NATURE

Sea, land, river

PEOPLES

Community

For earlier materials see Table of Contents

Close up -- experiment	Lower South Side
	Juveniles hanging out – at ‘Red Arrow’

This is attempt to ‘see’ what is happening among these recently settled plankton (‘immigrants’) --- to compare with previously done yellow and blue arrows

See below for image of the squares 1-4 (note the Semibalanus barnacle in lower left and it is marked with a B in image above right

Note too that 1&2 appear ‘dry’ while 3&4 seem ‘wet’ thus getting some seepage

Close up like this required to follow over time – to test hypothesis that ‘too hot’ on South Side – causing ‘depauperate’ community

Square 1

I have marked the Periwinkles (p1) and Limpets (m1) – At this size will assume all same species – though the line upper left appear to be 2 different species – with one on left being a finger limpet – all the perwinkles appear to be Littorina scutulata (l>w)

All kinds of barnacles are present – though too small to ID – note the different sizes and colors in the red circled area – perhaps the f marks a juvenile Fucus

Square 2

This one has an alga Mazaella on right side --- while not showing up well there are numerous small limpets and perwinkles in its ‘shade’

While I did not mark them there are numerous ‘dead barnacles especially just below the Mazaella – and see below

Square 3

Note that the small Fucus plants (f) plus the large Semibalanus barnacle (lower right) seem to have more diversity than the rest of the area

I have marked some of the ‘dead’ barnacles with a D – the red D is probably B. glandula (diamond shape) while the white D may be another species

The Red enclosed area is thick with barnacles – the bg is probably B.glandula (based upon color & diamond) – others could be different species or merely less mature

	Square 4
	Again there is a lot of small life here – perhaps more small limpets and perwinkles than any other square – here I have noted the areas of Dead barnacles (B glandula mostly) – again there is more diversity around the Fucus and Semibalanus --- but still I would estimate almost 40% juvenile barnacle coverage remaining areas

Will have to come back in a month to see what has changed

Previous Sewer Outfall:

1--May overview of Outfall project

2—May attempt to monitor South side but new critters too small to ID

3—look at lower end w ‘seepage’ N vs S

4—earlier where 1^st see North has different spp than South

‘Lower South Side: ’yellow arrow and blue arrows

Conclusions??

Well comments any ways --- at this stage there is maybe 75% coverage in these squares – as few adults present (neither limpets, periwinkles nor few algae and barnacles) – something must be happening to juveniles to prevent ‘growing up’ – we do see numerous small barnacles that are already ‘dead’ – But I did not see barnacle predator (Nucella) present ---

There are sufficient herbivores (limpets and periwinkles) that one could suggest they will soon run out of food – as few algae and no ‘scum’ (diatoms etc)

Created by LG on 20/7/2007

Last updated on Sunday, July 19, 2009