How Does Climate Change Affect Polar Bears

Threats to polar bears

Large carnivores are sensitive indicators of ecosystem health. A polar bear at risk is often a sign of something wrong somewhere in the Arctic marine ecosystem.

Climate change

Climate modify, and the loss of bounding main ice habitat, is the greatest threat to polar bears. The impacts of this change are felt kickoff and worst in the Arctic.

How does climate change touch polar bears?

Fewer opportunities to feed

Polar bears rely on ocean ice to hunt and shop free energy for the summer and autumn, when food tin be scarce. Ocean ice now melts earlier in the leap and forms later in the autumn in the bears' southern range, like Hudson Bay and James Bay in Canada. Equally the bears spend longer periods without food, their health declines. For every week earlier the water ice breaks up in Hudson Bay, bears come ashore roughly 10 kg (22 lbs) lighter and in poorer condition.

Fewer cubs

Unhealthy bears can mean lower reproduction rates, higher cub bloodshed – and eventually, local extinction. The main causes of decease for cubs are lack of food or lack of fat on nursing mothers.

Toxic pollution

As meridian predators, polar bears are exposed to high levels of pollutants through their food. The popular image is of polar bears living in a pure, frozen wilderness is misleading. The Chill food chain contains high levels of some toxic chemicals.

How do toxic chemicals touch on polar bears?

Disruption of biological functions

Bears with high levels of some POPs (persistent organic pollutants) have low levels of vitamin A, thyroid hormones, and some antibodies. These are important for a broad range of biological functions, such as growth, reproduction, and the ability to fight off diseases. Females with partially-adult male person sexual organs -- Pseudohermaphrodites -- accept been observed in i.v % of the polar bears sampled on Svalbard in contempo years. Scientists believe this could be the effect of long-range pollutants.

Danger to cubs

In some areas, the mother bears' milk contains particularly high concentrations of these chemicals. The milk can actually poison the cubs, leading to lower survival rates.

Oil exploration

The oil and gas business is increasingly moving into the Arctic as more accessible reserves in the s dry up. Polar acquit populations are expected to come up nether increased pressure if oil developments in the Arctic go ahead according to industry plans. Offshore operations pose the greatest take chances, since routine emissions, spills or leaks will exist discharged direct into the ocean or on the body of water ice.

How does oil exploration affect polar bears?

Reduced insulation

Contact with oil spills can reduce the insulating effect of the bears' fur. The deport must then use more than energy to keep warm, and compensate by increasing its caloric intake—which may be difficult.

Poisoning

Polar bears tin ingest oil through training and through eating contaminated casualty. The ingested oil can cause liver and kidney damage, and has long-term toxicity. Bears can be poisoned past fifty-fifty a limited amount of oil on their fur.

Disturbance

Seismic diggings, construction, transportation and operation of oil facilities tin can negatively affect polar bears.

Devastation of habitat

If a major oil spill occurs at or nearly areas with high concentrations of polar bear denning sites, for example Hopen Island in the Barents Ocean, information technology could have population-wide consequences.At that place is currently no proven constructive method for cleaning or decision-making an oil spill in icy, chill waters, where hard atmospheric condition conditions are common.