UWCRCN Ecology field trip
Svanøy 25-26 May 2012
Group 4 project:
Study of the Sea shore ecosystem on the island of Svanøy
Why are the organisms found where they are found?
INTRODUCTION
There are several definitions of Ecology. The most common one: Ecology is study of interaction between
organisms and their living and non-living environment. The most practical definition: Ecology is the study of
abundance and distribution of organisms. These two definitions are not contradictory because the gross
interaction between organisms (populations) can be deduced by relating where they can be found (distribution),
and how many of them are there (abundance and diversity) - to physical and chemical properties of their habitat.
The seashores (those with a significant tidal difference) are ecological “school examples” because the physical
and chemical factors are present in a sharp, obvious and accessible environmental gradients, within a short
distance (several meters): from the water line at the lowest tide to the top line of spraying by waves. The
populations of characteristic organisms are, typically, clearly stratified along that gradient.
Another common example of such stratification of populations due to an environmental gradient is a mountain
slope; deciduous forest at the bottom, evergreen forest, low forest, grassland, mosses & lichens. Similar gradient
exists in terrestrial ecosystems between equator and polar regions. But the relevant physical and chemical
gradients for those are spread along thousands of meters or thousands of kilometers.
Along Norwegian coast marine ecologists distinguish two zones of the rocky seashore ecosystem:
1. The Splash Zone – washed and sprayed by waves, but not immersed.
Visible as darkened rock with yellow lichen patches
2. The Intertidal Zone – periodically immersed in seawater.
Its top line is clearly defined by the uppermost macroscopic algae
AIMS
On the island of Svanøy:

Establish the distribution (stratification) of common and/or dominant and/or characteristic species
(populations) between the lowest tide-line and the highest line of sprayed rock on the sea shore

How does the diversity of species and quantitative proportion of primary producers and
consumers change between the lowest tide line to the highest line of sprayed rock on the sea shore.

Relate that (distribution and diversity) to physical and chemical factors (environmental gradients)
which depict the micro-habitats of those populations
HYPOTHESES: 1., 2., 3.
TEAM WORK
The teams will consist of 8-9 students from all 4 sciences. The students will decide among themselves what
exactly needs to be done and how – and who will do which job. Ecology and most of the modern science is
performed in teams – this is an exposure to teamwork (it will be assessed :-).
This investigation and report will be assessed (only ESS and BIO) for DCP, CE, MS, PS and for Physics and
Chemistry students PS, (possibly more).
Make sure that it is indicated in your raw data & written report which particular data you collected yourself.
If you are presenting in your report a contribution worked out and obtained by someone else (eg. a physics
of chemistry student) – you must clearly indicate that.
AVAILABLE EQUIPMENT:
Meter tape, clinometer (measures inclination), iron quadrates (50cm x 50cm), meter measure,
magnetic compass, square grids 10x10cm2, transparent plastic tubing, infrared thermometers,
lux-meters, containers, chemical probes (?), magnifiers, millimeter paper & note pad,
waterproof notebook and pen, pencil, booklet of marine species
……………………………………………………………………………………………………………………………………………………………………
To understand and/or be able to use and/or do before the trip :
Characteristic species (identified by name and memorized) – Bio & ESS
General marine ecology (benthos, pelagial) – Bio & ESS
The marine tides – why and how ?
Ecological methods: cover percentage, belt transect, use of quadrats (cover percentage),
Use of clinometer, infrared thermometer, lux-meter, chemical probes (??)
Measuring the height of a slope using the water tubing – or other method (PHY)?
Standard ways of representing abundance and distribution of organisms
(kite diagrams, pictographs, ecological pyramids, index of diversity)
How to draw a precise profile of a transect (with physical and chemical measurements ) – Phy &
Chem .
Hints on crucial ABIOTIC factors on Sea shores
(on microhabitat of individual organisms)
1. Time of immersion in sea water per 24h
2. inclination of substrate
3. orientation to sides of the world
4. exposure to light
5. temperature of the substrate (related to 1,2,3,4)
6. salinity
7. consequential degree of exposure to desiccation
most important: degree of daily variation of those factors at different distances / elevations
from the water line
NOTE: For partly or completely sessile organisms (attached to rock) very important is the degree of
exposure to the physical force of waves. That is difficult to measure on spot (we hope for nice and
calm weather) but it is directly related to inclination of the substrate they are attached to.
An interesting approach: Perhaps one can find out about those physical forces by measuring a force
needed to dis-attach a limpet, barnacle or kelp from their substrate. On the steepest and most exposed
stretches of intertidal shore some organisms are not present obviously because the power of waves is
bigger then their ability to hold to substrate. Another “cute” problem: does the power of attachment
(ability to resist wave action) depend (or not) on the size of the organism?