Data from: Pair bonds, reproductive success and rise of alternate mating strategies in a social carnivore.

Monogamy is commonly observed across a wide variety of species and taxa
and arises when young are altricial, parental investment in young is high,
and mate monopolization is generally not possible. In such species, pairs
may bond for multiple breeding seasons while successfully rearing young.
Individuals, however, may attempt to bypass the dominant mating strategy
particularly when breeding opportunities are limited. Currently, we do not
know how pair bond duration affects the efficacy of alternative mating
strategies in populations with a monogamous mating system. Additionally,
inferences about pair bond effects on reproductive success (i.e., both
clutch size and recruitment) are largely limited to long-lived birds and
little is known about effects on mammalian cooperative breeders. I used
genetic sampling and pedigrees to examine the effects of pair bond
duration on reproductive success (i.e., litter size, recruitment) and
mating strategies in a population of gray wolves (Canis lupus) in Idaho
USA. There was a positive, marginally significant relationship between
pair bond duration and apparent survival of offspring. Increased pair bond
duration was also associated with a dampening in the prevalence of other
alternative mating strategies such as sneaker males and polygamy. The
selective advantage of alternative mating strategies are a combination of
population, group (for applicable species), individual, and social
influences such as pair bonds. The distribution of pair bonds in a
monogamous population affects the selective advantage, and hence
frequency, of various mating strategies observed.