Early this March, a group of four Black Vultures congregated on our next door neighbor’s lawn, at the shore of our lake. They were tearing apart the dead body of a Muscovy Duck. Later in the day I took a look at the carcass, now little more than a bunch af feathers and cleanly picked bones. I did not think much of it until a few days later, when I noticed that tough old “Pato El Presidente,” the alpha drake who ruled our section of the lake’s shore, was missing. See previous blog entry about him here.
During the next couple of weeks there were many skirmishes between rival drakes, with two particular ones, a pure white specimen whom I named Whitey, and Whitewing (pictured, previously an incessant rival of El Presidente), appearing to have the upper hand. Discord among the ducks continued well into April. Whitey appeared to emerge as the new boss of our piece of the lake. Previously, Whitey’s territory centered on a home diagonally across from us, where the owner regularly fed the ducks and pigeons. This must be the most prized territory on the lake, so perhaps Whitey was displaced to a lower position in the Muscovy heirarchy.
This spring, the third we have spent here in South Florida, we have so far seen no Muscovy Duck chicks on our 10 acre lake. Usually, by now there would be between 3-10 broods in various stages of growth. During March and April I found four nests on ours and neighboring properties with eggs that failed to hatch. One nest just off our patio contained 14 eggs and the hen incubated them for well over a month before abandoning them, all intact.Could this be due to the instability of the social order that was caused by the loss of El Presidente?
I wonder whether this is unique to our lake, or has anyone else noticed it? Could the nesting failure be related to the record drought conditions that have brought our lake level down by almost three feet? With the low rainfall, is it possible that the pesticides from residential lawns, or the herbicides that the South Broward Drainage District regularly sprays along the lake margin, might have become more concentrated and thus have an unexpected anti-fertility effect?
Are other local species experiencing similar problems? True, I am not concerned about the Muscovy population, but want to be reassured that this is not an indicator of any larger problem. After all, the web of life encompasses all of us.
May 29th, 2007 at 6:07 am Ken: By the luck of the draw, your blog (and this post in particular) is being featured today in the Random Gleanings series of my blog, Birds Etcetera. Congratulations!
June 6th, 2007 at 10:16 am Yesterday, in the next door neighbor’s yard, we saw this year’s first set of Muscovy ducklings, 13 in all. This morning they were down to seven, about par for the course. We have several large soft-shelled turtles that may account for some of the missing. Ken
July 20th, 2007 at 6:04 pm We have had Muscovy ducks for many years here in ND. This year we have female ducks carrying and chasing new hatched ducklings. The ones they were carrying were mangled about the head. Do female Muscovys KILL babies ??? [Follow-up e-mail from Judiel: Thank you so much for emailing back. This is something that has never happened before and we have had Muscovies for MANY years. I went to both water holes yesterday..and we have NO baby ducks. Normally this time of the year we probably have 75/100. We have been snatching up the babies as they hatch and putting them in pens to save their lives. Horrible. We have only seen hens with babies in their mouth and the babies have flattened heads and are dead. Is this a horrible trend ? …or will it not happen again. I can’t imagine what is happening. ..and we are in ND. Have you heard of other places with this problem ? thanks, Judie]
July 21st, 2007 at 7:32 am Judie, thank you for posting. I did witness the carnage only once, when both drakes and hens participated in killing about a dozen newly hatched ducklings. The adults took the babies up and shook them and certainly drew a lot of blood. Others have noted that drakes were particularly aggressive. Other readers have seen Muscovy and Mallard drakes kill ducklings. See earlier blogs and comments that do describe this behavior in other places, and some ideas as to what may cause it. Crowding and competition for food and territory may be factors.
MORE KILLER DUCKS <http://blog.rosyfinch.com/?p=47>
PURPOSEFUL INFANTICIDE <http://blog.rosyfinch.com/?p=45>