The common carp is native to Asia, and has been introduced to every part of the world with the exception of the Middle East and the poles. They are the third most frequently introduced species worldwide, and their history as a farmed fish dates back to Roman times. Carp are used as food in many areas, but are now also regarded as a pest in some regions due to their ability to out-compete native fish stocks. The original common carp was found in the inland delta of the Danube River about 2000 years ago, and was torpedo-shaped and golden-yellow in colour. It had two pairs of barbels and a mesh-like scale pattern. Although this fish was initially kept as an exploited captive, it was later maintained in large, specially built ponds by the Romans in south-central Europe (verified by the discovery of common carp remains in excavated settlements in the Danube delta area). As aquaculture became a profitable branch of agriculture, efforts were made to farm the animals, and the culture systems soon included spawning and growing ponds. The common carp's native range also extends to the Black Sea, Caspian Sea and Aral Sea.
Both European and Asian subspecies have been domesticated. In Europe, domestication of carp as food fish was spread by monks between the 13th and 16th centuries. The wild forms of carp had reached the delta of the Rhine in the 12th century already, probably also with some human help. Variants that have arisen with domestication include the mirror carp, with large, mirror-like scales (linear mirror – scaleless except for a row of large scales that run along the lateral line; originating in Germany), the leather carp (virtually unscaled except near dorsal fin), and the fully scaled carp. Koi carp is a domesticated ornamental variety that originated in the Niigata region of Japan in the 1820s.They also invaded the Great Lakes in 1896 when the area near Newmarket, Ontario, flooded and allowed them to escape into the Holland River.
**Cache at your own risk**
Geocaching, hiking, backpacking and other outdoor activities involve risk to both persons and property. There are many variables including, but not limited to, weather, fitness level, terrain features and outdoor experience, that must be considered prior to seeking a Cache. Be prepared for your journey and be sure to check the current weather and conditions before heading outdoors. Always exercise common sense and caution.
**Remember to be good ambassadors to nature. We as geocachers have a responsibility to leave it as we found it, so others may enjoy nature's glory. Always replace the cache the way you found it, so others may enjoy the find.
For more on geocaching in Iowa, visit the Iowa Geocachers Organization home page 
