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Class One: Seabird Basics

What makes a seabird a seabird?

A seabird is a that spends most of its life at . Although all seabirds breed on land, they find their food out at sea, and some even sleep on the water.

Despite huge variation among different , they all share similar characteristics.

They are all adapted to life at sea.

Seabird

Glands. Imagine drinking only sea-water! Seabirds need to a way to get rid of all this salt, and most species have salt glands on their head that concentrate all the salt that the take in through their water and food. When lots of salt has built up, it either flows out of the gland (out the nostril), or the bird “sneezes” it out!

• Dense Bones. Many diving seabirds (like ) have dense bones to reduce when they dive deep for food.

• Feet and Legs. The shape and size of feet and legs can tell us a lot about how seabirds feed and spend their time. Species that spend a lot of time on the (like ) usually have short, strong legs and webbed feet that act as paddles.

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. shape can also tell us a lot about a seabird’s feeding behavior. Diving species have short wings. Some species, like penguins, can’t fly at all! Instead, their short, strong wings act as flippers and the birds “fly” underwater to catch their prey.

Tufted Puffins are also diving birds with short wings. They can still fly, but they have to flap their wings most of the time (they have been described as flying like a bumblebee) and this takes a lot of energy.

Species that cover great distances over the open ocean and catch their prey near the surface of the water have long slender wings that help them glide on the wind. The Wandering has the largest wingspan (wing tip to wing tip) of any living bird. Over 11 foot! Compare this wingspan to the height of yourself!

WWandering Albatross:

• Spend most of their life flying.

• One banded bird was recorded travelling 6000km in 12 days!

• Live for over 50 years

• Mate for life

• Breed every 2 years . © Mario QU, via Creative Commons.

Tufted :

• Breed throughout the North Pacific Ocean

in a dug with their bill and feet

• Lay one

• Feed on , and invertebrates

• Bring multiple fish back to their . © Myer S. Bornstein, via Creative Commons. chick at the colony in their bill. [email protected] www.seabirdyouth.org 2

• Waterproof Coat. Many seabirds spend most of their life in very cold water. They have thick layers of down and to keep them warm and dry, and a special gland that releases oil to keep feathers waterproof.

• Head Structure. Some species, like the and , have specialized to their head (strong bills, thicker bones, and air sacks) so that they can survive their high impact diving.

Gannets diving for food. Keith Marshall, via Creative Commons.

• Gannets breed in the North Atlantic.

• They plunge-dive for fish, diving into the ocean from heights up to 130 feet!

• Gannets reach speeds of 60-90 mph when they hit the water!

• They gulp in air as they descend, and fill up air sacks around the neck and shoulder to protect them when they hit the water. [email protected] www.seabirdyouth.org 3

Seabird Behavior

Seabirds also have specialized behavior to help them live and feed in the marine environment.

• Diet. Seabirds eat primarily fish, squid, and .

• Long-lived. Most seabirds live a long time (between 20-60 years!)

• Few chicks. In general, seabirds also have fewer chicks (1-3) than other species of land birds, and often don’t start breeding until later on in life (2-10yrs old).

• Hard-working parents. Parent seabirds spend a lot of time and effort rearing their chick. For example, parents of some of the larger albatross species feed their chick at the colony until they are 10 months old.

Living for a long time and having fewer chicks per year has likely evolved because of their unpredictable marine conditions, challenges of finding food at sea, and the relative lack of compared to land-birds.

Where do seabirds live?

Seabirds can be found worldwide, from the tropics to both polar-regions. We all know that penguins live in the snowy Antarctic, but did you also know they live in Australia and South Africa?

• African Penguins live on the SW of Africa. • They dive on average 30 meters deep (but can dive as deep as 130 meters!). • They live for about 10 years, but don’t start breeding until they are 4 years old. • They lay 2 in a nest burrowed in African or sand.

© Robert Cave, via Creative Commons

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Main groups of seabirds (seaducks, , , and are sometimes also included as seabirds)

• Penguins. All are highly adapted to

underwater travel, but cannot fly. Except for the Galapagos Penguin, they all live in the

Southern Hemisphere (but not all live where it is very cold) Rock hopper Penguin. Mark “Clancy”, via Creative Commons

• Alcids. This group of species (family Alcidae) both fly and swim with their wings. They live only in the Northern Hemisphere. The Great is now extinct. Species of alcid include . Ram Papish the puffins, murres, and auklets. ©

• Tubenoses. All tubenose species (Order Procellariformes) have their nostrils enclosed

in tubes. They include the albatross, , , and prions. . Chrysoptera, via Creative Commons.C

• Other seabirds. This order () includes the gannets, , boobies, tropic

birds, , and frigate birds. Frigate Bird. D200-Paul, via Creative Commons

-like birds. The , jaegers, , and (family )

Sooty . Arthurgrosset, via Creative

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Seabirds breeding on the Pribilof Islands

An estimated 2. 8 million seabirds nest on the Pribilof Islands. Due to the importance of these colonies, the islands were included in the Alaska Maritime in 1984.

Alcids

• Thick-billed Murre •

• Tufted Puffin Alaska • Pribilof • Least Auklet Islands •

Gull-like Birds Map showing location of the Pribilof Islands in Alaska. • Black-legged The islands are located north of the , in • Red-legged Kittiwake the middle of the Bering Sea. Tube-noses

Other seabirds

• Red-faced Cormorant

http://alaska.fws.gov/mbsp/mbm/seabirds/species_list.htm This website has links to detailed accounts on all the seabirds species breeding in Alaska. [email protected] www.seabirdyouth.org 6 Follow the steps below to see what seabird species breed on the Pribilofs

1) Go to www.seabirds.net/

2) Click on “Resources”

3) Click on “Seabird Information Network” and you’ll see a list of shared seabird databases

4) Click on “Circumpolar Seabird Data Portal”, then click “enter application”

5) You should see the world map appear. You can use the computer mouse to move around on this map. Find North America… then Alaska… then the Aleutians…

6) You can then click on the zoom (+) button… and find the Pribilof Islands.

7) Keep all the species shown on the right hand side checked, but uncheck seabird index.

8) You can zoom right in on the Pribilofs, and will see that there are four colored circles (St. Paul, St. George, Otter and Walrus Island)

9) Two of the circles (St. Paul and St. George) have a blue/green ring around them. This means there are productivity and population trend data available for these two colonies (but less is known about the birds on Otter and Walrus islands).

9) Place your curser over St. Paul, and make a note of how many Least Auklets there are.

10) Do the same for St. George.

11) Which island has the most Least Auklets?

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