Blue Whale (Balaenoptera musculus)
Adult blue whale (Balaenoptera musculus) from the eastern Pacific Ocean.
- Creator
- NMFS Northeast Fisheries Science Center (NOAA)
- License
- Public domain
Blue Whale (Balaenoptera musculus)
Status: needs expert review. Conservation claims cite the IUCN Red List (assessed 2018) and NOAA Fisheries; a science reviewer should confirm the assessment is current and verify subspecies details before approval. The blue whale (Balaenoptera musculus) is the largest animal known to have lived, a filter-feeding baleen whale found in all major oceans.
At a glance
| Field | Value | Source |
|---|---|---|
| Scientific name | Balaenoptera musculus | WoRMS / authority |
| Guild | cetacean (baleen whale) | — |
| IUCN status | Endangered (assessed 2018), population trend increasing | IUCN Red List |
| US ESA status | Endangered throughout its range; MMPA depleted | NOAA Fisheries |
| International trade | CITES Appendix I | CITES |
| Range | All major ocean basins | IUCN Red List / NOAA Fisheries |
Identification
A very large, slender baleen whale that NOAA Fisheries reports can reach roughly 110 feet (about 33 m) in length, with a long mottled blue-grey body, a small dorsal fin set far back, and a broad flat head. The blow is tall and columnar. Several subspecies are recognised, including the Antarctic blue whale and the smaller pygmy blue whale; subspecies identification should be confirmed in review.
Ecology and behavior
Blue whales feed primarily on krill, taking large quantities through lunge-feeding, and NOAA Fisheries notes occasional fish and copepods in the diet. They undertake seasonal movements between feeding and breeding areas. NOAA Fisheries estimates a lifespan of around 80 to 90 years. Behavioral specifics should be cited to published research and confirmed in review.
Conservation status and threats
Commercial whaling in the 19th and 20th centuries reduced blue whales to a small fraction of their former abundance. The IUCN Red List assesses the species as Endangered (assessed 2018) with an increasing population trend — recovery is underway but the species remains far below historical numbers, and the IUCN notes it is among the cetaceans recovering from highly depleted states. It is listed on CITES Appendix I and, in US waters, as Endangered under the Endangered Species Act and depleted under the Marine Mammal Protection Act (NOAA Fisheries). NOAA Fisheries identifies the leading threats as vessel strikes, entanglement in fishing gear, ocean noise, habitat degradation, pollution, and climate change. Report figures as the cited authorities state them; a reviewer should confirm subspecies-level detail.
How to observe responsibly
Whale watching is widespread and often regulated. NOAA Fisheries advises viewers to maintain a minimum distance of at least 100 yards (about 91 m) from whales and limit observation to 30 minutes or less; follow the reviewed observation guide and your region's marine-mammal viewing rules, which may set stricter distances. If an animal changes its behavior because of your presence, you are too close — withdraw. This page keeps to regional granularity (ETHICS.md) and does not publish precise locations.
How you can help
- Log sightings to a recognized citizen-science platform (see the iNaturalist dataset card).
- Support vessel-strike-reduction and quieter-shipping initiatives through credible organizations such as Whale and Dolphin Conservation.
- Report dead, injured, or entangled whales to your regional marine-mammal stranding network.
Sources (3)
Every claim in this artifact traces to one of the citations below. Anything that could not be sourced was left out.
Related in the commons
Azores, Portugal
The Azores are a Portuguese archipelago in the central North Atlantic, sitting atop the Mid Atlantic Ridge. The volcanic islands rise from a seafloor studded with seamounts, and the deep water close to shore makes the ar
Image: NASA / Public domain
Common Bottlenose Dolphin (Tursiops truncatus)
A robust grey dolphin with a short, distinct beak and a curved (falcate) dorsal fin. NOAA Fisheries reports lengths of about 6 to 13 feet (roughly 2 to 4 m) and weights of about 300 to 1,400 pounds, with coastal and offs
Image: Dr. Louis M. Herman. / Public domain
Humpback Whale (Megaptera novaeangliae)
A large baleen whale with very long pectoral fins (up to roughly a third of body length), a knobbly head (tubercles), and a small dorsal fin on a humped back. Often identified individually by the unique pattern on the un
Image: NOAA Gray's Reef NMS / Public domain
North Atlantic Right Whale (Eubalaena glacialis)
A stocky black baleen whale with no dorsal fin, a broad back, and a strongly arched mouthline. The head bears rough patches of thickened skin (callosities) whose pattern is unique to each individual — the basis for photo