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Date Posted: 03:05:48 05/23/13 Thu
Author: Don Johnson
Subject: Where Have All The King Salmon and Beluga Whales Gone? Part 1
Where Have All The King Salmon and Beluga Whales Gone?
Are you concerned about where all our king salmon and Beluga Whales have gone? Have you been listening to the great many people attempting to convince you
that the reasons for our missing king salmon and belugas are mysteriously lurking out there somewhere but can't be precisely located? The reasons for this missing
marine life is simpler than some would have you understand. If you would like an instant explanation on king salmon, here is how you may get it.
When you encounter your next Alaska fisheries management person, try asking them the following basic question. What does it take to build a juvenal king salmon in the ocean?
You will no doubt be shocked when you hear the response because most of these fisheries management people have no idea what it takes to build a king salmon in the ocean.
If you are lucky you may get a response like "feed them a bunch of herring, sand lances or something else". Your average ADF&G fisheries manager has great knowledge
regarding what it takes to keep fisheries user groups happy but they will display very little knowledge regarding what it takes for our ocean to generate a king salmon.
This lack of ADF&G ocean concern for our king salmon is a large part of the reason why we are currently seeing fewer and fewer king salmon.
The correct answer to the above question is "a great many crab larvae" because that is precisely what juvenal king salmon exclusively require to get them to where they
are finally able to begin feeding on larger prey like herring or capelin (small fish). Unfortunately sockeye salmon also feed exclusively on these same crab larvae.
It is even more unfortunate that these sockeye exclusively feed on extremely young crab larvae, which are less than 5 mm in size. It is even more unfortunate that
juvenal king salmon happen to exclusively feed on older crab larvae which are greater than 17 mm in size. Are you beginning to see the conflict which is so mysterious?
The mystery becomes clear when you begin to understand that our ocean is currently producing about 1% of what it used to produce of these >17 mm crab larvae.
What would happen if you increased sockeye stocks by many millions of additional fish, while maintaining king salmon stock levels? The out come is predictable.
It would be like viewing a group of people lining up to a cafeteria for lunch and suddenly a mob of rowdy line cutters jump in front of the group and get themselves
served first. In this "marine cafeteria" the rowdy mob are sockeye salmon and they are basically line cutting our king salmon. As our ADF&G manage our fisheries to greatly
expand (only sockeye stocks) more and more line cutting sockeyes displace more and more juvenal kings, until kings are actually being pushed backward away from
where the food is located. The situation is much more complex than what is described here but this is a basic explanation as to where many of our king salmon
have gone. Deep within our ocean food web, king salmon are being substantially displaced by sockeye salmon. There are many other issues involved like king by-catch
within commercial pollock and salmon fisheries and our decreasing ocean nutrient levels but how do you address them if juvenal kings are being starved to death?
If you would like to read a more detailed explanation it is located at http://www.voy.com/177140/152.html?z=1
Our Alaskan marine ecosystems are suffering from a loss of biodiversity due to the destruction of our marine food chains and habitats.
ALASKA'S ONCE GREAT SALMON RUNS
Many people are asking where our once great populations of king salmon have gone. Few people have any idea what may have happened to these once great salmon runs but if you ask the Alaska Department of Fish & Game they will announce a new catch-all term called (Lack Of King Salmon Abundance). This term is offered in an attempt to convince the public that there isn't a real known cause for the missing salmon. The ADF&G would prefer that you believe abundance issues are like "the rain falling out of the sky", uncontrollable and therefore you take what you get. I cannot agree with this alleged Lack Of Abundance Theory. There are known causes for Lack Of Abundance Issues but along with identifying a problem like this you need to also locate the possible causes of the problem. Our ADF&G has identified a (Lack Of King Abundance Problem) but are unable to locate the possible causes of that problem. It is my purpose to list possible reasons Alaska is currently seeing fewer and smaller king salmon, silver salmon and halibut today than observed historically.
THE DIFFERENCES BETWEEN KING & SOCKEYE SALMON
The king salmon abundance issue begins with a simple and very practical question. Why the dramatic difference between king and sockeye salmon abundance in Cook Inlet? Cook Inlet annually produces a high abundance of sockeye salmon along with a low abundance of king salmon. Since these salmon migrate side-by-side there is a reasonable assumption that our king salmon problems may not be happening while kings and sockeyes migrate together. This is assumable because in general what happens to one stock would logically happen to the other. Sockeyes are more prolific than kings therefore you would expect kings to recover slower from a marine disaster or commercial over-harvest but in general both stocks should respond in the same direction regarding food chain issues. Commercial and public fisheries have been both impacting our king salmon stocks for many years. Commercial activities have had the dominate impact on these fisheries but that impact has been happening for many years, while we have not observed today's kind of dramatic king salmon decreases. This abundance of sockeyes and lack of kings says that different factors must be impacting these salmon at sea. King and sockeye salmon feed on different foods while as sea so this king salmon problem appears to be directing our attentions towards a problem within the marine food chain.
KING AND SOCKEYE SALMON OCEAN FEEDING
To explore this possible marine food chain problem, the differences between king and sockeye salmon need to be investigated. King and sockeye salmon have many things in common along with some significant differences when it comes to how they live and feed. To find the differences you need to investigate what these salmon feed on. King and sockeye salmon both begin feeding on much the same things. Both salmon begin their lives by feeding on zooplankton like euphausiids (crab larvae). Juvenal kings feed on euphausiids until they reach about (16 inches) in length but these older euphausiids need to be greater than 17 mm in size. Sockeyes feed on younger euphausiids which are less than 5 mm in sizes. After juvenal kings reach (16 inches) they begin exclusively feeding on things which eat plankton like euphausiids, herring and capelin. Adult kings salmon diets switch to things like herring, capelin (small fish), sand lances, pollock and lanterfish. Sockeye however continue feeding mainly on very small (3-5 mm) plankton and zooplankton like euphausiids, while juvenal kings are feeding mainly on (>17 mm, greater than) euphausiids. After reaching (16 inches) kings make a feeding shift to herring and capelin. It is this king salmon dietary leap which allows kings to then grow to their much greater size. These king salmon feeding characteristics then become the focus of this investigation.
With sockeye salmon exclusively feeding on (3-5 mm) euphausiids and juvenal king salmon exclusively feeding on (>17 mm) euphausiids, one may assume a lack of feeding conflict. Unfortunately a conflict can be created when fisheries managements manipulate stock numbers. As the fisheries managers begins to manage for (only maximum sockeye production), this action can set into motion an unusual but intense feeding factor within our ocean. This sockeye feeding factor then specifically targets (3-5 mm T. spinifera, euphausiids 'crab larva'). These are in fact the same crab larva which juvenal king salmon will seek out later but after they have reach a length greater than 17 mm . Juvenal kings less than 16 inches in length need euphausiids greater than 17 mm in length OR THEY WILL STARVE TO DEATH. This is the primary marine feed these juvenal kings survive on during this early time in their life. The unfortunate part is that when sockeye salmon populations are expanded enough by fisheries managers, they begin to operate as a supreme feeding machine along with billions of pollock living in the same waters. Together these vastly superior numbers of (small crab larvae feeders) then sweep the ocean for all euphausiid larva near the (3-5 mm) length, thus leaving little (if any) larva to grow larger for juvenal king salmon to feed on while building reserves to allow them to make their jump to feeding on herring or capelin. Because this strategic (>17 mm) euphausiid elements is therefore missing, many of these juvenal king salmon then (starve to death) and therefore never become adults. 95% of a sockeye salmons diet focuses on these young 3-5 mm T. spinifera, euphausiids. 95% of a juvenal king salmon's diet focuses on the older (>17 mm) euphausiids after they have managed to escape massive sockeye and pollock feedings. King salmons diets eventually switch over to small fish but the question is how do these juvenal kings get to that switch-over point if they cannot forage enough crab larva larger than 17 mm, so they may become adults? Our latest marine science's are now showing a dramatic reduction in the North Pacific marine production crab larva. This science is telling us that we are now seeing that our (>17 mm) production of euphausiids is currently about 1% of what it used to be historically. We still have good production levels of smaller (3-5 mm) euphausiids, which are feeding our sockeye and pollock resource but 99% of the main diet of juvenal king salmon is now completely missing. Everyone should display shock when they hear that an element like this has gone missing within our marine environment. Our ADF&G is not showing shock, they are claiming that our missing kings are part of our natuarl marine cycles, "like rain falling from the sky".
These fisheries mangers continue to manage our fisheries as if we still have sufficient euphausiid resources to feed our current juvenal king salmon. Because these mangers do not understand the needs of our juvenal kings, they then claim that the resulting lack of returning adult kings salmon is a "natural" Lack Of King Salmon Abundance. There is nothing "natural" about this Lack Of King Salmon. If you follow the bread crumbs you find them leading back to a lack of (greater than 17 mm crab larva), and that lack is the direct results of fisheries mis-management. If we just assume that these juvenal kings somehow find enough (>17 mm crab larva) to survive on into adulthood, then you must consider their chances of finding enough herring or capelin to survive on as adults. Unfortunately these smaller fish also feed exclusively on the same (>17 mm T. spinifera, euphausiids) and because we now only have about 1% of what we used to have in euphausiids, these small fish are also now faced with the same dramatic lack of feed like juvenal king salmon. This dramatic lack of adequately sized marine food then demands closer examination. That examination needs to focus on the ocean production of plankton, zooplankton, euphausiids, herring, capelin and juvenal kings.
NOAA Technical Memorandum NMFS F/NWC-91, Salmon Stomach Contents, From the Alaska Troll Logbook Program 1977-84, By Bruce L. Wing , October 1985. Type, Quantity, And Size Of Food Of Pacific Salmon (Oncorhynchus) In The Strait Of Juan De Fuca, British Columbia, Terry D. Beachami.
PLANKTON, PHYTOPLANKTON AND ZOOPLANKTON LIKE CRAB LARVAE
Our North Pacific marine food chain begins with (plankton). These plankton drift with ocean currents because most of them cannot swim. The name plankton comes from the Latin term for (wanderer). Phytoplankton are single celled organisms which absorb energy from the sun and diatoms from the water as they retain carbon to fuel their survival. That carbon then plays a fundamental part within the (carbon cycle) as it and the (oxygen cycle) work together to produce about half of the oxygen we breath everyday. This oxygen results from photosynthesis actions between ocean nutrients like nitrogen and phosphorus. Plankton live within these cycles expelling oxygen, absorbing carbon, dying and then sinking to the bottom of our oceans. This results in a planet-wide cycle which removes millions of tons of carbon from the atmosphere and replaces it with oxygen. This is an (Anti Global Warming) cycle. That is not all plankton do before they die; they also make up the foundation of our ocean marine food chain. Phytoplankton are then eaten by the more complex zooplankton animals which are marine life like euphausiids (crab larvae). At night, zooplankton like crab larvae sneak up to the surface and feed on phytoplankton in relative safely. Once these larvae's become adults they will go on to basically feed just about everything in our ocean with their resulting crab larvae. These zooplankton crab larvae then become the focus of this investigation as they live and feed within the phytoplankton.
Female crabs usually release their larvae during a spring high tide. They do this in an attempt to limit predation by everything but mainly salmon. As the tide peaks out the larvae swim to the surface and are carried away from the hatch site by the tide to the main ocean. As the tide reaches its low and starts to flood again, the larvae then swim towards the bottom, where the water moves slower. As the tide then again ebbs, the larvae swim to the surface and resume their journey to the ocean. This predator dodging procedure may take days or weeks but will eventually allow most of the larvae to reach the main ocean. These crab larvae are called meroplankton because they spend part of their life living and growing within the plankton after they exhaust the yolk sack they are carrying from the egg they hatched from. These crab larvae spend varying amounts of time within the plankton. That time may be minutes or over a year before graduating to their adult benthic (seabed) existence. These young crab rapidly adapt to a deep-water pressurized existence and cannot survive the upper parts of the water column. Life at this pressurized existence carries one atmosphere for every (10 meters) of water. Sunlight rarely penetrates these depths therefore the main energy source for these deep benthic ecosystems is most often dead and decaying matter like rotting salmon carcasses, which sink from the higher water column.
Immature crab larvae pass through a number of stages as they move from hatching to adult. Each crab will go through many molts as their very hard exoskeleton is shed away over and over to allow the crab to grow larger. If some how these crab larvae metamorphose (change to different physical form) too far from a suitable settlement site, they will perish. Once they locate a suitable site, these crab larvae will feed on plankton for several months, while molting many times. These larvae will then change their body forms over and over until they finally sink to the bottom and become the (non-swimmers) that live on the seafloor and look like crabs, but they are still smaller than a penny in size. Our fisheries managers need to determine where these crab settlements are, this will help us understand what ocean habitats encourage crab population growth and eventually locate which areas of Alaska's ocean bottom should be considered (essential habitat for crabs). In general it has been found that crabs prefer to settle on structurally complex substrate, such as algae or plant-like growths. Increased structures like this will increase the total number of suitable crab settlements
MARINE ENERGY / CRAB PRODUCTION
Crabs must molt their shells in order to grow but females crabs must also molt their shells in order to mate. These shell moltings require a huge amount of energy and that energy is expected to come from ocean nitrogen and phosphorus nutrient levels. While maturing, these crab will prey on a variety of things which include: sea urchins, snails brittle stars, worms, clams, mussels, other crabs, algae, sand dollars, barnacles, other crustaceans, fish, sponges, and sea stars. Adult crab and their larvae are directly affected by a decrease in ocean nitrogen, phosphorus and nutrient levels in general, but also indirectly when their prey also suffer from the same lack of nutrients. If these crab do not have sufficient nutrient rich waters they will not molt properly due to low nutrient energy levels. This will affect their maturing, growing and mating processes and result in the eventual death of the crab.
SALMON ESCAPEMENT, SPAWNING, DEATH, ROTTING, NUTRIENTS, PLANKTONS AND EUPHAUSIIDS PRODUCTION
One major way to increase the survival of all forms of plankton and therefore also crabs, is by allowing salmon to escape, spawn and die in their native fresh water rivers and streams. This is basic gardening 101 and can be directly applied to plankton and ocean crab production. The death and rotting of a salmon is as much a part of this cycle of life as any other part. Spawned-out salmon carcasses are a vital link between freshwater and saltwater marine ecosystems. Without these decomposing salmon carcasses it is impossible for nursery lakes to maintain adequate nutrient levels thus also causing the ocean they flow into to become nutrient impoverished. A nutrient impoverished ocean works to prevent increased phytoplankton, which works to prevent increased zooplankton like crabs. The reason for this connection is because young crabs feed on the phytoplankton, which is currently at a 50 year low in the North Pacific. Reduced salmon escapement levels have resulted in reduced biogenic fertilization, which has resulted in reduced juvenile and adult crabs. Phytoplankton enhancement is at least as important as sockeye enhancement but we see little to no ocean phytoplankton enhancement while millions of dollars are spent on sockeye enhancements. What is the purpose of spending millions of dollars on sockeye fisheries enhancement and nothing on what those millions of salmon are going to feed on? It is not coincidental that the North Pacific is currently at a 50 year low in king salmon, crab and herring production. It is also not a coincidence that Alaska has been escaping minimal numbers of salmon for about 50 years. The commercial removal of these salmon from our waters has resulted in dramatically lowering our ocean nitrogen, phosphorus and nutrient water ratio levels. The removal of these rotting salmon from our ocean waters has effectively removed the primary building blocks necessary for ocean planktons to build on within our marine food chain. This removal has resulted in our ocean waters becoming nutrient depleted and unable to produce maximum levels of planktons along with the resulting euphausiids, which would have fed all our herring, sea lions, salmon and whales.
NORTH PACIFIC COMMERCIAL CRAB OVER-HARVEST
It is shocking to discover that our North Pacific Ocean has 99% less euphausiids today (which are greater than 17 mm. in length) than we have had 50 years ago. This unfortunate fact quickly generates a desire to discover why these (>17 mm) euphausiids have disappeared from the North Pacific marine environment. A quick review of Alaska commercial crab fisheries harvest can shed much light on these missing euphausiids. Tanner crab peak commercial harvest was in 1978 and at 66.6 million pounds. In 1979 tanner crab populations (crashed) because of commercial over-harvest. By 1984 the commercial tanner harvest (crashed) again because of over-harvest and went down to just 1.2 million pounds annually. Both Bering Sea (tanner and snow crab stocks) were officially declared (crashed) and commercially over-harvested in 1999. This fishery went from 66 million pounds in 1978 to 22 million pounds in 2004 because of commercial over-harvest. (22 million is 33% of 66 million).
In 1980 Bering Sea, (red king crab) commercial harvests peaked at 130 million pounds. That commercial over-harvest then caused a red king crab (crash) from then on until today where we now expect about a 15 million pound harvest. (15 million is 11% of 130 million)
The North Pacific Fishery Management Council, National Marine Fisheries Service, and Alaska Department of Fish and Game came together and drafted a crab rebuilding plan in 2000, to try to clean up the over-harvest mess. Unfortunately these crab populations still refuse to rebound because they lack the necessary ocean nutrient energy levels to fuel a rebound.
The above commercial crab fisheries have crashed over and over until finally settling at annual harvest levels which are around 11% - 33% of what they used to be historically. Within all this commercial crab over-harvest, millions of undersized female crabs have been brought up as by-catch and thrown back into the ocean. Many of these female crabs die anyway and result in a great reduction in the total crab biomass. These crab have adapted to a deep-water pressured existence, when trapped by commercial fisheries and instantly jerked to the surface, many are not able to survive the nitrogen bubbles which buildup in their bodies. These crab therefore die unseen by anyone on the way back down to the bottom. With all this frenzied commercial activity taking place year after year, is it any wonder that in general Alaska crab populations are officially on the decline? With this commercial over-harvest fact finally realized, is it any wonder that we currently lack the euphausiids necessary to feed
our juvenal king salmon? The complete economic devastation of the commercial cab fishery may appear to be a sickening and fitting end to the wholesale over-harvest but that industry crash was like turning
on the lights and watching the bugs run away. The crab crash left millions of dollars worth of crab boats idle in port. The owners of these boat immediately began looking for another fishery to take advantage of. These owner either sold their vessels for about 25% of what they paid for them or they discovered Alaska's relatively untouched Pollock fishery. Most converted their boat to Pollock fishing and so began the great commercial Pollock over-harvest along with the massive king salmon by-catch that goes along with it.
So as we watch "The Deadliest Catch" on television, we now see the actual truth of just how deadly these commercial crab fisheries were. These commercial fisheries are not in the best interests of our marine eco-systems. They are also not in the best interest of the Alaskan public who expect the State of Alaska and the U.S. Federal Government to manage these marine resources in way which allows them to co-exist and not destroy each other. These fisheries are currently being mis-managed by the ADF&G and the U.S. Federal Government to promote only sockeye salmon and pollock production. This kind of unbalanced fisheries management has led to the soaring and crashing of many of our fisheries resources. Our marine ecosystems are suffering from a loss of biodiversity due to the destruction of our marine food chains and habitats.
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