Monday, February 27, 2012

Reproductive Behavior

The way in which gulls mate is actually quite similar to humans in that monogamy is the accepted way to go! Most seagulls began the reproduction process of selecting a mate at around the age of 4. During this time, male seagulls work to show off in a variety of ways so they will be selected by the females as reproductive mates. Below is an image of two male seagulls taking part in this behavior.

Once a seagull has found her mate, however, their behavior remains pretty calm because all courtship behaviors are complete. Although gulls do settle in colonies or groups, each couple has their own personal plot of land (check out the last post for more information on that!). Divorce does happen on occasion with gulls; however, it is not often and the cost of the break up can persist for a few years after it occurs. The majority of gulls will breed once a year, producing a clutch size of three eggs. After the eggs are born, they being about a month long incubation process. At this point having a reliable mate is essential for seagulls. The parents will take turns incubating the eggs, allowing the their mate to feed.

An interesting fact regarding gulls and their courting behavior is they take part in homosexual mate selection. Similar to elephants and the very familiar Homo sapian, some gulls will select same sex mates. There was a particularly high instance of this off the coast of Santa Barbara. Although it is unclear why exactly gulls take part in this behavior, it possibly has to do with the high female to male ratio on the islands. Studies regarding this behavior continue to find out more about the lesbian seagulls that have caused quite the ruckus in both homosexual and conservative groups. (image)


  1. I wonder if gulls have a higher homosexual percentage than humans. It's so interesting that they turned to that more when there was an uneven sex ratio!

  2. I think it's so cool that they are monogamous when it comes to relationships! It seems like so often in the animal world that mating is extremely random and based on dominance hierarchies. I wonder what the ratio is of same-sex relationships to opposite sex relationships?

    1. Well Mickell, I can point you to a lecture by Robert Sapolsky that talks about the types of behavior in evolution. It can clear allot of the questions. Just go to youtube and search for "Behavior Evolution Robert" and watch both lectures. They are very informative .

  3. How interesting that sea gulls are monogamous; I never knew that! It's seems as though this is because such high parental investment is needed by both parties in order to ensure that the offspring survive. If it was easier for just one parent to raise the offspring then maybe monogamy would not be so popular (or necessary).

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  5. Hi we live in Great Yarmouth UK and every day for 16 months we wake and our seagull is waiting for us on the shed roof outside our block of flats , at first everyone said he wasn't the same gull but we knew he was as the time goes on, He waits till we throw him food then within seconds she arrives, he chases any other birds away, so I think he considers us to be his area, I find it so nice that he stays with his mate and in the summer they brought baby who annoyed all the neighbours with his love our seagull family and will continues to feed him till they no longer need us x

  6. So sad, picked up a dead seagull from the road today, must have been knocked by a car. It's May and they're just at the point of laying and incubating eggs, I hate to think of that now single parent seagull coping alone but I suppose nature has it's way of sorting things out. We recently moved to Margate UK and have also become very attached to our own resident seagull and her/his offspring. Any idea how you can tell what sex they are? Such beautiful birds,

  7. Not all seagulls are monogamy, at least not in Vancouver, BC.

    I have a polygamy family on a roof out of my window, one male mating two females, busy everyday with chasing away jealous males that want to share his wives.

    Going lesbian seems not the only way to tackle the uneven sex ratio. Polygamy may have some evolution advantages: more chicks are born each year.