I can observe the rafts of Aythyas in the lake here by Lansing Station Rd. from the railroad track & cliff top areas overlooking the water. I am 18-20 feet above them and that seems not to disturb them so they stay fairly close to shore. Where they often dive the water is about 9-13 feet deep this time of year. (The NYS Canal Corporation lowers Cayuga lake about 3 feet in winter). The water a fair ways out from shore down by Stewart Park in summer is only 12 feet deep.
I can see the birds here surface with pieces of plant material in their bills. Once while attempting to watch the Tufted Duck Sunday, i saw another duck with a lumpy thing in its beak, probably a mussel or little crayfish. Due to over a decade of Zebra mussel growth in the lake, the water has become quite clear. This allows a lot of weed growth, so presumably this provides a lot of food for the ducks. In summer my friend who lives on the south shallow end of the lake has massive amounts of lake weeds to contend with. Here weeds grow almost to the surface by August at depths of 4 to 12 feet. If they eat Zebra Mussels there are zillions of those in the shallow zones 4-12 feet deep. Sent from my iPhone Donna Scott On Jan 25, 2015, at 8:47 PM, Benjamin Freeman <[email protected]> wrote: > Hello all, > > Alexa and I had the good fortune to watch the Tufted Duck for an hour or so > on Saturday morning. It was diving actively the entire time, which made it > tough to find (and difficult to show to others in the scope). Which got me > thinking: What are the various Aythya eating? The Tufted Duck was clearly > associating with scaup on Saturday that were actively feeding. Also present > were several big flocks of Redhead (all loafing around), and a decently big > group of Canvasback (also loafing). > > A quick search informs me that Aythya eat gastropods, mussels and aquatic > vegetation among other things, and that the relative proportion of animal > food in their diet varies seasonally. > > Does anyone know what they are eating in Cayuga in winter? Must be a fair bit > of food to support so many birds for several months... > > Do different species of Aythya eat different things? > > Can you tell when Aythya are eating gastropods/molluscs/animal food vs plants > based on their diving behavior? > > Looking forward to learning what these ducks are up to, > > Ben > > -- > Benjamin Freeman > Ph.D. candidate > Department of Ecology and Evolutionary Biology > Cornell University > Ithaca, NY, USA > benjamingfreeman.com > > -- > Cayugabirds-L List Info: > Welcome and Basics > Rules and Information > Subscribe, Configuration and Leave > Archives: > The Mail Archive > Surfbirds > BirdingOnThe.Net > Please submit your observations to eBird! > -- -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/[email protected]/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
