Wyatt Fournier
As I
mentioned in my first post, every year we observe something a little different
out here in the Gulf of Alaska. For the
past few weeks we have been catching more Young Of the Year (YOY) Walleye pollock
than on any previous survey. Almost
every time we haul the net back there are pollock, both at the surface and at
depths up to 100 meters and deeper. At
the same time there has been a relatively low abundance of juvenile rockfish and
arrowtooth flounder and no signs of Pacific cod or sablefish.
Our local
climate has also been different this year as we experienced a prolonged cold
spring that kept the snow pack in the mountains and the ocean temps cool. Then in June, the state of Alaska had a mini-heat
wave that melted snow and had locals peeling off clothing. The cold spring kept the streams and rivers
cool and may have delayed the development of smolting salmon and would explain
why we have caught very few pink and chum salmon on this survey despite the
warm weather this month.
These
temperature swings that we enjoy here on land are also taking place in the
ocean and can influence reproduction timing and survival of marine fish. It is possible that the ocean conditions and
prey availability this spring were optimal for juvenile pollock survival but
not as beneficial for other species. Our
physical and biological oceanography observations conducted on this survey will
help us answer some of these unknowns as we investigate the mechanisms between
climate variability and juvenile marine fish survival.


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