Waved Albatrosses produce such slow-growing, needy offspring that females lay only a single egg every two years. And both parents need to share the load until youngsters can hunt on their own. Albatrosses tend to pair for life, and reunited pairs go through an elaborate, synchronized…

Waved Albatrosses produce such slow-growing, needy offspring that females lay only a single egg every two years. And both parents need to share the load until youngsters can hunt on their own. Albatrosses tend to pair for life, and reunited pairs go through an elaborate, synchronized…

It’s a challenge for birds to sing through the loud hum of traffic. Many just belt it out, but not all birds. Great Tits, Song Sparrows and House Finches that live in a city sing at a higher pitch than their country cousins. And European Robins in cities sing more at night, when there is…

It’s a challenge for birds to sing through the loud hum of traffic. Many just belt it out, but not all birds. Great Tits, Song Sparrows and House Finches that live in a city sing at a higher pitch than their country cousins. And European Robins in cities sing more at night, when there is…

Some birds woo a mate by building the best nest. Males of many weaverbird species construct a series of intricately woven nests to impress a prospective partner. A male Red-winged Blackbird can even attract multiple mates if he controls prime breeding territory. Adélie Penguins construct…

Some birds woo a mate by building the best nest. Males of many weaverbird species construct a series of intricately woven nests to impress a prospective partner. A male Red-winged Blackbird can even attract multiple mates if he controls prime breeding territory. Adélie Penguins construct…

Male birds are often the larger, flashier sex that courts choosy females, who in turn raise their chicks. But not always. Female phalaropes -- like this Wilson's Phalarope -- challenge each other over territories in which to house a cluster of males half their size. And the males do all…

Male birds are often the larger, flashier sex that courts choosy females, who in turn raise their chicks. But not always. Female phalaropes -- like this Wilson's Phalarope -- challenge each other over territories in which to house a cluster of males half their size. And the males do all…

Birds have many ways of showing affection for their partners. One way is allopreening, where a bird uses its bill to groom a mate, twirling each individual feather in its beak (like these Macaws.) Other birds present their partners with gifts like moss or sticks. A female Arabian Babbler…

Birds have many ways of showing affection for their partners. One way is allopreening, where a bird uses its bill to groom a mate, twirling each individual feather in its beak (like these Macaws.) Other birds present their partners with gifts like moss or sticks. A female Arabian Babbler…