how big is the second marine animal mentioned?
A maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed.
Introduction
 is a marine mammal belonging to the baleen whale suborder Mysticeti. Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed. The blue whale’s long and slender body can be various shades of grayish-blue dorsally and somewhat lighter underneath.

who makes up most of the population of antarctica 5,000 in the summer and much lesser in winter where did it get the name from? It is the romanised version of the Greek compound word "antarktiké" meaning "opposite to the Arctic", "opposite to the north" what kinds of animals can be seen there? Some species of marine animals include penguins, blue whales, orcas, colossal squids and fur seals what sort of weather conditions it has? It is the coldest of Earth's continents.
Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed. It can reach a maximum confirmed length of 29.9 meters and weight of 173 tonnes. Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed.
Blue whale Blue whale Blue whale
Introduction Introduction Introduction
Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed.  Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed. Reaching a maximum confirmed length of 29.9 meters (98 feet) and weight of 173 tonnes (190 tons), it is the largest animal known to have ever existed.
wiki:1554442
Blue whale [SEP] Introduction
m. indica" in the Northern Indian Ocean, and "B. m." unnamed subsp. in the waters off Chile. The blue whale diet consists almost exclusively of euphausiids (krill). The blue whale was once abundant in nearly all the oceans on Earth until the end of the 19th century. It was hunted almost to the point of extinction by whaling until the International Whaling Commission banned all hunting of blue whales in 1967. The International Whaling Commission catch database estimates that 382,595 blue whales were caught between 1868 and 1978. The global blue whale population abundance is estimated to be 10,000–25,000, roughly 3–11% of the population size estimated in 1911.