It is clear that the tide has
turned in the Salish
Sea
It we have learned anything it is
to apply cautious harvesting or even to sell specific harvests in perpetuity to
operators responsible for optimizing the production over time. I prefer this because it puts vested boots on
the ground who will adamantly intervene when competing self interests threaten
to risk the stock. This article reveals
just how sensitive things are to harvesting distortions.
Before this is finished, the Salish Sea Fraser
River
What this article shows is that
all the historic biodiversity is reestablishing itself to full flood. I expect we will see many monster Sockeye Salmon
runs as we did in the past couple of years to remind us of what we are
protecting.
Marine mammals coming back to the Salish Sea
The shared inland waters of Juan de Fuca Strait, B.C.’s Strait of
Georgia, and Washington state’s Puget Sound may once again approach its former greatness
LARRY PYNN, Vancouver Sun
Published: Friday, April 13, 2012
Tides come and go in the Salish
Sea
Sometimes entire species vanish almost unnoticed on the ebb of history.
And sometimes - to widespread astonishment - those same species ride
the currents of conservation back home again.
Humans have exacted a terrible toll on our region's marine life over
the past 150 years, through commercial whaling, reckless overfishing, and bounties,
culls, and commercial harvests of harbour seals and sea lions.
Without question, the ecological effect of those actions continues to
be felt today.
But there are also signs that the Salish
Sea - the shared inland waters of Juan
de Fuca Strait, B.C.'s Strait of Georgia, and Washington
state's Puget Sound - is stirring and, who
knows, may once again approach its former greatness.
Thanks to conservation efforts, one marine mammal after another is
making a dramatic comeback, their presence providing the biggest reason for
hope across an ecosystem spanning 7,000 square kilometres.
Steller sea lions have thrived since the federal government afforded
them protection in 1970 - with new abundance estimates pegging their population
at 48,000 animals in winter on the B.C. coast.
The breeding population had dipped to an estimated 3,400 animals before
their protection.
Similarly, harbour seals today total an estimated 105,000 animals, one
of the densest such populations on earth, compared with fewer than 15,000 in
the late 1960s.
All those nutritious blubbery bodies are proving irresistible to
mammal-eating killer whales known as "transients."
About 120 transients are known to visit the Strait
of Georgia , surpassing an endangered population of fish-eating
resident killer whales thought to number 88 in three pods - a story that sadly
runs counter to the others.
Humpback whales are now found year-round on our coast, while a
genetically distinct population of grey whales with unique feeding habits makes
regular forays off Vancouver
For the first time in memory, fin whales - the second largest animal on
earth, after the blue whale - have been spotted near the north end of the
Strait of Georgia past Campbell River.
Hundreds of Pacific white-sided dolphins now call the strait home,
including Howe Sound - an area that is experiencing an ecological reawakening
after the treatment of mine effluent, the closure of a pulp mill, and the
restoration efforts of local streamkeepers.
And the car-sized northern elephant seal - once reduced to fewer than
100 individuals - now numbers up to 200,000 from Mexico
to Alaska
The dramatic return of so many marine mammals at the top of the food
chain also suggests good productivity at the bottom, for predators cannot
thrive without the fish and smaller creatures upon which they prey. But there
are also dozens of species that are not doing as well in the Salish Sea
A study by the SeaDoc Society - based in the San Juan Islands and
affiliated with the Wildlife Health Center at the University of California,
Davis - has found a total of 113 species to be threatened, endangered, or
candidates for listing by state, provincial or federal levels of government.
Included in the most recent count: 56 species of bird such as the
western grebe and Brandt's cormorant; 37 fish such as salmon and rockfish; 15
mammals; three invertebrates; and two reptiles.
Those 113 threatened species are almost double from the 64 identified
two years ago, a reflection, in part, of a growing awareness among government
managers who officially list species as being at risk.
It's a critical step in the recovery process.
As marine mammals have shown, sometimes the public policy fixes are
simple. All it took was for governments to formally put an end to the killing
to allow populations to begin to recover.
Other species are not so easy.
The challenges are greater with, say, salmon, whose survival depends
equally on protected spawning habitat far upstream from the Salish Sea, or
birds that depend on nesting grounds as far north as the Arctic.Scott Wallace
is a sustainable fisheries analyst with the David Suzuki Foundation who studied
changes in the ecology of the Salish Sea ecosystem over a century as part of
his PhD thesis 15 years ago at the University of British Columbia.
Pointing to depressed stocks of groundfish species such as rockfish,
lingcod, halibut, and Pacific cod in the strait, he questions whether the Salish Sea
Still, there remains much to be celebrated. "It is by no means a
dead sea," he emphasized. "It's a thriving live ecosystem, still
extremely productive - an incredible resource on the back door of a major
city."
There are many factors conspiring against a comeback, some direct, such
as fishing and habitat destruction, and some more subtle, like the long-term
threats of climate change.
Ocean warming is predicted to reduce the amount of oxygen for fish
while pushing more southerly species such as the ravenous Humboldt squid
further north - with potentially dire consequences for local marine stocks.
Warming rivers will become increasingly inhospitable to spawning salmon
and oolichan.
Increased acidification of the oceans under climate change will compromise
marine productivity at the base of the food chain.
An expanding human population is exacting an ever-greater toll -
pollution, shoreline development, noise and harassment from marine traffic,
including from navy sonar and explosions.
And, of course, there is the age-old competition between human and wild
predators for the same prey fish.
"There's been a conflict almost as long as people have been
catching fish," said Andrew Trites, director of the marine mammal research
unit in the Fisheries Centre at UBC.
"Society has to decide how they want these fish allocated."
Whereas in the past we shot species such as seals and sea lions and
captured killer whales for public display, including at the Vancouver
That process has already begun in the Salish Sea
Canada's federal fisheries department and the U.S. National Oceanic and
Atmospheric Administration are holding a series of meetings aimed at managing
chinook salmon stocks to ensure the needs of killer whales are met.
Co-managing species that share international waters is the wave of the
future, says Rob Williams, a research fellow with the sea mammal research unit
at the University of St. Andrews in Scotland
"That would be progressive by any country's standards, making sure
that a valued and critically endangered predator gets access to prey," he
said. "If we can do that with killer whales, we should be doing it with
sharks, seabirds, and all sorts of things."
And killer whales have big appetites, especially for the largest
species of wild Pacific salmon, the chinook, according to a study published in
November 2011 in the online scientific journal PLoS ONE.
The study concluded it takes the equivalent of 660 chinook a day to
feed all the southern residents, which consume between 12 per cent and 23 per
cent of the Fraser
River
If their population recovers to 155 animals by 2029 - the goal of a U.S.
While humans may have to forgo some of their catch to help killer
whales in the short term, the ultimate objective is to produce more salmon for
all through measures such as habitat enhancement, including protection of
critical spawning habitat and restoration of other stretches damaged over the
generations.
"Especially with salmon, we have to make more," says
Williams, the study's lead author.Competition between humans and marine mammals
does not stop at salmon, but extends all the way down the food chain in the
Salish Sea to include species such as herring and tiny, shrimp-like krill.
Ottawa sets an annual catch limit of 500 tonnes on krill, a fishery is
conducted at night with beam trawls when the schools rise closer to the
surface.
The U.S.
Krill is used by places such as the Vancouver
Aquarium and California 's Monterey Bay
Aquarium, which gets its supply from Canada
Meanwhile, herring roe goes to Japan
Some say it is folly to harvest the ecological underpinnings of the Salish Sea
"That is a disgrace, a damn shame," said professor Dan Pauly
of UBC's Fisheries Centre. "There is not much as good as herring, smoked
or fileted or pickled."
Lisa Mijacika, herring coordinator for the federal fisheries
department, said the strait's stocks are estimated at 138,000 tonnes, of which
18,000 tonnes, or 13 per cent, were designated this year to sectors such as
commercial roe, food and bait.
"It's reasonably conservative in our view," she said, noting
a 20-per-cent catch would have been sustainably justified.
Wallace, of the David Suzuki Foundation, sits as the conservation
representative on a federal herring planning committee and says the krill
fishery is not a conservation risk at current levels and that he considers the
herring fishery to be "relatively well managed."
Recovering herring stocks are a symbol of the improving ecological
health of Howe Sound.
Volunteer streamkeepers are credited with wrapping pilings with plastic
to protect herring roe from toxic creosote, while the shutdown of the Woodfibre
pulp mill in 2006 and construction of a plant in 2005 to treat toxic mine
drainage on Britannia Creek resulted in the return of about two dozen pink
salmon last year.
"Howe Sound is a striking change," confirmed Lance
Barrett-Lennard, a marine mammal scientist with the Vancouver
"One way or another, we seem to be seeing that inlet come back to
life."
Habitat improvements could be proving beneficial for long-depressed
rockfish populations, too.
Black rockfish vanished from our local waters "in the days of The
Sun Salmon Derby
"You couldn't help but catch them, they're such aggressive
lure-strikers. Easier to catch than coho."
Now, Marliave said, there are signs that black rockfish transplanted by
the aquarium from 1997 to 2006 at Lighthouse
Park in West Vancouver
"We've got herring, we've got feed," he said. "It has to
do with the whole ecology. We have something big happening locally."
As scientists grapple to understand changes in the Salish Sea
Fishermen who curse harbour seals for stealing salmon off their lines
may not realize that seals' year-round diet can also benefit stocks of the
prized catch.
One study in the Strait of Georgia found
that while harbour seals are opportunistic predators, hake - a predator of
young salmon - and herring account for about 75 per cent of their total diet.
And new research is underway at UBC to better determine their eating habits.
Other studies are shedding more light on the complex and unexpected
interactions between marine life.
When seals were culled in Alaska 's Copper River delta in the 1960s to reduce predation on
salmon, it resulted not in increased salmon but a failure of the razor-clam
fishery. The shortage of predators allowed the starry flounder, another primary
element of seals' diet, to feed on the clams unchecked.
Similarly, while sea otters off Vancouver Island
consume the same sea urchins enjoyed by humans, the harvest of urchins allows for
the growth of kelp beds that enhance the overall marine diversity.
"We shouldn't trust our eyes because there is a lot happening
below the surface that we don't know," says Pauly of UBC's Fisheries
Centre. Trites, his colleague at the Centre, concurs: "Often there are
indirect effects that we cannot anticipate."
While the interconnection between marine mammals and their prey may
fall off the radar for most of us, the link could not be more evident to John
Ford, a federal biologist with the cetacean research program based in Nanaimo
Looking out across Departure Bay , he can watch both Steller and California
On another day, the tides will turn and the sea lions will find
themselves prey for the transient killer whales.
Rare in the Strait of Georgia as
recently as the mid-1970s, the transients have been increasing steadily at two
to three per cent per year.
In comparison, the 88 southern resident killer whales are down from 98
animals in 1995, a decline that coincided with a period of low chinook salmon
runs.
In 2001, there were just 80 residents - in human terms, about the size
of a block party.
Transients are highly mobile, making it difficult for scientists to
identify critical habitat.
But they can now be found here all year, peaking in late August and
September when harbour seal pups are weaning and most numerous.
Some scientific observers ask what took them so long to discover the
easy meal options afforded in the Salish
Sea
"I was puzzled, for years we had this big increase in harbour
seals, and the transients didn't seem to catch on right away," said
Barrett-Lennard of the Vancouver
The transients are not the only whale comeback success story in the Salish Sea
Humpbacks have been increasing in B.C. waters at four to six per cent
per year, with the population locally estimated at 2,600 individuals, part of a
north Pacific population estimated at 18,000. The population is thought to have
dropped to as low as 1,500 animals in the 1960s.
Commercial whaling occurred in local waters in two waves, from the late
1860s to early 1870s and again in 1907. Just eight whales rendered in Saanich
Inlet in 1868 yielded 45,500 litres of oil.
Along the outer coast, five whaling stations killed at least 24,250
whales from 1907 to 1967, when whaling ended.
Today, humpbacks have made a strong recovery. Sightings of the animals
are routine in the Strait of Georgia, including off Victoria ,
the Gulf Islands ,
Nanaimo and Sunshine Coast
While the vast majority of B.C.'s humpbacks migrate to Hawaii or Mexico
As long as these whales have food and clean habitat without undue
harassment and noise from vessel traffic they should continue to thrive, said
Ford, of federal fisheries.
However, humpbacks return each year to within a few kilometres of their
feeding grounds, meaning they are slow to recolonize areas where they were
depleted by commercial whaling. And females bringing back young from tropical
waters will introduce them to traditional grounds, behaviour that's led to
about 50 humpbacks now found off Telegraph Cove on northeastern Vancouver Island .
Another success story are the grey whales in the eastern north Pacific,
which have rebounded after a setback between 1999 and 2000.
The population dropped by up to 25 per cent that year, with strandings
commonplace along their migration route, including on the beaches off White
Rock, Tsawwassen and the Gulf Islands.
Scientists blamed the problem on poor feeding conditions in the Bering Sea , where excessive ice prevented the whales from
accessing their shallow feeding grounds.
"They started their migration in poor condition and ran out of gas
on the way back," said Ford, speculating they swam into shallow, muddy Boundary Bay
Current numbers are estimated at 18,000 to 20,000, and researchers are
finding some startling genetic and behavioural differences in the local
population.Jim Darling, a marine biologist with B.C.'s Pacific WildLife
Foundation, said that rather than migrate to Arctic waters with the rest, about
200 whales - or one per cent of the population - remain along the coast between
northern California and southeastern Alaska.
The west coast of Vancouver Island is a key feeding area for this
group, although individuals have turned up in Howe Sound, False Creek, and
several can linger for months in Boundary
Bay
Genetic tests of mitochondrial DNA passed on by mothers to offspring
show B.C.'s grey whales are "genetically distinct" and should be
managed separately from the overall population, Darling said, a finding that
has implications for the whaling aspirations of aboriginal groups such as the
Makah of the Olympic Peninsula and Nuu-chah-nulth of Vancouver
Island .
In effect, B.C.'s grey whales have a culture that is distinct from the
larger population.
"My hunch is they've been here for as long as there's been a
coast," Darling said. "Their knowledge and behaviour have been passed
down from one generation to the next."
After studying whales since the 1970s, Darling laments that management
decisions on whales continue to be based on limited knowledge at best and often
no knowledge at all.
"We tend to think of them as the same, clones of each other, think
of them as numbers, but that is not the case."
Despite the myriad of management dilemmas and ecological uncertainties
swirling about the Salish
Sea
One need only recall the public and media frenzy that arose when a grey
whale swam into False Creek in May 2010 and again off West
Vancouver and Stanley
Park
People thronged the seawall in a bid to catch a glimpse, some paddling,
even swimming out for a closer look.
Whales fill us with hope.
If something so big can flourish here, maybe in time the smaller and
less obvious parts of the puzzle can, too.
Their return to Vancouver gives us pause
to consider past mistakes and the promise ahead for a vibrant Salish Sea
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