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Warming temperatures shift ranges of fish, ragweed

A couple of recent publications have noted that the ranges of fish and ragweed are expanding to the north under the influence of warming temperatures on land and in the ocean.

CBC News reported on a recent study that tracked the ranges of 802 commercially exploited fish species and noted that ” the fish are slowly moving toward the South and North poles at a rate of between 15 and 26 kilometres a decade. The effect is more pronounced in the Arctic, where warming is happening the quickest.”  You can read this story here.  They noted that invasive fish species are also expanding, which could cause competition with native fish.

In separate studies from the US and Great Britain, scientists found that the length of the pollen season for ragweed and other sneeze-inducing plants has increased, with the largest increases coming in more northern locations.  These expansions are coming in line with increases in the length of the growing season.  Science Daily reported on a study from the University of Leicester, which showed that ragweed pollen has been observed there on four consecutive days, which has never happened before.  Ragweed pollen is seldom seen in Great Britain because it needs a long-lasting autumn before the first frost to flourish. Earth Gauge reported that the pollen season has increased in Papillion, Nebraska by 11 days, Fargo ND by 16 days and Winnipeg, Manitoba, Canada by 25 days.  Their brief article can be found here.