The knob-billed duck (Sarkidiornis melanotos), or comb duck, is an unusual, pan-tropical duck, found in tropical wetlands in sub-Saharan Africa, Madagascar and south Asia from Pakistan to Laos and extreme southern China. It also occurs in continental South America south to the Paraguay River region in eastern Paraguay, southeastern Brazil and the extreme northeast of Argentina, and as a vagrant on Trinidad.

It is the only known species of the genus Sarkidiornis. The supposed extinct "Mauritian comb duck" is based on misidentified remains of the Mauritian shelduck (Alopochen mauritianus); this was realized as early as 1897, but the mistaken identity can still occasionally be found in recent sources.
Comb Duck
Date Location Count
2021-02-25 07:32Etosha NP--Fischer's Pan Loop13
2021-02-14 15:49Okonjima Nature Reserve1
2021-02-26 08:06Shamvura Camp--boat trip1
2021-02-19 07:15Queen Elizabeth II NP--Lake Bunyampaka9
2021-02-07 06:20Magashi Peninsula4
2021-02-24 05:29Okavango Delta--Mombo/Little Mombo Camp120
2021-02-23 06:30Maasai Mara NR--Mara Triangle2
2021-03-05 07:17Lake Nakuru NP1
2021-03-07 07:40Ataye Wetlands
2021-03-06 06:41South Luangwa NP--Mfuwe Lodge
2021-02-26 14:31Tarangire NP--Entrance Gate2
2021-02-21 07:06Nairobi NP
2021-02-26 08:10Tarangire NP--Tarangire Safari Lodge2
2021-03-03 09:27Nylsvley Nature Reserve--Vogelfontein1
2021-03-02 16:13Nylsvley Nature Reserve1
2021-02-26 10:45Kruger NP--Punda Maria Camp2
2021-02-22 06:12Kruger NP--Bridge over Luvuvhu River
2021-02-21 06:11Kruger NP--S602
2021-02-21 07:14Kruger NP--Klopperfontein Loop/Dam1
2021-02-26 06:00Kruger NP--Sirheni Bushveld Camp2
2021-02-23 05:55Kruger NP--Nshawu Vlei
2021-02-26 06:58Manyeleti Game Reserve3
2021-02-11 05:13Singita Ebony Lodge1
2021-02-09 05:22Mala-Mala Game Reserve6
2021-02-06 21:06Kruger NP--Skukuza Camp1
2021-02-25 07:10Kruger NP--Leeupan
2021-03-02 11:31Kruger NP--Timfenheni Loop/S121
2021-02-13 09:00Chhatardi Lake2
2021-02-13 07:15Mokarsagar Wetland Complex1
2021-02-25 07:15Sasoi Dam7
2021-02-21 16:23Dhinchada Lake6
2021-02-26 11:15Wetland near Jamnagar Railway Station2
2021-02-28 14:12Lakhota Lake60
2021-02-28 07:30Rangmati Dam95
2021-02-26 17:55Vibhapar2
2021-02-12 08:30Ranjitsagar Dam2
2021-03-05 08:30Balachadi Beach2
2021-02-20 08:13Vadla Lake5
2021-03-07 07:25Nyari-2 Dam2
2021-02-14 08:30Baghi swamps1
2021-02-07 07:15Nyari-Khirasara Birding Corridor2
2021-02-28 07:07Garida Dam7
2021-02-23 07:00Khodiyar Dam23
2021-02-23 04:30Thordi Lake120
2021-02-21 16:30Thebi Dam160
2021-02-06 11:20Vadala Dam200
2021-02-21 11:32Vadla Dam( 22.916, 71.971)10
2021-02-20 08:54Khokhla Talav50
2021-02-21 07:35Nalsarovar Outskirts--Shahpur5
2021-03-07 08:00Nalsarovar Bird Sanctuary6
2021-02-16 10:31Nikol Bandhara5
2021-02-06 21:51Nalsarovar--Boating Point2
2021-02-27 16:01Nalsarovar--Flamingo Sankul4
2021-02-20 13:37Bhogawo River near Fedara2
2021-02-07 16:39Kumbharwada wetland20
2021-02-16 16:54Krishnakunj Lake20
2021-02-08 15:20Avaniya Lake12
2021-03-06 08:00Thol Bird Sanctuary5
2021-02-09 15:01Dabhla Panjarapole10
2021-02-14 14:24Rancharda Lake10
2021-02-28 10:00Gatehara Lake2
2021-03-03 10:00Sabarmati Riverfront--Vasna Barage B130
2021-02-21 15:33The Serenity Library5
2021-02-14 15:30Juni Akhol2
2021-03-01 18:23Limbasi-Vastana Rd35
2021-02-14 07:42Narmada Canal, Karai2
2021-02-13 15:20Sant Sarovar103
2021-02-12 14:28Punit Van3
2021-02-28 15:13Aranya Udhyan2
2021-03-01 17:04Narda Wetland12
2021-03-01 17:14Pariej Lake23
2021-03-07 08:04Pariyej Lake extantion7
2021-02-16 07:45Gaviyer Lake2
2021-02-12 08:09Abrama Talav, Navsari (20.861, 72.897)20
2021-03-06 01:12Polo Forest2
2021-02-18 07:45GSRTC ST Depot18
2021-02-13 08:07Lokhandwala Lake1
2021-02-19 17:05Rajavali Marshes, Vasai15
2021-02-18 10:35Timbi Lake25
2021-02-07 08:00Bhopar grasslands, Thane1
2021-02-23 15:37Vadatalav Lake
2021-02-07 07:56Menar Lake20
2021-02-28 07:24Nandur Madhyameshwar Bird Sanctuary2
2021-03-03 13:28Jhal Thikriwala4
2021-03-03 12:44Jhal Thikriwala- Punjab2
2021-02-13 06:40Sambhar Lake3
2021-02-06 10:57Raiwasa Lake & surroundings3
2021-03-05 08:20Raitollem Lake
2021-02-13 10:12Ranjit Sagar Dam8
2021-02-12 09:00Balya Maruti Temple lake10
2021-02-13 14:49Mattewara Forest1
2021-03-08 07:30Lake Man Sagar, Jaipur46
2021-02-07 07:30Kishanpura (Machal) Wetland, Indore17
2021-02-07 08:07machal12
2021-02-24 10:30Lake View2
2021-02-28 09:00Sirpur Tank3
2021-03-02 09:00Sirpur Lake5
2021-02-27 07:15Baroda Daulat Village Pond6
2021-02-25 14:06Mote Majra5
2021-02-28 10:14MoteMajra Lake4
2021-02-14 08:14Hatnur Dam (IBA)6
2021-02-28 07:30Sukhna Lake Reserve Forest1
2021-02-21 12:22Banas River2
2021-02-21 16:00Mandothi
2021-02-25 15:11Banas River10
2021-02-27 08:00Budhera WTP, Gurgaon1
2021-03-06 19:34Indian Institute of Technology (IIT), Delhi7
2021-02-24 07:40Okhla Bird Sanctuary2
2021-02-09 06:45Kunnumkai1
2021-02-10 06:45Kattampally1
2021-02-22 15:14Asan Conservation Reserve2
2021-03-02 12:39Bharatpur--Keoladeo Ghana NP3
2021-02-27 07:30Dhanauri Wetlands -- Dhanauri Kalan East50
2021-02-21 15:11Dhanauri Wetlands20
2021-03-07 10:35Ankasamudra Bird Sanctuary ಅಂಕಸಮುದ್ರ ಪಕ್ಷಿಧಾಮ1
2021-03-03 22:27Bhoj Wetland1
2021-02-14 09:28Van Vihar NP1
2021-02-07 07:16Kaliyasot Dam20
2021-03-07 11:41Wildlife Institute of India Campus1
2021-02-22 10:32Wildlife Institute of India Campus--Nature Trail1
2021-02-28 07:43Soor Sarovar Bird Sanctuary15
2021-02-21 10:00Haiderpur Wetlands and Bijnor Barrage3
2021-02-28 10:00Yamuna River near Taj13
2021-02-27 08:55Sheikha Jheel (IBA IN-UP-21)6
2021-03-07 07:55Nagla Kanch , Rati Ka Nagla Wetland1
2021-03-02 09:26Tawa Bridge (NH 22)2
2021-03-03 10:02Satpura Tiger Reserve -- Sakot Forest Camp10
2021-03-03 07:49Satpura Tiger Reserve -- Adi Denwa Patrolling Camp2
2021-03-03 16:52Satpura Tiger Reserve (Overall)1
2021-03-07 12:48Denwa Backwater Escape (Pugdundee Resorts) -- Satpuras2
2021-03-08 07:54Denwa River Backwaters, Madhai2
2021-03-05 09:23Satpura TR--Madai10
2021-02-20 08:45National Chambal Sanctuary -- Jaitpur10
2021-02-21 07:22National Chambal Sanctuary -- Nadgawan2
2021-02-21 06:45Karhal Bypass Road, Karhal1
2021-02-14 09:00Anna Sagar Lake1
2021-02-26 07:00Manjeera Wildlife Sanctuary7
2021-02-28 06:30Pocharam Wildlife Sanctuary5
2021-03-07 06:20Nehru Zoological Park2
2021-02-15 17:56Melapattam Karisalkulam2
2021-02-19 07:00United-21 Tiger Camp Resort, Bhamdeli, Moharli3
2021-03-03 06:40Tadoba -- Erai Dam2
2021-02-07 07:24Rani Durgawati WLS11
2021-02-21 14:30Padariya3
2021-02-15 11:32Palamadai/Rajavallipuram6
2021-02-09 15:30Sivandipatti Lake & Grassland10
2021-02-17 16:37Koonthakulam Bird Sanctuary7
2021-02-21 12:26Melakulam-- Karungulam (கருங்குளம்)9
2021-02-14 09:55Sawarla Lake2
2021-02-13 13:00Chattarpur, Jabalpur50
2021-02-16 07:00Ghodaghodi Lake and Important Bird Area8
2021-02-21 07:30Hulas Khera Archaeological Excavation Site5
2021-02-12 10:35Kattoor Lake -Thiruvallur (காட்டூர் ஏரி - திருவள்ளூர்)1
2021-03-02 16:16Sholinganallur/Perumbakkam Marshlands1
2021-02-13 06:58Kopra Dam2
2021-02-25 06:44Matara--Kirala Kele Sanctuary2
2021-02-07 13:06Rukka Dam, Ranchi, Jharkhand, India2
2021-02-23 10:04Gogabil Pakshi Vihar (IBA) -- Baghar Bil1
2021-02-15 15:45Gogabil Pakshi Vihar (IBA) -- Jangli Tal4
2021-02-20 11:00Ballavpur WLS Jheel 33
2021-02-20 10:00Ballavpur WLS Jheel 22
2021-02-09 15:57Santragachi Jheel (Lake)1