Dorothy breeds again!: duck-related matters leading to reduced posting

Well, Dorothy, who clearly wanted to have her own family after her entire brood was purloined by Honey, produced seven ducklings yesterday. This second batch leaped down from the third-floor window in Erman hall next to the pond, coming down while I was feeding Honey’s brood across the pond. The time was about 8:45 a.m. As always, the mom flew first to the ground and quacked, and the peeping babies jumped down one by one. One even hit the ground and bounced into the water, apparently without harm. I was surprised by her late breeding, but of course this is her second effort. Our final brood last year appeared at about the same time.

I am not going to remove the babies from Dorothy because, sitting by the pond most of the day yesterday, I saw that there were almost no negative interactions between Honey’s nearly-grown brood and Dorothy’s new one.  And I feel that Dorothy needs a chance to raise her young on the pond so long as they’re not endangered. So far, so good, though it’s only 24 hours since they jumped.

Here’s Dorothy with her seven babies:

Another view. She’s a proud mom. She sat on eggs for a total of two months, one month per brood, and I want her to keep this one (there’s no chance Honey will steal them; they’re way too young.

One of Dorothy’s babies, just a day old at most.  The protrusion at the end of its beak is the egg tooth, a feature that the duckling uses to peck its way out of the egg. I don’t think it’s homologous to the reptilian tooth, as it’s made of calcium carbonate. It’s also shed about a day after the duck hatches.  Here’s the Wikipedia description:

A mother bird delivers her young encased in an eggshell; an external protective covering consisting of calcium carbonate (CaCO3). The shell protects the chick until it is ready to survive in the outside world. The chick breaks open the shell when it is strong enough and ready. Since the beak and the claws of the bird are not fully developed and cannot penetrate the eggshell, the “egg tooth” is the unusual structure that helps the bird break through the shell. It is only found in emerging chicks and lost soon after hatching, after it is used to penetrate the hard shell that once protected the embryo..

Seeing if something is nomm-able.  The babies don’t really eat for 24 hours after jumping, but I’m trying to feed Dorothy and give her babies a bit of duckling chow. To do this, they have to be well apart from Honey’s brood, just like last year when we were feeding three broods at once. If one gets fed and not the others till later, the others tend to come over for some chow. I must keep Dorothy’s brood separated from Honey’s. Dorothy is good at driving off Honey’s ducklings, but Honey is bit more persistent though, unaccountably, she doesn’t seem to want to attack Dorothy or her brood.

But was it really Dorothy who re-nested? Yes it was. Here’s her bill pattern 6 weeks ago with the distinct dot under her nostril (ergo her name).

Her bill had darkened up a bit since then (as has Honey’s), but it still shows the dot pattern. Dorothy looks a bit peaked, probably from not eating much while incubating. Also, there seems to be a dent in her head, which could be feathers removed when she was being pecked during her previous breeding attempt.

Contrast the photo below with the one above. Dorothy has a huge tuft of feathers pulled out of her head (probably from “forced copulation”, i.e., duck rape) and has lost a ton of weight. Hens often lose 30-35% of their body weight during the one-month incubation period, and Dorothy incubated twice. I’m trying to feed her up with good duck chow and mealworms now.

When the babies jumped, I ran upstairs to put on my pond clothes in case I had to go into the drink to rescue the babies were they attacked. While I was dressing, my colleague Jean Greenberg took three videos of the babies right after they jumped but before they started swimming. In this first one, Dorothy has lured two babies into the water, but five of them, peeping, remain on the bank.

Here there’s one straggler left on the bank, frantically making the “don’t forget me!” peep. Dorothy finds it and quacks until it runs to the water.

And the brood, all together and staying close to mom, gets ready to start exploring their world.

A short while later, the brood went into the channel and began exploring. Dorothy has been eating, and the duckling pecking at food and other detritus, so all is well.

What worries me is not so much the interactions between the broods, but the fact that people keep disturbing the brood when Dorothy is sitting on them. If you’re reading this, please give all lone hens, especially on the bank of the pond, a wide berth!

More reports will follow. In the meantime, I ask your indulgence because the lives of this brood is a higher priority than posting here, and I want to get them started on the right webbed foot. Posting will necessarily be light, but bear with me and please don’t stop following the site. Thanks!

 

44 thoughts on “Dorothy breeds again!: duck-related matters leading to reduced posting

  1. Say, Mister Deejay, do we have a tune we can dedicate to our gal Dorothy?

    Why, yes, yes we do:

    1. As rickflik says, probably a change in hormones. The instinct to protect hatchlings isn’t there any more.

      ***

      Congrats to Dot! An grandpa PCC!

      ***

      What I find most interesting is how fast Dorothy bred again. I’d heard of this sort of response in mammals, where as soon as the little ones are gone mom becomes biologically ready to breed again, but I had no idea birds had it too and I’m amazed at how fast the breeding instinct reasserted itself. We’re talking literal hours or at most a few days here.

  2. Could Honey be giving Dorothy and ducklings a wide berth because she feels guilty? Or perhaps after a month or two of raising 17 little ones, she’s had enough of little ones for a year at least. It’s never dull down on Botany Pond!

    1. I’d like to think that if ducks could feel guilt, there would be much less duck rape.

    1. Although it’s not going to help with my pondcam addiction, I’m glad to hear that Dorothy’s new brood is going to stay.

      By the way, I’ve been appreciative of the commentary on the various duck vocalizations.

  3. Possibly since her babies are nearly fully grown Honey doesn’t feel threatened by the new bunch.

    1. I’m not sure it was ever “threatened” given that she ducklingnapped and raised Dorothy’s ducklings, she didn’t kill them.

      Seems to me more that her instinct was just a broad ‘protect/guard the little ones’ without any distinction. As the ducklings grow, her instincts are to protect that cohort, but not necessarily others.

  4. Thank your colleague for the videos. She has been a great asset in your duck farming exercise.

  5. Well, this is terrific. I didn’t realize (I don’t know much about birds) that ducks could lay another clutch of eggs like that. Good for Dorothy!

  6. I have seen ducks here with little ones as late as September. Maybe due to losing early ducklings such as this.

  7. I have to say that before becoming “acquainted” with Honey and Dorothy I had no idea of the work and time involved in ensuring the safety of ducklings.

    1. I live beside a creek in Kelowna BC and have observed the ducky domain for many years. The attrition rate for the ducklings is very high. I have often seen a group of 10-12 ducklings reduced to half that in a week. The creek here can flow very fast in the spring and I think many get carried away. Maybe predators is another reason – now I wonder how often other moms are stealing them. I have seen calm efficiency with, most likely, the experienced mothers and the obvious upset and chaos among some others. I was sad to see how mean one mom could be to other mother’s ducklings. It can al be a real soap opera.

      I am greatly appreciating Jerry’s hard work, dedication and recording the events on Botany Pond.

        1. Perhaps just confusion over whose chicks are whose. It’s not like they come with labels on them. Evolution has not seen fit to correct this behavior as it isn’t so bad for the species. After all, Dorothy went and got a new family so it actually might be encouraged by evolution. (Yes, I know this is filled with anthropomorphic language.)

          1. I don’t see how the behavior can be encouraged by evolution because it does not favor the hen who steals the brood even if the victim hen does breed again. But I agree that perhaps the cost to the stealing hen is low because she doesn’t feed the ducklings, she just acts as a protector. The cost of that is about the same with seventeen ducklings as with seven, so there is no evolutionary pressure to weed the stealing behavior out. If costs of caring for ducklings were higher per duckling, I imagine the stealing behavior wouldn’t happen.

            1. I’m not sure there needs to be positive selection pressure for mother’s stealing other hens’ chicks. That may just be an incidental aspect of other traits that were selected for. Then, as long as there is no negative selection pressure against the incidental behavior it could persist.

              Or, another possibility, the behavior of mothers’ giving up their chicks to other hens may have been the behavior that was positively selected for. For example, just that behavior enabled Dorothy to produce 2 times in one season rather than just once and all the chicks were still cared for.

              1. If you can get another hen to raise your chicks, freeing you (free-er) to have another batch, that’s an evolutionary win. It sounds like Honey taking on the extra burden is a mistake, but with low enough cost (or frequency?) for evolution to ignore it.

              2. Yeah, seems plausible though it could of course be completely wrong.

                And it’s definitely not a species selection scenario since the individual exhibiting the trait, Dorothy, is the one that gains an advantage in passing on more of her genes.

              3. Well, no, I wasn’t confusing with brood parasitism. I was pulling semi-plausible ideas out of my butt. But yes, the one is rather similar to brood parasitism. I was suggesting that maybe the mother doesn’t need to be actively sneaking her offspring into another mother’s care, but that she merely needs to be more risk adverse than other mothers when it comes to these sorts of mother-mother fights.

            2. That makes sense; there is little cost to the hen. But the behavior could benefit the chicks. It may not be so much that Honey stole the chicks as the chicks abandoned Dorothy. One could imagine (and, really, that’s all this is) that there is an advantage to chicks survival if they can become members of another brood. If their mother is killed or they get lost, during that period in their lives, it might pay for them to be able to swap moms.

              Is this a common behavior among mallards, or is this perhaps an outlier, a the result of a series of coincidences?

            3. My thoughts exactly. The cost to the stealing hen must be low. There might even be benefits, such as indicating to future mates her prowess as a mother. Perhaps that’s a stretch but I thought it worth mentioning.

        2. It would make more sense if Dorothy is Honey’s daughter. Given that mothers will attack other ducklings, maybe they have some way of (in effect) detecting kin. ????

    1. I’ve read the interesting comments about Honey vs Dorothy and the cost of purloining another’s chicks. It wasn’t mentioned, but I would think there’s a cost to Dorothy having to starve for yet another brooding period and bringing her offspring into the world in the summer rather than spring. I’m inclined to think that Jerry’s heroic caring of mother and young, as well as the help of his duck farming team, might have some effect on duck behaviour on Botany Pond.

  8. My hypothesis, which is mine, is that a hen which steals newly hatched ducklings provides her own offspring with a big social group which easily rules the territory when the ducklings grow larger and are putting more pressure on the food resources in the territory.

    1. Do ducks really have that much social cohesion? AFAIK, there’s not much (any?) cooperation between ducklings or the ducks they grow into. Perhaps they don’t fight within their group but it’s not like Honey now has 17 protectors instead of, say, 10. On the other hand, she’s got more mouths to feed from one pond. Notwithstanding the fact that this particular pond has a benefactor with a virtually unlimited quantity of duck feed, Honey has reduced the resources available for her real offspring and herself.

    2. I just read this thread quickly, but one hypothesis is the “dilution theory”: if a predator picks off just one of your brood, and you’ve doubled it by purloining unrelated offspring, the chance that your genes are removed from the gene pool is halved. There could thus be a selective advantage to kidnapping. Of course this has to outweigh any costs of tending a larger brood.

      1. That theory makes sense to me. I think. You often see mallards with very large broods that are unlikely to be all the hen’s own. Now if only the hen’s own ducklings could be kept closer to her than the cannon fodder…

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