The
Shellfish Farm News
September 2003
As summer
winds down and we head into fall, shellfish farmers in Baynes
Sound are completing the years’ seeding in anticipation
of the fall plankton blooms. The blooms boost the size of
the seed heading into winter and thereby improve its’
survival. Even with their best efforts, up to one-half of
the seed planted by shellfish farmers is consumed by wildlife
such as crabs, seastars and birds. Through years of experience
shellfish farmers learn where and when the best times for
seeding occur. For example, seeding oysters on some deepwater
sites is not possible in the early spring as the seastars
will overwhelm the crop at that time of year and inflict
heavy losses. By seeding later in the year the oysters will
grow large enough by the following spring to outpace the
next generation of seastars in size (Seastars can generally
only eat an oyster that is no larger than they are). On
some sites, it’s a race to see who will harvest more
oysters – the farmers or the seastars! Small seastars
and organisms like sea urchins can actually help the oyster
crop by cleaning off hitchhikers like mussels and seaweed
that also naturally settle on the oysters. With over 70
years of experience in farming the waters of Baynes Sound,
shellfish growers have learned that working with Mother
Nature is the only way to succeed!
September
also marks the end of “daylight tides” –
that is, low tides at this time of year switch from occurring
in the daylight to the night. Night tides will last from
October to March and require headlamps for working on the
beach leases. Tides are caused by the gravitational pull
of the sun and the moon. When the sun and moon line up with
each other they produce a stronger combined gravitational
force that results in larger than normal tides. These large
tides are associated with the full moon and new moon and
are called spring tides (not named after the season) . Neap
tides are the other kind of tide and occur when the sun
and moon do not line up with the earth. These are weaker
tides that are associated with the first and last quarter
of the moon each month. Shellfish farmers schedule their
work with the tide tables and can work on their beach crops
of clams and oysters during the two spring tide periods
each month, when the crops are accessible for 4 to 6 hours
per day.
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