Fatal Enigma

It has come in the legends that the death of Homer, the great ancient Greek epic poet was the consequence of the suffering, he endured for not being able to make sense of an enigma.
Here is the fatal enigma, (but, please don't die if you fail to answer; it realy doesn't worth it, for those who know the answer there is no perilous risk):

On the day preceding his death, Homer was sitting on a rock watching the fishermen rowing back to their village; when they approached, he saluted them, and asked about the outcome of their labour; the youngest of them all saluted back and said:'those, we could catch, we left them over the place, and those we couldn't catch, we carry them home.' What did he mean?