Gull the exceptions being Sabine's gull and swallow-tailed gulls, which have forked tails, and Ross's gull, which has a wedge-shaped tail. Gulls have moderately long legs, especially when compared to the similar terns, with fully webbed feet. The bill is generally heavy and slightly hooked, with the larger species having stouter bills than the smaller species. The bill colour is often yellow with a red spot for the larger white-headed species and red, dark red or black in the smaller species. The gulls are generalist feeders. Indeed, they are the least specialised of all the seabirds, and their morphology allows for
Fork-tailed storm petrel a species that feeds on surface material and follows ships, this storm petrel often ingests oil and plastic with their food items. Surprisingly, the fork-tailed storm petrel is relatively unaffected by the toxicity of oil, as their natural diet contains substances that are very chemically similar. Plastics also do not severely affect the birds because they can be regurgitated after ingestion. In contrast, being a top marine predator, fork-tailed storm petrels are susceptible to bioaccumulation. High lead concentrations have been found in the bones of petrels, and DDT can cause eggshells to become dangerously thin. The greatest threats that face