STRIPED DOLPHIN (Stenella coeruleoalba Meyen, 1833)

Order: Cetacea

Suborder: Odontoceti

Family: Delphinidae

Striped dolphin is a little, slim-bodied Delphinidae, with a pronounced rostrum. It has a slate grey coloration on the back and white on the belly, and a light “brush-stroke” on the flank that goes up to the dorsal fin. Another distinguishing feature is a dark stripe that runs lengthwise from the eye to its rear flank. This dolphin can be found in any tropical or temperate oceanic waters throughout the world. It is a typically pelagic species.

The striped dolphin feeds on fish and Cephalopods.

It is a very sociable species forming medium and large groups (up to hundreds of individuals).

It gives birth to one calf at a time after around 12 months of gestation. Lactation is prolonged up to 2 years.

Once considered rare in the Mediterranean Sea, today striped dolphin is the most common dolphin in pelagic waters. Its expansion, which took place in '900, coincided with the decline of the common dolphin.

These animals are active and curious; they often approach the boats to bow ride.

Birth length: around 0,9 m Birth weight: around 10 kg Maximum length: 2.6 m Maximum weight: 150 kg

BOTTLENOSE DOLPHIN (Tursiops truncatus Montagu, 1821)

Order: Cetacea

Suborder: Odontoceti

Family: Delphinidae

Bottlenose dolphin is a stocky Delphinidae with a pronounced stubby rostrum, pearl grey skin colour, darker on the back fading to white on its belly. The morphology and the colour patterns of this speciers may change according to the geographical area of distribution. Males are slightly larger than females.

This animal lives in every tropical or temperate ocean throughout the world.

The bottlenose dolphin feeds on fish and Cephalopods.

It has a very social nature and it forms small and medium-size groups (6 - 12 individuals).

It gives birth to one calf at a time, after 12 months of gestation. Lactation is prolonged up to 3 years.

The behaviour of this dolphin towards boats is variable: in some areas it is shy, while in others it is curious and confident and one can see them surfing the bow waves. Exceptionally it happens that solitary individuals spontaneously establish relationships of trust with man.

It is the most common dolphin housed in aquariums around the world. It may breed in captivity with some success.

Birth length: around 1 m Birth weight: around 12 kg Maximum length: 4 m Maximum weight: 350 kg

RISSO'S DOLPHIN (Grampus griseus G. Cuvier, 1812)

Order: Cetacea

Suborder: Odontoceti

Family: Delphinidae

Risso's Dolphin is a stout-bodied Delphinidae with a large rounded head and a modest rostrum barely visible. It has a peculiar skin colour; calf’s skin is grey, while adult dolphins have marble skin colour.

One distinguishing characteristic of Risso's dolphins are the non-pigmented scars lining the front of its back and making the head of older individuals almost white. The dorsal fin is relatively high.

This animal lives in all the oceans of the world, except for the polar and subpolar waters. It is a semi-pelagic species.

Risso's dolphin feeds mainly on Cephalopods secondarily on fish.

It is a sociable species forming medium size groups (15 – 20 individuals).

It gives birth to one calf at a time after around 12 months of gestation. Lactation is prolonged up to 3 years.

Risso's dolphins usually show little interest in boats and only occasionally approach the boats and bow ride.

Birth length: around 1.5 m Birth weight: unknown Maximum length: 4.3 m Maximum weight: 600 kg

PILOT WHALE (Globicephala melas Traill, 1809)

Order: Cetacea

Suborder: Odontoceti

Family: Delphinidae

Pilot whale is a big Delphinidae, with a rounded large head and a modest rostrum barely visible. It has got a typical ebony or dark brown coloured skin, with a whitish anchor-shaped patch on its chest. The dorsal fin is broad, with a rounded tip. Males are much larger than females.

It lives in all the oceans of the world, except for the polar waters. We can identify two species belonging to the same genus: Globicephala melas (Traill, 1808), living in cold and temperate waters (except for northern Pacific Ocean) and Globichefala macroryncus (Gray, 1846), founds in tropical and subtropical waters.

Pilot whale feeds mainly on Cephalopods and secondarily on fish.

It is a sociable species forming medium and large sized groups (up to hundreds of individuals).

It gives birth to one calf at a time after 15 months of gestation. Lactation is prolonged up to three years.

Generally Pilot whales are not afraid of boats and frequently approach them to swim around the hull. Sometimes they are friendly and curious about people in the water, but their big size and their unpredictable nature make the contact with them unwise.

Birth weight: around 1.7 m Birth weight: around 90 kg Maximum lengthof the male: 7.5 m Maximum weight of the female: 5.5 m Maximum weight of the male: 2 t Maximum weight of the female 1 t

CUVIER'S BEAKED WHALE (Ziphius cavirostris G. Cuvier, 1823)

Order: Cetacea

Suborder: Odontoceti

Family: Ziphiidae

Cuvier's Beaked Whale is an Odontocete Cetacean, belonging to the Ziphiidae family. It has a stocky build with small head and a short rostrum. It is grey-brown on the back, sometimes with dark bluish tones, fading to white on the head in adult animals. The dorsal fin is small, located well behind the mid-section.

This animal lives in all the oceans of the world except the polar waters, but its abundance is poorly known. It is a pelagic species.

Cuvier's Beaked feeds primarily on cephalopods and secondarily on fish.

Its social behaviour is poorly known. Generally it is sighted in couple or in small groups of 5 - 6 individuals.

Like all cetaceans it gives birth to one calf at a time. Little is known about gestation and lactation period.

Sightings of Cuvier's beaked whales are quite rare, probably because of the long lasting diving behaviour; this cetacean can dive to depths of 2000 m and stay submerged for more than 30 minutes. However a greater research effort has brought a considerable increase in reports.

Only occasionally these animals allow the boats to approach them.

Birth length: around 2.5 m Birth weight: unknown Maximum length: 8 m (around 5- 6 on average ) Maximum weight: 6 t (around 3 t on average )

SPERM WHALE (Physeter macrocephalus Linnaeus, 1758)

Order: Cetacea

Suborder: Odontoceti

Family: Physeteridae

Sperm whale is the largest toothed whale. It has a very stocky build with large head that makes up almost 1/3 of the total body length. The entire body is uniform grey-brown. Sometimes there are white spots around the lower jaw and on belly. The dorsal fin has low, triangular shape and is followed by a series of irregular humps, varying in number. Males are much larger than females.

This animal lives in every ocean of the world. It is a typical pelagic species. In the summer season the males move away from the breeding territories and reach polar waters. The migratory behavior of the Sperm whale in the Mediterranean Sea is poorly known.

Sperm whale eats mainly Cephalopods but sometimes also big and medium-sized fish.

In the ocean the sperm whale has a complex social behavior; males aggregates in large schools and join the females only for mating. In the Mediterranean Sea the sperm whale is sighted usually alone or in little groups of 5-6 individuals. Anyhow it is known that these animals can keep acoustic contacts with each other even over a long distance.

It gives birth to one calf at a time after 15 months of gestation. Lactation lasts at least 2 years, but may extend well beyond weaning (up to 7-10 years).

The sperm whale is quite common in the Mediterranean, especially in the north-western basin, but it is not easy to spot it because it spends most of the time diving. However, you can record the presence of these Cetaceans listening to their unceasing sounds, like a hammer. The Sperm whale can dive to depths of 3000 m, and stay submerged up to 2 hours.

Its behaviour towards man is quite shy.

It is the only Cetacean in the Mediterranean Sea regularly emerging with the fluke before diving.

Birth weight: around 4 m Birth weight: around 700 kg Maximum length of the male: 18.5 m (exceptionally 21 m). Maximum lenght of the female: 12.5 m Maximum weight of the male: 57 t Maximum weight of the female: 24 t

FIN WHALE (Balaenoptera physalus Linnaeus, 1758)

Order: Cetacea

Suborder: Mysticeti

Family: Balaenopteridae

Fin whale is a big Cetacean belonging to the suborder of baleen whales. Despite its gigantic size, its body is very slender; it has wedge-shaped head with a flat top. The colour of its back is gun metal grey while the belly appears lighter. One distinguishing characteristic is the uneven colour of the lower jaw, dark-grey on the left and white on the right. The dorsal fin is relatively small but pronounced and located well behind the mid-section. Females are slightly larger than the males.

This animal lives in every ocean of the world. It is mainly a pelagic species but sometimes it comes close enough to the coastline to be sighted from land. The fin whale eats krill and small fish.

The social behaviour of this species is poorly known. It is frequently sighted alone or in couples and sometimes in small school of 3-4 individuals. Anyhow, the group size may be poorly representative of the social habits of this species, since fin whales are able to keep in touch with each other by means of acoustic contact over long distances.

It gives birth to one calf at a time after about 11-12 months of gestation. Lactation lasts about 6 months.

The Fin whale is the most common Baleen whale in the Mediterranean Sea and it's often sighetd, especially in the north-west portion of the basin.

The behaviour of the fine whale towards man is quite reserved.

Birth length: around 6 m Birth weight: around 2 t Maximum length: 27 m Maximum weight: 80 t

LOGGERHEAD SEA TURTLE (Caretta caretta Linnaeus, 1758)

Ordine: Testudines

Family: Cheloniidae

It is a stout-bodied sea turtle. The carapace has a red-brown colour, smooth in adult specimens and notched in the young ones. It consists of 5 central (or spinal) plates and 5 pairs of lateral (or costal) plates. It is often partially covered by algae and fouling. The plastron (the lower part of the "shell") is yellowish in color, consisting of 6 pairs of plates. The limbs are well developed, especially the front ones, and present a typical "giraffe" colour on the upper side; the same color, slightly darker, characterize the upper part of the head. The head is large, with very robust and hooked beak; the neck is wide and short. Adult males differ from females by the longer and stronger tail.

It is a cosmopolitan species and is found in all the oceans of the world, except for the polar and subpolar waters and the South Pacific.

It has an omnivorous diet, which comprises a large number of marine invertebrates, including jellyfish. With the robust and powerful beak, the green turtle can break the spines of sea urchins and corals. It may catch fish and cephalopods, but it can also feed on algae and marine plants. It is a solitary animal; male and female join each other only to mate in the open sea. A female can join with more males and store the sperm for future litters.

During the breeding season, which in the Mediterranean takes place between June and August, the females return to the beach where they were born. They get out of the water during the night and dig a hole 40-50 cm deep in the sand, using the hind legs. Here they lay up to 150 eggs, each the size of a pingpong ball, with soft-shell, then they go back in the water. The operation takes around 1 to 2 hours and is repeated several times in the same season, at intervals of 10-20 days. Incubation lasts 40-70 days; after hatching, the newborns climb through the sand to reach the surface and immediately run to the sea.

It is believed that light pollution can confuse the hatchlings and divert their path away from the sea, causing the death of entire broods.

Length at birth: about 5 cm Maximum length: 213 cm (usually 80-140) Maximum weight: 545 kg (usually 80-200)

LEATHERBACK SEA TURTLE (Dermochelys coriacea Vandelli, 1761)

Order: Testudines

Family: Cheloniidae

It is the largest of the sea turtles. The carapace is composed of numerous, small dermal plates (osteoderms) arranged in a mosaic and is covered with a layer of smooth and leathery skin, dark brown or black, sprinkled with whitish spots; it is crossed by 7 longitudinal ridges, with the apex lighter in colour (especially in young specimens), while the plastron has 5 fairings. The limbs are particularly well-developed, especially the front ones, and have a color similar to that of the carapace. The head is robust, triangular in shape, and the neck is wide and short. The rostrum has a typical W shape, and the mouth is covered with spines facing inward to facilitate the capture and swallowing of the prey. Adult males are distinguished from females by the concave plastron and longer tail.

It is a cosmopolitan species and is found in all the oceans of the world, except in polar waters. It prefers the pelagic environment, where it manages to find its favorite prey, consisting of macroplancton. It can accomplish extraordinary shifts from one continent to another (up to 20,000 km). In the Mediterranean is present but rare.

It feeds mainly on jellyfish and other organisms that make up the macroplancton, but occasionally it may catch also Cephalopods and fish.

Like other sea turtles, it has a solitary nature; male and female come together only to mate in the open sea.

The breeding season varies from region to region. When the females are about to lay eggs, they go out on the beach at night and dig a hole in the sand, using the hind legs. They lay up to 150 eggs, each the size of a pingpong ball and soft shell. After spawning, the female covers the hole and go back in the water. The operation is repeated up to 9 times in the same season, at intervals of about 10 days. Incubation lasts 50-70 days; after hatching the newborns climb through the sand to reach the surface and immediately run to the sea.

The leatherback turtles are excellent swimmers and plow the oceans hunting jellyfish. The decrease of this and other specialized predator could be one of the causes of the jellyfish increase in all the seas around the world.

The leatherback turtle is on the red list of the IUCN (International Union for the Conservation of Nature) and is considered at risk of extinction

Birth length: 5.5 cm Birth weight: 3.5 g Maximum length: 3 m (usually 1-2 m) Maximum weight: 900 kg (usually 250-700 kg)

GREEN SEA TURTLE (Chelonia mydas Linnaeus, 1758)

Order: Testudines

Family: Cheloniidae

It is a stout-bodied sea turtle. The carapace has an olive-brown colour; it appears smooth in adult specimens and notched in the young ones. It consists of 5 central (or spinal) plates and 4 pairs of lateral (or costal) plates. It is often partially covered by algae and fouling. The plastron (the lower part of the "shell") is yellowish in color, consisting of 6 pairs of plates plus a single anterior one. The limbs are well developed, especially the front ones, and present a typical "giraffe" colour on the upper side; the same color, slightly darker, characterize the upper part of the head. The head is shorter and more rounded than the loggerhead turtle (Caretta caretta) with a robust, non hooked beak, while the neck is long and thin. Adult males are distinguished from females by the longer tail.

It is a cosmopolitan species and is found in all the oceans of the world, except for the polar and subpolar waters. Young individuals swim in pelagic waters, feeding on plankton, while adults prefer the shallow waters along the coast. In the Mediterranean Sea is present but rare. There are reports of some breeding sites in the south-western basin

It has an omnivorous diet; the adults feed mainly on algae and marine plants and therefore prefer the shallows, well lit by the sun, even on coral reefs

Like other sea turtles, it has a solitary nature; male and female come together only to mate in the open sea.

The breeding season varies from region to region. When the females are about to lay eggs, they go out on the beach at night and dig a hole in the sand, 40-50 cm deep, using the hind legs. They lay about 100 eggs, each the size of a pingpong ball and soft shell. After spawning, the female covers the hole and go back in the water. The operation lasts 1 or 2 hours and is repeated many times in the same season, at intervals of about 10-15 days. Incubation lasts 40-70 days; after hatching the newborns climb through the sand to reach the surface and immediately run to the sea.

Green turtles are known for their long migrations (up to 2,000 km) to move from the feeding waters to the breeding sites. It is well known the extraordinary migration accomplished by some Atlantic individuals to reach the small island of Ascension, in the center of the Atlantic Ocean, from the coast of Brazil. These migrations provide exceptional guidance systems.

Length at birth: about 5 cm Maximum length: 150 cm Maximum weight: 395 kg (usually 200