Where's the other half?

I just read this article from the LA Times. Emphasis added:

For months, the rafts that ferry Disneyland guests across the waterway to Tom Sawyer Island have been idle. No children have explored the island's caves, scaled its climbing rocks or run across its bridges.

But the island won't be lonely much longer. Park employees will refill the Rivers of America, drained in January for maintenance, this week. The draining took almost a week, at the end of which this question was answered: What do you find at the bottom of an amusement park basin after seven years?

The answer: a computer tower, hundreds of cellphones, countless pacifiers and half a canoe, said Disneyland Resort spokesman John McClintock.

While it was empty, employees repainted, replaced and cleaned park features along the shore, basin and island. In the past, the drained water went into the ocean. To minimize the environmental impact this time, the park collaborated with the Orange County Water District and drained the water through a valve, purified it and added it to the county's reserve.

First of all, I think it's really cool that the millions of gallons of water at Disneyland actually got used instead of just washed away. I remember thinking, as a kid, that there was so much water at Disneyland that they could provide water for all of Anaheim for at least a day or two. There's probably not THAT much water there, but there's a lot.

And, yes, why did they find a computer tower in the bottom of the river? Good question.

But...here's what I want to know: how did they only find one half of a canoe? WHERE'S THE OTHER HALF???!!!?

How does someone lose HALF a canoe? Did someone STEAL the other half? And if so, what good is half a canoe to them? Did the other half of the canoe DISINTEGRATE? And if so, what is in that water that causes canoes to disintegrate? Was someone paddling in the canoe, and it broke in half, and after the first half went down, some park employee was like SAVE THE OTHER HALF! And if so, where is the FIRST half?

What's the half-life of a canoe anyway?