p.1 #1 · Galapagos Islands- Masked boobies and eggs
Like most hunting/fishing birds, both parents are involved in raising their babies.
Because these masked booby adults all looked alike to me, I was not sure which gender was attending the nests.
Even though I'm a city boy, however, I'm pretty sure which gender actually lays the eggs .
Two different nest sites:
p.1 #3 · Galapagos Islands- Masked boobies and eggs
Those are pretty rudimentary nests Charlie. I heard a story about a long-lived albatross today (different species though). The guy was saying that their eggs take a lot longer to incubate than most birds. The one in the narrative had laid between 30 & 35 eggs, and was already 5 or so when banded. Total age was over 50 and estimated mileage on the her was very high (equivalent to 6 trips to the moon and back). Not bad for a bird.
p.1 #5 · Galapagos Islands- Masked boobies and eggs
Thanks Tam, Ken and...uh... you too Ron, I guess .
Incubation is 45 days. This species barely make nests at all, so the first-born usually kicks the second-born out of the nest and it usually gets so little food that it dies. The second egg is just an "insurance" egg anyhow- so the species doesn't suffer from such siblicide.
Other boobies build better nests, and often two babies are raised successfully.
Charlie
p.1 #10 · Galapagos Islands- Masked boobies and eggs
See Charlie, paying attention in those high school biology classes really paid off. I would be hard pressed to call that a nest...more like a nesting area or more appropriately a piece of dirt with rocks...amazing how the eggs survive being out in the open like that. I guess there just aren't the same number of predators snapping them up.
Nice shots btw
Eric
p.1 #11 · Galapagos Islands- Masked boobies and eggs
Nice info. Charlie. It doesn't seem right to have just one young boobie somehow! I'm always amazed how different nests are between similar species. Don
p.1 #16 · Galapagos Islands- Masked boobies and eggs
Thank you Lil, kmunroe, Jude, Ashley, Eric, Don, Socrate, Conrad and David.
All the boobies are closely related to the gannets. And they are similarly sized.
A native species of hawk is about the only predator on the Galapagos, and they can take anything small- including fairly large iguanas. But the greatest danger to booby eggs and the very young is the heat from the sun- so they are always protected at the nest by one or the other of the parents.
Siblicide isn't uncommon. i.e. bald eagle newborns sometimes practice the procedure- depending on whether there's enough food. I've seen pics where the biggest baby is swallowing its sibling. Again- often the second egg is just an insurance - in case the first-born isn't healthy. When birds live long lives, over-production of babies is not critical to the survival of the species. Theoretically, each mating pair needs to raise two babies to reproduction age for the species to survive.
Charlie
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~Ron
