Do birds mate for life? If so, what birds and why?

Do Birds Mate For Life - What Birds?

Do birds mate for life? If so, what birds and why?

Answer: Yes and... No

A discussion of whether birds mate for life has to begin by

having an understanding of what we mean by the term "mating for life".

For some, having a mate for life means, marriage for 40 - 60 years, partner passes, and surviving mate lives with fond memories until death. Never to partner with another.

Even this is open to interpretation, intent needs to be considered. Does not the widow/widower plan for a lifelong partnership even if the spouse passes prematurely? Does a new partnership negate the intent of the first?

If mating for life means one partner in a lifetime to you, then there are few birds that fit into this category. Those birds that do fit this category are the ones that die, as the surviving bird will attempt to find a new mate. Some within the same nesting season.

Others will forage for food through the breeding season, joining flocks in the fall. Still, others will help feed and raise the young of other pairs, but all will attempt to find a new mate.

Most of our North American birds do not mate for life. Rather, most pair bonds are formed for a single season. Those birds that pair for a season are referred to as monogamous pairs. Monogamy is one male bird with one female bird through a single nesting cycle.

The pair may stay together raising a single brood and then change partners for a second brood in the same season. Still they are considered monogamous.

Other pair bonds may be formed and last over several seasons. Doves, robins, and others are on this list. Oftentimes, these birds are considered as mating for life. Even though their average life spans may range from a year and a half to several years. Despite whether they mate again after one dies.

Bird Monogamy

When we speak of birds and monogamy, we are not referring to faithfulness. First year mortality rates are very high with regards to our small songbirds and reproduction is a primary goal.

The truth is, DNA evidence points to a high percentage of promiscuity. Many females lay clutches that are determined to be from different males.

This in turn suggest, males may breed with more than one female even though a pair bond may have been formed with another female.

Birds That Mate For Life

Several large birds are considered as mating for life. Among them are: swans, geese, eagles, and some owls.

Why birds mate for life is not as romantic as one may wish. When you consider the time needed to migrate, establish territories, incubation and raising young, you'll realize that the extra time and energy needed for attracting a mate would minimize reproductive time.

The Bald Eagle for example, spends just over a month incubating the eggs and 2 1/2 to 3 months raising their young in the nest. Establishing lifelong pair bonds works to their advantage. Whether this adaptation evolved over time or always has been, I do not know.

Summary

I suppose the question of whether a bird mates for life comes from wondering what will happen should one bird die. Many believe that birds mourn the loss of their mate, never to mate again.

This just isn't true. Wild birds will always attempt to find new mates.

Whether a bird mates for a single brood or 40 years, our job is to provide the best environment for them to be successful at what they're attempting to do - raising more birds for us to enjoy.