How could this carnivorous plant "eat" a rat?

[astro]

Per this article Giant Rat-Eating Plant Discovered in the Philippines which references this plant.

Even at it’s largest it’s about the size of a 2 liter beer pitcher. Most rats can swim. Even if one fell in, a small rat could easily (IMO) just scramble over the top and out of that “pitcher”?

[beowulff]

Most pitcher plants have backwards-sloping hairs lining the throat of the pitcher. This prevents their prey from climbing out…

[RaftPeople]

If you read that article you linked you will find your answer.

[Chronos]

I don’t see an answer in either of the linked articles. Care to share?

And it’s a good thing this rat-eating plant lives in the Philippines, not Sumatra.

[Fake_Tales_of_San_Francisco]

@Chronos

I don’t see an answer in either of the linked articles. Care to share?

The wikipedia article says the lower fluid inside the pitchers is viscous. Could the rats get stuck in that, unable to swim?

[RaftPeople]

@Chronos

I don’t see an answer in either of the linked articles. Care to share?

And it’s a good thing this rat-eating plant lives in the Philippines, not Sumatra.

"…The plant then closes its tube, trapping the prey inside. "

[Colibri]

@RaftPeople

"…The plant then closes its tube, trapping the prey inside. "

I think that’s probably an error on the part of the author of the article. Other references indicate that Nepenthes pitcher plants do not close their lids, although an early naturalist alleged that they do. The photos also show the lid, even if it moved, is too small to close the opening.

The upper part of the interior of the “pitcher” is waxy, as the lip of the opening overhangs a bit. Once a rat is inside, it will have a hard time scrambling out, and will eventually drown.

[Koxinga]

I don’t see anything in the original BBC article indicating they had actually found evidence of rats being consumed, just that it was big enough to trap a rat. Is that only hypothetical?

[Really_Not_All_That_Bright]

Courtesy of the International Carnivorous Plant Society:

Nepenthes pitchers usually capture small arthropods. Ones near the ground tend to capture crawling creatures while those higher in the air tend to capture more winged insects (although there is plenty of overlap). Sometimes small vertebrate animals are captured, too. Nepenthes rajah is sometimes cited as capturing little frogs. Did you know that the last thing in a frog to be digested is the skin of its hands? Look in a pitcher of Nepenthes rajah and you can learn about how many frogs it has been eating by looking at the little gloves floating in the juices!

Occasionally, yes, very occasionally larger animals such as very small rodents are captured. But this is rare, and does not really reflect upon the normal course of things. You probably eat the occasional cockroach without knowing about it, but I doubt you would consider them part of your regular diet. (Or would you? Eeek!)

[Colibri]

@Koxinga

I don’t see anything in the original BBC article indicating they had actually found evidence of rats being consumed, just that it was big enough to trap a rat. Is that only hypothetical?

I think so, but it is based on its similarity in size to Nepenthes rajah, which is known to trap small vertebrates:

N. rajah is known to occasionally trap vertebrates and even small mammals. Drowned rats have been observed in the pitchers of N. rajah.[6] It is one of only two Nepenthes species documented as having caught mammalian prey in the wild, the other being N. rafflesiana. N. rajah is also known to occasionally trap other small vertebrates, including frogs, lizards and even birds, although these cases probably involve sick animals and certainly do not represent the norm. Insects, and particularly ants, comprise the majority of prey in both aerial and terrestrial pitchers.

[RaftPeople]

http://conservationreport.com/2009/08/12/new-species-of-tropical-pitcher-plant-discovered/

Middle video section of this page shows video’s 1-15, 1st shows a mouse going into a pitcher plant (I assume not the exact same plant, but looks very similar).

[enigmatic]

Yeah, the original BBC article does not state that the pitcher closes. That statement seems to be a result of the second author misinterpreting a sentence referring to Venus fly traps. Pretty sloppy journalism there.

[smiling_bandit]

Even at that size, note that they say it can kill rodents. It’s probably not talking specifically about a full-grown brown rat, which would like claw and chew its way out.

[dracoi]

@smiling_bandit

Even at that size, note that they say it can kill rodents. It’s probably not talking specifically about a full-grown brown rat, which would like claw and chew its way out.

A full-grown rat would probably be safe.

Of course, a rat that was drowning in a full pitcher plant might not have the intelligence to realize it could chew through the side of the plant. Rats are more likely to drown in ponds or streams where chewing through the side isn’t an option, and it requires some capacity for logic to realize that chewing through the side would work in this case. Instead, the rat might focus on trying to climb up the sides of the pitcher, which are designed to make that difficult.