Do you know what a free-flowing river is? The connectivity of these rivers is largely unaffected by human-made changes, allowing natural materials to move along unobstructed and animals to swim upstream or downstream unimpeded. Get to know free-flowing rivers: 🌊 Only a third of the world’s longest rivers remain free flowing. 🌊 Connected rivers help reduce risks from floods and droughts. 🌊 These rivers provide important freshwater habitats for vulnerable species. 🌊 Tens of millions of people

22 reactions | A beautiful explanation of the anatomy & process of how cetaceans (in this case dolphins), including the orca uses echolocation. Be sure to check out our earlier clips for examples of just how incredible hearing the orcas underwater can be -> https://goo.gl/6Inp4j | Arctic Freediving - Freedive With Orca | Facebook

🔈 Sound on! Pacific white-sided dolphins are one of the most abudant dolphin species in the North Pacific. Pods typically consist of 10 to 100 dolphins, but they have been seen gathering in the thousands! Dolphins use whistle vocalizations to communicate amongst themselves, and echolocation clicks to "see" their surroundings. Video captured by Monterey Bay Whale Watch | Ocean Conservation Research - OCR