Effects of overripening on spawning behaviour and reproductive success of Atlantic salmon females spawning in a controlled flow channel

Abstract

The influence of overripening on salmonid egg quality has often been described in artificial breeding. However, no information exists on the impact of this factor on fish reproducing naturally, although it is likely to be critical, especially in disturbed environments. Pairs of Atlantic salmon in which the size of the male and the female was evenly matched were released in a spawning channel from 1 to 12 days after ovulation. Handling did not affect egg quality.Overripening had a negative effect on egg viability. Egg mortality, infertility and malformations increased with the number of days after ovulation. In females which had just matured, 16·7% of their recovered eggs were dead, 3·1% were unfertilized and 1·7% were malformed, as compared to 25·4, 9·7 and 5·4%, respectively, in females that had been mature for at least a week. Overripening played a role in both female spawning behaviour and capacity to spawn, as females which had been mature for over a week released their eggs more quickly while they retained more ova in their abdominal cavity than early spawning females. Thus, in studies of reproductive behaviour and in particular of sexual selection, it is critical to take into account the maturation status of females since the duration of spawning activity is used by various authors to determine female sexual motivation. Alternatively, overripening may decrease the female selectivity for mates. 1998 The Fisheries Society of the British Isles

Effects of delayed fertilization on embryo viability in walleye Sander vitreus (Mitchill): the role of maternal effects

“…for some species (Mollah & Tan, 1983;Formacion et al, 1993;Bromage et al, 1994;Suquet et al, 1999), within a few days for others (Koya et al, 1994;Ciereszko et al, 2000), or may only occur after a week or longer in others (Hay, 1986;Fitzpatrick et al, 1987;de Gaudemar & Beall, 1998). Results of the current study and those of an earlier study on walleye ova storage (Rinchard et al, 2005) indicate that walleye are probably intermediate along this continuum.…”

“…Thus, the changes associated with the overripening process appear to influence not only fertilization but also later development. This also appears to be the case in rainbow trout Oncorhynchus mykiss (Walbaum) (Springate et al, 1984) and Atlantic salmon Salmo salar L. (de Gaudemar & Beall, 1998). In some species, the effects of overripening may actually be more pronounced on later development than on fertilization.…”

Male and female contributions to behavioral isolation in darters as a function of genetic distance and color distance

“…; Bromage et al. ; de Gaudemar and Beall ), and preliminary data indicate that this is the case in darters (in prep.). The optimal strategy for females may be to spawn quickly after ovulation.…”

Evolutionary causes and consequences of sequential polyandry in anuran amphibians

“…This is because ova viability in vertebrates is known to decrease rapidly with increasing time since ovulation (e.g. Atlantic salmon, Salmo salar ) (DeGaudemar & Beall, 1998). Furthermore, the longer eggs are retained after oviposition the greater the chance that a female's oviducts will become egg bound (dystocia), which will elevate mortality risk and compromise future breeding opportunities (Noble & Aronson, 1942).…”

“…In anurans with sequential polyandry, the interval between ovulation and spawning can be protracted due to the time required to locate successive mates. In many external‐fertilizing salmonid fish it is known that forced delays in spawning can lead to the over‐ripening of eggs, and subsequently reduced fertilization success or a higher incidence of egg malformation and reduced offspring survival (DeGaudemar & Beall, 1998). Assuming that similar challenges face anurans, sequential polyandry may lead to the evolution of more robust eggs that can be retained by females for extended periods.…”