Carp feeding activity and oxygen levels in summer
From a metabolic point of view, carp have an essential need for oxygen. If the water is too warm this dissolved oxygen level becomes very low, too low, it then virtually stops feeding. During the hottest hours of the day, schools of carp form around holding areas (shallows, patches of water lilies or pondweeds), or "in between waters" at the thermocline
It is noted at this time that carp tend to become active at night, they particularly appreciate the proximity of living aquatic grass beds that release oxygen from their photosynthesis.
It should be noted that in general carp are guided by three major tropisms, thermotropism by which they seek temperate waters, branchiotropism by which they seek well oxygenated waters, and finally trophotropism by which they seek areas rich in food.
In the midst of a heat wave when oxygen is scarce, this combination is mainly found in well-vegetated, moderately deep areas with higher oxygen levels. In rivers in these hot conditions, fish will sometimes feed near pavements and other waterfalls, which will provide some oxygen. Summer showers and thunderstorms also get them active and if the low pressure lasts for several days, it will be all the better, no matter where you fish! So, surface manifestations (porpoises, jumps) are often observed or heard at night.
But if the waters are too rough, they can be very active.
But if the waters are properly oxygenated, carp fishing can be done in a fairly conventional way directly on the usual feeding areas, for example:
- in dammed lakes: stump fields, marked breaks, old river beds or submerged hedges, stone screes...
- in gravel pits and ponds: clogged areas, fallen trees, reed bed edges, gravel trays, silt pockets...