Oyster restoration requires reproduction. This presentation discusses a technique for producing large amounts of fertile gametes (spat) in an intertidal zone. It produces enormous amounts of spat at low cost, from few oysters with little human intervention.

1. Highly Effective Oyster Spat
Production Technique
The Fran-Spat-Pool
June 2015
Compiled by the
Massachusetts Oyster Project
www.massoyster.org

2. The Ideal Spat Production Method for
Oyster Restoration
• Would produce millions of fertile spat
• Would be low cost
• Would require minimum infrastructure
• Would provide multiple sets per season
• Would be easy to manage

3. It only takes 16 oysters
• A female will produce 2-115 million eggs in a
spawn.
• A male will produce a billion sperm.
• With 16 oysters at least 5 are likely to be
female producing a total of 150 million eggs.
• The key is keeping them in a small area so that
the eggs are exposed to sperm and not lost in
the current.
• The heavy eggs tend to sink to the bottom.

4. Here is what you need
• A kiddie pool 4 feet in
diameter- available in
drug stores in the spring
for $8
• 16-20 oysters
• Rocks to hold kiddie pool
in place (sand may be
preferable as it is easier
to clean.)
• A location to place the
kiddie pool towards the
high end of the intertidal
zone.

5. Why it works
• The pool is flushed every 11
hours with the tides
• If the tide recedes on a sunny
day, the pool water
temperature rises.
• The oysters respond by
releasing their gametes.
• Those eggs and sperm are
concentrated in a small
volume so the fertilization rate
is very high.
• The next tidal cycle allows the
fertile spat to move out of the
pool and into the local
environs.
I am a Spat.
I will grow into an oyster.

6. Think about the location to maximize
the spat settlement.
• Do place your Fran-
Spat-Pool
– Deep in the estuary so
that released spat have a
longer area to settle
before getting washed to
sea.
– Near natural sinks or
pools that will hold the
oysters at low-tide.
– Near substrate that
oysters can attach to.
• Avoid placing your Fran
Spat Pool
– On the open ocean
where spat will be swept
away
– Areas with high flow or
flushing rates as the spat
can be carried away
– Areas with high wave
action that can disturb
your Fran-Spat-Pool

7. Cost per oyster cannot be beat.
• Pool $8
• Oyster stock $25
• Total cost $33
• Spat Produced 200 million
– 2 turns of 100 million each. We
assume
• only 5 oysters are females
producing eggs (it could be 10!)
• and that each produces 30
million or 150 million eggs each
turn. (they can put out up to 115
million eggs)
• There is a 66% fertilization rate
for 100 million vital spat each
turn or 200 million oysters.
• If 5% of the spat survive that is
10 million oysters
The cost per oyster is
3/10,000ths of a cent!
Or 0.00003 cents per oyster!

8. Ongoing results
• You will not see oysters setting in the pool.
• Assuming you place the Fran-Spat-Pool in
May, you should see settled oysters in the
area within 6 months.
• You should think about rinsing the oyster
pools periodically.

9. Disclaimer
• Mass Oyster has produced this presentation as a
service to oyster restoration programs around the
country.
• Our intention is to add to the programs a new tool- the
Fran-Spat-Pool so that they can overcome some of the
cost hurdles of oyster restoration.
• We encourage all parties interested in using the Fran-
Spat-Pool technique to first speak with their local
Department of Marine Fisheries to ensure that they are
in compliance with local regulations.
• We also ask that you use the name Fran-Spat-Pool to
honor its originator.

10. Give us your feedback
After trying the Fran-Spat-Pool let us know what
results you get…
Email us at massoyster@gmail.com