“Invasive Ecological Threat” (Florida Weekly, November 21, 2024):
A new invasive seagrass has been spotted off the waters of South Florida and scientists are working to see what danger it could pose for native seagrass and the plants, fish and marine animals they support.
The seagrass, called Halophila stipulacea, was discovered in a marina on Key Biscayne in Biscayne Bay. This is the first time it has been identified off the coast of the continental United States. The non-native species could be a threat, depending on whether or not the newcomer will compete with and displace our native seagrass species, said Justin Campbell, Florida International University marine scientist.
The invasive seagrass came from around the Red Sea and the Suez Canal area and is native to the Western Indian Ocean, Campbell said. It crossed the ocean, probably as part of boat passage from the Mediterranean, he said. It showed up in the Caribbean on the island of Granada around 2002. By 2017, it had spread to the Virgin Islands and Puerto Rico. “And then now, very recently, it has showed up on our doorstep here in Florida,” Campbell said.
The invasive species doesn’t look like our native seagrass, which has long leaves and tall, grass-like canopies. The invasive species has short, tiny leaves, he said. Scientists believe it has been spreading through a process of fragmentation or asexual reproduction. The species fragments very easily, meaning that small pieces can break off, Campbell said. “Those small fragments have the capacity to float for a week, ten days, and then potentially resettle in a new area and start growing again.” It’s essentially a clone of the parent fragment, he said.
“It’s really hard to predict what the consequences of this is going to be,” said James Fourqurean, a co-author of the research paper and director of the Coastlines and Oceans Division in FIU’s Institute of Environment. “This is a species that can spread incredibly rapidly. The meadows that were just discovered this summer (in the bay) are too large to have grown in a single year. So we know that it’s been here for multiple years already,” he said. The invasive seagrass will eventually spread even to the Gulf of Mexico, though not directly from Biscayne Bay, he said. “There’s no biological reason that it won’t grow all around the Gulf of Mexico,” he said. “It’ll get there. It’s just a matter of time.”
Noted.
Related:
- “Recent Immigration Surge Has Been Largest in U.S. History” (New York Times, Dec 11, 2024): Under President Biden, more than two million immigrants per year have entered, government data shows. The immigration surge of the past few years has been the largest in U.S. history, surpassing the great immigration boom of the late 1800s and early 1900s, according to a New York Times analysis of government data. Annual net migration — the number of people coming to the country minus the number leaving — averaged 2.4 million people from 2021 to 2023, according to the Congressional Budget Office. Total net migration during the Biden administration is likely to exceed eight million people. [There’s a chart showing that 190,000 net immigrants/year arrived in the 1850s compared to more than 2 million/year during Biden-Harris, but the bars are as a percentage of population so it doesn’t look like 10X the rate.]
