Mirror carp and leather carp are large coarse fish found throughout the world. They are the same species as common carp but are radically different in appearance.
Mirror carp and leather carp are a fascinating species and anglers are incredibly passionate about fishing for these wonderful creatures.
Mirror carp and leather carp (scientific name Cyprinus carpio) are freshwater coarse fish species of the Cyprinidae family. This family is widespread throughout our waterways and includes common carp, roach, bream, gudgeon and barbel.
Mirror carp are subspecies of common carp and biologically they are almost identical. It is widely thought that mirror carp was the first mutation of common carp. Mirror carp are popular amongst anglers as they are thought to grow larger than common carp on average.
The reason for this is that common carp expend a lot of energy growing scales whereas mirror carp can focus on growing their size.
Leather carp are not mirror carp with fewer scales, they are a subspecies of common carp in their own right. They do not have as many red blood cells as common or mirror carp which stunts their growth. This makes large leather carp rare, however the larger specimens are sought after catch by anglers.
There is a small demand for mirror carp and leather carp in garden ponds however their cousins the goldfish and koi carp are far more popular for this purpose.
Common carp are farmed around the world, however farming for mirror and leather carp is rarer. Carp are very popular as they are very fast growing, considered easy to rear and they do not require running water.
The purpose of farming the fish is for as use as food and for use as an angling fish. Carp farms can be found across Asia and Europe, particularly in eastern Europe where carp are a very popular fish for the table. Carp are actually the most popular fish which are farmed across the world.
Carp have been consumed throughout history in their native and introduced countries. Throughout the Middle Ages monks grew carp in their stew ponds for the table, and it is even thought that monks would select carp with fewer scales (to make them easier to prepare to eat) which led to the development of mirror carp.
In the UK carp are thought to have a muddy or grass taste so are not widely consumed. Carp are a very popular eating fish in Eastern Europe where eating them is a festive tradition in some countries. Carp are popular to eat whole as they have Y-shaped bones which makes them fiddly and difficult to fillet.
Distribution and Habitat
Mirror carp and leather carp share a similar distribution to common carp. Common carp are native to both eastern Europe and Asia. Common carp are native to areas as far north as Russia and Ukraine, as far east as Vietnam and China, as far south as Croatia and Azerbaijan and as far east as Hungary and Austria.
Carp are extremely dispersed as a species and have been introduced to over 80 countries! It is quite remarkable that they can be found in American countries including Canada, the USA, Dominican Republic, Mexico, Argentina and Uruguay.
In Africa, they can be found in many countries including Nigeria, South Africa, Egypt and Ghana. They can be found in Asian countries where they are not native, including India, Nepal, Saudi Arabia and the Philippines.
They can be found in European countries where they are not native, including France, Austria, Italy, the UK and Portugal. They can also be found in the Oceanic countries of Australia, New Zealand and Papua New Guinea.
In some areas where carp are not native and were introduced, they are treated as pests. In southern Australia it is illegal to return the fish to the water in the hope that they do not spread.
There are attempts to remove them from some waterways in the USA in the hope to stop them spreading. There are several reasons why they are treated as pests, however it is mainly because they are mobile, fertile, long lived and their feeding can damage the ecosystems. There is also little demand in these countries for carp as an eating fish apart from in isolated areas.
Carp can be found in some slower moving rivers, however they tend to thrive in stillwaters such as ponds, lakes and reservoirs. Carp can tolerate brackish water if necessary in some locations.
Carp are a very hardy species. They can survive in waters with a low oxygen content by breathing at the surface and you can sometimes see or hear them doing this. They can endure very cold and very warm temperatures which ranges between 3 and 34 degrees Celsius.
Carp often move to deeper areas of water in cold weather as the deeper water has a higher water temperature. They will survive in many northern countries where the water has frozen over on the surface.
Mirror carp and leather carp are large fish with deep, heavy bodies. The colouration of mirror carp and leather carp is similar.
They have grey or brown backs. Their flanks are bronze, olive green, dark yellow or brown in colour. They have white or very pale yellow bellies.
The scales on mirror carp are irregular compared to common carp. Mirror carp may be fully covered in scales or only partially covered. The scales which they do have tend to run along the lateral or dorsal lines.
Leather carp do not have any scales apart from possibly some around their dorsal and caudal fins. The scales of mirror carp and leather carp are relatively large and they do not have any scales on their heads.
Carp have long dorsal and caudal fins which are grey in colour. Leather carp may have imperfect dorsal fins which have fewer rays. The anal and pectoral fins are usually a lighter colour, and can be orange and red however this depends on the environment.
Like their cousins barbel, carp have four barbules on the sides of their mouths (a pair on each side). The most noticeable pair of barbules are found immediately to the corner of their mouths and are long and the less noticeable pair are located higher up the mouth and are short.
Carp have thick, rubbery lips and their upper jaw very slightly protrudes. Carp do not have teeth within their mouths, however have pharyngeal teeth which they use to crush their food before swallowing.
Mirror carp are a large coarse fish, however some specimens can grow to very large sizes indeed. Carp are slower growing in the UK so they do not grow the to larger sizes which can be found over the English Channel in the warmer weather in continental Europe.
Mirror carp specimens of over 70lb are regularly caught throughout the warmer countries in Europe, however the record holder was caught near Bordeaux, France in 2010 and weighed in at a whopping 94lb. This monster was caught by Martin Locke (an Englishman from Kent).
Leather carp do not grow as large as mirror carp or common carp so it is much more difficult to find larger specimens.
In the UK, mirror carp weigh on average between 5 to 15lb (approximately 2.25 to 6.8kg). The current British record weighed in at 65lb 14oz.
In the UK, carp grow on average to approximately 18 to 26 inches (45 – 65cm) in length however if you are lucky you could catch one of the larger and older specimens which can grow up to 48 inches (120cm) in length.
The average lifespan of carp is approximately 10 – 50 years, however it is likely that older specimens could be found in prime habitats.
How they Feed
As with common carp, mirror and leather carp are omnivorous and are not particularly fussy. They are greedy and will sift through silt to find their food, for this reason they have been nicknamed “freshwater pigs”.
As with other species within the Cyprinidae family, carp utilise their barbules to detect the micro-organisms which they feed on. They are very thorough and will sift through the mud and silt to detect their food. When they disturb the bottom, a cloud is formed which you can sometimes see from the surface.
This process of disturbing the bottom of the water can disrupt the ecology of the water as this will stifle sunlight from reach plants and can have a knock on to other species in the water. Carp are known to feed on the surface for insects.
Mirror and leather carp will happily feed on aquatic plants and weed, algae, invertebrates, molluscs, snails, other smaller fish and crustaceans. Amongst their favourite food is freshwater mussels which they can eat with the shell by crushing with their pharyngeal teeth.
Mirror and leather Carp reach sexual maturity at the ages of 2 to 3 years of age. Spawning is dependent on the habitat where the carp live. Spawning begins when the temperature of the water reaches between 16 to 22 degrees Celsius, which is generally late spring or early summer in the UK but earlier in warmer areas of Europe.
Mirror carp and leather carp will both spawn a percentage of common carp fish due to their similar genes which remain in the subspecies.
Once spawning begins, carp will move to areas with thick weed in the shallows. There is evidence that carp prefer to spawn after rainfall which raises the water. When spawning, male and female carp swim together.
The females deposit their eggs which males then rush to fertilise. The eggs slowly sink to the weeds which they stick to. The carp eggs are pale orange have a yellow colour. Healthy females can lay up to a staggering 100,000 eggs. Carp can spawn more than once per season.
Unlike other species, the parents do not protect the eggs once deposited. It takes three to eight days for the eggs to hatch, however this depends on the climate and environment.
The juvenile carp will remain attached to the vegetation for 2 to 4 days after hatching until they fully consume the yolk sac which provides them with nutrients. Once the yolk sac has been fully absorbed, the juvenile carp will be approximately 8mm in length.
The juveniles will remain in the weeded and shallow areas for protection from predators and faster currents. As the carp grow older they will move into the deeper water.
The juvenile carp can be targeted by predators in the water such as perch and pike however the larger fish will be too big for predators.
How to Catch
It is uncommon to find mirror carp and leather carp in rivers in the UK and most carp are caught in stillwaters. Most fisheries stock carp and may advertise that they stock mirror carp or leather carp.
A good fishery should stock mirror carp, however the leather carp are probably rarer. Once you have found a decent fishery which stock the variety you are looking for, you could try various locations in the water to find them.
You could look out for reed beds, overhanging trees or any overhanging vegetation from the banking as carp are likely to lurk here.
Carp use these areas of cover so you could try fishing there to tempt them to your bait. Carp can occasionally be seen from the surface to be in the in the sun’s rays, and they may be reluctant to feed on sunny days.
In terms of bait, boilies and pellets are a favourite by many anglers (including us!) and have been for some time. Carp are greedy and will generally be attracted by a large variety of bait, we have spoken with anglers who even prefer meaty or spicy baits.
Some good baits include dog biscuits, bread, worms, peanuts, luncheon meat (you could flavour this for extra smell), maggots, casters, sweetcorn, mussels, brandlings and red worm. It’s worth trying a variety to see what works for you and use your favourite for future sessions.
You can catch carp using a few different methods. You could try float, ledger and feeder are and meet with a lot of success. There are many variables to consider with carp fishing and the ledger and feeder methods are probably more popular if you are looking for larger specimens.
The size and weight of carp can vary so much that it is hard to suggest tackle. If you are looking for average sized carp (or if the fishery has previously advertised the weights and you know that they stock average sized fish), you should use a decent rod with a 2lb test curve fitted with a fixed spool reel.
Groundbait works very well for carp and you can get creative with the different types you could make. Try to include some of your hookbait in the mix to really get the fish interested.
When you bring the catch to land, use a good quality landing net (at around 30 inches or so) and allow the fish some time to recover in the net. For larger fish, use a weight sling (you can find these in good tackle shops and online) and use this to raise the catch. Try to life the fish some distance away from the banking so that the skin, scales and slime are not damaged by anything protruding from the banking.
Lift your catch onto a good carp unhooking mat (you may need someone else to help for bigger fish!). Try to minimise the distance between the banking and mat so you do not have to walk too far.
Carp are generally easy to unhook as the hook will be found in the rubbery lips. Try to keep a disgorger or forceps with your tackle in the unlikely event that the fish is deep hooked.
If you are looking to weigh your catch, try to minimise the distance between the fish and the ground (you can get tripods for this which are very good). If you are going to keep the fish out of the water for some time, keep wetting the fish to make sure it is kept healthy. This is especially important if you see the slime drying which will turn a white colour.
Carp can be damaged by predators (when they are young) and through foul hooking. You could take a treatment along to put onto the wounds if you wish. If you notice the fish has sores then report this to the fishery owner.
If you would like more information on how to fish for mirror carp or leather carp, or would like some further information on angling techniques, check out our fishing tips page for more information!