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Crotalus horridus - Timber rattlesnake
Meaning
Horridus stands for rough, shaggy, bristly; shivering with cold, wild, savage; unpolished, uncouth; frightful, horrible.
Horridus, is the Latin word for "standing on end”.
English name
Timber rattlesnake
Distribution
The distribution of Crotalus horridus starts in southern Ontario, Canada downwards to northern Florida and from the Atlantic coast, where it inhabits a few islands, land inwards as far as Nebraska, Kansas, Oklahoma and Texas.
Habitat
This snake prefers moist forests in the lowlands and hilly woodlands or thickets near permanent water sources and/or swamps with rocky outcroppings or logs and branches that provide shelter.
Description
The average adult size of this snake ranges between 76-152cm with a record of 189.2cm (Klauber 1956).
The ground color varies between gray-, yellow-, -brown or pink to gray. Some specimens, usually from the higher altitudes, are melanistic and mostly black but other "morphs" have also been found in the wild like xanthic or albino.
A reddish brown stripe normally runs down the center of the back which is crossed by a series of large, black, "V-shaped, chevrons" or crossbands. These bands are from 2 to 4 scales wide with a space of about 4 to 6 scales between them and have a light border. They have a large robusk head, which is usually lighter then the rest of the body, with a dark diagonal line through the eye or just behind the eye. Youngsters are patterned the same as the adults but are gray colored until their first shed.
Diet
Timber rattlesnakes prey upon small mammals. Mice, chipmunks, rabbits, voles, shrews, and squirrels is the majority of its diet. Birds and bird's eggs (primarily ground nesters) together with other snakes, lizards, and frogs are eaten occasionally.
Venom
The venom of a Timber rattlesnake is as diverese as its range resulting in a desciption of four different venom patterns in this species (Glenn et al. 1994):
Type A constisting of mainly neurotoxins and found in the snakes living in the southern parts of its range like Oklahoma and Louisiana.
Type B has a venom constisting largely of hermorrhagic and proteolytic activity and is found in the northern parts of its range like northern Louisiana.
Type A+B has both of the above and as you would expect intergrates with the north and south population.
Type C is considert to be a weakest venom with none of the above components and is found mostly in the southeastern range, especially Florida.
Bites in humans often come with massive swelling of the bitten limb, severe pain, ecchymoses, paresthesias, muscle fasciculations, blood clotting problems, nausea, diarrhea and victims may go into shock, but also difficulty speaking or swallowing and myonecrosis (necrotic damage, especially muscle tissue).
Extra
Although, at the moment, there is no subspecies officially recognized, as concluded by Pisani et al. (1972) after the study of the geographic variation, we expect in the future this will change back to what it was, as described by Gloyd (1936a) and Klauber (1936b:196), and both C. h. horridus and C. h. atricaudatus will be reinstated.
Timber rattlesnakes are declining in much of their natural range, eventhough they have in many states a protected status. Habitat destruction and the large number of roadkills is have a big impact, but also the rattlesnake roundups and the general senseless killings pay there toll.
Even more if you take in account that C. horridus does not mature until the age of 9 or 10 years and may only breed every 2 to 4 years that is a massive impact on the population. It is also said that the relocation of timber rattles does not work as relocated adults wander aimlessly, do not feed, and fail to recognize den sites and freeze in the winter.
This is considered to be the most arboreal rattlesnake, especially the subadults, with heights up to 14.5m have been recorded.
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