The Grey Whale, Gray Whale, scientifically known as Eschrichtius robustus, is a baleen whale species characterized by its distinctive gray coloration and migratory habits. These majestic creatures are known for their impressive size and unique feeding strategies, playing a vital role in their respective marine ecosystems.
Description & Characteristics
Eschrichtius robustus is a large whale species, reaching an average length of 12-15 meters (39-49 feet) and a weight of 15-35 tons. Their bodies are typically gray, often with patches of white or light gray, giving them a mottled appearance. Their heads are relatively small compared to their bodies, with a distinctive arched back and a large, fleshy hump on their head. They have a pair of small flippers and a broad, flattened tail. The Grey Whale, Gray Whale is distinguished by its baleen plates, which are made of keratin and hang from the upper jaw. These plates act as filters, allowing the whales to strain out small organisms from the water during feeding.
Habitat and Occurrence
Eschrichtius robustus are found in the North Pacific Ocean, with distinct populations migrating between breeding grounds in warmer waters and feeding grounds in colder waters. They are typically found in coastal waters, estuaries, and bays, particularly in areas where their prey is abundant. During their breeding season, Grey Whales, Gray Whales migrate to warmer waters, often along the coasts of California, Mexico, and Central America. Their feeding grounds are located in the Arctic and sub-Arctic waters of the North Pacific, including the Bering Sea and the Gulf of Alaska. This migration pattern takes them through a variety of marine zones, including the neritic zone, the oceanic zone, and the epipelagic zone.
Taxonomy
The species Eschrichtius robustus belongs to the Class: Mammalia, Order: Cetartiodactyla, and Family: Eschrichtiidae. This classification highlights its place within the animal kingdom as a mammal, specifically within the order that includes whales, hippos, and other even-toed ungulates. Eschrichtius robustus is the only surviving species in the family Eschrichtiidae, making it a unique and significant member of the baleen whale group.
Feeding
Eschrichtius robustus are primarily bottom-feeders, using their baleen plates to filter out small invertebrates from the seafloor. Their diet consists of various crustaceans, including crabs, shrimp, and amphipods. They also consume small fish, particularly in areas where fish populations are dense. Their feeding strategy involves using their powerful tails to stir up the seabed, dislodging prey items and creating a cloud of sediment that they then filter through their baleen plates. The Grey Whale, Gray Whale’s feeding habits are a vital component of their ecosystem, as they help to regulate the populations of various benthic organisms.
Image References