Habitat loss and degradation: Harbor seals rely on coastal habitats, including estuaries, bays, and rocky shores for breeding, pupping, and feeding. Human activities such as coastal development, dredging, and pollution have led to the degradation and fragmentation of these habitats, reducing the available space and resources for harbor seals.
Hunting and bycatch: Harbor seals have been historically hunted for their fur, meat, and blubber. Despite regulations in many countries, illegal hunting and bycatch in fishing operations still occur, posing a threat to harbor seal populations.
Climate change: Rising sea levels, changes in ocean currents, and reduced sea ice due to climate change can disrupt harbor seal habitats, food availability, and pupping sites. This can lead to population declines, especially in areas already experiencing environmental stress.
Disease: Harbor seals are susceptible to various diseases and parasites, including canine distemper virus, phocine distemper virus, and bacterial infections. Disease outbreaks can cause high mortality rates, particularly among young pups, leading to population declines.
Competition and predation: Harbor seals compete with other marine mammals and fish species for food resources. In some areas, they may also be preyed upon by sharks, killer whales, and other predators, contributing to population control and potential threats.
Human disturbance: Increased human activities in coastal areas, such as boating, tourism, and noise pollution, can disturb harbor seals and disrupt their natural behaviors, including feeding, breeding, and resting. This can have negative effects on their survival and reproductive success.