|White pelicans are returning in number to Upper Mississippi River National Wildlife and Fish Refuge. Here, they share an island with five other colonial nesting bird species.|
|Credit: Stan Bousson|
Pelicans Return to Upper Miss Refuge
The great whites are back. No, not sharks. American white pelicans — efficient fish trawlers that are returning in number to the Upper Mississippi River National Wildlife and Fish Refuge, where they are gobbling up local sushi with gusto. This year, the summer migrants numbered 3,000, up from a few hundred a few years ago.
Small groups of pelicans first arrived on the refuge in the early 1990s, summering along the Mississippi River sand bars. The population slowly edged up but no nesting was observed.
Then came a breakthrough: In 2007, biologists documented the first nesting colony of pelicans since 1909 on two Mississippi River islands in Iowa; the northern colony produced 50 young. Despite flooding, pelicans returned to the islands to nest the following spring, and the number of young increased to 200. In 2009, the colony produced 400 young and expanded eastward to form the first documented nesting colony in Illinois. This year, the colony doubled in size, producing 825 young.
Pelicans, large birds that stand five feet tall and weigh up to 15 pounds, can live for more than 10 years. They have black wing tips and a large yellow/orange pouch. A knob protrudes on the upper bill in adults during the early nesting season.
A pelican’s nest consists of a slight depression in the sand rimmed with sticks or other debris. Pelicans lay two to four eggs; pink hatchlings emerge after about a month. When approached by humans, young pelicans make a low grunting or croaking sound. If you get too close, they forcefully spit out a half-digested fish soup; the stench is usually enough to stop intruders. But the defense strategy doesn’t eliminate all the risks from living near humans: Entanglement in fishing lines is a constant danger.
On the refuge, the pelicans have formed a distinctive social network with other colonial nesting birds. The pelicans have taken up residence alongside a nesting colony of great egrets, cattle egrets, great blue herons and double-crested cormorants. All five species are social nesters but occupy different habitats on the island: The pelicans are ground nesters. The egrets and herons nest midway in trees. Cormorants nest at the top of trees.
White pelicans are primarily fish eaters but also enjoy a tasty frog, salamander or aquatic insect. They do not plunge dive from the sky like their cousins, brown pelicans. Instead, they feed independently or swim in a group to herd fish and then scoop them up in their oversized pouches. A pelican can eat several pounds of fish per day. While some local fishermen complain the pelicans have decreased their catch, studies have shown that in a big river system, pelicans have no significant impact upon fish populations.
For more information on Upper Mississippi River National Wildlife and Fish Refuge, a breeding and resting place for birds that runs through four states (Minnesota, Wisconsin, Iowa and Illinois), visit http://midwest.fws.gov/UpperMississippiRiver/.