An online resource based on the award-winning nature guide

American Toad Parotoid Glands

7-5-17 parotoid gland - A.toad 055

One of the adaptations that allowed the first amphibians to spend time on land was their skin, as it helped prevent them from drying out. It also served as an effective defense mechanism.

The skin of the American Toad contains multiple glands, both mucous and granular. Mucous glands are scattered all over a toad’s body and secrete a transparent mucus secretion that acts as a lubricant in water and also helps keep their skin moist on land. Granular glands contain a toxin that deters many predators, and is a toad’s main way of defending itself. (In addition, the toxin also protects a toad’s skin from microorganisms as well as helps repair wounds.)

Sometimes clusters of granular glands form a pad, or “macrogland.” American Toads have two such pads, or s parotoid glands, which are located behind their eyes. When threatened, a toad adopts a defensive stance, inflating its body and standing with its hindquarters raised and its head lowered, a position which makes its parotoid glands the first thing that an attacking predator encounters. The secretion from these glands generally induces very serious inflammations of a predator’s eyes or digestive tract, as well as vomiting. Some predators are immune to this toxin, while others, like the American Crow, have figured out a way to prey on toads without consuming any poison — it punctures the toad’s skin with its beak and then pecks out the toad’s liver without ingesting any toxin.

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3 responses

  1. Peter Meyer

    My favorite morning read. Thank you!

    July 5, 2017 at 8:23 am

  2. Alice Pratt

    You know I love toads! Interesting info. Do crows kill a toad and only eat the liver? Hope “my big toad” stays safe! Crows have taken up residence in the woods, here…all their different ‘caws’….recently loud warning caws….sure enough a fox went through the backyard.

    July 5, 2017 at 8:49 am

  3. Inge Ackermann

    I never did like the crow very much! Sincerely, with thanks for the gift you give us daily, Inge

    – Inge 413.549.4870 bobingeack@icloud.com

    >

    July 5, 2017 at 8:51 pm

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