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Bull Moose Sexually Advertising

10-12-15 moose 20090924-01 080As part of the rut, or breeding season, that they are in the middle of, bull moose seek to advertise their wares as far and as wide as possible. Information regarding the moose’s dominance is conveyed visually to cow moose (as well as other bull moose) by the size of a bull moose’s antlers. Additional information is conveyed olfactorily through the transfer of urinary pheromones via the bull moose’s bell, or dewlap (structure located under the chin of both bull and cow moose).

A moose’s bell increases in size with age (the pictured moose is just a yearling). While there are many theories as to the function of the bell (thermoregulation during the heat of summer, extra insulation for a moose’s chin when bedding down in snow and a secondary indicator of sex and age), it has been confirmed that the bell is an olfactory device that plays a role in communication.

During rut a bull often digs a depression (wallow) in the ground in which he urinates. He then proceeds to stamp and wallow in this depression, thoroughly soaking his antlers, belly and bell with his pheromone-laden urine. Cows are attracted to this pungent scent. Suspended from the bull’s body, the bell is an excellent way of dissipating these pheromones into the air – an innovative means of sexual advertising.

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10 responses

  1. Bill On The Hill...

    Hi Mary… A most excellent profile shot on this young bull moose as the detail looks really good.
    I have no doubt you cropped this in a bit but it still looks like you got close enough for a good shot using your 400 mm?
    Bill @ WGF Studio53

    October 12, 2015 at 8:35 am

    • Hi Bill,
      That photo was taken with my 10-400 lens…and yes, I was very close!

      October 12, 2015 at 11:37 am

  2. Barbara

    What is the smell of this ingenious sign of maleness? I’ve been smelling what I’ve come to think of as fox pheromones in a particular place in the woods. A bit of a skunky smell. I know that we’ve moose in the area.

    October 12, 2015 at 10:57 am

    • Hi Barbara,
      Your skunk smell could well be skunk or possibly fox, though it’s a bit early for fox urine to be heavily scented. I honestly have not experienced the thrill of smelling a moose in rut, but I will try to find the answer for you as to what it smells like. “Pungent” is the word most commonly used…

      October 12, 2015 at 11:39 am

    • Barbara, I asked a naturalist/hunter friend what a bull moose in rut smelled like and he (Alfred Balch) said “like a hot, lathered horse combined with the smell of licorice. Strong but not unpleasant.” He said you could follow the moose’s trail for some distance by smelling the brushy growth he goes over.

      October 13, 2015 at 7:14 am

  3. Downright smelly, I would guess! I wouldn’t be in a big hurry to get close enough to a bull in rut to smell it…their aggressiveness is legendary!

    October 12, 2015 at 4:25 pm

    • Eliza, see my response to Barbara!

      October 13, 2015 at 7:14 am

      • Licorice? who would’ve guessed it? 😉

        October 13, 2015 at 2:31 pm

  4. Not I, Eliza!

    October 13, 2015 at 3:47 pm

  5. Thank you . Really interesting post

    October 14, 2015 at 10:14 am

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