FRISCO — Biologists looking at 40 years of fisheries data from Puget Sound have documented a dramatic shift in marine species. Key fish in the food chain, like herring and smelt, have declined, while the number of jellyfish has increased exponentially, to the detriment of the marine ecosystem.
More long-term and widespread monitoring needed to pinpoint trends
By Summit Voice
FRISCO —Global jellyfish populations appear to fluctuate on a decadal basis, including an increase in the 1990s and early 2000s that has led to the current perception of an overall global increase in jellyfish abundance.
The researchers did find a hint of a slight increase in jellyfish since 1970, although this trend was countered by the observation that there was no difference in the proportion of increasing vs. decreasing jellyfish populations over time. Continue reading “Study eyes global jellyfish populations”→
Study finds increased abundance in areas affected by human development
By Bob Berwyn
SUMMIT COUNTY — Jellyfish populations are growing in many of the world’s coastal ecosystems, especially in areas affected by pollution, overfishing, and warming waters, according to a new study done by researchers with the University of British Columbia.
“We found numerous types and species of jellyfish that appear to be increasing, so the reported increases are certainly not due to one type jellyfish in particular,” said Lucas Brotz, a PhD student with the Sea Around Us Project at UBC and lead author of the study.
“That being said, there are several species of jellyfish that appear to be highly invasive are invading new regions around the globe all the time (probably due to transport from cargo ships),” Brotz said via email. ” The most notorious of these is a comb jellyfish called Mnemiopsis leidyi which is showing up in new places every year and often rapidly increases in abundance, potentially altering the ecosystems it invades,” he said. Continue reading “Jellyfish numbers growing in many coastal ecosystems”→
SUMMIT COUNTY — A decent week for page views at Summit Voice, with a Google News link for our jellyfish story driving page views to more than 6,000. It’s the first time we can remember that we’ve had four stories with 1,000 page views or more, including a couple of climate science articles and a quick blurb on the Front Range snow storm. Click, read and share with the social media buttons at the end of each post.
Balance of ocean food web at risk as jellyfish blooms increase
By Summit Voice
SUMMIT COUNTY — Warmer water temperatures, over-fishing and nutrient loading in coastal areas could result in a jellyfish takeover, according to a team of biologists who studied the role of the slimy floaters in marine ecosystems.
The scenario might be good for a jellyfish lover like the cartoon character Spongebob Squarepants, but as numbers of jellyfish increase, they could tip the balance of ocean food chains away from fish and toward bacteria, the scientists with the Virginia Institute of Marine Science wrote in a paper recently published in the Proceedings of the National Academy of Sciences.
Jellyfish eat huge amounts of plankton, which is also the most important food for small fish at the base of ocean food chains. But jellyfish are not a significant food source for other animals and their waste products add almost nothing useful to marine ecosystems. Continue reading “Environment: Jellyfish may get last dance”→