while this meeting of fresh and salt is necessary, juvenile salmon use estuaries for more than a place of adaption. Eelgrass and further vegetation tend to grow in or around these shoreline areas, offering protection for juvenile salmon from predators such as larger, grown salmon. Furthermore, "juvenile salmon experience the highest growth rates of their lives while in estuaries and nearshore waters". Since nutrients are so crucial to their growth, the complex food web produced from these water plants such as eelgrass serves the juvenile salmon well, and these salmon tend to be more selective, using instincts to tell them what will better prepare their bodies for ocean residence or migration later in their lives. Habitat loss Although salmon spend only a part of their life cycle in near-shore areas, these habitats are critical to the survival of salmon populations. Shoreline habitats of Puget Sound have suffered significant losses over the last 125 years. When marshes are lost, young salmon lose food and shelter. Studies show a 73 percent decline in salt marsh habitats bordering Puget Sound. Nearly all salt marsh habitats within major urban areas along Puget Sound have been destroyed. The Puyallup River Delta, for example, lost 100 percent of its nearshore habitat. Other factors that contribute to habitat loss are pollutants, bulkheads, loss of shoreline vegetation and the blockage from docks and piers. Polluted estuaries and nearshore areas have caused juvenile salmon to suffer adverse effects as they pass through the estuaries. Human-caused stresses can cause immune dysfunction, increased susceptibility to disease, and impaired growth. Bulkheads can disrupt shore drift and shoreline vegetation, thus eliminating cover and food sources for young salmon. Loss of shoreline vegetation along the shore is of particular importance to juvenile salmon because it stabilizes the shoreline, provides shade, acts as a protective cover, organic input and food source for young salmon moving in close to shore. The decrease in riparian vegetation along the shoreline can also account for an increase in stream temperature, which can benefit invasive species of bacteria and parasites that are harmful to the salmon. There are also concerns over hatchery spawned salmon that are capable of spreading diseases to wild populations of juvenile salmon. These wild spawns are not able to fight off these illnesses that the hatchery fish are given antibiotics for, which can also drop wild spawn rates. Arguments can also be made that while hatcheries