1. Loss of waterproofing: Oils destroy the natural waterproofing of feathers, causing them to clump and lose their insulating properties. This leads to loss of buoyancy, making it difficult for birds to stay afloat and escape predators.
2. Hypothermia: Wet, oiled feathers provide poor insulation, leading to hypothermia, especially in colder climates.
3. Reduced mobility: Matted feathers restrict movement and make it difficult for birds to fly, swim, and forage for food.
4. Ingestion of oil: Birds can ingest oil while preening their contaminated feathers. This can lead to poisoning, internal damage, and disruption of various bodily functions.
5. Disruption of feeding: Oiled beaks can impair a bird's ability to eat and drink properly.
6. Reduced buoyancy and diving能力: Oiled birds have difficulty diving and swimming due to the weight and reduced water-repellent properties of the oil-soaked feathers.
7. Toxins: Some oils, such as crude oil, contain toxic compounds that can cause damage to the respiratory system, liver, and other vital organs.
8. Secondary infections: Oiled birds are more susceptible to secondary infections and diseases, as the oil reduces the effectiveness of their natural defenses and compromises their immune system.
9. Stress: The overall stress of being oiled can further weaken the bird and exacerbate the effects of other factors.
As a result of these challenges, heavily oiled birds often have reduced chances of survival and may succumb to the combined effects of hypothermia, starvation, and toxicosis.