Garbage
Entangled fur seal.
It is not uncommon to see garbage in parks, along roadsides, etc. and although litter in water bodies is not as visible, it is a very significant problem. Garbage pollutes the whales’ home, making it unclean and unsafe. Cruise ships, cargo ships and fishing boats have been dumping garbage into oceans for years. Garbage from land, especially littered beaches, makes its way into oceans too. Garbage in oceans can be carried by water currents thousands of kilometres from where it is first dumped. Pieces of litter that are not biodegradable float around oceans for years and years.
Sometimes, marine animals mistake garbage for food and eat it. Plastic bags in animals' stomachs make them feel like they are full, and as a result, they don’t eat. And some plastics contain resin or chemicals that make animals sick.
Find out what happened to an entangled right whale off the coast of Nova Scotia or, check out the Centre For Coastal Studies' Whale Rescue section.
Chemicals
One of the most serious long-term threats to whales appears to be contamination by toxic chemicals. Harmful chemicals come from many different sources. Some toxic substances are made by nature, many are made by human activities. A number of hazardous chemicals originate from industrial and agricultural activities. Some chemicals are released directly into oceans or rivers and some come from far away sources. Water can carry chemicals down rivers, through oceans and even underground. Wind can carry chemicals over land and water.
Chemicals enter a whale’s system in a few ways: they are absorbed through the skin; they are consumed in contaminated food (fish and crustaceans); and they are passed on to calves through the mothers’ milk.
Different chemicals can have different negative effects on whales including: decreased reproduction, decreased resistance to disease, decreased growth, organ damage and interference with normal neurological and metabolic functions.
Fast Fact :
Belugas in the St. Lawrence River, in Quebec,
are one of the most polluted animals on Earth.
Their bodies contain such a high concentration
of PCBs and DDT that dead belugas are considered
hazardous waste!
Noise
Hearing is the most important sense to whales. They use hearing and sound for navigation, communication and locating prey. Shipping traffic and industrial activities, such as offshore oil drilling and the use of explosives in oil exploration, can create a lot of noise underwater. A whale’s ability to echolocate and communicate can be severely affected from high levels of underwater noise.
Fast Fact :
To communicate, humpback whales can send sounds over hundreds of kilometres! The males make the longest and most complicated songs of all the animals in the animal kingdom. To us these songs sound like whistles or deep rumbles.
Listen to more whale sounds.
