Host-Size Selection by Parasitic Sea Lampreys
- 1 September 1991
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 120 (5) , 637-643
- https://doi.org/10.1577/1548-8659(1991)120<0637:hsbpsl>2.3.co;2
Abstract
When 171 sea lampreys Petromyzon marinus were each offered a onetime choice of one large and two small lake trout Salvelinus namaycush, the ratio of their attacks (49.1%:27.5%: 23.4%) was similar to the ratio of host surface areas (51.4%:26.3%:22.3%) in laboratory tests conducted over 9 months in 1988–1989. When the smallest offered host was 560 mm total length (TL) or shorter, sea lampreys attacked the smallest host less often and the largest host more often than expected (N = 39) under assumptions that attacks would be either equal among the hosts (numbers-dependent hypothesis) or proportional to the hosts' surface areas (area-dependent hypothesis). When the smallest host was 615 mm TL or longer, observed attacks (N = 132) did not differ significantly from the number of attacks expected by either the numbers-dependent or the area-dependent hypothesis; however, the largest lake trout was almost always attacked more often than either of the smaller fish. These results are similar to field observa...Keywords
This publication has 0 references indexed in Scilit: