152 
Fishery Bulletin 117(3) 
Table 1 
Summary of key information from previous studies of the fecundity of rainbow smelt (Osmerus mordax ) in coastal waters of 
Massachusetts and Canada and in the Great Lakes. Data provided are location, type of population, total number of samples 
(n), and ranges for size, measured as millimeters in total length (TL), and fecundity, measured as the number of mature oocytes 
prior to spawning. 
Fecundity 
Citation Location Type n Size (mm TL) (no. of oocytes) 
McKenzie, 1964 
New Brunswick 
Anadromous 
9 
127-209 
8500-69,600 
Clayton, 1976 
Massachusetts 
Anadromous 
11 
127-204 
7038-44,241 
Chen, 1970 
Grande Riviere, Quebec 
Anadromous 
48 
160-225 
21,390-75,570 
Bailey, 1964 
Lake Superior 
Landlocked 
10 
185-224 
21,534-40,894 
Chen, 1970 
Matamek Lake, Quebec 
Landlocked 
64 
202-280 
14,269-75,944 
Chen, 1970 
Lake Erie, Ontario 
Landlocked 
93 
115-194 
2700-37,520 
Chen, 1970 
Lake Ontario, Ontario 
Landlocked 
172 
109-256 
4766-100,780 
Luey and Adelman, 1984 
Lake Superior 
Landlocked 
208 
145-225 
4323-50,418 
In response, a regional conservation plan for rainbow 
smelt in the Gulf of Maine was developed and documented 
range-wide declines in harvest records for rainbow smelt 
(Enterline et al., 2012). Similar concerns have been 
expressed for fisheries and populations of rainbow smelt 
in Canada (Trencia et al., 2005; Verreault et al., 2012). 
Anadromous rainbow smelt reproduce during spring 
spawning runs in freshwater riffles a short distance 
above tidal influence (Kendall, 1926; McKenzie, 1964; 
Murawski et al., 1980; Chase 1 ). Female rainbow smelt 
deposit demersal, adhesive eggs that incubate for 1-4 
weeks, depending on water temperature (McKenzie, 
1964; Chase et al. 2 ), and hatched larvae are transported 
to estuarine waters. Female rainbow smelt complete 
spawning in 1-4 nights, whereas males remain longer 
on spawning grounds (Marcotte and Tremblay, 1948; 
Murawski et al., 1980). This brief female spawning period 
is consistent with reports that female rainbow smelt pos¬ 
sess a single set of mature oocytes, with no differences in 
oocyte size and maturity among ovary locations (Chen, 
1970; Clayton, 1976). 
Rainbow smelt occur in anadromous and landlocked pop¬ 
ulations in northeastern North America, with differences 
in life history. Landlocked rainbow smelt are present nat¬ 
urally in some coastal lakes; however, most populations 
were introduced to the Great Lakes and many smaller 
watersheds early in the 20th century (Van Oosten, 1937; 
Evans and Loftus, 1987; and Mercado-Silva et al., 2006). 
Landlocked rainbow smelt grow slower and are smaller 
than anadromous rainbow smelt, and they mature at an 
older age (Bailey, 1964; Luey and Adelman, 1984; O’Malley 
et al., 2017). The maturity schedule and fecundity of land¬ 
locked rainbow smelt have been related to high recruitment 
variability (O’Gorman et al., 1987; Gorman, 2007; Stritzel 
Thomson et al., 2011), and comparable information on 
2 Chase, B. C., J. H. Plouff, and M. Gabriel. 2008. An evaluation 
of the use of egg transfers and habitat restoration to establish 
an anadromous rainbow smelt spawning population. Mass. Div. 
Mar. Fish. Tech. Rep. TR-33,16 p. [Available from website.] 
reproduction of anadromous rainbow smelt is not available. 
Fecundity has been reported for anadromous populations of 
rainbow smelt, but with small sample sizes (combined num¬ 
ber of samples [/?]=68, among 3 studies: McKenzie, 1964; 
Chen, 1970; and Clayton, 1976). Fecundity of landlocked 
rainbow smelt has been studied in the Great Lakes (Bailey, 
1964; Chen, 1970; Luey and Adelman, 1984), with fecundi¬ 
ties ranging from 2700 to 100,780 eggs (Table 1). 
With a paucity of population data and gaps in basic 
life history information for anadromous rainbow smelt, 
limited support is available for management decisions 
on population status and vulnerability. Here, we aim to 
advance the understanding of the reproductive life history 
of rainbow smelt with improved estimates of fecundity, of 
size and age at maturity, and of length and age composi¬ 
tion during spawning runs. We also estimated mortality 
and eggs per recruit and compared the results to historical 
data for rainbow smelt. A key assumption was that the 
apparent changes in abundance of rainbow smelt would 
be reflected in truncated age structure and increasing 
mortality. To achieve these objectives, rainbow smelt were 
sampled as part of an inshore winter trawl survey prior to 
spawning and later in 4 coastal rivers in Massachusetts 
during their spawning migrations. 
Materials and methods 
Historically, the range of rainbow smelt once extended as 
far south as Delaware Bay (Scott and Crossman, 1973), 
but more recent information indicates that populations 
south of Massachusetts are extinct or undetectable (Fried 
and Schultz 3 ; Enterline et al., 2012). For this study, anad¬ 
romous rainbow smelt were sampled near the present 
southern extent of their range in marine waters and 
3 Fried, H. A., and E. T. Schultz. 2006. Anadromous rainbow smelt 
and tomcod in Connecticut: assessment of populations, conser¬ 
vation status, and need for restoration plan. Univ. Conn., Dep. 
Ecol. Evol. Biol., EEB Article 18,262 p. [Available from website.] 
