Snorkeling Season is Go - Marine Care Ricketts Point

Transcription

Snorkeling Season is Go - Marine Care Ricketts Point
Visit http://www.marinecare.org.au
Issue 35 December 2014
Decemebr013
Snorkeling Season is Go
It was a great start to the snorkeling season, with 20 of us in the water. (Three couldn't
wait for the photo). We look forward to a very big season. The new PV briefing and signing
in (and out) regime, was introduced. This will become more important as our numbers
probably double again at times, this season. Also as so many of our members now are very
experienced we also need to be aware if the skills gaps from many newbies, and buddy up
appropriately
Snorkeling Under the Mentone Cliffs
Below a Velvet
Star. You will
always see one
at least during
a dive here.
Eight of us had a mid week dive under
the Mentone Cliffs on November the 13th.
The entry is at the southern end of the
sanctuary, beside the sea scouts buildings. It is worth a look-see here once a
year. It seems to carry a lot less in terms
of fish biomass than the sanctuary, but
swimming along under imposing cliffs is a
nice change, and the algae were magnificent. Large rays were there in abundance
if you get to look under the ledges.
Image Michael Marris
On the right we have a nice shot of the
exotic weed Undaria. We have observed
that :
1.
The Undaria seems to be back in less
profusion than the forests of it during
2013, and
2.
Much of that remaining seems to be
persisting well into the summer.
Page 2
We have to be careful drawing conclusions re
such on a single season. However we can say
with certainty, that the other recent exotic,
the Northern Pacific Sea Star, is now a rarity
in the Sanctuary.
Nairm Notes
What do Pagras auratus (Snapper) and
Leptospurmam laevigatum (Coast Tea
Tree) have in common? Is it an old wives
tale? See answer on the last page.
Mytilus edulis planatus is the latin name for
the Blue mussel. They have been reappearing locally since about 2012.
They can form large beds on hard
substrates
They have no known diseases in Port
Phillip
They feed by filtering phytoplankton
Their predators are myriad, and include fish, sea stars, crabs, octopi,
rays and man.
European
shore
crab
Carcinus
maenas
They can grow up to 10 cm long and
live for 20+ years
They reach sexual maturity by 1-2
years of age and at 4-5 cms length
The sexes mostly separate.
They broadcast both sperm and eggs
which are fertilised in open water
Larvae are free swimming, and stay
in plankton for two weeks to months
They prefer to live on filamentous
materials such as finer alga or rough
textured surfaces (rocks, piles).
Recent research by Flinders University has shown a
marked increase in European shore crabs in
the last two years, particularly in the mangroves near Port Adelaide. They have 5 very
distinctive spines on both sides of the shell,
near the eyes. Also note, they have pointed
back legs, NOT back legs that look like
'paddles' . Crabs that have 'paddles' for back
legs are native species. They are common
in the Sanctuary, and perhaps we too
should begin to note their abundance via
a Citizen Science Project.
Page 3
Eclectic
The beach clean up group had a seasonal wind up BBQ on Saturday the 6th December.
Variegated limpits at Half Moon Bay
Flossie Sperring, a new MCRP member
and a first year marine science student
at Monash, has taken on a project to
assess the intertidal movements of
our local variegated limpit. This has
proven to be a far more demanding project than it first seemed. We look forward to circulating her paper in due course.
Tim Righetti, another student, has also finalized a most valuable benchmarkng exercise at
McGregors Rock, where has taken some 2000 images in located large numbers of Undaria
plants, so that we might assess density and spread of such exotic alga, in the future.
Issue 35 December 2014 Decemebr013
Page 4
The Sanctuary
Image Phil Watson
Above a beautiful image of Zebra’s in the Sanctuary. They, like the alga, seem to be
especially prolific and healthy this year.
If you are at all interested in Nudibranchs, then have a look at
this link as found by Kath Walker. http://on.fb.me/1yL9qTc
Our most common, or at least visible local nudibranch, is
Ceratsoma brevicaudatum pictured here.
Below, an increasingly common scene at the sanctuary, this
time on Wednesday 10th December. The future holds many
challenges for us in our role as sanctuary protectors.
http://bit.ly/1rVqzrn is the URL of the new BYC webcam. Click to see how useful it is.
More Recent Activities
The Great Fish Count was a success for the 25 + divers who turned up on Saturday the 13th
December, but not a great day for fish sightings. We feel that Feb/March will be a much
better time, species-wise. So, we plan to augment the GFC of December, now in its 10th
year or so, with an annual auxiliary count in late February.
Dr Kate Charlton Robb
was our most valued
guest speaker at the
December members
meeting. She spoke
with passion on the
Bay Dolphins
Click here to find out all about our very own Burrunan Dolphin,
Tursiops australis. Kate was peppered with questions for the 30 of us who attended on what
was a very stormy night.
EDITORS NOTE.
Marine Care
Have a happy and safe time over the holidays. We
hope to see you beachside.
MCRP Business Address
PO Box 7356 Beaumaris 3193
Editor: Ray Lewis
[email protected]
Find out more about MCRP.
You r b u sin ess t ag lin h ere .
Go to our website .
www.marinecare.org.au
One of the key recommendations of the Victorian Environmental Assessment Council’s
investigation into marine protected areas
was the improved demarcation of marine
sanctuary boundaries. Here is one of the
new markers,
which is mounted
on a pile that extends all the way
into the seabed,
and replaces the
traditional floating marker
buoys. This one
is at the Point
Cooke Marine
Sanctuary.
The new Minister for the Environment, Lisa
Neville, was the opposition spokesperson on
such, so she comes to the ministry with
great deal of awareness of the issues.
Lisa has kindly accepted an offer to open
the Fossils Event which will be held at the
BLSC on Saturday the 22nd February 2015.
…. Next issue likely February 2015
Speakers here will include Professors Tim
Flannery and John Buckeridge and also Dr
Erich Fitzgerald who packed out the BLSC
with is hugely popular presentation early
2014.
This event is being organised by Dr Vicki
Karalis of the Sandringham Foreshore
Assn., and it is expected that many people
will bring their fossils along for identification
by the experts present.
This will be a
gold coin donation event,
with the
proceeds
going toward
a book on our
local fossils.
ANSWER to Question on page 3: Fishermen believe that the snapper first run
when the coastal Tea Tree flowers.