Harm to these benthic organisms is not only any issue to these organisms themselves, but also to the many surface-dwelling organisms higher up in the food chain who suffer when their food becomes contaminated or scarce. The route by which an animal is exposed to oil ingestion, absorption, or inhalation can also influence the rate and toxicity of the effects. Animals with varied diets may have fairly limited contact with oil through the ingestion route, whereas low-mobility animals that need to breathe at the surface will have high rates of exposure through inhalation due to their limited ability to escape the extent of the spill.
The age and overall health of an animal may influence the degree of harm caused by exposure to an oil spill to that animal. Individuals of lower fitness are likely to be impacted to the greatest extent by the additional stresses imposed by an oil spill. In general, eggs, larvae, and early juvenile life stages are more susceptible to oil and to chemical dispersants than are adult animals of most species. Depending upon their reproductive states at the time of a spill, the exposure of a population of animals to oil will influence the degree of harm for the population as a whole.
If many larvae or juveniles die the year a spill occurs, for instance, the capacity of the species to rebound the following year will be lowered because many fewer reproducing individuals will be present.
Finally, the types of synthetic materials used by response teams to clean up or disperse oil can influence the magnitude of harmful effects to wildlife. Often "dispersants," detergent-like surfactants, are applied to an oil spill site to increase the rate of degradation of oil.
The use of these dispersants can reduce exposure to harmful effects caused by the inhalation of toxic materials by animals visiting the surface to breathe, and can reduce impacts to shoreline habitats. However, these materials may increase the harmful effects of oil on the insulation abilities of bird feathers. Dispersants also cause oil particles to disperse deeper into the water column where the oil may harm populations of benthic animals in deeper waters.
The vulnerability of various species of wildlife to an off-shore oil spill changes as time since the spill increases. Species that spend time at the surface of the water will be impacted most during the early stages of the spill. Once the oil begins to wash ashore, species that forage and nest along the shoreline are affected.
Finally, influence on benthic species begins once the oil particles leave the surface and become mixed throughout the water column. Mammals are susceptible to harm from oil spills through a variety of means. Mammals with fur become vulnerable when oil coats their fur and prevents it from providing insulation from cold temperatures.
Fortunately, mammals in the Gulf of Mexico, such as whales, manatees, and dolphins, are hairless and therefore less likely to suffer the dire consequences faced by sea otters and fur seals exposed to oil spills at more northern latitudes. However, animals without fur can experience irritation and increased likelihood of infection when exposed to oil.
Also, the whales, manatees, and dolphins found in the Gulf of Mexico must come to the surface to breathe, which increases their risk of exposure to inhalation of volatile compounds. Baleen whales, such as Bryde's whales, may face difficulties filtering food through their baleen if they forage in areas with oil. Birds are primarily affected through damages oil causes to their plumage and through ingestion. Oil reduces the ability of bird feathers to provide insulation, which increases their risk of hypothermia in cold climates.
Rate of heat loss is much higher in the water than in air, so oiled plumage is particularly problematic for birds that must find food in the water, such as seabirds, cormorants, and grebes. In extreme circumstances, oil-soaked birds are unable to fly or remain afloat because the oil has reduced both the insulation and the waterproofing of the feathers.
Birds with oiled feathers are likely to have reduced survival rates because of difficulties obtaining food and escaping from predators. Oil can also be ingested directly by birds that feed on contaminated prey or while preening. As the coverage of oil on a bird increases, so does the amount of preening and the amount of oil ingested. Sea turtle adults are probably most susceptible to oil spills through inhalation when they surface to breathe, or through ingestion of oil-fouled food and floating tar balls they mistake for food.
Sea turtles have a habit of ingesting floating objects, regardless of their nutritional value. Eggs and hatchlings are susceptible through absorption. Three of the five species of sea turtles occurring in the Gulf of Mexico are endangered Kemp's Ridley, Leatherback, and Green , whereas the other two are threatened Loggerhead, Hawksbill. Nesting season for these species begins in the spring, which means that eggs and hatchlings are likely to experience high risk of exposure to oil spills that occur this time of year.
The Gulf of Mexico is home to a rich abundance of wildlife, including many threatened and endangered species. Seven large oil spills have occurred in the Gulf of Mexico during recent times, providing important insight on how best to manage such catastrophes to minimize harmful effects to wildlife.
Alonso-Alvarez, C. Perez, and A. Effects of acute exposure to heavy fuel oil from the Prestige spill on a seabird. Aquatic Toxicology — Ben-David, M. If your life has been adversely affected by an oil spill, contact an attorney as soon as possible. You may be entitled to compensation for loss of wages and property damage. More Contact Info. Oil Spill Effects. Marine Life Waterfowl, fish, plants, and living organisms suffer serious health effects after oil spills. Oil can be ingested, inhaled, and absorbed by marine life Birds, Fish, and Sea Mammals Oil spills are particularly devastating to species that depend on the health of the ocean for their own survival.
The health effects of oil spills include: Hypothermia: contact with oil can harm the insulation of feathers and fur, leaving birds, sea otters, and seals vulnerable to hypothermia. Poisoning: Sea mammals, birds, and fish can be killed or sickened if they ingest or inhale oil; smaller organisms such as plankton can be contaminated, poisoning species further up the food chain.
Drowning: Birds who have come into physical contact with oil slicks can get weighed down by the substance and drown. Disturbed breeding grounds: Fish eggs and larvae, as well as bird eggs, are sensitive to toxins and can be damaged by oil spills; birds and fish that are exposed to oil often experience impaired reproductive abilities.
Deformities: Marine life may suffer from deformities such as stunted growth, fin abnormalities, fertility problems, and other impairments. Other damage: Marine life's respiratory, cardiac, and immune systems can be compromised due to oil spills. Many birds and animals also ingest oil when they try to clean themselves, which can poison them. Fish, shellfish, and corals may not be exposed immediately, but can come into contact with oil if it is mixed into the water column — shellfish can also be exposed in the intertidal zone.
When exposed to oil, adult fish may experience reduced growth, enlarged livers, changes in heart and respiration rates, fin erosion, and reproduction impairment.
Fish eggs and larvae can be especially sensitive to lethal and sublethal impacts. Even when lethal impacts are not observed, oil can make fish and shellfish unsafe for humans to eat.
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