Environmental Biology of Fishes

, Volume 15, Issue 2, pp 119–129

Reproductive tactics and fertilization success of mature male Miyabe charr, Salvelinus malma miyabei

  • Koji Maekawa
  • Hiroshi Onozato
Article

DOI: 10.1007/BF00005427

Cite this article as:
Maekawa, K. & Onozato, H. Environ Biol Fish (1986) 15: 119. doi:10.1007/BF00005427

Synopsis

Spawning behaviour, fertilization success and reproductive ecology of stream-resident and lake-run male Miyabe charr, Salvelinus malma miyabei, were studied under natural and artificial conditions. In Shikaribetsu Lake, Japan, the ratio of the two types of males is approximately 1:1, estimated by weir data. The majority of stream-resident males mature sexually at 2+ years of age, while the lake-run males begin to mature at 4+. In contrast to the large-bodied lake-run males, which paired with females, the smaller stream-resident males attempted to fertilize eggs by ‘streaking’ into the nest. We demonstrated through electrophoretic techniques that stream-resident males were able to fertilize eggs by streaking. Under artificial conditions, the estimated maximum proportion of eggs fertilized by a single stream-resident male was about 16.8. The evolutionary stability of the charr's dual mating system may be explained by Gross's theory for alternative life-history evolution, although further testing is necessary.

Keywords

Stream resident malePrecocityStreakerFertilization successMixed ESSSalmonid

Copyright information

© Dr W. Junk Publishers 1986

Authors and Affiliations

  • Koji Maekawa
    • 1
  • Hiroshi Onozato
    • 2
  1. 1.Department of AnatomySchool of Dentistry, Hokkaido UniversitySapporoJapan
  2. 2.Nanae Fish Culture Experimental Station, Faculty of FisheriesHokkaido UniversityHokkaidoJapan