Sea birds 🌊🦆

Hey everyone!
Today I'm going to describe sea birds. I hope you will be interesting in sea birds.

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Sea birds are first known to occur in the cretaceous period. In late Miocene and Pliocene has the highest diversity of sea birds. In 9700 species of birds are distributed. 300 species are marine birds. 20% of sea birds are globally threatened. All sea birds are in class Aves. Birds live throughout the world's oceans and shorelines from the equator to the poles.

Birds that depend on the ocean for their survival are commonly referred to as sea birds. Sea bird has various types of anatomical changes to the survive their marine environment. All birds have feathers but sea birds have water repel down feathers to protect. Some birds consist of special types of the gland to produce water proof oil. They use their beak to spread this oil. Surface swimmers and flying birds have lightweight hollow bones. Diving birds have denser bones.
Eg: Penguin
Diving birds have air sacs. They can remove air from air sacs to reduce buoyancy. More pelagic birds consist of lower and linger wings but diving birds have longer wings.
Most birds are colorful. Did you see marine birds /sea birds are colorful?? No, it is not. Their feathers are less colorful ( black, gray, white).

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In their anatomy, they have adapted for food and feeding. There are beak modification, digestive track modification, locomote appendages, sense organs (behaviors).

Sea birds have a swimming and diving adaptation for their locomotion. Swimming bords consist of wide-body and dense plumage provide buoyancy. The feet can be either webbed or lobed. There are two types of webbing. Palmate webbing (webbing between 3 forward toes) and Totipalmate webbing (webbing between all 4 toes).

Diving birds have further specialization in hind limbs. Modification wings are used as a flipper underwater.
Buoyance should be overcome by diving birds. The interesting thing is Penguins swallowing small tones before diving. They act as ballast.

Sea birds have physiological adaptations to diving. They want more energy to dive. Therefore they reduce the metabolic rate and heart rate in underwater. They have a large blood volume as well as a high oxygen concentration in their body. They can produce considerable energy from anaerobic metabolism.

Some birds make colonial nesting. The colony is concentration of potential prey which can attract predators but the density of nesting may provide a degree of protection.

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Sea birds migrate over a huge distance in their lifetime. Sea birds often migrate after their breeding season. Some birds migrate a shorter distance away from the breed sites, their distribution at sea determine by the availability of food.

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