Premium
Size and Age Structure of Anadromous and Landlocked Populations of Rainbow Smelt
Author(s) -
O'Malley Andrew J.,
Enterline Claire,
Zydlewski Joseph
Publication year - 2017
Publication title -
north american journal of fisheries management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 72
eISSN - 1548-8675
pISSN - 0275-5947
DOI - 10.1080/02755947.2016.1264508
Subject(s) - fish migration , biology , otolith , smelt , population , landlocked country , fishery , population size , abundance (ecology) , ecology , fish <actinopterygii> , demography , sociology , political science , law
Rainbow Smelt Osmerus mordax are widely distributed in both anadromous and landlocked populations throughout northeastern North America; abundance, size at age, and maximum size vary widely among populations and life histories. In the present study, size at age, von Bertalanffy growth parameters, population age distributions, and precision and bias in age assessment based on scales and sectioned otoliths were compared between ecotypes and among populations of Rainbow Smelt. To compare the ecotypes, we collected spawning adults from four anadromous and three landlocked populations in Maine during spring 2014. A significant bias was identified in only one of four scale comparisons but in four of seven otolith comparisons; however, a comparable level of precision was indicated. Anadromous populations had larger and more variable size at age and von Bertalanffy growth parameters than landlocked fish. Populations were composed of ages 1–4; six populations were dominated by age‐2 or age‐3 individuals, and one population was dominated by age‐1 fish. These data suggest the presence of considerable plasticity among populations. A latitudinal gradient was observed in the anadromous Rainbow Smelt, which may show signs of population stress at the southern extent of their distribution. Received March 25, 2016; accepted November 16, 2016 Published online February 27, 2017