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For the past few years, the Snake River salmon of & # 39; Idaho and the Puget Sound Orcas were bound during the battle & # 39; scores & # 39; years over the fate of four & # 39; River Dams lower Snake and whether they should be removed to save the fish.
The orcas, specifically the southern resident whales, located in & # 39; difficulty and have been for some time. That came in & # 39; severe situation this summer when a member of the J-pod, a subgroup of orcas Puget Sound, carried his dead calf for 17 days and attracted media attention worldwide .
Whales face failure & # 39; food, noise from ships in Puget Sound crowded and accumulation & # 39; pollutants in their body fat. All three are linked, but what it boils down to the whales are not enough to eat, and eat what is most salmon.
This is where comes the salmon spawning in the Snake River Basin. The whales prefer Chinook salmon and eat number & # 39; & # 39 different stocks; above and & # 39; below West Coast & # 39; the United States and Canada. For most of the year, from spring to fall, the whales jippreżaw on Chinook returning to rivers that descend into Puget Sound and the Salish Sea, b & # 39; in particular x-Fraser of Canada River . But they also leave the inland in the autumn to travel along the coast looking for salmon, and less frequently in other species, before returning in the spring.
One of the stocks of whales goals during that period are those originating from and returning toward the Columbia River and its tributaries. That brings in the Snake River. The Orca lawyers formed a philosophical alliance and strategic with supporters of River salmon Snake believe that breaking the four & # 39; dams on the Snake River to & # 39; below will strengthen b & # 39; significantly n -Number & # 39; salmon and steel Snake River Basin. They believe, as do many scientists, that the violation will improve the Snake River salmon runs enough to lead to their recovery.
Violation: How much impact?
So, how much it will cost the breach to help the whales? Nobody can & # 39; & # 39 b says, certainty, but there are two scientific fields to compete with & # 39; which other Snake River chinook is more important whaling. Those who believe that the orcas are more dependent on the Chinook fallen from river basins Columbia and Snake tend to see less potential benefit from the breach, because the failure of & # 39; chinook runs it f & # 39; better shape than spring chinook runs. And most of the fall chinook returning to Dock & # 39; Columbia originating from the Snake River.
This is the side that has adopted the Fisheries Administration and National Oceanic Atmospheric Atmospheric, the responsible agency to oversee efforts to stabilize and recover both whales and fish. In fact sheet about the killer whale and the River dams Snake, the agency says falling Chinook done relatively well over the past decade, although their prospects declined in recent years due to conditions poor ocean.
"In the last decade, the salmon & # 39; adult chinook returned to past & # 39; Bonneville Dam on the Columbia River than in & # 39; any other time since the dam was completed in 1938. NOAA Fisheries found that Chinook open more than compensate for lost fish the dams in & # 39; terms & # 39; total number & # 39; chinook available killers whales, "the agency argues in factsheet.
The agency looks at all Dock & # 39; Colombia as a place that is already making its part in feeding & # 39; whales and hopes to see further improvements from other basins.
"The Columbia rivers and Snake are producing more than half of the Chinook on the West Coast. This is a place where whales because the salmon are here, not because they are missing," said Michael Milstein, spokesman for NOAA f & # 39; Portland.
Milstein said that it is important to work on all the stocks in which the whales eat.
"They all contribute fish for whales in & # 39; at different times of the year & # 39; different places," he said. "It's not about river is critical. It is about the river diversity and producing stocks, each with history and time of her own life."
Those who see the Chinook spring from the colony and basin & # 39; Snake as most tend to think that break can & # 39; play a significant role. Spring Chinook are less robust than fall Chinook, and laying in the greater Columbia Basin are dominated by the Snake River stocks. The breach dams can & # 39; potentially help the Spring Chinook f & # 39; a greater level of fall chinook, although a & # 39; beneficial for both runs.
ORKLI: specialists & # 39; Chinook
One thing is certain, the whales are resident in South Chinook salmon specialists. Constitute the majority of all fish diet, and whales are not enough to eat. To determine how to reverse & # 39; behind that, scientists of & # 39; NOAA tried to measure the relative importance of & # 39; & # 39 different cycles; Western Chinook salmon so they know where best to focus their efforts. In the ranking, scientists looked at three factors: if a stock looks in whale diet; if seen in whale diet during stressful winter months; and to what extent the stock enters time and space with whales during the year.
Based on this system, fall chinook from the Columbia Basin, including the Snake River Chinook falling, ranked relatively high – No. 3 on the list. This is mainly due to fall chinook are available for whale for most of the year. Resident killer whales in the South they are eating on the fallen Chinook during their forays wide off the West Coast roughly from last fall until May.
On the other hand, the spring Chinook orcas are less available for most of the time the whales are out of what scientists call the "external coast". However, since the spring chinook spawning in return to & # 39; freshwater, fish meet & # 39; or near the stage. It's a short window for whales, but some believe because of the density of fish in & # 39; at that time, a source & # 39; important food.
"The behavior of the drop stocks tends to be more coastal distribution of the ocean are more accessible to the whales for a longer period & # 39; time, not just during the migration generation", said Mike Ford, the conservation biology division director at & # 39; in November.
"As stocks led by spring, especially inside (runs) from the Snake and Columbia of & # 39; on, the distribution of their ocean not properly appear with nothing whales, except for that period a & # 39; a couple months when they return to spawn, "Ford said. "During that period, they can be quite important for the whales."
When scientists were covered health of Chinook runs and whale health, found that over the years clearly good straps, whale had higher rates of & # 39; birth. In fact, from 2013 to 2015, "there was a sharp increase in child", said Ford.
Ole Shelton, research ecologist in Fisheries Science at Northwest & # 39; & # 39 at NOAA, Seattle, said that there are more scientists do not know then how to create specific stocks & # 39; Chinook and southern residents. He call upon him "very active area & # 39; research".
But Shelton said that scientists know much more about the fall Chinook goes when it comes to distribution of their ocean to know about spring.
"The fall chinook tend to be closer to the coast, and tend to be more south than their victorious counterparts & # 39; Chinook f & # 39; particular area. Looking at distribution of fall chinook from Snake river, they tend to be slightly north of the river mouth, in the area & # 39; Vancouver Island and central British Columbia and outside coast & # 39; Washington. "the Chinook spring are much looked bad, but the general idea is that they tend to go away from the coast and & # 39; far north" .
Spring Chinook: evaluate the importance
Two of the three Puget pods of whales Sound to kill move to the Chinook spring when the fish stage near the mouth of the River Columbia in & # 39; March as fish prepare to enter a & # 39; fresh water generation.
"I think it is entirely reasonable that the River spring Snake receive tends to be seen as a likely candidate to be important during this time of year. They are almost certainly not those two other times important year , "said Shelton. "For that time of the year – winter and spring – says the winner of the Snake River chinook x & # 39; is likely to increase substantially higher than other stocks, but if you look at the whole year are just come. We are quite certain not f & # 39; Puget Sound, the Strait & # 39; Juan de Fuca and the Strait of Georgia. "
The importance spring is not conclusive, he said.
"I can & # 39; I strongly believe if the stream & # 39; Snake River chinook, though there are many more of them, would b & # 39; her health for the population (the killer whale). I & # 39; also see a scenario is not true. The better you do as you & # 39; for & # 39 stocks as you can, and be successful on this, "he said.
For Sam Wasser, professor & # 39; research in conservation biology, ecology and physiology at the University & # 39; Washington, m & # 39; there is no doubt that the Snake River Chinook are an important and even critical whaling. Wasser studied blood hormone found in the feces of whales among other things indicate pregnancy rates and levels & # 39; stress. His team used a new approach to collect whale feces. They followed after whales in boats and used specially trained dogs to light and track whale feces so they can be collected from the surface & # 39; ocean with a swimming pool cleaning nets, before separated or dissolved.
It found that 69 percent of all pregnancies can & # 39; located among the southern population of whales & # 39; killers failed, and more than 30 percent fell late in the term or little or shortly after birth when maternal risk is much higher. The stress from lack of & # 39; & # 39 x food, was likely the reason for failures, Wasser said.
He and others have measured two hormones in whale indicating stress. They found that when the whales return to the Salish Sea in the spring after eating at Columbia River mouth, the whale showed hypotension. But that quickly changed, x & # 39; probably because of the Fraser River Chinook is scarce in the Salish Sea until mid-August to mid-August.
He said winter when the whales are hunting off the coast of & # 39; the United States and Canada is a stressful time for them.
"This is a time not much worked for them. It's cold, should govern thermally, are not big salmon adults to go to the mouth & # 39; river, have all sizes & # 39; fish are harder to capture. "
After the winter, the whales get fleeting bounty & # 39; & # 39 in food, mid-spring end when targeting the spring Chinook bound for wind & # 39; Snake and Columbia. The Chinook stocks in the spring to push the more air & # 39; away are usually the first to show. They also tend to have content & # 39; to support higher fat by pushing & # 39; above. The Snake River Chinook dominate the Spring Chinook still returning from Dock & # 39; Columbia.
"The early start & # 39; Columbia River chinook are some known fattiest salmon," said Wasser. "That race was great. It was something that our work suggested was, very very important to re & # 39; filled (whale) from harsh winter and keep them until the River Chinook peaks Fraser move & # 39; away, not until mid-August.
Because the Chinook linked & # 39; places like Clearwater and Salmon rivers s & # 39; to go now, have evolved to be larger and more salt than other spring Chinook.
"They go around 900 miles in migration. They come with & # 39; loaded and early fat," said Wasser. "It is very, very crucial for these whales. It seems as if one run is critical, it can do something dramatic (a), is the Columbia River Chinook."
That is why many people look to breach pole as something that can & # 39; help the whales. Many whale advocates see as a potential quick fixes. Wasser is not among them.
"It ngħidx to just break the dams immediately," he said. "I think this is something that really deserves serious study, and until now, each time to bring that issue, saying that we can not go there. I think that needs to be investigated b & # 39; very seriously to see if there long-term solution. I reiterate long-& # 39; time. There are many things we can do in the interim. "
Barker can & # 39; [email protected] or be contacted at (208) 848-2273. Follow him on Twitter @ezebarker.
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