Every year, between July and November, groups of southern right whales (Eubalaena Australis) visit the coast of Uruguay. They can be seen in several areas, such as José Ignacio, Cabo Polonio, and Punta del Este. The maximum size of an adult female is 15 m (49 ft) and can weigh up to 47 tonnes. Maldonado Bay allows the whales to come really close to the coast, so they can easily be observed from the beach. It is an incredible privilege to be able to sit on the beach and just watch at whales playing only tens of meters away.
The southern right whale is a migratory species, exclusively distributed in the Southern Hemisphere. During summer, they can be found at feeding areas in high latitudes. In early winter, the whales migrate to Peninsula Valdes in Argentina where reproduction and birth take place. On their way to the South, they pass by Punta del Este and often take a break here. Although advised against, some people also try go get real close and personal with the animals. Although I've never heard of agressive behavior, one can only imagine what happens if 15 tonnes decide to play with you or just doesn't notice you when rolling over...
In 1789, a whaling factory was established in Punta del Este by the Real Compañía Marítima. Whales were caught in Maldonado Bay, the same place were these photos were taken. Whaling was done extensively (not only by Uruguay by the way) causing the population of southern right whales to drop to the point of extinction. In fact, it was considered commercially extinct in 1840. Luckily, due to increased awareness and protection of the species, number have been growing significantly since the 1960's. Around 2005, the total population was estimated at 10.000, but apparently population growth is fluctuating.
Bonus fun fact: the testicles of right whales are likely to be the largest of any animal, each weighing around 500 kg (1,100 lb).