An invasive crab lurks among the native species of the Salish Sea, but where they appear next is relatively unknown.
Across Greater Victoria, signs at busy beach accesses alert visitors to be on the lookout for this small crab that can irreversibly alter ecosystems.
The European green crab is present all the way up the west coast, but that invasion has been going on for over two decades, said Tom Therriault, a research scientist with Fisheries and Oceans Canada (DFO).
First found on the east coast in 1951 in the waters off New Brunswick, they have expanded to many locations in the Atlantic. In the west, the European green crab likely arrived in the late 1990s through larval transport.
They moved naturally, through larval drift, up the West Coast and were first reported on the U.S. side of the border in fall 2016, with subsequent discoveries in 2018. They remain pretty sporadic on the Canadian side, Therriault said.
Now they香蕉视频直播檙e found along the entire west coast of Vancouver Island. Whether the invasive crab is crawling up the inside coast remains largely unknown.
READ ALSO:
The DFO is working with local government and staff in Haida Gwaii to create delineation there 香蕉视频直播� the furthest north they香蕉视频直播檝e encountered adult crabs 香蕉视频直播� after multiple sightings were documented in July 2020.
香蕉视频直播淲e香蕉视频直播檙e now seeing conditions outside the 香蕉视频直播榥ormal香蕉视频直播� for us in B.C. and we don香蕉视频直播檛 necessarily understand how that香蕉视频直播檚 going to affect the invader,香蕉视频直播� Therriault said. Extreme weather events, such as last summer香蕉视频直播檚 heat dome and changing precipitation patterns, can shift the ecology and if that proves in favour of green crab larvae, they could flourish.
READ ALSO:
The European green crab is one of the 10 most unwanted species in the world, according to the DFO.
It destroys beds of shellfish and feeds on native animals such as clams, oysters, mussels, small fish and young crabs and lobster 香蕉视频直播� often beating native species to the buffet.
While there香蕉视频直播檚 no reason not to expect to see a green crab on Island beaches, it香蕉视频直播檚 impossible to have site-specific predictions, Therriault said. For that reason, signs dot the busiest beaches in Greater Victoria and elsewhere on Vancouver Island. The signage targets high-use beaches to educate those flipping rocks and taking walks about what is native and what is critical to report.
One key identifier makes the outlier obvious 香蕉视频直播� five clear spines on the side of each eye. While called green, it could be yellow, orange, or mottled and can be as large as four inches across.
Anyone who finds a European green crab on Vancouver Island shorelines should report the invasive species. Take photos and note the exact location, with GPS coordinates if possible, along with the date and identifying features. DFO can be reached toll free at
READ ALSO:
Do you have a story tip? Email: c.vanreeuwyk@blackpress.ca.
Follow us on and and like us on
