{"id":3530,"date":"2021-08-30T17:47:06","date_gmt":"2021-08-30T17:47:06","guid":{"rendered":"https:\/\/nwco.net\/?page_id=3530"},"modified":"2021-08-30T17:47:06","modified_gmt":"2021-08-30T17:47:06","slug":"pelican-biology","status":"publish","type":"page","link":"https:\/\/nwco.net\/?page_id=3530","title":{"rendered":"Pelican Biology"},"content":{"rendered":"

Identification\u00a0<\/a>|\u00a0Biology<\/a>\u00a0|\u00a0Damage ID<\/a>\u00a0|\u00a0Management<\/a>\u00a0| Resources<\/p>\n

Reproduction<\/h2>\n

Pelicans are believed to breed at\u00a0three years of\u00a0age. The breeding period typically is mid-April through mid-September.\u00a0Nest building takes 3\u00a0to\u00a05 days\u00a0after\u00a0the\u00a0onset of courting.\u00a0Egg\u00a0laying\u00a0begins about 4\u00a0to\u00a05 days\u00a0after nest site selection,\u00a0with an interval of 2 days\u00a0between eggs.\u00a0They\u00a0have one\u00a0clutch\u00a0of 2 eggs\u00a0per year.\u00a0\u00a0Smaller clutches often\u00a0are\u00a0due to egg loss\u00a0due to predation.\u00a0Due to asynchronous hatching and siblicide\u00a0(one young\u00a0bird\u00a0kills the other),\u00a0only one young typically survives to fledging.\u00a0Average documented nest success ranges from 0.34 to 0.89 young fledged per nest.\u00a0It is not\u00a0known if\u00a0pelicans\u00a0renest\u00a0following the loss of\u00a0a\u00a0clutch\u00a0early\u00a0in the season.<\/p>\n

Eggs\u00a0hatch approximately 30 days\u00a0after\u00a0being\u00a0laid and\u00a0the chicks\u00a0fledge\u00a0approximately 10\u00a0weeks later.\u00a0Both sexes attend the nest and young.<\/p>\n

Nesting Cover<\/h2>\n

American white pelicans are ground nesters and prefer remote, isolated islands for colony sites. These breeding sites vary from nearly barren to densely vegetated, but are usually near water. Nests are typically shallow depressions on the ground with a small raised edge made from the adult raking gravel, soil, or vegetation with its bill.<\/p>\n

Behavior<\/h2>\n

American white pelicans forage during both the day and the night. However, pelicans in south Louisiana and northwest Mississippi forage primarily during the morning and afternoon. Pelicans feed singly, in small groups (two to 25 birds), or in large groups of more than 25 birds. When foraging singly or in small groups, pelicans usually dip their bills to search for food as they swim. When cooperatively foraging, pelicans herd their prey toward shallow water by swimming side by side and synchronously dipping their bills. Pelicans have been known to fly up to 190 miles from a breeding colony to a feeding site and prefer to forage in shallow water. Catfish ponds provide a nearly perfect foraging environment for pelicans, due to the relatively shallow pond depth (approximately five feet) and high fish stocking densities.<\/p>\n

In\u00a0one study conducted in\u00a0south Louisiana and northwest Mississippi,\u00a0researchers found that\u00a0pelicans at catfish ponds spent about 4% of their day foraging and 96% loafing, whereas pelicans foraging in other habitats\u00a0(crawfish ponds, rivers, lakes, and bayous)\u00a0spent about 28% of their day foraging and 72% loafing.<\/p>\n

American White Pelicans are cooperative foragers. They often forage in large groups using synchronized movements to herd and capture prey (e.g., swim in a line and synchronously dip their bills). Pelicans use air temperature thermals during flight to reduce their energy expenditure. Birds flap and circle to gain altitude in a thermal. Then they release from the thermal and glide long distances, repeating the process until they arrive at their destination.<\/p>\n

Pelicans generally arrive\u00a0at their breeding colonies during April\u00a0to\u00a0May and remain through early to mid-September.\u00a0Fall migration usually takes place from mid-September through mid-November. Pelicans occupy their wintering areas from mid-November through the end of February. Spring migration typically takes place March\u00a0to\u00a0April.<\/p>\n

Habitat<\/h2>\n

Pelicans breed\u00a0and spend the summer months\u00a0on remote islands of freshwater lakes and forage in lakes, rivers, marshes, and aquaculture\u00a0facilities\u00a0year round.\u00a0Pelican\u00a0mean\u00a0home ranges\u00a0vary from\u00a0110\u00a0to\u00a02,927\u00a0square miles\u00a0in the summer\u00a0and\u00a0from\u00a0115\u00a0to\u00a0569\u00a0square miles in the winter.<\/p>\n

During migration,\u00a0pelicans typically fly along river corridors and valleys but do cross deserts and mountains. Pelicans often stop over at\u00a0waterbodies\u00a0that\u00a0provide\u00a0forage and loafing sites. Pelicans readily take advantage of aquaculture sites during migration\u00a0and on their wintering grounds.\u00a0While\u00a0on their wintering grounds pelicans use sand bars, mud flats, flooded agriculture fields, and abandoned fish ponds\u00a0as loafing sites.<\/p>\n

Food Habits<\/h2>\n

Pelicans\u00a0prefer\u00a0to\u00a0forage in shallow water (1\u00a0to 9.8 feet) in open areas of marshes, lakes, rivers, ponds, but are also known to forage in deeper water to take advantage of prey driven to shallower depths by diving birds such as cormorants. Pelicans are tip-up foragers;\u00a0they\u00a0do not submerge or dive. A pelican\u00a0cannot\u00a0forage deeper than\u00a0it\u00a0can extend\u00a0its\u00a0neck, head,\u00a0and bill. A typical pelican can easily reach to 3.3\u00a0feet\u00a0below the surface\u00a0of the water.<\/p>\n

Pelicans\u00a0typically feed on fish, crawfish,\u00a0and\u00a0amphibians,\u00a0ranging in size from\u00a01.6\u00a0to\u00a024.8 inches.\u00a0To forage, a pelican\u00a0dips its bill\u00a0into the water and scoops\u00a0prey into\u00a0its\u00a0gular\u00a0pouch,\u00a0then\u00a0raises\u00a0its\u00a0bill above\u00a0its\u00a0head to swallow. Pelicans prefer to forage for schooling prey but will forage for dispersed prey.\u00a0Pelicans\u00a0forage twice a day,\u00a0consuming\u00a0an average\u00a0of\u00a01.2 pounds per foraging trip. Researchers, however, have recorded a pelican consuming as much as 6.8 pounds in a single foraging event.<\/p>\n","protected":false},"excerpt":{"rendered":"

Identification\u00a0|\u00a0Biology\u00a0|\u00a0Damage ID\u00a0|\u00a0Management\u00a0| Resources Reproduction Pelicans are believed to breed at\u00a0three years of\u00a0age. The breeding period typically is mid-April through mid-September.\u00a0Nest … Continue reading Pelican Biology<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"parent":3523,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3530","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/pages\/3530"}],"collection":[{"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/nwco.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3530"}],"version-history":[{"count":1,"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/pages\/3530\/revisions"}],"predecessor-version":[{"id":3531,"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/pages\/3530\/revisions\/3531"}],"up":[{"embeddable":true,"href":"https:\/\/nwco.net\/index.php?rest_route=\/wp\/v2\/pages\/3523"}],"wp:attachment":[{"href":"https:\/\/nwco.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3530"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}