Today the returning numbers of adult salmon on the Columbia River have dwindled to less than six percent of historic levels.
I TIDE
T WOULD BE HARD to imagine raising your child without proper food, care and nutrition. Yet when it comes to our fisheries in the Pacific Northwest, we somehow expect baby salmon to grow up in such an environment without proper nutrition.
Common sense dictates that food is an important element to the survival of any fish species. Take, for example, any species of fish being raised in a hatch- ery. Have you ever seen a successful hatchery operation where the baby fish were not fed? One could make the argu- ment that outside of a healthy and con-
sistent water source, nutrients are the single most important factor to keeping hatchery fish alive — and healthy.
UNIQUE LIFE HISTORY
Pacific salmon have developed a unique life history trait that allows them only one chance to successfully spawn in their natal stream — then they die. The young salmon, called fry, grow in freshwater creeks streams or rivers and as smolts migrate to the ocean — transitioning from fresh to salt water during the arduous journey — to mature to adulthood.
www.joincca.org
Imagine the Columbia River in the early 1800s. Historically this river had annual salmon returns estimated at 16 to 20 million adults (much larger by some estimates). As those adults spawned and died, the tributaries of the mighty Columbia River were cov- ered with decaying salmon carcasses, which in turn fed populations of baby fish. This is nature’s way of transport- ing the nutrients from the ocean to the stream to support the salmon lifecycle. Except in the rarest of circumstan- ces, our Northwest rivers are no longer covered with decaying salmon carcasses. Today the returning numbers of adult salmon on the Columbia River have dwindled to less than six percent of his- toric levels. This is the case for most rivers, streams and creeks from Washington to Canada. As such, the diminishing returns of salmon have created a nutrient deficit, depriving baby salmon of an integral food source and depriving our local watersheds of essential nutrients — nitrogen, phos- phorus and carbon. Compounding the problem, rivers in western Washington and Oregon are especially prone to nutrient deficiency due to floods, gradient and loss of reten- tion capacity. Floods flush the rivers several times per year and remove nutrient sources such as leaves, trees, salmon carcasses and aquatic insects.
SCIENTIFIC BENEFITS
Numerous scientific studies have shown that the presence of salmon car- casses directly relates to increased sur- vival for juvenile salmon. When a car- cass deteriorates, pieces of flesh and eggs are directly consumed by juvenile salmon. One study that monitored the stomach contents of juvenile salmon
17
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64