Dating salmon postcards
The oldest known North American date nail is a 97 from the Mississippi River & Bonne Terre.
It was in 1899 that major railroads began using nails to date ties with nails ... It peaked in the early 1930s with over a hundred different railroads using date nails in 1931.
In many river systems, hatcheries are necessary to maintain populations.The trend was most pronounced in populations from Alaska’s once-legendary salmon-producing rivers, such as the Kenai, Kuskokwim and Yukon, where salmon are born before migrating to the ocean and then returning at the end of their life to spawn.Although the study didn’t formally test why the largest Chinook salmon are disappearing, the authors – after considering other possibilities, such as climate change and competition between different species of salmon – believe growing populations of resident orcas in the salmon’s northern feeding ground are the most plausible cause.Meanwhile, salmon size and age have decreased at the same time as fishing restrictions have tightened and reduced the overall harvest, which would seem to rule out fishers as a factor.The study itself drew no clear conclusions, however.