Restoring herring and related species in Rhode Island rivers.

Restoring Herring in Rhode Island rivers

 

Restoring herring and related species in Rhode Island rivers. Greg GerrittDecember 2010

Daniel P. Jones in his book “The Economic and Social Transformation of Rural Rhode Island 1780-1850” refers numerous times to the process by which the industrialization of RI lead to the demise of fish runs and the effect of the ending of these runs on farmers and communities.  The damming and destruction of Rhode Island rivers and their fish runs cut off an important food source for Rhode Islanders, and helped erode the soil fertility in Rhode Island by cutting off the herring and related species that farmers in New England, from the earliest native inhabitants right up until the industrial revolution, had used to fertilize the soil. ( Everyone growing up in the Northeast has heard the tale of how the native people of Massachusetts taught the Pilgrims to put fish under the corn hills) Jones offers that the industrialists and merchants not only needed the water power for their mills, but that they were also aware that cutting off the fish would force farmers to either become commercial farmers and therefore customers, or to give up farming and work in the mills.  Interesting take on what it took to create an industrial economy.

I therefore find myself thinking that it is rather fitting that as we move through a post industrial economy in RI that restoring the fish runs has become part of the way forward.

With the mills no longer operating, it seems appropriate that Rhode Island rivers are reverting to places of life and sustenance, with and without our help. On previous occasions http://prosperityforri.org/?page_id=24 I have written on the relationship between ecological restoration , including restoring herring runs, and food security for Rhode Islanders, and on the importance of ecological restoration for our future prosperity  http://prosperityforri.org/?page_id=95.  We now have an opportunity to ground test such thoughts.

Rhode Island is embarked upon an exploration in restoration, the building of fish ladders and removal of dams in an effort to return spawning runs of anadromous fish, mostly those in the herring family including alewives and shad, to the rivers and streams that border Narragansett Bay and enter into the ocean from RI’s south shore. With modifications these fish passages can also serve the catadramous eels that breed in the Sargasso Sea and return as little glass elvers to grow and mature in the rivers and streams, but lets focus on the herring clan.

The premise is pretty simple.  A variety of fish in the herring family; American shad, alewife, blueback herrings live and feed in the ocean and breed in freshwater up rivers and streams all along the Atlantic shore. Each species has its own unique habitat requirements, but all of these fish create fairly similar anadromous migratory and breeding systems in the streams they inhabit.

 

http://www.edc.uri.edu/restoration/html/intro/fish.htm

“It has been determined by RIDEM that there are at least 41 streams in the Narragansett Bay watershed with potential for fish run restoration in Rhode Island and Massachusetts. Currently 18 streams support herring runs in Rhode Island but most are impaired to some degree and in need of restoration. Historically, at least 45 runs existed in the Narragansett Bay watershed. The most significant of these were the Taunton, Blackstone, Pawtuxet, and Ten Mile rivers.”

 

The various herring were extremely bountiful, with hundreds of thousands of fish returning in any given year to even small streams to breed.  The life cycle of these fish is that they are born in freshwater, move out to the ocean by fall of the first year, live in the ocean feeding for 4 or 5 years. Then the small percentage of the millions of babies born 5 years before that survives the 5 years in the ocean returns to rivers and streams to breed, create millions of baby fish, and start the cycle again.

Fish runs tend to be extremely variable from year to year. Weather, chemical spills, a bountiful crop or dearth of predators, and a myriad of other factors interact in ways we can not always predict.  The table listing the number of fish recorded in the various streams for each year (Chart 1) is used with the permission of RIDEM, who compiled the information. It was sent by RIDEM biologist Philip Edwards who was also very helpful in explaining the data and answering questions. The data shows the numbers vary tremendously from year to year.  But the overall trend throughout the western Atlantic is smaller runs and in 2006 RI banned the taking of herring in streams and rivers, joining our neighbors in doing so.

In response to my inquiry about herring run restoration Save The Bay’s Bay Keeper John Torgan  discussed the trend of smaller herring populations for runs that survived the industrial revolution..

There are a number of theories on reasons for the decline. The most likely, according to the Pew-funded Herring Alliancehttp://www.herringalliance.org/ , is that too many river herring are being captured at sea as by-catch in the Atlantic herring fishery. Other suggested reasons include climate change and shifts in predator-prey relationships.

Torgan did not note that the water is cleaner and the up river habitat better protected than it has been in 200 years, eliminating those as likely causes in the recent troubles for herring, but we all ought to take notice of that and rejoice as we restore wetlands and riverine forests even as we struggle with sprawl.

It appears that there is the opportunity to return an additional one million breeding fish each year to our waters if we open up to the returning fish a few of the larger streams and rivers such as the 10 Mile, Blackstone, Pawcatuck,  and Woonasquatucket rivers.  If we add in additional streams beyond where fish ladders and dam removals are already planned maybe we can have 2 million more fish moving into Rhode Island’s rivers each spring and 10’s of millions little ones flowing out to sea in the fall.

As a person who prioritizes food security and intuitively knows that healing ecosystems is going to add to our food security, it is interesting to ponder what 1 million extra fish in RI waters would do.  It would add one fish per year to the diet of each Rhode Islander if we caught all of them.  In other words it would do nothing to improve the food security of Rhode Islanders nor add materially to our diets.  We might catch a few more bluefish and stripers, and we would eat a few herring if the fishery was opened upon its general return to health. But one million more herring each year would be insignificant on its own in terms of feeding one million Rhode Islanders, though as part of a larger ecological restoration and local food agenda, it would be another piece of the puzzle. It should be noted that the last time locally caught river herring would have been a regular part of the diet in Rhode Island there were only 83000 people living in the state. (1820 Census)

As an ecological restoration and creator of further resilience in our rewilding systems, critical in an age of climate change, it may be much more significant.  1 million fish will not provide much sustenance to one million people, but it would feed osprey, bluefish, stripers, tuna, seals, whales, eagles, otters, herons, and dolphins. A system of 5 different year classes of fish populations falling from 50 million babies flowing out to sea to one million returning breeding adults 5 years later feeds a lot more piscivores than a system 5 year classes of 10 million babies falling to 200000 returnees in 5 years.

Just for laughs, ponder this. If the 400 osprey in RI eat 5 fish a day and osprey live in RI for 200 days a year,  that is 400,000 fish a year.  Marine mammals eat large numbers of fish,    Seals eat 10 lbs of fish per day.  400 seals intown for 150 days.  Eating 600,000 pounds of fish while in Narragansett Bay.   When new herring populations are added to what is already out there does it make it possible for seals to return to northern breeding sites in better shape? For osprey to fledge more young? Larger heron rookeries?

An extra million or two fish a year could make a big difference in the productivity of the ecosystem.  Reverberating up and down the ecosystem, not just for the top predators we pay attention to,  especially when we consider how much poop/ecosystem fertilizer that 1 million fish produce.   Even if we are not sure how much 1 million herring adds to our economy beyond more fishing days for recreational fishers, and more birds to see for birdwatchers, it does make us better off.

It is too soon to tell whether or not the recent spate of dam removals and fish ladders will have the desired effect of increased fish runs.  It will take 5 years for the first years babies to return, and none of the recent projects in Rhode Island has been in place for 5 years yet. We expect fish runs to improve, they have elsewhere when this type of restoration effort was made.  But if the hypothesis that overfishing in the ocean is what is diminishing runs is correct, adding and restoring habitat in the rivers may help a bit but the effect is likely to be overwhelmed by the overfishing,   We hope the oceanic issues can be addressed, and that the fish runs return in a big way, but even without these specific fish runs both the local ecology and the community receive benefits.

Tom Ardito of the Narragansett Bay Estuary Program points out:
“ I see the real benefits of dam removal as restoring historic connectivity and both physical and riverine ecological processes–more natural flood plain processes, sediment transport, flow velocities, stream temperature, etc., in addition to passage for a wide range of creatures, in the water and along the banks.  Ladders restore a much more narrow range of functions–typically passage for target spp. only (herring and shad, maybe eels, sea-run trout, etc.)–and even that, under a limited flow range– and I think almost any ecologist would say that dam removal is greatly preferred.  That said, a ladder is a big deal on a system like the Blackstone, where we’re trying to reconcile industrial and ecological uses in a pretty innovative way. “

Christopher J Fox, Executive Director of the Wood Pawcatuck Watershed Association offered his comments on the same topic;

“Unlike so many of my colleagues, I know little about fresh water fish. I would have to say that WPWA’s efforts to restore fish passage on the Pawcatuck serves the broader interest that is River Connectivity for wildlife and people.  Frankly, we use fish passage funds and interest to further this broader goal.  That is why we are so motivated to remove dams rather than build fish ladders.  Unlike our counterparts on other rivers, we are in a better position to remove dams and look to ladders as a last option because the Pawcatuck dams are so small.  I take a more “if you unbuild it, they will come” approach to fish passage.  After a removal, if the fish never come, we have removed a significant road block to ALL the species that rely on the riverine environment.  Removing the dam also helps out the recreational boater by (in many cases) removing a portage from their paddle.”

We do not have any answers yet.  We do not know how well we can restore Rhode Island’s herring runs amongst the ecological ruins of the 21st century. Will climate change, toxic chemicals, and overfishing prevail?  Has the ecological space and food supplies in the rivers diminished to the point where it can not be resurrected?

What will success look like?  Would we notice a trend towards more osprey and seals and understand it?  Will herring end up on people’s plates again or in their compost piles and help cycle some of the marine productivity on to the land as our predecessors did?  Will they be toxin free enough to eat? Will we have the pleasure of watching herring swimming up rivers to places they have not been in 200 years? Or shall we just have better river function and connectivity including less damaging floods?

 

Baykeeper John Torgan notes
Whatever the reason for the decline, providing for fish passage is now more important than ever,  and it is one of the best things people can do to save these ancient and irreplaceable fish runs.

 

 

 

I am with John. Restoring our local ecosystems is one of the most useful things we can do as we face climate change, rising sea levels, and the long term greening of our economy. Every penny spent on restoring rivers will come back to our communities many fold whether the fish multiply or not.But I am really looking forward to watching the herring return in the spring.

 

 

 

Chart 1 Alosid Fish returning to selected RI waters Provided by RIDEM

 

Gilbert Stuart Nonquit Buckeye Brook Woonasquatucket-RS Hunt-Forge Rd Pawcatuck River
Year Alewives Year Alewives Year Alewives Year Alewives Year Alewives Year A. shad

1979

5

1980

165

1981

64,297

1981

882

1982

88,194

1982

644

1983

68,919

1983

491

1984

17,337

1984

2,163

1985

16,492

1985

4,219

1986

48,011

1986

3,000

1987

50,893

1987

724

1988

74,324

1988

580

1989

89,577

1989

533

1990

11,009

1990

904

1991

21,540

1991

1,900

1992

32,384

1992

2,119

1993

21,754

1993

797

1994

43,342

1994

270

1995

95,331

1995

740

1996

70,904

1996

1,508

1997

122,720

1997

2,061

1998

262,315

1998

936

1999

259,336

1999

230,853

1999

2,149

2000

290,814

2000

185,524

2000

608

2001

254,948

2001

129,518

2001

774

2002

152,056

2002

97,444

2002

768

2003

67,172

2003

74,998

2003

38,949

2003

243

2004

15,376

2004

25,417

2004

5,010

2004

301

2005

7,776

2005

42,192

2005

18,707

2005

151

2006

21,744

2006

74,902

2006

9,428

2006

92

2007

36,864

2007

59,380

2007

18,587

2007

44

2008

58,640

2008

224,506

2008

34,629

2008

70

2009

34,835

2009

49,841

2009

31,697

2009

69

2010

110,287

2010

38,516

2010

8,299

2010

25,618

2010

3,005

2010

44

 

 

 

 

 

 

 

 

Hunt-Forge Rd Pawcatuck River
Year Alewives Year A. shad

1979

5

1980

165

1981

882

1982

644

1983

491

1984

2,163

1985

4,219

1986

3,000

1987

724

1988

580

1989

533

1990

904

1991

1,900

1992

2,119

1993

797

1994

270

1995

740

1996

1,508

1997

2,061

1998

936

1999

2,149

2000

608

2001

774

2002

768

2003

243

2004

301

2005

151

2006

92

2007

44

2008

70

2009

69

2010

3,005

2010

44

 

 

One thought on “Restoring herring and related species in Rhode Island rivers.

  1. Very interesting article.
    One caution, though. Discussing the impact of restoring “one million herring” to RI waters leads to much confusion, as can be seen, for example, here: http://www.ecori.org/natural-resources/2013/9/15/the-river-runs-through-it-without-interruption.html

    Most (including, apparently, EcoRI) don’t realize that the overwhelming numbers of herring in RI waters are not “river herring” (blue back and alewife), but atlantic herring, a non-anadromous fish totally unrelated to to the above, with totally different life cycle, which do not spawn in rivers, but spawn deep offshore. The predators you mention are feeding on atlantic herring, not river herring (excepting osprey sometimes). And none distinguish between atlantic and river herring when feeding.
    The only predator of note “feeding” on the river herring now is humans, which, ironically, are targeting atlantic herring offshore, but picking up some small groups of alewife swimming inside huge schools of millions of unrelated atlantic herring.
    Anyway, good discussion, keep it up.

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