestandsenwicklung des Hockerschwans Cygnus olor und 

 seine Einordnung in das Okosystem der Innstauseen. Anz . Ornithol. Ges . 

 Bayern 12: 15-46. [In German with English summary.] 



Trapp, J. L. 1973. Mute Swans entangled in fishing line. Jack-Pine Warbler 

 51: 91-92. 



1972 



Arnold, E. 1972. Mute Swan feeding in field. Atl. Nat. 27: 128. 



Bloch, D. and L. Kraul. 1972. Residues of polychlorinated biphenyls (PCB) 



and organochlorine insecticides in eggs from Mute Swan ( Cygnus olor ) and 

 Pochard ( Aythya ferina ). Acta Vet. Scand. 13: 588-590. 



Cramp, S. 1972. One hundred and fifty years of Mute Swans on the Thames. 

 Wildfowl 23: 119-124. 



Reynolds, C. M. 1972. Mute Swan weights in relation to breeding performance. 

 Wildfowl 23: 111-118. 



Willey, C. H. and B. F. Halla. 1972. Mute Swans of Rhode Island. Rhode Is- 

 land Dept . Nat. Resourc. Wildl. Pamphl. No. 8. 47 pp. 



Wood, R. and W. L. Gelston. 1972. Preliminary report: the Mute Swans of Mich- 

 igan's Grand Traverse Bay region. Mich. Dept. Nat. Resourc. Rept . No. 

 2683. 6 pp. 



1971 



Minton, C. D. T. 1971. Mute Swan flocks. Wildfowl 22: 71-88. 



1970 



Bloch, D. 1970. Knopsvanen ( Cygnus olor ) som kolonifugl i Danmark. [The Mute 

 Swan Cygnus olor breeding in colony in Denmark.] Dan. Ornithol. Foren. 

 Tidsskr. 64: 152-161. [In Danish with English summary.] 



Brooke, M. de L. 1970. Some aspects of Mute Swan movement and mortality. 

 Cambridge Bird Club Rept. 44: 44-47. 



Gelston, W. L. 1970 ms. A preliminary report on the Traverse City Mute Swan 

 flock. Mich. Dept. Nat. Resourc, Lansing, MI. (Mimeo) . 



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