Science has been documenting a dramatic shift in the migration patterns of Arctic marine mammals. Whales are changing the timing and routes of their migrations. Narwhal have moved further out to sea. Diminishing sea ice and changing ocean currents draw them away from long held patterns.
Marine Mammal Migrations Greatly Effected by Climate Changes
Overfishing in warmer seas
Many animals depend on the fish swimming in Arctic seas. Diminishing sea has enabled fisherman to begin fishing with long lines and nets earlier in the year. They compete directly with animals for the fish in the sea. Halibut have grown significantly smaller in recent years due to the increased catch of this valuable fish.
The Unicorn of the Arctic
The Narwahl is the mythical unicorn of the arctic. They are sensitive creatures that have avoided humans and predators using sea ice and their capacity to dive to 1500 meters or more. As sea ice declines and human activity in the arctic increases, these mysterious animals will be subject to more stress, hunting and predation.
Climate Chaos: Marine Life & Oceans
Life in the Warming Arctic Seas
The oceans of the Arctic are unique. For millennia, sea ice covered vast expanses of these waters for much of the year and thick, multi-year ice built up over time, becoming whiter and reflecting heat from the sun. As the Arctic has seen record temperatures over the last several years, much more of the sea ice melts completely and the thick layer of older, white ice is becomes scarce. In the near future, scientists anticipate a summer when sea ice will be entirely gone from the Arctic Ocean. For the animals that live on or near the ice, these changes in sea ice and the warming of the ocean waters will have a significant impact on all aspects of their lives. Fish populations are changing. Some of this is due to overfishing, made easier by diminishing sea ice in spring and fall. Warmer, more acidic water also changes the food sources for fish and can deeply impact their populations. As the warmer, Atlantic waters move north, they bring species not normally seen in the Arctic. Whale migrations have shifted significantly in recent years. The whales now move at a different time and along a different path than the routes they’ve used for as long as humans have anticipated their whereabouts. Narwhal appear to be suffering from overhunting in parts of Greenland as the sea ice becomes scarce and allows easier access to them. Killer whales are moving into the Arctic regions, which is a new habitat for them. Life below the surface is changing rapidly in a part of the world we are only beginning to understand.
Marine Life & Oceans Photos
Fish in a warming arctic
Life in the Arctic seas is changing. Climate has warmed an average of over 2 degrees celsius in the Arctic, more than twice the warming of the rest of the planet, and the water of this region has changed as a result. Sea ice has diminished dramatically, melting earlier in the year and building later. This changes the way marine animals live and the way they are hunted. Warmer Atlantic water has moved northward, bringing with it species not normally found in the Arctic, like cod and orca. Capelin, a major food source for many marine animals, whales and birds have declined because they are now hatching after their food source has peaked. The increased population of cod may be affecting capelin populations because they too, eat capelin. Halibut have grown smaller, likely due to overfishing, a consequence of the change in sea ice coverage. Even the smallest creatures have been impacted. Because they thrive in the higher CO2 waters, a result of the ocean’s absorption of anthropogenic CO2 from the atmosphere, smaller phytoplankton are consuming the nutrients needed by their larger cousins. This, in turn, impacts food supplies for whales that survive on plankton. Even the ocean’s natural ability to absorb more CO2 is effected. Everything is connected and humans have pulled on the strings of many aspects of the Arctic ecosystems.
Elegance of the Narhwal
The tooth of the narwhal has long held us in thrall. They appear to be mythical creatures, in part because they are so mysterious. Living in the coldest ocean, on top of the world, secluded and hidden, scientists have only recently begun to study them in earnest. Sometimes called the mountain gorilla of the Arctic, because their numbers are relatively few and their habitat incredibly specific and limited, narwhal are small, unique whales. The male’s tooth, which can grow to 8 feet long, once a mystery, is thought now to be a highly sensitized organ for providing information about the ocean conditions around them. It has been the prized possession of royalty for millennia, inspiring art and stories and collections. In Greenland, the narhwal are prized because their blubber contains very high amounts of vitamin C, a rare thing in the frozen north. Indigenous hunters are given a quota each year based on narwhal populations. This can be a contentious process when the number of narwhal to be hunted is low, as in Eastern Greenland, where many indigenous people depend on their valuable blubber to make a living. Narwhal are incredibly shy animals and have an extreme stress response to dangerous situations. There is concern among scientists that they will suffer in the new Arctic where shipping is increasing rapidly in new, ice-free routes, creating noise that can interfere with the communication and echolocation of narwhal and other whales. Resource extraction poses another threat to narwhal as the fish they eat can pass through waters polluted with mining runoff and pollution from oil and gas extraction. Orca have been seen deep in Arctic waters, a new habitat for them. They hunt narwhal, who are unaccustomed to their ubiquitous presence, and have fewer places to hide with diminishing sea ice. This majestic creature will need care to protect their habitat and way of life.
Marine Life & Oceans Articles
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Capelin are described a “lynchpin” species because a healthy population helps other types of fish. Cod and turbot eat them directly, and without lots of capelin those fish will eat commercially valuable crab and shrimp instead. Scientists blame late spawning for the population drop.