Like clockwork, the herring of Howe Sound find their way to shore around Feb. 1 each year and deposit eggs in significant numbers.
Conservationist and citizen scientist John Buchanan has seen this the last few years through his study of herring in the waters south of Squamish. Motivated by memories of jigging for herring at the tip of Howe Sound as a youth, Buchanan has been documenting the revival of the fish species.
Buchanan has reported that since about 2005 herring have made a significant comeback in Howe Sound after almost completely disappearing when he was young. He has been watching and documenting the revival by heading out in his boat to see where the eggs can be found and how thick the spawn is.
"I think they have increased from last year," Buchanan said of his Feb. 15 Howe Sound observation. "It seemed a little thicker and denser. It is so hard to tell because I'm only strictly surface."
Buchanan said he notes the facts — things like water temperature, GPS locations and salt levels then — shares his information with organizations like the Department of Fisheries and Oceans (DFO).
Buchanan's recent research mission took him along the west side of Howe Sound and he reported finding herring eggs along the shore just north of Woodfibre and south of Woodfibre to an area directly across the sound from Britannia Beach. He also found roe at the former Nexen chemical plant site.
Buchanan has high praise for the creosote piling wrapping program at Squamish Terminals. The Squamish Streamkeepers teamed up with other groups when it was observed that herring were unsuccessfully trying to reproduce by leaving eggs on the toxic pilings so the groups started wrapping the ocean posts.
While Buchanan praises the work of concerned citizens he is critical of provincial officials, who he has accused of underestimating the importance of removing old pilings that are no longer in use.
"Both the Nexen area and the Woodfibre area, I think at Woodfibre I counted well over 1,000 creosote pilings in there," said Buchanan. "They're in different conditions of falling apart and these are old industrial sites, both of which had been cleaned up, but the province doesn't seem to take on the creosote."
Through his work Buchanan said he has learned that a long list of species feed on herring roe. He spotted elk at the shoreline near Woodfibre two years ago feeding on the eggs while the tide was low.
"As soon as you get a healthy herring population everything benefits," said Buchanan.
He feels the growing herring population played a role in attracting dolphins and whales back to Howe Sound.
Buchanan's work is being done while the Vancouver Aquarium continues with its ongoing Howe Sound Research Project. Dr. Jeff Marliave has been observing changes in Howe Sound dating back to the 1980s and he said the work of a number of citizen scientists in Squamish is contributing greatly to our herring knowledge. Marliave applauds the efforts the Streamkeepers in giving the herring clean pilings to ensure their eggs survive but he believes climate impacts the herring population more than the good work of humans.
"This is a really interesting recovery," said the aquarium vice president of marine sciences.
"The herring have bounced back during back-to-back La Niñas and now we're officially in the very rare status of being in a normal winter. When herring were really abundant, when salmon were really abundant, that period from the late '40s to 1979 was a cool period," said Marliave. "That was a relatively long, cold climate regime and a lot of fisheries scientists now say that fisheries maybe has some effect but climate really causes (the most significant change)."
Marliave said herring prefer cold La Niña periods so the cooler winters have been good for the species in Howe Sound.
Marliave was a guest of the DFO this summer during a trawl of Howe Sound and based on the findings from that trip Marliave concluded that Howe Sound herring don't migrate out to open ocean as previously believed.
Jake Schweigert, the section head for conservation biology with DFO, said the herring population in Howe Sound isn't as significant as the populations found off Denman and Hornby Islands or the east side of Vancouver Island and because of that DFO pays greater attention to those larger herring groups.
Schweigert attributed the growing herring population in Howe Sound, at least in part, to the reduced amount of industrial activity taking place at the north end of the fjord.
"We may be seeing some rebuilding as a result of some of the clean up in Howe Sound," said Schweigert.
Herring reach sexual maturity at about three years and the mature fish can live as long as 20 years. According to Buchanan, mature herring are more production than younger herring.