Marine mammal, class Mammals, order Cetacea, suborder Delphinidae, species Delphinus delphis
Size: 0.80 at birth, from 1.6 m to 2.40 m
Weight: 150 to 200 kg
Duration of gestation: 11 to 12 months, breastfeeding period at least 10 months, there is one birth every 3.
Food: anchovies, sardines, mackerel, cephalopods, squid
Sexual maturity: females 2 to 7 years for males 3 to 12 years. Lifespan: 35 years
Distribution: cosmopolitan species. It is present in all the seas of both hemispheres with water temperatures ranging from 10 to 28°C, including the Mediterranean and the Black Sea. Usually it avoids the polar regions.
Threats: still hunted today in Japan, Norway, the Mediterranean and the Black Sea for its meat and oil
Protection: minor concern under IUCN status International Union for Conservation of Nature. It should also be noted that overfishing of sardine stocks deprives them of their basic food resources.
How to meet them: since 01/01/2021, in France it is prohibited to intentionally approach protected cetaceans and sirenians within 100 m in protected marine areas and in marine waters under sovereignty and jurisdiction, maximum speed of 5 knots, do not cut them off, limit meetings to 1/4 hour, respect the signs: tail slaps, air bubbles, which mean DISTURBANCE. Do not feed them, no fishing lines, do not attempt to swim with Common Dolphins.
Observation areas in the Mediterranean THE COMMON DOLPHIN The common dolphin is a cosmopolitan species. It can be found in all the seas of both hemispheres with water temperatures ranging from 10 to 28°C, including the Mediterranean and the Black Sea. Usually it avoids the polar regions. It is absent in the Indian Ocean. It is observed exceptionally in the Gulf of Lion.
3 key facts about this unusual cetacean
1 – Like the Bottlenose Dolphin, it is a top predator, it regulates lower trophic levels and makes it possible to account for the state of health of an entire ecosystem. Its importance is major and even if this species is not endangered, the IUCN International Union for Conservation of Nature has classified the COMMON DOLPHIN as “minor concern” but “absent in the western Mediterranean and in sharp decline elsewhere”. Their population in French territorial waters is estimated between 180,000 and 200,000 individuals. On a European scale, there are 500,000 individuals. There are over 700 strandings on beaches annually, this is only the visible part. We are trying to assess the actual mortality at sea. We can estimate the number of dolphins dead at sea at 4,000 individuals, which is very worrying.
2 – Gestation is approximately 10-11 months, the dolphin calf is weaned after 10 to 12 months. The common dolphin community is very supportive; this ranges from caring for newborns and injured companions to the problems of infirm and elderly members. There are even reports of drowning humans being pushed to shore, supported by dolphins. It is common to see common dolphins playing with floating toys, or even animals like turtles. Mating takes place delicately, it seems that real love is manifested between the male and the female. Offshore species are found in herds of hundreds or even thousands of individuals (500 on average). The clicking sounds are emitted by its vent and its echolocation system. Its top speed is around 40 km/h. (source Doris)
3 – The COMMON DOLPHIN reaches a maximum size of 2.50 m for males and 2.30 m for females. At birth it measures 70 to 80 cm. Its weight is between 70 and 110 kg. The beak (or rostrum) is thin and is well demarcated from the melon (head) by a frontal furrow. The dorsal is falcate and measures a third of the body to the right of it. The caudal is brace-shaped with a notch in the hemispherical axis. The coloring of the back varies from dark gray to dark brown to black; it forms a V under the dorsal. The coloring is lighter towards the tail. The belly from the head to the anal region is creamy white then light gray. On the sides two lines intersect to form an X.
Observation and interaction tips 1 – Getting into the water to swim with COMMON DOLPHINS is not recommended. In France it is even forbidden to approach within 100 m. If they choose to come swim from the bow, which is common, or visit you during a swim in the sea, you can take advantage of it while not exceeding 5 knots and maintaining a straight and parallel trajectory without trying to join them. . When meeting them while swimming, never try to touch them, their skin is extremely fragile. 2 – Do not try to feed them, they are great hunters and a good part of their time is devoted to hunting, they can go down to depths of up to 300 m. They feed on fish living in schools such as anchovies, sardines, herring, but also squid and cuttlefish. The hunting technique consists of bringing the fish up by releasing bubbles or by pulling down. It is of course a collective tactic: some feed, others scavenge the food and the last protect the group. 3 – The best way to meet COMMON DOLPHINS is not to look for them but to observe them. The encounter can be opportunistic: your paths cross, but these encounters can also be the subject of a different way of NAVIGATION TO OBSERVE and go to meet all the species that populate our Great Blue.
You can download the Common Dolphin sheet in French and English
If you want to know more about the COMMON DOLPHIN visit the excellent DORIS website . Observing is learning and many associations offer naturalist observation trips to eco-volunteers where you will learn a lot about these MASTERS of the oceans that are the Cetaceans.
@parc.naturel.marin.golfedulion @villedeleucate @navily @leucate.tourisme
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