Scientists concerned over high mortality of St Lawrence belugas

Scientists at a marine research centre in Tadoussac Quebec, are concerned about a dramatic increase in beluga mortality in the St Lawrence estuary.

Researchers at the “Groupe de recherche et d’education sur les mammiferes marins” (GREMM) which studies marine mammals, says data going back to the 1980’s shows that typically 3 or fewer dead beluga calves are found each summer.

Robert Michaud, GREMM scientific director, says since 2005 there have been more dead calves found and “ a new kind of mortality in females, – a lot of females are dying in neonatality situations, either just before, during, or after giving birth”.

In 2008, scientists found eight dead calves, and 11 in 2010, and last year, some 17 calves were found washed up or floating in the river.

There is an isolated population of  belugas around Tadoussac at the mouth of the Saguenay river.  This is where the fresh water of the St Lawrence and Saguenay rivers has already begun mixing with the oceanic salt water of the estuary.

These are the southernmost belugas in the world and were almost hunted out of existence by the 1950’s.  Protected since the 1970’s, the last census in 2005 estimated the population to be about 1000 of the whales.

Marine mammal researcher Lynn Morrisette, noted that in 2012 at the same latitude in Argentina , scientists there noted a doubling of whale deaths, also unexplained.

The researchers so far have no explanation for the mysterious increase in beluga deaths. Robert Michaud says that federal budget cuts have hampered research and analysis abilities to find the cause or causes.

Meanwhile, further down the St Lawrence, residents in the Gaspe region reported a sharp increase in the deaths of gannets.

Scientists have speculated that the small fish the birds feed on have gone deeper as the waters above have become warmer with climate change.

 GREMM (in French only)