Sea Lamprey (Petromyzon marinus) Control — Where to From Here? Report of the SLIS Control Theory Task Force

Abstract

Sea lamprey (Petromyzon marinus) control with selective toxicants has reduced sea lamprey abundance in the Great Lakes to levels which permit survival of desirable fish species, but development of alternate and supplemental control methods is essential since chemicals cannot be used indefinitely. The Task Force addressed hypotheses which relate to regulation of sea lamprey numbers during different life history stages and why sea lampreys appear to affect fish stocks differently in various bodies of water. Examination of the information about the various factors that control sea lamprey abundance, both natural and man-made, permitted the Task Force to develop several hypotheses and to indicate areas where additional emphasis or research could produce new or supplementary control methods. Efforts to develop an integrated program of sea lamprey control should be accelerated by development of present promising areas as well as expansion in new directions. Sea lampreys when compared with teleosts exhibit many features of a prototype vertebrate and some unique specializations. Physiological, biochemical, or behavioral differences between lampreys and teleosts may be exploitable for developing control techniques specific to sea lampreys.Key words: sea lamprey, Great Lakes, population control, barrier dams, integrated pest management, buffer species, physiology, teleosts

Microhabitat use by the larvae of cryptic lamprey species in Lethenteron reissneri in a sympatric area

“…Younger larvae of sea lamprey Petromyzon marinus, however, appear to more abundant in sand and gravel than in the silt-detritus habitat preferred by older larvae, and then move to silt-detritus areas as they grow (Lamsa et al, 1980). In the present study, size-dependent variation in habitat was demonstrated for both L. sp.…”

“…Availability of space in the preferred habitat occupied by increasing numbers of immigrants might limit the growth of ammocoetes already present or stimulate further movement into other areas (Lamsa et al, 1980). The sizedependent difference of habitat use found in the present study might be a representation of habitat preference and/ or a result of behavioral interaction.…”

“…N and L. sp. S. Lamsa et al (1980) reported that behavioral interactions, such as aggressive encounters or secretion of inhibitory substances, have not been observed between larvae of different lamprey species. On the other hand, the densities of each size group were not signifi cantly independent from each other, suggesting different habitat uses among them.…”

“…However, some authors have demonstrated that the organic content of a substrate has only a marginal infl uence on the abundance of lamprey larvae (Malmqvist, 1980;Murdoch et al, 1991). Although some lamprey species indicate sympatric distribution, evidence of habitat segregation is rarely reported for sympatric lampreys (Lamsa et al, 1980;Maitland, 1980;Kelly and King, 2001). On the other hand, some authors reported the habitat shift of larval lampreys according to growth (Hardisty, 1986;Sugiyama and Goto, 2002).…”

Alternative Reproductive Behaviors in Lampreys and Their Signifcance

“…Spawning in lakes (Russell et al 1987) and at relatively great depths (Lamsa et al 1980) has been reported, and some lampreys may spawn beneath cover (Cochran and Gripentrog 1992). The sea lamprey has been observed spawning during late summer (Montgomery et al 1983).…”