The P.E.I. government is still investigating what caused a major fish kill on the Montrose River last week.
More than 2,000 dead brook trout were found over a 4.5-kilometre stretch of river after the fish kill was reported Friday.
For now the waters remain off limits, and according to provincial officials the popular fishing spot at Marchbanks Pond as well as the entire river may be closed to angling for two to three years.
Provincial freshwater fisheries biologist Roseanne MacFarlane said it appeared the fish had been dead for a couple of days.
This is the third fish kill on the Montrose River since 2010. The other two were found to be related to pesticide runoff from farm fields.
"At this point there's no specific cause determined," MacFarlane told Island Morning host Mitch Cormier.
"There are some similarities to the previous two, in terms of timing. It followed heavy rainfall earlier in the week. The fish all died rather suddenly."
The temperature and oxygen content of the stream were normal, she said.
Raccoon tracks located in the area show where animals have been eating the remains.
With the help of the local watershed management group the cleanup of the stream was finished on Saturday.
"Disappointed, discouraged, but we can't give up," said John Lane, co-ordinator of the Cascumpec Bay Watershed Association.
Lane said the group does not usually re-stock this river with fish from hatcheries because the natural population is typically so healthy.
In this case, he said they will be taking inventory to see if re-stocking, combined with closing the waters to sport fishing, can help the river recover.
MacFarlane said the amount of time between the kill and its discovery will make determining the cause harder.
"Certainly does make it more difficult when it's been a few days since the fish had died. Whatever might have been in the water in that point is long gone, as well, and with the decomposition of the fish it's very difficult to find anything," MacFarlane said.
Multiple fish kills in the same river are always a concern, said MacFarlane, but she expects the Montrose will eventually recover again.
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