Sunday, June 16, 2013

American shad: Invading the West

By Patrick Cooney

The disconnect of East and West was no longer so vast with the driving of the Golden Spike on the United States Transcontinental Railroad on May 10, 1869. Seth Green, an entrepreneur who is often credited with the invention of the fish reel, saw a golden opportunity to expand his empire with the presence of a cross continent railroad, but are we still paying the cost today of his ambitious ways?

American shad (Photo: Cooney)
As human populations swelled in the new world, wild stocks of fish were becoming more strained to meet the increased demand. In 1864 Seth Green developed the first fish hatchery in the Western Hemisphere raising salmon, helping to fill an increased number of hungry mouths. As he honed his techniques in Rochester, New York, he continued to add species to his aquaculture endeavors including American shad and trout.  Like any true entrepreneur, he looked to expand even farther.

At the time, very little caution or care was given to introducing non-native species of fish to new water bodies, and to be honest, many government agencies are still in the business today (European brown trout are a prime example). Seth Green wanted to expand his fish empire and he concocted a plan to introduce American shad, native to the Atlantic Ocean, to the Pacific Ocean.

Mr. Green outfitted a train car with milk jugs, a popular method of small fish transportation that would continue in popularity for another 100 years, and hooked up with the Transcontinental Railroad in 1871. A total of 10,000 American shad were dumped into the Sacramento River in Northern California, the fish survived, and then successfully spread along the entire Pacific Coast of the United States and Canada.

Salmon and shad in the counting window
Fast forward to today…literally today. More than 200,000 American shad (direct descendants of those initial 10,000) will swim through the Bonneville Dam fish ladders on the Columbia River today (6/17/2013) in their yearly migration upriver to spawn. These numbers are highly accurate because people are paid to sit in a small underwater room and count fish as they go by a small window (see link at end of story).

These people are held to the task every year of monitoring the populations of fish that return from the sea to spawn in the Columbia River. The effort started out with counting just salmon, but starting in 1946, American shad were included in that count, with a total of 20,279. Numbers steadily rose, until a peak was hit in 2004, when more than 5 million shad passed by the window, with a 15 year average of more than 3 million.

Shad anglers at Bonneville Dam.
American shad fishing is a big deal when there are that many fish in one spot at one time. To be honest, it is more like combat fishing as people crowd into tight areas where fish school at the base of the Bonneville Dam. I find it impressively ironic that most of these anglers do not know who Seth Green is, yet they are using a reel that was initially invented by Seth Green to haul in a fish that is a direct descendant of one introduced by Seth Green. With American shad being so plentiful in the Columbia, there are no catch limits, further increasing the frenzy of folks who flock to the area.


The Columbia River Gorge, shad angling boats,
and BonnevilleDam. (Photo: Cooney)


Back on the East Coast in rivers like the Roanoke on the North Carolina and Virginia border, strict harvest limits are currently in place, and scientists are working hard to estimate the run size of American shad to insure the long term viability of the population. Estimates of run sizes in the 1890s in the Roanoke River exceed 2 million American shad (similar to the total current run size in the Columbia River), whereas estimates from recent years in the Roanoke River show a population of ~10,000 American shad (estimates range from ~5,000 to ~30,000). Amazingly, one could watch the window on the Bonneville Dam on the Columbia for only an hour or two today and see what would represent the entire population from the Roanoke for the whole year.

Some interesting questions to consider with American shad:
What impact does the increasing number of American shad in the Columbia River have on struggling salmon populations?
Why are native populations of American shad continuing to struggle on the East Coast of the United States, while those out West that are introduced are thriving?
What are the long term impacts of non-native fish introductions?

Bonneville fish counting window live stream

9 comments:

  1. I caught my first American Shad on the Neuse River in NC this year. There really isn't that many that make it up to the Raleigh area or even the Tarboro area via the Tar River. The biologists seem happy with the numbers they surveyed this year but in my mind they are very low. They'd survey under 100 fish near Raleigh ever time. I've heard in the years past you could almost walk along the backs of the shad there were so many in the water.

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    1. Kevin, I think the Wildlife Commission biologists in your area are pleased to see steady numbers of shad, rather than declining, but overall they would love to see more in the river (give them a call and ask them some questions. They are great guys and have a wealth of knowledge. A great friend and former classmate of mine from 10 years ago, Kevin Dockendorf, is the research coordinator in your area, and he has an extremely extensive knowledge of the shad in North Carolina). I have caught many shad up in Fishing Creek, not far from your neck of the woods, and caught some in the Neuse River near highway 64 in Raleigh, and would agree that it would be amazing to see more. One must remember that the dams out here in the West have fish ladders to allow these fish to pass, whereas there is not that ability in North Carolina, preventing these fish from reaching their historic spawning grounds. In the end, this will continue to keep their numbers below historic levels. Check out the Pee Dee River below Blewett Falls Dam for an incredible American shad fishery!

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  2. In response to the 2nd question. Everyone loves the West Coast better. On a serious note, it is interesting that they should thrive so well in a non-native environment. There's no such thing as a free lunch though - cause for a raised eyebrow at the very least. Good article.

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    1. Sean Janson, you are correct, no such thing as a free lunch, unless you are buying! On a serious note, introductions of organisms into foreign environments is always a major risk. Without the presence of natural limitations or predators, the outcome could result in negative consequences.

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  3. That's really cool that you made that connection. I love to connect angling, history and our socio-economic issues but, this is one I wouldn't have made. Do you think that any fishing holes will ever get so used to invasive species that they just become the normal? What would happen if we removed those from their habitat? In retrospect it sucks to know that putting a few Asian carp here or there was the cause of a lot of these problems, but really who knew? Right now, the best we can do is to support our local habitats and continue to encourage the removal of select invasive species.

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    1. Sean-Scott, I am glad you enjoyed the article. Let me know if there are any topics that are of interest to you.

      As for invasives 'becoming normal', I do believe a new equilibrium will be achieved, but it will never be the same as before. Just as organisms evolve to given environmental conditions, environments also will evolve to the conditions that are presented to them.

      If we removed these organisms, the ecological damage already done, may be irreversible, but if taken care of soon enough, could be restored to more historic state.

      And yes, Asian carp are a difficult topic, as it appears that these fish were introduced during a flood when they escaped a fish farm. With this in mind, it might be best to not only consider those that are purposely released, but also those with the distinct possibly of release in flood prone areas.

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  4. Kevin, Sean, and Sean-Scott, thank you for the comments. One of the major goals of this site is to create conversation and discussion. You have all done just that, so thank you.

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  5. I wonder about the fish passage on the east coast. Lots of time money and research has gone into maying fish passage on dams in the columbia as fish friendly as possible (they are still dams unfortunately) whereas I'm not sure the same has been done on the east coast.

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  6. do you get paid for catching Shad on the Columbia river oregon / washington

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