These birds are about 7-8 inches in size.  They are mostly brown but have tiny, square, white patches at the corners of their tails.
    Poor-wills lay two eggs on the ground twice a year.  Adult birds who are caring for the eggs or newly hatched chicks can begin a “sleep state” called torpor but they seem to fight doing it.  This could be because torpor will slow down the growth of the chicks and lessen their chances to live.
    Sources disagree if the Poor-will can be called a true hibernator.  Some say they are not because they even go into this “sleep like” torpor when they are waiting for prey.  Hopi Indians were known to call these birds “the sleeping one” because of this.  Other sources show that the birds do enter a daily torpor.  The body temperature of the bird drops more than 35 degrees lower than normal.  This fits in with torpor.
    In 1949, a man named Edmund C. Jaeger is said to have been in a California desert when he found a Poor-will in between some rocks.  The bird was motionless when Jaeger picked him up [although he did open one eye].  Jaeger came back a year later and found the bird motionless again.  Jaeger found that the bird’s temperature was 65.9 degrees on an 85 degree day when its normal temperature is 105.  No amount of handling or yelling at the bird would wake him up.  This fits in with hibernation, too.
    In 1962, Earl Lathrop was hiking with a man named Professor Milliken.  It was reported that they found a bird “sleeping” in the bare sand under a small bush.  The men picked the bird up and found it to be cold and it didn’t fly away or move at all.
    From our research, we think these birds go into ‘sleep-like’ torpors for short periods of time [24-48 hours].  If the weather is extreme—hot or cold—they do it.  If their food source of flying insects isn’t around, they will go into torpor.  Food [even if it is INSECTS] is fuel to the body.  When the Poor-will goes into its temporary torpor—or sleep state—its heart slows and temperature drops.  This means that the bird won’t need as much food to live.  The food already in its body will last longer because it isn’t using much energy in sleep.  This is a way that creatures adapt to where they live, weather conditions, and droughts around them.

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