The Sesimbra coast is a migratory ecological corridor located in the heart of the Atlantic Ocean that serves as a natural “highway” for various species of cetaceans.
Are there whales in Sesimbra?
Yes, large whales, such as the fin whale (Balaenoptera physalus), use these waters during their migratory routes between feeding grounds in the North Atlantic (Greenland/Iceland) and warmer waters, such as the Strait of Gibraltar, Madeira, and Cape Verde.
Due to a consistent increase in sightings of these large cetaceans in this area throughout much of the year, Bolhas Tours has identified this location as a migratory corridor: the Sesimbra Whale Corridor. It is here that we have recorded the highest number of whale sightings, notably of the fin whale and Bryde’s whale.
Here and during the month of May, the fin whale was once again the most frequently observed species with four sightings, and the sighting with the largest number of individuals occurred on April 20—a group of four fin whales.
Why are there whales in Sesimbra?
The first record of the presence of these cetaceans dates back to the 13th century (1274) in a document referring to the taxes to be collected by the Crown from fishermen in Sesimbra and Sines for the capture of whales and dolphins.
The continued historical presence of these cetaceans is closely linked to the region’s geological and oceanographic characteristics.
The proximity of the Setúbal submarine canyon, which extends to the northwest, combined with the influence of currents from the Sado River estuary and, further north, the Tagus River, creates areas of high marine productivity.
From a geological perspective, the Setúbal canyon is a deep submarine valley, formed over millions of years through a combination of three processes: ancient fluvial erosion (when sea levels were lower), turbidity currents (rapid descent of sediment flows along the seafloor), and natural tectonic dynamics, so prevalent in the Eurasian Plate, especially in this area where it meets the African Plate.
The morphology of the Arrábida Mountain Range’s limestone massif protects this coast from winds and waves from the north and northwest.
This natural protection benefits large cetaceans by ensuring:
- Better energy conservation—less effort in swimming and resting
- More effective communication and echolocation—due to reduced underwater noise
- Easier food capture—allowing for more efficient hunting.
As a habitat, the Setúbal Canyon plays an essential role in the marine ecosystem, promoting the phenomenon of upwelling (the rise of nutrients from the ocean floor), which, in turn, increases water productivity and creates ideal conditions for the development of a wide diversity of marine life.
This increased food availability, closely linked to the unique geology, transforms the Sesimbra region into a true “hotspot” of biodiversity, attracting cetaceans such as dolphins and whales, which seek out these areas to feed during their migrations or seasonal movements.
How do we participate in conservation?
Daily records of these observations are collected by biologists and subsequently shared with entities such as the ICNF (Institute for Nature Conservation and Forests), the Whale Museum (Madeira Island), under a protocol established with Bolhas Tours (2026), as well as with various university researchers dedicated to the study and conservation of different cetacean species in this area of the North Atlantic, who accompany us on many of our expeditions.
The scientific significance of this ecological corridor underscores the importance of continuing to monitor, study, and protect this unique marine heritage in Portugal and Europe.
The Dolphin and Whale activity offered by Bolhas Tours allows for a constant presence and monitoring of the ocean, particularly in the Sesimbra whale corridor, making marine tourism a truly active tool for increasing scientific knowledge about the Sesimbra coast in support of species conservation.
