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The Orcas!

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May 12, 2019

With the specific name Orcinus orca, they belong to the order Cetacea and the Odontoceti family. Although they are called Killer Whales, the truth is that they are neither Whales nor Killer!

It is thought that their name comes from their size and the fact that they are top predators!
They are the largest dolphins in the world (Yes, they are dolphins!) And can reach up to 9 m in length and almost 6 t in weight. They exhibit sexual dimorphism, which means that males are different from females, not only in size but also in appearance. The dorsal fin of the males is very high, reaching up to 2 m, and straight, while that of females is smaller and more falcated (rounded).

It is the cetacean with the largest distribution worldwide, occurring in all oceans, from pole to pole.
They develop matriarchal-based social groups, consisting of two to four generations of individuals. These types of groups are very stable over time, and it is thought that all individuals contribute to the "education" of the offspring.
While females are almost always observed in groups, it is common to find solitary males.

They are very active animals on the surface, reacting in very different ways to the approaching vessels. The population that is observed in the Algarve is the same one that is identified in the Strait of Gibraltar, and it is believed that it was once abundant in our waters.
Figura 1 – Golf of  Cadiz

In addition, it is thought that this population fed on cetaceans and other marine mammals inhabiting the area (such as the monk seal, Monachus monachus) but that, as Mankind depleted these populations in the Gulf of Cadiz, the orcas had to adapt and specialize in other prey. Today, this population feeds almost exclusively on Tuna fish (Thunnus thynnus).

In terms of frequency of observation, we can usually observe this species along our coast once or twice a year, usually in early spring and again at the end of summer, when Tuna passes by our coast in its annual migration to the Mediterranean Sea.

Here are some pictures of these observations!

Figura 2 - Orca (Orcinus orca) 2019

Figura 3 - Orca (Orcinus orca) 2019
Figura 4 - Orca (Orcinus orca) 2018
Figura 5 - Orca (Orcinus orca) 2018