Pond Boss Forums FISH & FISHING Fly Fishing & Other Fish Species Israeli Carp

Are Koi just big goldfish? Wife looked up the word Koi and it just means carp. I guess it sounds more exotic to have Koi fish than carp fish.

Somebody set me straight. There surely is a difference.

I believe this is correct. They are just more colorful.

Here is a little background for this topic. Cyprinus carpio is the scientific name - common name is common carp aka German carp. Koi are considered domesticated varieties of common carp, but koi still are the same species - Cyprinus carpio. Mirror carp is considered a subspecies and the technical name is Cyprinus carpio var. specularis but they still belong to the same species as common carp (see below). Mirror carp would be similar to Florida bass being a subspecies of northern largemouth bass; very similar but slightly different. As another example for this discussion it is similar to cattle; Angus, Herford, Holstein, Jersey, Texas long horn, Brahma, etc - all same scientific specie of cow.

Common carp, koi, mirror, and leather carp are biologically quite similar in terms of the same basic physical structure, placement, appearance of fins, mouth barbels, and other various body structure characteristics which play roles in separating species using visual features. Color rarely has importance in separating species. Some websites consider German (‘common’) carp, mirror carp and leather carp the same. One website states this about these carps: “”Variants also include the Mirror Carp which unlike the Common Carp has large irregular and patchy scaling along both sides of it's body making many fish unique and possible to identify by sight. The linear Mirror is scale less except for a row of large scales that run along its lateral line, the Leather Carp is completely scale less, and the fully scaled has a regular pattern of large scales covering the whole body. The difference between Mirror and Common Carp is both genetic and visual - biologically they are similar. As far as I can determine, Israeli carp are a vernacular form of mirror or leather carp. However, these all carps basically feed the same, behave the same, and reproduce the same. As you will see below, they also have the ability to grow to similar top end sizes. Koi are not considered to be a subspecies of common carp – Cyprinus carpio. One advantage in pond management of the Koi is at least some, but not all, of the offspring have bright body colors which makes them easy for predators to see and capture the fish when small.

As a side note and comparison, these three carps are all the same species and technically possess more of the same body structures compared to the basses of largemouth, smallmouth, spotted, redeye, Suwannee, and Guadalupe - who are all scientifically considered different species of the genus Micropterus.

From the web: http://en.bdfish.org/2010/01/mirror-carp-cyprinus-carpio-var-specularis/
From Wikipedia: ""..The difference between mirror and common carp is both genetic and visual - biologically they are similar. The mirror carp was the first mutation of common carp, owing to two alternative genes, the S allele and the N allele. The genetic term for a mirror carp is "ssnn" (all minor). Common carp have an even, regular scale pattern, whereas mirrors have irregular and patchy scaling, making many fish unique and possible to identify individual fish by sight, leading to most carp in the UK over 40 lb being nicknamed. Contrary to popular belief, Leather carp are not Mirror carp without scales; there is a distinct genetic difference. Leather carp are permitted a few scales; however, the dorsal row of scales is either absent or incomplete. Leathers also have reduced numbers of red blood cells, slowing growth rates...""

Feeding Habits of All Three Carps: “”Being predominantly bottom feeders Carp root around in the mud, silt and weeds especially in warmer shallows looking for the next meal. Bloodworm beds are a favorite location for carp, being one of the carp's staple food items along with snails, crayfish, insect larva and almost any other aquatic insect, creature or invertebrate. Carp also eat small amounts of weed and plant life but have become accustomed to anglers baits such as boilies, sweetcorn and maggots etc.”” Note that algae and plant materials are a small part of the carp diet. Any reduction of algae or plant growth from carp is due primarily to their bottom rooting activity that disrupts growth patterns of plants and the resultant suspended sediments reduce water visibility which reduces ability of plants to grow as deep. Accumulation of settled sediments on plants also probably tends to help reduce plant growth.

Thanks Bill!

ps: one last question:
so why exactly do we fear the sterile carp so much more
(and require a permit) than the koi/carp that can reproduce?

By any chance do you have to PURCHASE that permit? .....

stories of grass carp escapees destroying vegetation that was deemed beneficial in public waterways.

No permit needed in Indiana.