Tetrapod Zoology

We all know that many birds feed their young. Nowadays, many of us are also familiar with the idea that hadrosaurs and other dinosaurs might also have fed their young. Far less well known is the possibility that crocodilians may do this too, at least sometimes. As with those fruit-eating alligators, I have John Brueggen of the St. Augustine Alligator Farm Zoological Park to thank for the video you see here (and thanks, again, to Tim Isles for bringing this subject to my attention in the first place).

In the video shown here, a female Siamese crocodile Crocodylus siamensis allows her babies to eat meat literally from her mouth.

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As John described in a longer article (here), what appears to be feeding behaviour has been reported in other species, including the American alligator Alligator mississippiensis, Orinoco croc C. intermedius and Broad-snouted caiman Caiman latirostris. It has also been seen more than once among the Siamese crocs at St. Augustine. Furthermore, the behaviour has been filmed in other species (namely the Chinese alligator A. sinensis).

Obviously, members of these species do not practise feeding behaviour on a regular basis (otherwise it would have been commonly observed). So, do they do it only on very rare occasions? Or is it that this feeding is not deliberate at all, but merely opportunistic on the part of the babies? For now, it remains yet another of those neat and potentially significant bits of behaviour where more data and more observations are needed.

Comments

#1 Richard Simons
November 8, 2008

Alternatively, could it be that it is just a few individuals that feed their young?
#2 Tilsim
November 8, 2008

Don’t some crocodilians guard their clutch, and later carry the hatchlings to the water? After you develop post-laying protection of the eggs, it would make sense to help the young after hatching. Not sure if all these behaviours occur in the same species though.

But well… maybe the young are just allowed to nibble until the chunk is small enough to be swallowed.
#3 David Marjanovi?
November 8, 2008

Or is it that this feeding is not deliberate at all, but merely opportunistic on the part of the babies?

Would surprise me. In the video, the mother just lies there as if glued to the ground, but her eyes are open.
#4 The Ridger
November 8, 2008

Possibly opportunistic in that mom doesn’t mind if they eat it, but wouldn’t think to feed them?
#5 Vladimir Socha
November 8, 2008

Why would it be impossible? I think we still have to learn much about these amazing animals…
#6 John H
November 8, 2008

I’ve seen the Siamese crocs feed the young at St Aug; they smeared dead nutria on the bank of their pool. And the cool thing was that male and female were involved in this and other parental care. Blew my mind!
#7 David Marjanovi?
November 8, 2008

Possibly opportunistic in that mom doesn’t mind if they eat it, but wouldn’t think to feed them?

Do crocodiles normally lie around motionless with food hanging out of their mouth? :-/
#8 Jose
November 8, 2008

I think the title should be �Do crocodilians suffer from narcolepsy?�
#9 Mark
November 8, 2008

Perhaps the answer lies in the fact that slabs of meat, rather than whole animals, are being offered. The article you cited mentions that in none of the documented instances was a near-complete corpse involved. Not being a zoologist (I’m going for a degree in Geology), my opinion may not be very well-qualified. However, here’s my layman’s idea: maybe it’s being done to encourage youngsters to go after carrion. With most carnivorous reptiles, lack of movement is a fairly large deterrant as far as prey items go. This could help stimulate the youngsters to become more opportunisic with regards to diet.
#10 Dorothy
November 9, 2008

great video thanks
#11 Robert
November 9, 2008

That was fascinating. The Adult could clearly have swallowed the meat at any time, but chose not to do so.

Clearly, as has been noted, more observation is needed before it can be said that this is specific care for the young.

My immediate reaction? – yes, she was feeding them.
#12 Jerzy
November 9, 2008

Video looks suggestive for a layman. But captive crocodiles and turtles, when satiated or almost satiated, often fall motionless with bits of food in their mouths. Other individuals can then try to nib it.

Feeding young contradicts several features of croc biology: female is supposed not to feed during rearing brood, and crocs are supposed to be polygamous with female defending brood from all other individuals. Maybe these generalizations don’t always hold. But I would want similar observation(s) from one of well-observed populations of wild crocs.
#13 Adam Britton
November 15, 2008

I think a lot of crocodilian behaviour has been misunderstood and misinterpreted, not to mention ignored, over the last few decades. This seems to stem from a generally dismissive attitude towards their presumed abilities as reptiles. I am reminded of the general contempt which greeted the first scientific reports that crocodilians showed parental care, opened the nest, transported the hatchlings down to the water, and protected them from predators for several weeks or months. Perhaps we don’t hear about this behaviour more often because people are simply not looking for it. There are, of course, a number of potential explanations for this behaviour, everything from opportunism to stress, but none of them are completely satisfactory.
#14 David Marjanovi?
November 16, 2008

This seems to stem from a generally dismissive attitude towards their presumed abilities as reptiles.

Ceterum censeo nomen “Reptilia” esse delendum.

We should really get rid of this name. It only seems to lead to misunderstandings.