Alternative Materials - Making Oyster Shell Go Further

[Scott McGuire]

Here's a pretty neat article from the Charelston Area. It seems they're struggling with many of the same issues we are - but I really like this "Castle" idea. It's combined the use of concrete structure, and shell.

Turning the tide The Post and Courier - Charleston SC newspaper (http://www.postandcourier.com/news/2009/aug/26/turning-the-tide/)

[paxfish]

Yeah - that's cool - they can do that in seemingly shallow water because their tides are like 7 feet, and the winter is mild enough that the oysters can stay out of the water at low tide.

[Scott McGuire]

Yep, you're exactly right. I like this article because they acknowledge that shell is a limited resource, and they're using alternatives to accomplish the same goal.

[heimdall]

Is it true that, excepting used concrete (if it is available), all other alternatives cost twice as much as natural shell????

[Scott McGuire]

I think it depends how you calculate the cost of shell, Mr. Heimdall. Shell from shucking houses cost about 1.00/bushel, but there aren't too many shucking houses - and not a lot of shell. Then there's transportation, and other incidental costs. The same goes for dredged shell. According to the MOW dredge permit application, shell dredged from Man O War would cost about $1 per bushel as well ($16/cubic yard in 2008, page 10). On the same page there is a table that shows estimated costs of alternative materials. They are more expensive. Sometimes double, triple, or even more than triple that of shucking house shell, or dredged shell.

While on the face it may seem like dredged shell from the upper bay is a good deal, but many believe that the cost of dredging to the upper bay has not been properly accounted. As a result of previous dredging efforts fishing has suffered, live bottom has not returned, water quality was degraded during dredging, etc. The point is, upper bay fishermen are being asked to sacrifice again, and with dubious results from the last 40 years they are unwilling to export their shells when the cost to them has not been fully accounted. Recreational fishermen, charterboat operators, and commercial fishermen that use MOWS would argue that the area is too valuable to send down the bay.

That being said, the task of restoring oysters is so large and daunting, we could dredge 100% of MOWS (est 100 Million bushels) and still not have enough shell. Without enough shell to be used as the raw material to restore oysters, no matter what, we are going to have to explore alternative materials. We need a new approach, and a real plan to restore oysters that includes alternative material - at least at the start. Shell is going to be required, but the limited resource has to be properly accounted for and valued..

The part of this equation that I understand the least, is why we are (collectively) so frivolous with our limited shell resources. While I realize oysters were once much more plentiful, so there was no shortage of shell. It baffles me, that we could have ever gotten so dependent on shell from other sources (like dredged shell) to begin with. It baffles me because these animals create shell for free – at twice the amount that was used initially! In fact, depending on they type of oyster, it could even be more than twice the amount of shell created.

In the case of spat on shell, for every shell used in the setting process we could assume that 1 oyster lives to maturity (given good conditions). If we start with 2 oyster shells, and each one produces 1 oyster, in 1-3 years, we now have 6 shells. (2 we started with, and 4 new ones)

In the case of cultchless oysters – oyster larvae is set on tiny fragments of shell, no bigger than a chip of paint. Each oyster that lives to maturity produces 2 new shells.

It seems to me that, with a concerted effort in aquaculture, we could create a shell budget based on using initial stockpiles of shell by requiring a certain return. It might take a while to build up shell reserves, but it would at least be a plan – and over time it could create enough shell to grow the aquaculture industry and perform restoration.

(FYI-shell budget idea stolen from a friend)

[Matt]

why not orchestrate an amnesty day for 3 gallon flush toilets and use the porcelain as substrate. Oysters grow well on toilets! And the bay hates 3 gallons per flush.

[Patapsco Mike]

The Army Corps recently put out bids for alternate materials (concrete and stone) to create a few small oyster reefs in the Severn River. The one bid received was almost exactly 4 times as expensive as shell would have been. The bid is so high it's putting the whole project in jeopardy.

Shell from shucking houses costs 50 cents a bushel, but that is too valuable to put on the bottom. 100% of that goes to the two state hatcheries and they used every bit of it to generate the 600 million plus oysters produced by Horn Point and Piney Point this year.

Jon Farrington's "shell engine" idea Scott refers to looks good on paper, but it just doesn't work out in the water (not to mention that step one in the shell engine is "get shell").

Shell is the best and least expensive material for oyster restoration. If you want to see cost-effective, large scale oyster restoration in Chesapeake Bay, you need shell. It's that simple. While I do get the NIMBY arguments against dredging, I completely disagree with the assertion that oyster restoration is a frivolous use of shell. I don't think there could be any better use.

[Matt]

NIMBY? Hasty generalization. Proposed nonsense not in my backyard.

An adequate case for this activity - without a moratorium - has not been made.

Stop wasting tax dollars.

[Barefoot]

NIMBY? Proposed nonsense not in my backyard.


Not in mine either.

[Scott McGuire]

Just to clear things up, I was thinking about repletion when I mentioned the frivolous use of shell. Over the last 40 years, the repletion program caused us all to be addicted to shell, and now the shell resource is in short supply. The addiction is so bad, that we have to argue about who gets available shell. We're forced to rank industry, aquaculture, and restoration against eachother, and we're again forced to consider stripping shell from the last available deposit when this idea has already been shouted down several times in the few decades.

It's easy to say we "shoulda, coulda", but we can't turn back time on the way shell was used in the past. What we can do is ask ourselves: "what is the true cost of dredging shell?", "what would it cost to take a different approach?", and "what would it take to put the resource first?"

[Patapsco Mike]

Scott is correct that restoration, aquaculture, and repletion all need shell. Efforts undertaken to prevent the recovering of shell will slow all three.

[Matt]

Shell for restoration. Great. An adequate business case still has not been made to spend more tax dollars on restoration. The record clearly shows that millions of dollars have already been wasted. Virtually no improvement in wild oysters, the health of our marine ecosystem, or the industry, as a result of oyster restoration.

Putting the resource first involves hard decisions. At 1% of natural abundance, the first hard decision is further exploitation. Choosing to ignore this issue, in my opinion, gets to an issue whether DNR can do the right thing.

[heimdall]

Just to clear things up, I was thinking about repletion when I mentioned the frivolous use of shell. Over the last 40 years, the repletion program caused us all to be addicted to shell, and now the shell resource is in short supply. The addiction is so bad, that we have to argue about who gets available shell. We're forced to rank industry, aquaculture, and restoration against eachother, and we're again forced to consider stripping shell from the last available deposit when this idea has already been shouted down several times in the few decades.

It's easy to say we "shoulda, coulda", but we can't turn back time on the way shell was used in the past. What we can do is ask ourselves: "what is the true cost of dredging shell?", "what would it cost to take a different approach?", and "what would it take to put the resource first?"

Isn't it CCA's position to use non shell to try and curtail commercial harvest?

Also I can't believe that MOW has the only fossil shell deposits in the bay.

When was the last survey done on total fossil deposits for the whole bay?

[Scott McGuire]

Heimdall,
The two links below should clarify CCA's position for you.
CCA Maryland Position Papers (http://www.ccamd.org/advocacy/position_statements/oyster_restoration_shell_dredging.htm)
CCA Maryland Position Papers (http://www.ccamd.org/advocacy/position_statements/PEIS_oyster_restoration.htm)

Regarding other shell deposits - the Dredging Permit Application discusses what's available where. I don't know about survey's but I'm sure Mike could shed some light on that question.
http://www.dnr.state.md.us/fisheries/oysters/ManOWarApplication709web.pdf

Also, there is another permit application that does not have the same opposition as the MOWS permit application. It is a permit app for the recovery of 25M bushels of previously deployed shell. It is shell that's been dredged out of the upperbay and used over the last 40 years. Much of it has been spread out and fallen off of bars, but some of it is still good shell and can be recovered for reuse.

It seems to me, that we could get a good start on restoration if we used previously deployed shell, and alternative materials. (just my opinion)

[Patapsco Mike]

Some say Man O War is the last shell deposit to dramatize the issue. Man O War is by no means the last deposit, there are a lot of areas remaining. Anyone who has read the recent dredging proposal (which is on the DNR website still) would see the table documenting known shell resources, and these are only a fraction of what's out there. Man O War is the largest reserve that we know of, and it's not in a striped bass spawning reach. This is why it's being proposed as an area to dredge.

[Matt]

Seems like hope against hope that we can recover shell that was dumped before, with unsuccessful results, and use it again for success. FWIW moving oyster shell is thought to be one of the ways disease was spread around the bay. Isn't this why the fossil shells are desired? Oyster shells are a vector for disease. Don't take my word for it, plenty of info out there.

[Scott McGuire]

I'd like to see a restoration plan and a spend plan that explains where the Money will materialize from to remove 30 million bushels of shell, do all of the baseline studies, "repair" the damage dredging did, and fund a major restoration activity. Even if it's spread over 10 years, it seems unlikely, and it doesn't even begin to factor the cascade of costs that will be encountered.

[Matt]

yes, now thats message that makes sense. "Restoration" costs money. These activities have not produced much in Md's part of the bay.

I think its prudent if not wise to make advocates prove out the value of these activities.