Threats to Whale Populations:
Whales are susceptible to entanglement in commercial fishing gear. This can slow whales down, weakening them and can prohibit them from feeding; leading to eventual starvation and death. In some areas, networks are set up to disentangle whales that are reported to be in trouble. The North Atlantic Right whale off the US East Coast is especially vulnerable to entanglement.
Commercial whaling began in the 1800’s and nearly drove some whale species to extinction. Some species have still not recovered from being hunted and are currently listed as endangered. Although commercial whaling is not the biggest threat facing whales today, it still exists. In the Southern Ocean, despite being a whale sanctuary, some nations are still hunting there, killing more than 1,000 whales each year despite it being illegal.
Climate change has a multitude of effects on the oceans which can have adverse impacts on marine mammals. Most large whale species depend on krill, a small shrimp-like crustacean, and fish as prey. As ocean temperatures rise from climate change, prey populations can be affected. Climate change also affects ocean currents altering prey distribution, feeding grounds and migratory pathways of whales. Other threats include but aren’t limited to; ingestion of marine debris, oil and gas development and disturbance by recreational watercraft.
The continuous issues with chemical pollution in the ocean combined with oil spills and garbage continues to influence recovering whale populations, however dolphins that live close to the coastline or in rivers may face even more ecological threats. In addition to chemical pollution and garbage, whales may also be affected by noise pollution from man-made equipment such as loud jet engines, sonar, underwater explosives and other types of equipment that can interfere with echolocation or cause damage to the whales hearing.
The construction of bridges, dams, waterways and other structures may affect travelling whale pods by separating groups of whales and preventing them from being able to meet up with friends and family.
Overfishing is when a company continues to fish to the point where it has an ecological impact on the sustainability of a particular population of fish or another ocean animals. In certain areas overfishing is making it difficult for whales and other marine mammals to find sufficient food sources causing these marine mammals to leave or possibly starve.
NOTE: The only natural predators to whales (besides humans) are attacks from a pack of hungry killer whales.
Even though killer whales are known to attack whales on rare occasions their attacks are so few that they cannot be considered a cause of the endangered whale species.