# Knob-billed Duck (*Sarkidiornis melanotos*) The Knob-billed Duck is a unique bird with a big, funny knob on its bill! It loves to swim in lakes and rivers, and its beautiful feathers can be black and white. - **Category:** [Birds](https://www.snappit.app/explore/categories/bird) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Habitat:** Wetlands - **Also known as:** African Knob-billed Duck ![Knob-billed Duck](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Knob-billed_Duck_at_Sonkhaliya%252C_Rajasthan%252C_India%252C_July_2013.jpg&width=800) Photo: Koshy Koshy, CC BY 2.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Knob-billed_Duck_at_Sonkhaliya%252C_Rajasthan%252C_India%252C_July_2013.jpg) ## Appearance The Knob-billed Duck has an iridescent black back and head, contrasting with a clean white belly and grey flanks. Males feature a large, prominent black knob atop their bill, which is noticeably larger during the breeding season. Its large size and unique bill knob make it easily identifiable among other waterfowl. ## Taxonomy - **Kingdom:** Animalia - **Phylum:** Chordata - **Class:** Aves - **Order:** Anseriformes - **Family:** Anatidae - **Genus:** Sarkidiornis ## Interesting facts - Males develop a dramatic, oversized knob on their bill when it's time to find a partner! - Sometimes, multiple female Knob-billed Ducks will share one giant nest for their eggs! - Their feathers shimmer with beautiful green and purple colors in the bright sunlight. - These ducks often lay their eggs in tree hollows, a very unusual nesting spot for ducks. ## Special abilities - **Water Wizardry:** Knob-billed Ducks can dive deep underwater to find food because of their strong, webbed feet that help them propel through the water. - **Magnet Mouth:** The male Knob-billed Duck has a prominent fleshy knob on its bill that grows larger in breeding season, which helps attract a mate. - **High-Flying Power:** Knob-billed Ducks possess strong wings and streamlined bodies that enable powerful, swift flight, helping them travel between wetland habitats. ## Measurements & details - **Length:** 56-76 cm - **Wingspan:** 105-145 cm - **Weight:** 1.2-2.9 kg - **Lifespan:** 5-10 years - **Speed:** 60 km/h - **Clutch Size:** 7-15 - **Incubation:** 28-30 days ## Diet & Feeding They eat mostly plants, seeds, and aquatic insects found in wetland areas. - **Primary Foods:** aquatic plants, seeds, grasses, insect larvae, small fish, mollusks - **Foraging Method:** Foraging ## Ecological connections - **Eaten by:** Nile Crocodile (*Crocodylus niloticus*) — Large crocodiles sometimes prey on adult ducks or ducklings. - **Eaten by:** African Fish Eagle (*Haliaeetus vocifer*) — Fish eagles are powerful raptors that hunt ducks. - **Eats:** Egyptian White Waterlily (*Nymphaea lotus*) — Ducks consume seeds and parts of this common water plant. - **Eats:** [Rice](https://www.snappit.app/explore/rice) (*Oryza sativa*) — Found feeding on rice grains and sprouts in paddies. ## Traits - [Feathered](https://www.snappit.app/explore/traits/feathered): Feathered describes animals, primarily birds, possessing a covering of feathers. - [Webbed Feet](https://www.snappit.app/explore/traits/webbed-feet): Characterized by having toes connected by a membrane, typically aiding in swimming. - [Social](https://www.snappit.app/explore/traits/social): Social animals live in organized groups, cooperating for survival benefits such as foraging, defense, and raising offspring. - [Colorful](https://www.snappit.app/explore/traits/colorful): Colorful describes organisms or objects displaying a wide range of bright and distinct colors. - [Filter Feeder](https://www.snappit.app/explore/traits/filter-feeder): Filter feeders obtain nutrients by straining suspended food particles and small organisms from water. - [Herbivorous](https://www.snappit.app/explore/traits/herbivorous): This trait characterizes organisms whose diet consists entirely or primarily of plant material. - [Wetland](https://www.snappit.app/explore/traits/wetland): This habitat trait identifies species found in wetlands, which are areas of land saturated with water, either permanently or seasonally, including marshes, swamps, and bogs. - [Diurnal](https://www.snappit.app/explore/traits/diurnal): Diurnal animals are primarily active during daylight hours, typically resting or sleeping at night. - [Freshwater](https://www.snappit.app/explore/traits/freshwater): Freshwater habitats include non-saline aquatic environments such as rivers, lakes, ponds, and wetlands, vital for numerous species. ## Collections - [Birds](https://www.snappit.app/explore/collections/birds) ## Safety **Danger:** 1/5 · Very low Always watch ducks from a distance and do not feed them bread. ## Frequently Asked Questions ### How to identify Knob-billed Duck? Compare the silhouette, bill shape, tail length, wing bars and markings around the eyes. The same small brown bird at your feeder can look quite different in breeding plumage, winter plumage or its first year. Bird Identifier: upload a photo and compare the visible details. ### How long is Knob-billed Duck? 56-76 cm ### What is Knob-billed Duck's wingspan? 105-145 cm ### How much does Knob-billed Duck weigh? 1.2-2.9 kg ### How long does Knob-billed Duck live? 5-10 years ### How fast can Knob-billed Duck move? 60 km/h ### What does Knob-billed Duck eat? They eat mostly plants, seeds, and aquatic insects found in wetland areas. ### Where is Knob-billed Duck usually found? Wetlands ## More Birds - [Black-crowned Night Heron](https://www.snappit.app/explore/black-crowned-night-heron) (*Nycticorax nycticorax*) - [Anna's Hummingbird](https://www.snappit.app/explore/annas-hummingbird) (*Calypte anna*) - [Great Egret](https://www.snappit.app/explore/great-egret) (*Ardea alba*) - [Blue Jay](https://www.snappit.app/explore/blue-jay) (*Cyanocitta cristata*) --- Source: [Knob-billed Duck: Facts & Places to See — Snappit](https://www.snappit.app/explore/knob-billed-duck)