Summer Berm

Despite the near tropical storms and downpours over the past fortnight, the summer berm is developing all along the beach at Venus Bay and only a few fresh erosion scarps can be seen. This upper beach is already flattening under mainly strong northerly winds and this brings promise of a wider summer berm this year. The full moon is tonight and it will be interesting just how high the overnight tide might reach.

Have a look at the night sky

Just got an alert of extreme activity from aurora australia right now, and hopefully through tonight. So It may actually be visible from Venus Bay, low in the southern sky.
For more up to date forecast see the University of Alaska Geophysical Institute and then Select the antartic map in the "select a map" box on the left hand column.

Photo by Samuel Blanc.

Does Marram Grass Encourage Deeper Erosion?

The more I look the more I see evidence that recent erosion is strongest (ie leaving the tallest erosion scarp) in areas where the dunes are heavily covered by marram grass. Compared with areas where only runners of coastal spinifex, appear to leave a partially covered and “less well protected” dune front. These two photos where taken from the same location and the difference is very clear.

The photo on the right is looking slightly north to an area of heavy marram grass on the dune, and two recent erosion events. Further the beach infront of this is still showing its steeper curves winter shape. Compare this with the photo on the right, just taken straight-on here only a few runners of the coastal spinifex have regrown in front of previous erosion, but the slope is already flatter and the beach infront of this point has already started to develop its summer shape. This is often termed the summer berm. The beach above the high water mark has started to dry out and the curve of the upper becah is being flattened by wind erosion, leaving the characteristic wind blown ripple marks, with extra seaweed & other heavier debris to collect sand with wind gutters around the base and often a wind shadow of dry sand. It is the development of this summer berm that provides the best home for beach nesting birds, a rest place for animals and migrating bird (like penguins, terns and seals).

For a long time I have assumed that the taller erosions scarps are associated with deeper gutters out in the sand bars, and I still see that there will be a distinct gutter or channel in the vicinity of fresh erosion but the relationship with marram grass on the foredunes does seem to be becoming more compelling.

So  the big question is -
Does marram grass encourage deeper erosion of the dunes?

Storms & More Erosion

The past few weeks has seen more erosion along the Venus Bay beach in many locations. The profile of the upper beach is also steeper (more the classic winter berm) in front of the recent erosion. The erosion scarps are up to 3m high, probably the highest this year.

These are classic features of low pressure (storm surge) corresponding with higher tides and strong on-shore swells. You’ll see the sand is still there, as a wider beach and sand bars at low tide.

Hooded Plover Workshop

You are invited to a Hooded Plover Workshop coming up on Saturday15th October at the Venus Bay Surf Life Saving Club. Join us to find out more about these quirky,  but vulnerable little birds that live on Venus Bay beach and other beaches in Cape Liptrap Coastal Park. The event is part of our Coastcare Victoria Community Grant project to protect Hooded Plovers within Cape Liptrap Coastal Park in partnership with Birds Australia and Parks Victoria
Saturday 15th October
Venus Bay Surf Life Saving Club
Start from 9.30am with opportunity to participate in half or whole day program finishing around 3pm
Morning session presenters:  Tanya Pyk from Birds Australia and Jonathon Stevenson from Parks Victoria 

Morning Tea and Lunch provided but BYO special dietary requirements.
Please RSVP to Tanya Pyk t.pyk@birdsaustralia.com.au or ph:03 9347 0757