Heart Worm, Sarconema eurycerca, Infection in Whistling Swans, Cygnus columbianus, in Chesapeake Bay

¹ Department of Pathobiology, Johns Hopkins University, Baltimore, Md.

Seven Whistling Swans from the eastern shore of Chesapeake Bay, Maryland, were examined for parasites during the spring, 1967, and all contained nematodes, Sarconema eurycerca, in the myocardium. The mean number of worms, most of which were female worms, was 12 per host. Both mature and immature worms were found in juvenile and adult hosts. Dimensions of these nematodes agreed with those given by Wehr (1939) in the original description of S. eurycerca, as well as with those specimens from a Whitefronted Goose from the Northwest Territories. This nematode is widely distributed and has been found in 3 species of swan and 2 species of goose. The life cycle is unknown.

S. eurycerca has been implicated as a cause of death among wild and captive swans and its damage to the heart is known to be severe. However, since the numbers of birds in the area do not appear to be decreasing, light infections may not be pathogenic.