Attracting a mate is essential if you are going to pass your genes down to the next generation. Many animal species have fascinating, and sometimes borderline bizarre, ways of attracting a mate or at least signaling that they are open to offers. Take the American great white pelican, for example. They undergo changes to their bills, which serve as a very visible advertisement to attract a mate. Here, we will explain exactly what these changes are and how they help these birds form mating pairs.
American Great White Pelican Breeding
American great white pelicans are found throughout North America in coastal areas such as bays and estuaries. Breeding, however, takes place on islands located in or near shallow, inland lakes, rivers, or marshes in inland regions. Often, these breeding areas are at least 30 miles from where the birds usually forage for fish, crustaceans, and small amphibians.
Here, the birds establish small nesting territories where they will jab at other birds with their bills. Two chalky-white eggs are laid two days apart and incubated for about 30 days. First, however, they need to find a mate! These birds form monogamous pairs, and the hunt for a suitable partner begins as soon as they arrive at the breeding colony. Courtship displays are performed to demonstrate the health and strength of the hopeful candidate. These can include circular flights, parallel strutting walks, head swaying, and bowing.
Physical Changes During Breeding
The caruncle advertises readiness for breeding.
©Glass and Nature/Shutterstock.com
These birds also signal their readiness to breed with a physical change to their bills. American great white pelican bills are either peach-colored or yellow. During the breeding season, both males and females grow a protuberance (or horn) on their upper bill. It is called a caruncle and is a fibrous, epidermal plate. It grows vertically about one-third of the distance from the tip of the bill. It starts to grow just prior to the breeding season and falls off afterward.
Caruncle growth is probably triggered by hormonal changes in preparation for breeding. Having a large caruncle is considered a desirable characteristic. It demonstrates health and high sex hormone levels, which are what these birds want in a mate. Different types of caruncles are found on different parts of the body in other breeds of birds, including turkeys. At the end of the breeding season, the caruncles fall off, and you may even find them on the ground.
The post Pelicans With Horns? The Wild Way These Birds Attract Mates appeared first on A-Z Animals.
