Why is it Important to Know When Carp Spawn?
It is important to know when do carp spawn because by the time you see eggs and carp thrashing about in the weeds, you have likely already missed half of the season’s best fishing. If you want to capitalize on the great fishing that occurs pre-spawn as well as during the spawn you need to be able to predict when carp spawn.
Three Factors that Trigger Carp Spawn
If you try to find out when common carp spawn you will quickly discover conflicting information. Some people say March to June, some people say year round, some people say May to early July, and some Say August to October.
The problem is that they can all be right depending on the conditions. Common Carp spawning is triggered by three factors: water temperature, day light, and water level. The conditions, not the days of the calendar dictate the spawn. When all three conditions align in the spring the carp will spawn.
If after three months all three conditions are again favorable, the carp will spawn again in the fall. If all three conditions stay right all year round (as in some tropical areas) then the carp will spawn all year round.
In the southern United States there are typically distinct spring and fall spawns. In states that are on approximately the same latitude as the Mason-Dixon line (Virginia, Maryland, Kentucky, Ohio and so on) the fall spawn may be present but involves only a smaller portion of the fish. In more northern states the fall spawn may not occur at all or just sporadically.
Common carp can also experience protracted spawning or even fractional spawning. This means that carp do not all breed at exactly the same time. The spawning process can be stretched out over a period of a month or more and sometimes spawning can be broken up with one group of carp breeding early and the other breeding a few weeks or even a month later. No one knows exactly why some spawns are more protracted or fractional than others, but the time (and length of time) that all the ideal spawning conditions coincide may explain this.
Optimal Water Temperature for Spawning
Optimal or peak spawning temperatures are between 18 C (64.4 F) and 23 C (73.4 F) [though some research suggests that the optimal range is actually 19 C (66.2F) to 23 C (73.4 F]. The optimal temperature range may differ slightly in different climates. However, spawning can occur in a range of 15 C (59 F ) to 25 C (77 F ). Spawning decreases dramatically at temperatures above 26 C (78.8)and spawning ceases completely at 28 C (82.4).
In addition to temperature, the day light hours need to be sufficiently long. There is not a lot of research on how much day light is necessary because in North America and Europe you rarely reach your required water temperature without sufficient day light.
Once the water temperature and daylight conditions align, the carp then wait for water levels to rise and sufficiently cover the vegetation that the carp lay their eggs on. Carp lay their eggs on emergent vegetation and they cannot lay their eggs unless there is sufficient water to cover their eggs and sufficient water to allow them to swim into the reed beds.
Consequently, most research papers that studied common carp spawns, noted that the spawns occurred immediately after an increase in water levels during optimal temperature conditions. Sometimes spawning only requires very small increases in water levels, less than 7 cm (2.8 inches) in one documented instance.
If you want to take advantage of the spawn and pre-span periods, wait until water temperatures reach 18 C (64.4 F) and start fishing the margins around emergent weed beds. The spawn will begin after the first rain storm or increase in water levels that cover the emergent vegetation along the shore. If you see only a few fish thrashing around in the weeds by the time water levels decrease, the spawn may continue after a second good storm so don’t give up if the fishing tapers off at first.
About three months after the spring pre-spawn, watch for water temperatures between 18 C (64.4 F) and 23 C (73.4 F) and then wait for increased water levels that cover the shoreline vegetation to signal the fall spawn.