'We have to make it stronger
this pirate ship for three
the last one it sank
somewhere out at sea.
As Terry-Tu flew up high in the sky
and Hopper swam fast, heading for the shore
Jan de Bouff was found next day
floating on a door." they chanted
as they worked.

- I don't know if you are aware or not, but you open the speech with ' but end it with " which I think you meant to open it with " also.
- Maybe this is just how I was reading it, but I feel there would be benefit to the poem if you added a comma on this second line after three?

With his strong red beak
he had it loose in no time
and...as Jan de Bouff
tied it to the mast
they were finally ready
to pull anchor and
set off on there adventure.

- there should be their, on this last line.

"Oh Arr! Oh Arr! ...we'll sail the seven seas
scallywags and scoundrels, we are pirates three
We'll steal your gold coins, won't listen to yar pleas
We'll fill our treasure chest and still be home for tea!"

- I know this is speech, but I would still punctuate it with commas where the reader should break, I feel it has a really good flow and rhyme scheme to it, and the commas would help structure this flow. So at the end of each line really since the new line is another little statement in the song/chant.

As for the poem, I still love the adventure you take us on! But more so the language use of the pirate. I really like how you turn him into a very greedy and selfish pirate which is typical, but it works really well. The cheek of the other characters still shine through here. I already began to imagine their ship, the skull and cross-bone sail, and I did laugh at the supply of alcohol, I thought of them getting arrested out at sea for drunk driven haha.

Still enjoying these stories, thanks! x