For repeat-spawning steelhead, more than once is worth the risks/
April 15, 2018
The Coos Bay World by Steve Lundeberrg
CORVALLIS, Ore. — For steelhead trout, reproductive choices represent a collection of tradeoffs – whether spawning once or doing it multiple times, no decision comes without risks and benefits.
New research by Oregon State University and Purdue University shows steelhead that spawn repeatedly have greater than double the lifetime reproductive success of fish that spawn a single time, the benefit for making the daunting journey to sea more than once.
Findings, which could lead to more effective conservation efforts, were published this week in the Proceedings of the National Academy of Sciences.
Like salmon, steelhead – Oncorhynchus mykiss – are anadromous, meaning they travel to the ocean as smolts and return to their natal streams to spawn; unlike salmon, steelhead are not limited to spawning once and then dying.
Female steelhead build gravel nests called redds into which they deposit their eggs, and males vie to fertilize them.
The research by OSU’s Michael Blouin and Purdue’s Mark Christie involved more than 12,000 winter-run steelhead from Oregon’s Hood River, with the researchers looking at number of lifetime spawning events and age at first spawning.
“We found that repeat-spawning fish had more than 2.5 times the lifetime reproductive success of single spawning fish,” said Blouin, professor of integrative biology. “However, first-time repeat spawning fish – ones having the first in a series of spawning events – had significantly lower reproductive success than single-spawning fish of the same age. That suggests repeat-spawning fish hold some energy back from reproduction to devote additional energy to continued survival.”
As with salmon, steelhead that spawn only once die after doing so.
“There’s a tradeoff between saving energy to successfully survive that additional migration event to the ocean and putting all of their eggs in one basket, so to speak,” said Christie, assistant professor of biological sciences at Purdue and a former Oregon State postdoctoral scholar.
The risk of going to sea is illustrated by the finding that less than 3 percent of the fish in the study were found to be repeat spawners.
In addition to the trip, it’s also more dangerous for a steelhead just to be in the ocean than in freshwater – but months and years at sea also allow the chance to gain size, strength and improved reproductive prowess.
“The expectation is that the more time they spend in the ocean, the higher the payoff will be to offset the risk of predation and other hazards,” Christie said. “We’d expect them to come back to their spawning grounds bigger and stronger, and that’s definitely what we see in male fish.”
Not so with females, who showed the highest reproductive success at age 3, despite being smaller than 4- and 5-year-old fish.
Why? Because of “negative frequency dependence,” Blouin said: the idea that a rare life history strategy correlates with greater fitness.
A life history strategy is how an organism parcels out energy for growth, reproduction and survivorship.
“Negative frequency dependence dictates that selection favors the rarest life history strategies,” he said. “In this study, we show that the older, larger female fish have higher reproductive success when they are less common, perhaps due to decreased competition.”
“Fitness tradeoffs” are the other factor at work, Blouin said.
“The costs and benefits associated with each strategy prevent any one strategy from becoming permanent,” he said. “If there is too high mortality associated with going out to sea, the repeat spawning strategy would never evolve. But if it’s low enough, and if there’s a fitness benefit, which we’ve shown there is, these two life history strategies can coexist.”
Findings suggest that restricting the harvest of older, larger females when their numbers are lower than average might foster negative frequency dependent processes, thus helping to maintain population diversity and reverse declines in populations.
The Oregon Department of Fish and Wildlife also collaborated on this research, which was funded by the Bonneville Power Administration and Purdue University.
Klamath River salmon season set to reopen in May; other regions face restrictions
April 12, 2018
Eureka Times Standard By Will Houston, Eureka Times-Standard
After facing closures for up to two years because of low salmon returns, Klamath River salmon fishermen and tribes are gearing up for a chance to make up for some of their losses in 2018.
But the Klamath River season appears to be the only silver lining in California’s salmon season, according to fishery officials, with fishermen further south facing a potentially meager season asa result of low returns of Sacramento salmon.
Humboldt Fishermen’s Marketing Association President Harrison Ibach described this year’s season as odd in that the Klamath River salmon fishery has a longer summer season than fisheries down south when he said it’s normally the other way around.
“As a whole, this season is very, very restrictive and going to be fairly devastating for a lot of salmon fishermen,” Ibach said. “But that we get a little season here is nice and it will help a little bit.”
The Klamath River’s sport and ocean salmon seasons were closed last year because of an unprecedented low prediction of returning Chinook salmon.
Last year, the Yurok and Hoopa Valley tribes were allocated just over 800 Chinook salmon, the lowest on record. The Yurok Tribe closed its commercial fishery for the second year in a row as a result and harvested only 216 fish for ceremonies and for tribal elders. The Hoopa Valley Tribe harvested 1,660 fish last year, which federal agencies and the Yurok Tribe have deemed as overharvesting though the Hoopa Valley Tribe challenged that claim.
This year, the tribes are set to be allocated more than 18,000 fall-run Chinook salmon.
The 2018 salmon harvest rules for the West Coast were approved this week by the Pacific Fishery Management Council after several days of meetings. The rules for salmon and other fisheries are expected to be approved by the National Marine Fisheries Service by May 1.
Ibach said this is the first time in about five years he can remember being able to fish for Klamath salmon in May, which he said is a nice change of pace.
The fishery council’s California troll salmon adviser Dave Bitts of Eureka said normally about 80 percent of the year’s salmon catch occurs in July, but the season will only be open for six days that month in the Fort Bragg and San Francisco areas because of the low predicted return of Sacramento River salmon.
Pacific Coast Federation of Fishermen’s Associations Executive Director Noah Oppenheim — who represents fishing fleets from San Diego to Alaska — said this year’s salmon season rules make it “clear as day that the drought is not over for salmon fishermen, who continue to pay for terrible water policy decisions with their livelihoods year after year.”
“With the Sacramento River salmon stock constraining us, it took a lot of hard work and collaboration just to patch together the meager season we’re facing for 2018,” he said. “But there will be California salmon on the menu and in the cold case this summer. We’ve finished the season setting process, and our members are looking forward to finally getting back out on the water. It’ll be tough, but we will persevere.”
Bitts said the predicted return of Sacramento River salmon is very conservative this year and for good reason.
“They were badly overpredicted for three years in a row,” Bitts said.
By reigning in the harvest of Sacramento salmon this year, Bitts said the idea is to allow for more fish to be able to spawn and restore the stock. At the same time, Bitts said fishing vessels in San Francisco reported seeing an abundance of smaller salmon last year, which he said could indicate the return of Sacramento River salmon will be higher than predicted.
“If that turns out to be true, then we may not have a whole lot of time, but the time should be productive compared to last year,” Bitts said.
Ibach said with ocean fishing in the Klamath Management Zone — which runs from the California-Oregon border to Humboldt Bay’s south jetty – being open earlier this year, it may attract more fishermen from southern areas of the state.
While Ibach said he wishes the salmon season could be open for longer, he said that is not always the case.
“We’re appreciative to get as much time as we can get to go to work,” he said.
Fishing the North Coast: Salmon opener slated for June 1
April 11, 2018
Eureka Times Standard By Will Houston
After suffering through a complete shutdown of our salmon season in 2017 within the KMZ, one thing is for certain – absence truly does make the heart grow fonder. Halibut and rockfish are fun, but salmon is king in Eureka – always has been, always will be. And not being able to fish for them last year really stung. Needless to say, there were a lot of nervous anglers waiting while the different agencies poured through data last month trying to determine what our ocean salmon season would look like in 2018 – or if we’d even have one.
In all my years living here, I can’t recall such anticipation and excitement revolving around the recreational salmon opener. What was once just a mere formality, has taken on the feel of a lottery. While the PFMC were holed up in Portland this week crunching the final numbers and doing their best to divide the salmon numbers across the entire state, local anglers held their collective breath. When it was all said and done on Tuesday, the outcome was just what we wanted to hear. The North Coast will have a salmon season, and a lengthy one at that.
Encouraged by a recovering Klamath River fall Chinook stock, the PFMC adopted a very generous season for the California KMZ, which runs from the CA/OR border south to Horse Mountain. The season will run from June 1 straight through September 3. Fishing will be allowed seven days per week for all salmon except Coho, two fish per day and a minimum size limit of 20 inches total length for Chinook. According to the PFMC, 359,200 Klamath adult salmon are swimming in the ocean, opening the door for fall salmon seasons on the Klamath and Trinity Rivers as well. Though still awaiting approval from the F&G Commission, the sport in-river quota will be 3,490 adults divided between the two rivers.
With only 229,432 Sacramento fall Chinook said to be swimming in the ocean, the seasons to our south were a little more restricted this year. The area from Horse Mountain south to Point Arena, which includes Shelter Cove and Fort Bragg, will open on June 17 and run through Oct. 31. The San Francisco area will have the same season opening and closing dates. To the north in the Brookings area (Oregon KMZ), the season will open on May 19 and run through Aug. 26. Fishing will be allowed seven days per week for all salmon except Coho, two fish per day and a minimum size limit of 24 inches total length for Chinook. For more information on both the recreational and commercial fishing seasons, visit https://www.pcouncil.org/wp-content/uploads/2018/04/T2_Sport_draft-041018.pdf
Low predicted salmon returns lead to shortened season, smaller chinook quota
April 11, 2018
The Daily World
Small quotas and a limited season will be the reality for salmon fishermen this summer in the waters inside and outside Grays Harbor and Willapa Bay.
“It’s critical that we ensure fisheries are consistent with ongoing efforts to protect and rebuild wild salmon stocks,” said Ron Warren, head of the state’s Department of Fish and Wildlife fish program. “Unfortunately, the loss of salmon habitat continues to outpace these recovery efforts. We need to reverse this trend. If we don’t, salmon runs will continue to decline and it will be increasingly difficult to develop meaningful fisheries.”
Salmon fishing seasons were set Wednesday by the Pacific Fishery Management Council, which approved a recreational chinook catch quota of 27,500 fish, which is 17,500 fewer fish than 2017’s quota of 45,000. The council, which establishes fishing seasons in ocean waters three to 200 miles off the Pacific coast, also adopted a quota of 42,000 coho for this year’s recreational ocean fishery – the same as last year’s coho quota.
Marine Area 2, out of Westport, will only be open Sunday through Thursday starting July 1. The ocean salmon fisheries out of Ilwaco, La Push and Neah Bay will be open daily beginning June 23. All marine areas will close Sept. 3 or sooner if quotas are met. The limit will be two salmon daily, only one of which may be a chinook, in all areas except La Push, where the limit will be two salmon daily. In all areas, wild coho must be released.
In the Grays Harbor area, the Area 2-2 Humptulips North Bay chinook fishery begins in August and runs through Sept. 15. The Area 2-2 East Bay coho fishery begins two weeks later than 2017 and is scheduled for Oct. 1-Nov. 30. The Chehalis River spring chinook fishery is scheduled May 1-June 30 while the jack fishery in the lower river runs Aug. 1-Sept. 15.
The Humptulips River is scheduled to be open for salmon fishing Sept. 1-Nov. 30, about two months fewer than last year. Anglers can keep one wild chinook during the month of September but must release wild chinook the remainder of the fishery.
As for the Willapa Bay area, the season will be similar to last year’s and is scheduled Aug. 1-Jan. 31. Anglers can keep three adult salmon, one of which may be a coho. The freshwater rivers in the Willapa Bay area have similar seasons to 2017. Anglers may retain one wild coho.
“No fisherman wants to catch the last salmon,” said Lorraine Loomis, chair of the Northwest Indian Fisheries Commission. “We must work together if we are going to restore salmon to sustainable levels.”
Too Many Salmon in the Sea?/Record-setting abundance of some salmon in the North Pacific may be having negative impacts
April 10, 2018
NCEAS by Jenny Seifert
The notion that there can be too many salmon in the sea might seem preposterous, especially given how many people love to eat them, but according to a new study, there is a record-level abundance of certain species of North Pacific salmon, and it may be contributing to a troubling trend: depleting stocks of other salmon species, especially the prized Chinook salmon.
The study, published April 4th in the journal Marine and Coastal Fisheries, shows the number of pink, chum and sockeye salmon have been more abundant during the past 25 years than they have ever been since 1925, when the recordkeeping began. In the ten-year period of 2005 to 2015, an average of 721 million salmon were swimming in the sea each year, which is approximately 36 percent more than their previous peak in the late 1930s.
"While it is good that the abundance of sockeye, chum, and pink salmon is high, there is growing evidence that this high abundance, especially of pink salmon, is impacting the offshore ecosystem of the North Pacific and Bering sea,” said lead author Greg Ruggerone, a scientist at Natural Resources Consultants, INC. “These impacts may include the decline of higher trophic species of salmon, such as Chinook salmon in Alaska, the size, age and abundance of which has declined in recent decades even though their habitat is largely intact.”
All species of Pacific salmon migrate thousands of kilometers through the open ocean in search of food, and the abundance of pink, chum and sockeye in the northern regions may be due to more favorable waters. Not only is habitat in the north less degraded than in other areas, the waters are also warming under climate change, making conditions cozier for them.
The authors’ estimates, which are based on the most comprehensive compilation of abundance data to date, accounted for salmon born in both natural conditions and hatcheries throughout their native range in Asia and North America. Hatchery-born salmon represented about 40 percent of the seafaring adult and immature salmon.
Most of these hatchery salmon are chum, which typically spend more years at sea than their fellow salmon species before returning to freshwater spawning grounds, the final destination of any uncaught salmon’s life journey.
Pink salmon were the most abundant overall, representing nearly 70 percent of all wild and hatchery Pacific salmon combined. While most pink are wild, the numbers born in hatcheries in the past 25 years have been exceptionally high at an average of 66 million adults per year, a number that exceeds total wild chum populations.
High overall abundance can be a good thing, especially when it constitutes mostly wild salmon, but the authors explain the tremendous abundance of hatchery salmon, especially of pink, may be causing the North Pacific to reach its carrying capacity.
For example, there is growing evidence that the highly dense populations of pink – the least desirable species for its small size, soft and pale meat and short shelf life – are impacting the growth and survival of the more prized, but less plentiful Chinook and coho.
Ruggerone explains their study highlights the importance of maintaining and improving efforts to monitor the numbers of hatchery salmon in fisheries harvests and spawning grounds to keep a better pulse on the status of wild salmon. Tagging or marking hatchery salmon to make them more identifiable when caught or spawning, as well as making the resulting data publicly available, are critical to preventing adverse effects on the growth and survival of wild salmon.
“Ultimately, we want fisheries agencies in all areas of the Pacific Rim to estimate the numbers of hatchery and wild salmon as a means to monitor wild salmon status,” said Ruggerone, adding that at the bottom line is the need to maintain habitat to support wild salmon abundance into the future.
This study is the first to emerge from the State of Alaska Salmon and People (SASAP) project, a partnership between the National Center for Ecological Analysis and Synthesis (NCEAS) and Anchorage-based Nautilus Impact Investing that is funded by the Gordon and Betty Moore Foundation.