Selecting a Beach to Survey
Choosing the correct beach at the start will make a big difference
in the ease of doing a shellfish survey and the value of your
scientific results.
The shellfish survey
is done on sandy beaches, not on rocky or pebble beaches. There
are several reasons for this. Rocky coasts often have such a wide
range of species that simply trying to identify the creatures
becomes a major task. They also tend to be more dangerous locations.
The ideal sandy beach
to sample will have clear boundaries and markers to orient to
(such as headlands or rocky reefs). You should aim to survey a
whole beach, if possible, so select one that is not too large
in terms of the length of the beach or the width of the tidal
zone. Be sure to look at the beach at extreme low tide to get
a good idea of its size.
The beach should
have a known shellfish resource, especially if people think it
is under pressure from harvesting.
The beach should
not have large banks of dead shell material or other material
that won't pass through the sieve. Otherwise the sieve gets clogged
with large amounts of extra material and it takes a long time
to sort out the live shellfish.
Be safe. Select a
sheltered beach which rarely has breaking surf. It should be easy
to get to and not involve climbing down dangerous slopes. There
will be very few west coast beaches, other than in protected harbours
that will be safe enough to survey.
Safety is
paramount and . If there is any question, don't survey.
The
sand or mud flats must be safe to walk on.
Keep records. All
your information will be useful to your group in future.
Start a Beach Log
Book to record information related to the study. The first section
will include your preliminary search for a permanent research
site. This information will be useful to help establish information
on the distribution of shellfish in your area as well as throughout
New Zealand.
Include any articles
you can find that have been written about the beaches in your
area. Some beaches have more than one name. What are the all the
names given to the beaches? Are there stories that explain why
these names were given to the beaches or the areas?
Conduct a survey
of people who have lived by the beaches for many years. What changes
have they seen in the shellfish? What do they like about the beaches?
What are their concerns? Do they think the shellfish are safe
to eat? What does the Regional Council say about tests of water
quality and shellfish quality in the area?
What is the local
Iwi? Do they have stories or memories of the condition of the
shellfish beds in the past? Were there Rahui in days gone by?
Is there a shellfish midden near the beach? Discuss the relationship
between the presence of shellfish and the location of Maori settlements
and their way of life.
Do people think there
should be protection for the shellfish now? How many people know
what the legal catch limit is?
Make a brief preliminary
survey of proposed beach sites. Are there any cockle or pipi shells
there or any other shellfish? Check along the high tide level
for shell banks and dead shells.
If there are no shells
and no evidence there were shells there, record this on your preliminary
survey information and select another beach to survey. Again,
this information will be valuable in assessing the distribution
of shellfish in New Zealand, so take care with your preliminary
surveys and keep the data in your field book.
If you find dead
shells higher on the beach (see image above) or when you dig on
a beach, but can't find living shells even after looking very
carefully with people who know the area, try to determine what
happened to the live ones. Once you are positive there
are no living shellfish present, record your efforts to find live
shells on that particular beach and select another one for your
long-term survey -one where you can find some live shells to study.
If you would like
to find out why the shellfish have vanished from a once prolific
shellfish resource, begin with a local survey of residents - does
anyone know when did the shellfish disappeared and why? Record
their stories and then try to verify the most reasonable ones.
You might want to recheck the beach the following year to see
if there is a settlement of young shellfish. If so, this offers
an opportunity to investigate what happens to them.
