Fish are low-grade vertebrate warm animals that live in the water all their lives, and their various activities in the water, such as feeding, reproduction, breathing, flocking, evading threats and attacks, are all fish behaviors. Some scholars also attribute fish's change of body color during reproduction and the signal of courtship to their partners as also attributed to fish behavior.
With the exception of some burrowing fish and deep-sea fish, the average fish have more developed eyes with well-structured eyes. Most fish lack eyelids, but some sharks have a transparent transient membrane that covers the eyeball. Mullets and some herring have eyelids that can cover the pupil. Fish don't have tear glands, so fish are one of those creatures that don't shed tears.
Red mullet
The retina of fish is made up of photoreceptor pigment cells such as rods and cones. Usually our human cone cells can feel the light brightness of 0.03 ~ 0.1lx or more, while fish can feel the light of less than 0.03lx, the light sensitivity is stronger than us. The low illumination of the water and the frequent change of light promote the evolution of the fish eye, and such a strong light sensitivity is the result of the fish adapting to the water environment.
The behavior of animals is greatly affected by external environmental factors, and light, as an important ecological factor in nature, has a very obvious impact on fish behavior. For changes in light, fish can regulate themselves to make appropriate behavioral responses.
< h1 class="pgc-h-center-line" > the effect of light illumination on the phototropism behavior of fish</h1>
The phototropism of animals is related to their vision, so the phototropism performance is different in different species and at different stages of development of individuals of the same species. Spotted totoaba prefers to feed under blue light, and the orange and red light of medium intensity show positive tendency, while the Mexican limelia shows significant negative light. Most aquatic animals living in the middle and upper layers of the water show a positive phototropism response, while the lower benthic aquatic animals have a negative phototropism response to light stimulation due to adaptation to the underwater environment of insufficient light.
Light is visually related to aquatic animals, and different species of aquatic animals have different visual pigment cells. In the light experiment of 4 colors, the concentration of plasma cortisol was highest under white light, and the stress behavior was also the most severe. Different light colors and intensities promote or inhibit feeding in aquatic animals. In addition, the swarm behavior and activity behavior of aquatic animals are closely related to light, but this is not simple, most fish have no group activity ability when light intensity is low, while cochineal fish gather together in the dark state.
Schools of underwater fish in the sun
< h1 class="pgc-h-center-line" > the effect of lighting on fish swarm behavior</h1>
The swarm behavior of fish is closely related to light, and the swarm behavior of fish varies with different light intensity, and most fish do not have group activity ability when the light intensity is very low. Some findings suggest that darkness is responsible for the disappearance of swarm activity, but cochineal and perch congregate in the dark, leadfish are clustered at night, and herring in clusters and individuals are rarely or completely inactive at night. This suggests that the behavior of cluster activity may be suspended in a dark state, but may come together to maintain social contact.
< h1 class="pgc-h-center-line" > effect of lighting on fish feeding behavior</h1>
In general, zooplankton and benthic invertebrates are continuous all-day predation, while larger predator predation activity is most intense at dusk and dawn. Periods of low light are always a mixture of activities ' from the weakening of the flock activity of animals to the agglomeration and finally to the individual activity alone or stationary. Large predators clearly took advantage of this chaotic period to prey.
The feeding activity of aquatic animals is affected not only by light intensity, but also by food density and predator activity. When predators and prey occur at the same time and in the same place, many animals often abandon feeding activities to avoid the risk of feeding. Increase their chances of survival by changing the timing of feeding activities and other activity times. Better visual feeding opportunities may be provided during the day, but may be more dangerous when predators who feed visually are present. Under laboratory conditions, young flounders feed day and night, and their activity is intensified when food is present, while their feeding activity is delayed when predator cod appears; however, in nature, their feeding activity occurs mostly during the day and rarely or without feeding at night. This may be due to the presence of predators who suppress their feeding activity. Changes in habitat and other conditions in the environment during the normal feeding activities of animals can affect the ability to predate and evade predation to change the balance between predation and predation.
Sharks hunt schools of fish during the day
< h1 class="pgc-h-center-line" > effects of light on the circadian rhythm and migration behavior of fish</h1>
Each animal has its own unique diurnal laws of activity. When an animal is active depends on a range of factors such as light, water temperature, etc. Many freshwater and marine animals seem to have an optimal light intensity for activity. Zooplankton swimming activity is exacerbated at night, and this phenomenon is also present in adults and juveniles of some animals. Goldfish maintain a weak circadian rhythm under continuous light for several days. Many aquatic animals have the phenomenon of vertical movement day and night, most zooplankton avoid strong light during the day when the light is strong, inhabit the deeper water layer, rise to the surface at night, and alternate with day and night, once a day and night, such as herring and white salmon.
< h1 class= "pgc-h-center-line" > the position of the aquarium and its luminaire configuration</h1>
The growth and development of ornamental fish and bright colors are inseparable from light, especially tropical fish are native to natural light open water bodies, and have adapted to light water life. However, because of its different varieties and development stages, the demand for light intensity is also different, some ornamental fish that need strong light will have poor appetite, dull behavior, and even dull body color when the light is weakened, and some ornamental fish will have a dull body color and lose their luster under long-term strong light.
Secondly, proper light can purify the water quality, if the light is weak and dark, the harmful bacteria in the water multiply quickly, which is easy to cause fish diseases. When the light is too strong, the algae multiply excessively, making the water quality worse. Therefore, whether it is in a fish pond, cement pond or a fish tank at home, it is necessary to pay attention to the light intensity of the feeding environment.
Aquarium placed in front of the window
The best location for aquarium placement is within the range where the morning and evening sunlight can be obliquely illuminated, and the location where the sun can be exposed throughout the day, and proper shade is required, and flowers or potted plants can be used for shade. In the indoor sunlight can not shine in the location need to install lights to fill the light. Fluorescent lamps are soft and have a good viewing effect, but have a poor effect on body color. Incandescent lamps can raise the water temperature, the ornamental effect is slightly worse, and it has a good impact on the color of tropical fish. When installing fish tank lights, pay attention to the quality of the lamps to ensure safety.
References for the installation and use of lamps and lanterns are as follows:
Tables are for reference only
< h1 class="pgc-h-center-line" > summarized at the end of the article</h1>
Understanding the influence of light on fish behavior can better understand fish habits and make it easier to understand the production of certain behaviors of fish. Aquarium light is suitable, ornamental fish can show the most beautiful side to us, light not only affects the ornamentality of the fish tank, but also affects the normal activities of ornamental fish, such as feeding, clustering, etc. What other interesting fish behaviors do you know, and what causes them? Welcome to leave a message below.